METHODS OF TOUGHENING A GLASS SHEET

The present invention relates to the hardening of glass sheets. More particularly, it is the bending of glass sheets that are to be then cured and used for the production of glazing for vehicles, for example automotive windshields and aircraft. Such single glass sheet may be a vehicle windshield, or form one of the thicknesses of a windshield glass composite laminated.

It is conventional joining two thin glass sheets to form a windshield overlapping with interposition of a layer of transparent plastic material, for example polyvinyl butyral. In a windscreen, the two glass sheets may have been subjected to one and the other is annealing, curing and is, according to a common technique, is produced a laminated windshield double fragmentation pattern using.

a sheet of annealed glass on the outer side and a hardened or tempered glass sheet inner side.

With a windscreen, the visibility remains even if the outer sheet annealed is broken by a sharp edges, while the inner sheet is rapidly quenched fragmented if it is hit by the head of an occupant of the vehicle.

In general, for making a sheet of tempered glass for windshield, is given by first chopping to the glass sheet a desired contour. The then carries the sheet to the bending temperature while passing through a heating furnace, suspended to grippers carried by an overhead conveyor which the then interposed between dies Glass vertical; these matrices meet at the print sheet and by bending the desired curvature.

The shaped sheet is conveyed between frames blowing when it is to be hardened by quenching or through a lehr when it is to be annealed is suspended to grippers which grip its upper edge.

-For Glass two glass sheets must have curvatures matching precisely for subsequent combined to form a laminated glazing, it is customary to perform by droop technique by horizontally setting the two sheets superimposed on a mold ~ bending by collapsing, and by conveying them through a furnace where they are heated and collapse together, to take the desired curvatures matching In one disclosed technique most recently, is suspended by means of clips a flat glass sheet cut to the desired contour in a heating furnace whose base has an opening and is down, when it reaches the bending temperature, between dies Glass which meet at the sheet held and print the desired curvature, and then goes on to pass through, by re-downward movement, a pre-cooling stage, where it is subjected to blowing ' cooling air, immediately followed by immersion in a quench liquid, e.g. mineral oil with or without a minor amount of additive low boiling point. The toluene and carbon tetrachloride are suitable additives. This technique is particularly effective for obtaining high strength glass for arrangement and of curved glass and quenched, of 1.5 to 5 mm thickness, for the manufacture of automotive laminated windshield.

It is desirable, during the bending of a glass sheet, not to wear the sheet, prior to bending, at a temperature above that required for a satisfactory bending, in order to avoid the risk of unallowable deformation of the sheet.

The invention concerns mainly allow 1' obtaining a bent glass sheet high mechanical strength with Heating printed to the sheet after shaping to a temperature pre-quench high.

The invention provides a method of hardening of.

glass sheet comprising contacting by. Heating the glass sheet in a thermal state preset for its shaping, joining on the sheet molding surfaces, maintained in the same thermal condition that the glass sheet, 'to separate said surfaces of the sheet, followed by heating the sheet of' glass in a thermal state pre-quench and tempering the sheet by bringing its faces in contact with a cooling medium.

The invention further relates to a method for bending and. glass sheet quenching, comprising contacting by heating a glass sheet in the thermal state preset desired for bending, to be joined on the sheet matrices Glass, maintained in the same predetermined thermal condition that the sheet, to move the dies Glass of the bent glass sheet, to be applied to the glass sheet a domed Heating raising its temperature throughout its mass and quenching the sheet by contact with a cooling medium.

According. one embodiment of the invention, is heated the glass sheet to a bending temperature preset, the matrices is maintained to " Glass at this temperature and bending the bent glass sheet to a temperature of the pre-quench is greater than temperature, bending before bringing it into contact with the cooling medium.

When the sheet is. glass sodocalcosilicique, the bending temperature may be 550 to 650 °C and said temperature pre-quench is 620 to 720 °C.

b1invention further includes positioning the glass sheet in a thermal state pre-tempered by heating raising its temperature throughout its thickness and to further heat the leading edge that the rear edge of the front sheet contact with the medium quench. ~ _*

In one embodiment of the invention, is lowered the bent glass sheet, at a first speed, in a die area Heating whose height is greater than that of the sheet and, a prefixed time after penetration the upper edge of the sheet in the heating zone and while the foil is still fully in this area, accelerating the sheet to its penetration in an area where it makes. r have act with the medium quench, to further heat the lower edge than the upper edge of the sheet before entering the quench medium.

The sheet can be accelerated when its lower edge reaches the base of the heating zone.

Preferably, the temperature of the leading end of the glass sheet has a deviation in addition to 5 to 40 °C by ' respect to the back edge of the sheet and there is a temperature gradient of substantially liné area between the leading edge and the trailing edge of the sheet. The temperature of the leading edge may be 20° G greater than that of the rear edge of the sheet. Can be imparted to the sheet a substantially linear gradient between the temperature of the leading edge, of 700 °C, and that of its rear edge, of 680 °C.

In another embodiment, by heating is given to the sheet, before shaping, thermal distribution such that the edge entering the first in contact with the liquid quench either warmer that its opposite edge and 1' is established substantially the same temperature distribution in the shaping surfaces.

Invention can be displayed the glass sheet has currents cooling gas prior to its contact with the cool-medium to establish in its thickness gradients, in temperature between the middle and its faces.

1' invention.vise also any tempered glass sheet obtained by the process of the invention.

For understanding the invention, is is describe

example one embodiment by referring to the des-In the drawings:

-figure 1 represents in elevation, with cutting, an apparatus according to the invention comprises a loading station of flat sheets of a glass, a heating furnace, a station and a tempering station bomhage the liquid;

-figure 2 is a side view of the loading station

and the input end of the kiln that shown on Figure 1, with peel for viewing support rollers almost vertical and lower rollers associated, located at the loading station and in the furnace;

-figure 3 is a cross-sectional view along the line V-V of

figure 2 shows the layout provided with heating elements mounted in, the furnace;

-the ' figure 4 is a side view of a carriage on which rests a glass sheet as it is transported in the furnace;

there-Figure 5 is a cross-sectional view along the line X-X of

figure 4 indicating the disposition of the carriage and the glass sheet relative to the rollers almost vertical and short lower rollers of the furnace;

figure 6-shows the arrangement provided with electric heating elements mounted on a side wall of the furnace;

figure 7-shows schematically a mounting-controlled thyristors adjusting the power supply of one of the groups of heating elements shown in Figure 6,5

.-figure 8 shows the arrangement provided with electric heating elements on the opposite side wall of the furnace;

figure 9-is a view of detail reproducing a portion of Figure 1 and showing 1' assembly including a body pivot includes fabrics Glass male and female and is arranged to swing a position where its inclination conforms to that of the rollers of the furnace almost vertical to a horizontal position overlying the heat treatment apparatus, in which move down the bent glass sheets;

-figures 10A and 10B show together the raft container partially sectional view along the line XVTII - XVTII of Figure 16;

figure 11-is a horizontal cross-sectional view of the dome die male;

-figures 12Α, 12B and -120 together form a view in elevation of a rod gripper holding, from which there are suspended clamps for gripping the upper edge of a glass sheet interposed between the matrices Glass male and female, and of the lifting mechanism which is suspended the gripper holding bar;

-figures 13A ., 13B and 13C together constitute a plan view of a portion of the lifting mechanism qt of the. suspension structure of the gripper holding bar;

-figure 14 is a cross-sectional view vertical panels having additional heating devices located below.

the raft container and between which a bent glass sheet descends to be heated prior to temper-,

-figure 15. is a sectional view of the lower part of the pit below the raft container, showing in detail a stage pre-cooling vessel and a quench liquid;

-figure 16 shows schematically the network control hydraulic the raft container, and matrices Glass. of the suspension structure, 1a gripper holding bar;

figure 17-represents schematically the. pneumatic network mechanism which actuates the opening of the clamps, the brakes of the lifting mechanism and determines the rotational speed of the hoisting motor, and-,

-figures 18,19 and 20 represent schematically arrangements which control the switching networks hydraulic and pneumatic shown in Figures 16 and 17.\

Figure 1 represents the set of an apparatus for carrying out of the invention for the Heating, the bending and the ^ quenching glass sheet, throughout that process, are transported through the apparatus standing, i.e. nearly vertical positions during vertical Heating and after bending and during quenching liquid.

The furnace chamber, designated by the general reference 1, has a rectangular cross section, has a floor having a particular profile 1 as' indiquerafrepose, with an inclination of about 5° from vertical, in a frame main lower crosspieces 2 the ends of which are connected by longitudinal members 3Sur the ends of the lower crossheads stand 4 on the vertical posts having an inclination, for example of 5 °, as shown clearly in Figures 4 and 4 5Les tops of the stiles are connected in pairs by upper cross beams 5, inclined at about 5° on 1 * horizontal.

The floor of the furnace rests. on sleepers 6, which connect the lower sections of the uprights 4et have the desired profile to conform to the profile of the floor of the furnace. The floor has an inclined plane from top to has to the base of a side wall in order to permit harvesting the cullet possibly falling on the floor through openings near the base of said side wall and terminated by the hinged doors.

The oven 1 is a metal furnace refractory lining, having side walls that extend to the top of the floor and are integral with a suspended roof to top crossbeams 5Des longitudinal members 7, fixed along ' from the top of the furnace, carry gearboxes in which enter the vertices of a series of spaced rolls 8, almost vertical, inclined which give support to the glass sheets 9 to be transported across the furnace to impart -1 bomhage, and a. quenching liquid or annealing. _AOE280A2AO>

The rollers 8 are covered with asbestos or are heat-resistant steel, have all on the vertical inclination of 2 to 10 °, for example of 5 °, and ' are part of a glass sheet conveyor which passes right through the furnace 1, a loading station designated by the general reference 10 to a bending station 11. The rollers have a diameter of 6.5 cm and exits oven distributed in the range of 19 cm. The nip can reach 30 cm in the region of the outlet end of the furnace, wherein the lens arrival at its final temperature. A the input end of the kiln, wherein the lens is not heated, 1' spacing can be larger for example 38 cm or more, with the proviso that the rollers are numerous enough to support glass sheet on its entire length, in a stable equilibrium.

The transport has a movable support formed by a trolley 12, on which rests the lower edge of the glass sheet 9, by short rouleauxr lower 13 projecting into the spaces between the rollers almost vertical 8, near the bases of these rollers 8, both the loading station 10 that in the furnace 1, and by drive means for advancing the carriage 12 through the furnace, the glass sheet 9 bearing against the rollers almost vertical 8.

Short lower rollers 15, also heat-resistant steel or coated with asbestos, form an acute angle, of 50° in the example selected, with the rollers 8.'

The carriage 12, represented more in. detail in Figures 4 and 5" has a V-section, having two tines together are the same acute angle as the axes of the rollers 8 with the axes of the rollers 13 * The arms of the carriage are in wiping contact with the rollers 8 and 13, driven at the same speed as the exposed, so that the carriage carrying the sheet is advanced through the kiln by this sliding contact with the rollers both lower 13 8 that almost vertical. Initially, only the upper edge of the sheet lies on the surfaces rotating the rollers 8 but, as it is heated by advancing in the furnace, the sheet tends to collapse against the support surfaces formed by these transient * The bottom edge of the sheet. rests on support members carried by the carriage 12 profiles and is slightly offset thereon with respect to the support plane defined by the rollers 8, so that the sheet can undergo a sagging, with lower deformation to a prescribed limit, while being held upright and without its lower edge escapes from the carriage.

In operation, is fixed the thermal conditions in the furnace, and the time taken by the carriage carrying the glass sheet through the heating zone, -according to the thickness and height of the sheet, the inclination of the support rolls on the vertical and the offset between the lower edge of the glass sheet and the rollers of holder so that the sheet a thermal condition preset, the thermal conditions and the set time being selected so that the glass sheet can in during heating, by collapsing against the support rollers, that a deformation less than the maximum allowable value prior to bending. The heating mode of the glass sheet through the heating zone is disclosed in French patent application date by the deposited under the № 74,24967 Requester

Typically, the offset is approximately 2 to 4 mm and the deformation allowable limit depends on the quality, in particular optical quality, required for the product. For glass sheets incorporated into windows of vehicle, for which the optical requirements are stringent, it can be brought to limit the deformation of the glass sheets at the stage of initial collapse prior to the occurrence of a bulge. Sometimes, is' can tolerate a bulge of height of up to 0.5 mm.

When the governing the quality requirements are less stringent, may be allowed a bulge of greater height and. to 0.5 mm for example up to 4.0 mm.

It has been found that the inclination on the vertical of the sheet initially supported by bearing against the rollers 8 may be 2 to 10° for heating glass sheets sodocalcosilicique of a thickness of 1.5 to 15 mm at a temperature of 580 to 680 G or even 700°^WHEREIN G, which corresponds to the usual range of temperatures at which the glass is heated sodocalcosilicique before the " bending or tempering.

The upper rollers 8, almost vertical, rest with their lower ends in bearings carried by self-centering of the parallel longitudinal members that extend underneath the floor of the furnace and rest on the shaped webs 6.

The ten first of the plurality of rollers 8 constitute the loading station 10 and five short lower rollers 13 are distributed in alternate spaces between the rolls 8.

At bending station are arranged vertically matrices Glass 15 and 16, represented in particular in Figures 9, and 10B 10A. The female die 15, slatted frame, cooperates with a male die 16, having a surface continuous Glass and is represented in detail in Figure 11. The matrices represented are rigid, but matrices can be used to hinged wings pivoting by the operation of a known kind for bending mechanism elements windscreen to complex curvature.

The matrices are accommodated in a box oscillating 17, and refractory lining, defining a heated chamber and enclosed and is traversed by a conveyor, formed of upper rollers 8 and lower 13, similar to that through the furnace, that it prolongs. The upper rollers 18 which are located, in the raft container 17, in the region of the curved dies have bearing surfaces shortened to that the frame to elaire. of the female die can be inserted between the rollers and the cross.

Beyond the outlet of the cash pumphandle 17, other rollers 8 almost vertical and lower short 13 extend the conveyor to receive each carriage 12, once the sheet that it raised supporting to be curved between the matricesb

All the rollers located at the loading station, in the furnace and in the body are driven from the same motor. The located beyond the outlet of the raft container comprise a separate transmission and all transmissions are controlled as is exposed so that a glass sheet 9 can be advanced slowly from the charging station to 1' entrance of the furnace 1, be accelerated to its penetration into the furnace, and pass through the oven at a moderate rate suitable for heating the same. At the end of the time set for the heating in the furnace, the sheet is accelerated during passage of the oven on the almost vertical courtsrouleaux 18 interposed between the dies to be bent and the carriage is stopped when the glass sheet is exactly between ' the dies.

The raft container is carried, by burners to-gas shown in Figure 9, at the temperature reached by the glass during pass through the oven, so that the dies Glass are at the same temperature that the sheets which reach their curved to be-

The raft container 17 is mounted on an oscillating frame having solid lower crosspieces 20 mounted on pivots centre 21. A hydraulic cylinder attached to the-middle of a side beam of the oscillating frame oscillates the latter between an inclined at 5^Q about to the horizontal, in which the rollers 18 have, on the vertical, the same inclination as the rollers 8 of the furnace, and a horizontal position in which the rollers 18 are vertical.

Initially, the body is in an inclined position and the dome die male advance when the carriage carrying a glass sheet pumphandle and enters the case, after a hot glass sheet interposed between the dies, the female die 15 is, between the rollers 18, pressing the sheet against the die with, and the swing frame goes off horizontaie during the bending of the sheet. During advance of the female die, the glass sheet is lifted from the carriage by fingers, carried by this matrix, which slip under the lower edge of the sheet to raise the same. When the oscillating frame is horizontal, a bar gripper holding 23, supporting clamps 22 gripping glass sheet is lowered by a lifting mechanism indicated-in 25, itself vertically movable.

It is provided, in the upper edges of the matrices 16 and 15 notches in which the clips 22 engage to be able to grasp by its upper edge the glass sheet held between the dies.

TTne times the glass sheet lifted from the carriage 12 the latter is large body speed to output conveyor 8 before the oscillating frame returns in a horizontal position, when the dies separate, and the sheet, then suspended vertically to the clamps, descends through an opening in the bottom of the case further processing..

During pass through the oven 1, each sheet is heated to a bending temperature, e.g. 610 °C, at which it can undergo bending a satisfactory and be gripped by the grippers 22, without being softened enough so that its surface state at risk of being affected by the bending.

When the bent glass sheet is to quenching, especially when it must have ' high mechanical strength, it is indicated it first be subjected to an additional heater, the bearing for instance to 680 °C etr, according to the embodiment shown in Figure 1, upon such a shaped sheet Heating of before the extra be quenched by liquid into a quench vessel 26 housed in a pit formed below the raft container 17-

Crossed Soon the outlet opening in the bottom of the raft container, the sheet is conveyed between two sets of electrical heating elements 27, arranged as shown and directed to both sides. Its climbing down between these elements, the glass sheet which is to its bending temperature of 610 °C for example, is carried on its entire thickness to a temperature of the pre-quench more close to the softening point of the glass, e.g. 680 °C. The shaped sheet can descend uniform velocity, so as to be completely at a temperature as uniform as possible. Alternatively, it can be accelerated. between the heating elements for a uniform temperature gradient appears between its lower rim, highly heated, and its upper edge, least heated.

May be printed to the sheet such a temperature gradient front of the dome by operating groups' lower heating elements mounted, on the furnace wall point higher than that of upper groups, or by placing the lower groups closer to the glass, as exposed to figures 10A and about 3. For example, the operating temperatures can be 800 °C has in the furnace, of 750 °C to mi-height and 700 °C at the top of the furnace. The male die 16 (Figure 11) is then heated by heating elements inner 511 which are incorporated to have a thermal gradient concordant with that printed to the glass sheet by such a furnace, as exposed to about Figure 11.

Below of extra heating elements 27 are mounted two blowing boxes 28, both supplied with air cooling to room temperature, for example about 30 °C, uniformly projected by nozzles 29 incorporated into the boxes, on both sides of the glass sheet. The pre-cooling printed to the sides of the sheet after heating extra immediately generates temperature gradients between the medium and the two sides of the sheet. The medium of the sheet substantially retains the temperature acquired by extra Heating of while the two faces are pre-cooling such that the sheet is still at a temperature above the softening point of the glass when immédatement chilled by liquid, attenuation before temperature gradients thus established. _AOE280A2AO>

While the sheet falls matrices Glass, the vessel 26 of quenching liquid is lifted by a lift platform 30, to scissoring motion, from the bottom of the pit. The vessel 26 rises to the apex is located just below the bases of the blowing boxes 28, the surface of the quench liquid that it contains being separated by a distance small preset lower nozzles 29 blowing boxes The bent glass sheet, having from the middle to the lateral faces of the temperature gradients established as just 1', expose, immediate is quenched as it passed the spraying zone cold air below the surface of the quench liquid.

The quenching liquid is usually a mineral oil, such as is sold under the trade name deposited " Cylrex FM", and may include a minor amount of additive low-boiling, e.g. jusqû' to 1 O °/ by weight of toluene or carbon tetrachloride.

Penetrating in the liquid of the vessel s * 26,1a glass sheet stops on a frame immersed in the vessel, attached to the base of one of the bins blowing. The clamps open to release the glass sheet on said frame and, after a point in time allowing the sheet to cool in the liquid, the tank descends, and the soaked sheet is removed from the frame and degreased, then inserted into a rack stacking order to completely return to-room temperature.

In another embodiment, the vessel 26 is not, and the glass sheet remains stationary in the frame to cool to the ambient environment in order to to be annealed. A-annealing enclosure can be brought, along a horizontal path, a receiving position of a bent glass sheet hot..

It may be arranged alternately subjecting successive sheets to annealing and quenching, when they descend matrices Glass, to obtain successive pairs of sheets of which one is the other hardened and annealed.

The sheets, heated and cambered in the same conditions and dimensions matching, are very suitable for, be joined for the manufacture of a laminated windshield.

Figures 2 and 3 illustrate in more detail-the structure and operation of the loading station and of the furnace.

The ten first rollers almost vertical 8 of the furnace, are the loading station represented to the right of Figure 2. The rollers are heat-resistant stainless steel and are mounted, at intervals of 20 cm, between upper horizontal longitudinal beams 35 and lower 3 & that extend the support beams of the furnace 1. The spars 35 and 36 of the loading station are connected to a frame comprising a lower cross member ^ and a post that has on the vertical the same inclination, of about 5 °, that the rollers 8 and is supported by struts. The end wall of the furnace located at the loading station is indicated by 39 and an opening 40 access to the furnace, formed through the wall facing the rollers 8, to the base has an enlargement located opposite the lower rollers 13 and for letting the carriage 12 carried by the conveyor into the furnace. Sealing strips asbestos flexible, not shown, are incorporated to the vertical edges of the opening 40 of the furnace.

The side walls 42 and 43 of the furnace carry 4 columns of heating elements 44 and 45 (Figure 3) represented in detail in Figures 6 and 8. The heating elements are directed from each side to the path of the sheets 9 through the furnace and are mounted in groups individually controllable, as exposed.

At loading station (Figure 2), the position of the carriage 12 is defined by a retractable stop 47 against which the ehariot door by its-front end, to slip remains in contact with the rollers driven at a low initial speed; when the stop 47 recedes, the carriage starts to advance from the charging station to the interior of the furnace. A flat glass sheet 9 * cold, loaded on the carriage 12, is supported on the rollers 8 at the loading station. The cold, the sheet is not deformable ^ and it is less need to align strictly the rollers 8 and 13 at the loading station that in the furnace and in the raft container. Therefore, the rollers 8 mounted between the longitudinal members 35 and 36 at the loading station are not angularly adjustable, but mounted in fixed bearings and have on the vertical inclination of the catalyzer, of 5° in the example selected.

The lower ends of the rollers 8 of the loading station are integral with countershafts 48 running from the top to the bottom between the longitudinal members 36, pass through holes drilled in a plate 50, bolted to the bases of the beams 36, and penetrate, below the plate, in bearings self-centering 51, provided one for each roller 8. The bearings 51 have lugs bolted to the plate 50 and the countershafts 48 downwards through the bearings 51.

The tops of the rollers 8 of the loading station are integral with elongated countershafts 53 upwardly projecting between the longitudinal members 35 and are each mounted in a bearing 54 self-centering. The bearings 54 are bolted by ears on a support plate 55, secured on the tops of the longitudinal members 35" Each of the shafts 53, except that of the roll 8 nearest the inlet of the kiln, exceeds the bearing 54 and associated door two pinions 56 twin Galle, 57_AOE280A2AO> The pinions Galle of adjacent rolls are two coupled to two by transmission chains 59*

The idler shaft of the roll 8 elongated 55 nearest the inlet end wall 39 of the furnace is longer than those of the other rollers of the loading station and carries a pinion single Galle 58 and, at its top, a pinion Galle main drive 60, connected by a chain 61 to a pinion Galle 62 mounted to the top of the first one of the rolls of the furnace 8. The rollers 8 of the posted of loading are thereby driven by the same motor group as those forming the remainder of the conveyor, located in the oven.

In the furnace, it is important to finely adjusting the relative orientation of the surfaces of the rollers 8 such that the parts of these surfaces for the sheets a transient support are all contained in a same sheet having, on the vertical, 1' predetermined inclination, for example of 5° " Lour achieved, and as described in the aforementioned application, are mounted rollers 8 of the oven by alternating group of four and three rollers each, the rollers being spaced apart by about 20 cm, and it is arranged to be able to adjust horizontally, perpendicular to the direction of the conveyor, the exact location of the lower levels of each of the groups of adjacent rolls. The tops of the rollers of each set are mounted in a gear box whose position is also adjustable horizontally, perpendicular to the sheet running direction along the conveyor. By adjusting the relative positions of the bearings and gearboxes, can be printed to all rollers 8 of the furnace the angle from vertical.

Each roller 8 of the oven is provided to the base of a shaft-ren-voi 63, mounted in a bearing self-centering 64fixé in a plate 65 carried by sliding blocks tail, dove sliding in guides 67 attached to parallel longitudinal members 68 that extend underneath the floor of the furnace and rest on the shaped webs 6 supporting the floor. The arrangement is shown in the, 3 * figure

Each of the slides dovetail 66 has a end bracket 72, threaded to receive the threaded end of an adjusting shaft^: 74dont the other end passes through a lug drilled positioner, bolted to a spar 76 which extends between the lower ends of the uprights 4situés on one side of the furnace. The end, shaft outer 74est threaded and provided with nuts which flank the catch stop positioner. Each of the plates 65 holding the bearings 64 of a group of rollers has two V-shaped blocks and, by adjusting the two shafts -74, can be adjusted the arrangement of the lower ends of the roller group interested.

the rollers 8 of this group have upper ends reduced diameter and the countershafts elongated 78, (Figure 5) enter a gear box 79 laid 1 'aid of damping mounts on slides dovetail 81 sliding in guides 82 mounted on the tops of the longitudinal members 7le same that the slides of the lower bearings of the rollers, each of the slides 81 has a pierced ear of end 83 and threaded to receive 1-' threaded end of a shaft 'adjustment 85L' other end of the shaft 85 passes through a positioning plate hole 86,87 mounted on a spar which extends along the furnace beneath the sleepers 5L ' outer end of the shaft 85 is threaded and provided with nuts stop 88 on either side of the positioning plate 86.

Each gear boxes 79 rests on two of the runners and, by rotating the associated shafts 85, moving the dovetail slides 81 on the respective sliders, thereby adjusting the positions of the gear box 79 , with respect to those imparted to the bearings 64 the lower ends of the rollers 8,8 to print exactly to the rollers driven by each gear box the desired inclination from vertical. '"

May be adjusted together the positions of the gear box 79 of the various groups of rolls and the plate 65 holding the bearings of the lower ends of the rollers, during initial setting of the furnace, so that all the rollers 8 of the conveyor through the oven be precisely located in the same plane so that all portions of the rollers 8 supporting the sheets have on the vertical has' same inclination, for example of 5°- '

The lower rollers 13 provide a running track by movable carriage 12 which drives the glass sheet through the oven 9, project into the spaces between the rolls almost vertical 8 along the whole length of the conveyer and include an acute angle, of 50° in the example selected, with the rollers 8.

The five rollers 13 which support the. lower carriage 12 at the loading station are shorter than those projecting towards 1' inside in the furnace and extend in a on two spaces between the rollers 8..

the carriage 12 forming the movable support from a sheet of Earth 9 is represented in detail on the figures4 and 5il is of sheet steel bent to have two webs, which are set the same acute angle as the rollers almost vertical 8 with the lower rollers 13La near vertical leg 148, the longer, of the carriage two carrier plates 149, each having an upper edge extended to form a shoulder-_AOE280A2AO> support member 150 whose upper face 151 is coated with refractory anti-slip. The upper face 151 of each shoulder 150 has on its rear edge a projection 152 the width of which determines the minimal offset between the bottom edge 155 of the glass sheet 9 and the support plane defined by the surfaces of the rolls 8 when the cart is in the desired position for conveying a sheet through the oven, its branch 148 bearing against the surfaces of the rolls 8 and its lower leg 154 resting on the lower rollers 13" Figure 5 shows how the upper edge 155 of the glass sheet 8 rests against the rollers when the sheet is loaded at the loading station and Figure 4 shows how the support shoulders reproduce the contour of the sheet of glass to be bent, the contour itself that of the opening of the vehicle to which the sheet is to be incorporated.

Bu in that the rollers 8 and 13 are driven by a same hydraulic motor 103, that suitable choice of gear ratios and that the same degree of frictional contact between the legs 148 and .154 of the carriage and the rollers 8 and 13 respectively, the linear speed of travel of the carriage is always equal to the surface speed of the rollers 8 against which the glass sheet is supported and which give support for upper edge of the sheet.

The carriage also carries at its front end a stop 156 to bear against the retractable stop 47 provided at the loading station, as shown in Figure 2, and to be encountered in travel end a second stop, provided breakage pumphandle 16, once the glass sheet suitably interposed between the matrices Glass. On the carriage. is still mounted, near its front end, a finger 157 for acting on a limit switch SI mounted at the loading station, immediately below the furnace. Another finger 158 is mounted substantially mi-length of the trolley to act, in the furnace, on the actuating member of the other limit switch not shown, incorporated in a control arrangement for adjusting the speed of travel of the carriage in the oven after the glass sheet fully engaged therein.

ELEhENTS CHAÏÏFEimTS DU FOR.

Figure 6 indicates how are mounted electric heating elements indicated at 44 in Figure 5 on the wall 42 of the furnace along the almost vertical back of the rollers 8. Each heating element is a resistive wire 159 wound on a ceramic rod carried by two connection pins 160 extending through the sidewall 42 of the furnace and provide the supply. The heating elements 159 are arranged in a herringbone pattern and connected in series in groups defined by-dotted in Figure 6. For example, the upper group of heating elements encountered first by the glass sheet entering the furnace along the arrow 161 162 is indicated in; it comprises ten® element 159, connected in series as shown in Figure 7 * One end 163 of the series connection is connected to a supply conductor 164. The other conductor. supply, 165, is connected to a thyristor adjustment assembly 166, of conventional structure, which regulates the supply of the group of heating elements 159 are serially mounted in the action of firing pulses applied to the electrodes for triggering the thyristors by conductors tokenized by the driver of ignition pulses 167,168 connected to a circuit start-up pulse generator, also supplied by the conductors 164 and 165.

Adjusting A thermocouple 169 is mounted in the zone of the furnace occupied by the group of heating elements 162. The thermocouple is incorporated into a mounting tempering 170, of conventional structure, and simple controls a switch, , 1' bipolar inverter * 171 which lies against the blocking oscillator of the start-up pulse generator 166 current adjusted either by one, or the other of two potentiometers 172 and 173.

The potentiometers 172 and 173 are adjusted in a known manner to establish high and low levels respectively of energy dissipation in the group of heating elements 162, thereby enabling selection, in accordance with the temperature prevailing in the region of the tower occupied by the group of heating elements 162, detected by the thermocouple 169, a level of power dissipation sometimes high and low, so that the detected temperature maintains a certain set value, attached retort by adjusting a potentiometer d * tempering 170 incorporated into the mounting.

Eight heating elements which are connected in series are arranged in a herringbone pattern in a second group s-substituted 174 to the input end of the kiln, below the group 162. Following The heating elements are divided into two sets of. three groups, each group including nine series and a thermocouple 169 and is fed through a thyristor adjustment assembly under the control of a suitable thermocouple 169 and mounting such tempering as figure · 7

The can individually adjust the operation of each group heating cfêléments by adjusting the setpoint value assigned to the associated mounting tempering. For example, to carry line glass sheet 2 mm thickness at a temperature of moulding 590 °C, reached-approximately evenly throughout the sheet can be assigned for mounting the desired temperature control setpoint values to establish, at the thermocouple 169 of the group of heating elements 162, a temperature of 700°C ' and, at the thermocouple 169 174 of the group, a temperature of 750 °C. Oven the following groups of heating elements, the temperatures at the thermocouples level 169 are 700 °C for the upper groups, for the groups of 725 °C means and 750 °C for the lower groups.

Figure 8 represents the heating elements 45 45 mounted to the side wall of the furnace directed to the-glass sheet to bear against the rollers 8. The glass sheets advance in the direction of the arrow 161, left to the right of the drawing.

The heating elements 159, are wires wound on cores resistant ceramic, such as those shown in Figure 6, and are mounted on connecting pins 160 that pass through the wall 43, they are distributed in groups defined by-dotted and the like grouped shown in Figure 6, but with the addition of a further group of elements 177 each having a thermocouple control 176. The additional group is formed by a row of six heating elements which border the base of the side wall 43 of the furnace the longer, ate immédi member over the apertures d ' ^ extraction of cullet.

Each group of elements, is controlled by a thyristor adjustment assembly of the genus represented on the figüre 7i simple inverter comprising an arrangement. The. temperature maintained in the thermocouples 1? S is 700° to the higher of the two groups located at the input end of the kiln, and ? 50° G for the lower group when holding a sheet of glass 2 mm thickness at 590° G for bending as indicated above. The_% temperatures maintained in the thermocouples are 178, the bottom row of heating elements 177₅ of 750 °C and, for the groups upper, and lower means of. additional ensemblés arranged as shown example, of 700 and 750 °C.

Figure 3 represents an alternative arrangement of the means indicated in groups and lower 44a, 44b and 45a, 45b. Lu in that the groups lower 44b and 45b are very close to each other and the groups means 44a and 45a somewhat closely adjacent glass, a temperature gradient is established from top to bottom in each sheet, whose bottom edge is point higher than that of the upper edge-

The control mode of the speed at which the carriage carrying a glass sheet passes through the oven is described in British Patent above.

Figure 5 shows how the upper edge of the glass sheet rests countered the support rollers 8 almost vertical when the cold glass sheet 9 is loaded on the support carriage 12 at the loading station and during the initial stage of heating the glass. As the sheet is heated during passing through the oven and the temperature approach, of 580 to 660 °C, that is to be, it softens enough to collapse against the rollers 8. support and would undergo an unallowable deformation if it remained too long at this temperature.

Initially, the top collapses against the rollers 8 and the support surface offered spoken rollers 8 must always extend far down, from the upper edge of the sheet, to allow the permissible deformation..

Is adjusted a timer incorporated in the control arrangement of the roller drive so that the glass sheet has reached the desired temperature, which, in one embodiment, is approximately uniform throughout and throughout its thickness, when the particle is accelerated to the output of the furnace into the raft container, before the deformation undergone by the sheet by initial collapse tie its upper part against the rollers 8, optionally followed by a bulge of the bottom portion of the sheet, from exceeding the allowable limit value.

May be adjusted the kiln temperatures as indicated in the table 1 below

For any mean temperature of the furnace, the time for a sheet to achieve the desired final temperature depends on 1' thickness of the sheet and description in the application of detailed examples for implementing relating to lenses of 2.2 to 15 mm thickness and heating time required to print the glass with final temperature of 580 to 700° G..

The raft container 17, shown in Figures 9, and 10B 10A, defines a chamber that contains the matrices to be bent and comprises the inlet end wall 248, a discharge end wall and a roof 255 254, having a recess 255qui leads to the top of the inlet wall. 248 and a recess 256 which leads to the top of the outlet wall 255 * Variations in the depth of each recess according to the setting imparted to the. lifting mechanism in order to accommodate glass sheets of different heights, as exposed figures 12 and has about 15-

The case "pumphandle also has rear walls 257 and before 258 and floor sections, one, 259, hand toward the rear of the base of the front wall 258 and the other, 260, hand toward the front of the base of the rear wall 257"

An opening elongated vertical input to the chamber is provided in the inlet wall 248 262 and an outlet opening, provided in the wall of sortie253_} allows the carriage 12 of backing out once the glass sheet Glass lifted from the carriage and in bending between the dies. The output 262 leads to the conveyor 8 extension indicated at left of Figure 1.

The roof 254 is suspended by tie rods 264 to a support structure comprising a crosspiece 265 extending between columns 266.

The floor sections 259 and 260 rest on joists 267 and 268 and define between them, to the base of the chamber, an opening 269 which can be lowered by a bent glass sheet. The walls, the roof and the floor sections of the. box are joined to form a steel shell provided with a refractory lining.

The chamber defined by the raft container 17 is brought to the same temperature as the glass sheet from the furnace in said plastic housing, so that the dies Glass held in the receptacle are at the same temperature as the ambient medium and thus at substantially the same temperature as the glass sheet entering the raft container. The raft container is heated internally by gas burners indicated at 270, connected via conduits to inlet slots 27ΐ provided in the front walls 257 and 258 rear of the body. 11 is provided four burners 270 271 supplied to four slots, provided with two within each of the front and rear walls and each burner is controlled by a thermocouple mounted in the male die, as close as possible to the face bending, so that the bending temperature, of 580 to 650 °C and 610 °C for example, prevailing in read raft container remains as uniform as possible. The ' burners 270 are connected by flexible tubes to gas supply conduits and combustion air, comprising means controlled by the thermocouple incorporated into the male die to vary the proportions of the air/gas mixture sent to the burners.

The " burners, to-gas generated in the raft container a positive pressure hot gas and these 'flow from top to bottom through 1' lower opening of a case, meets. ascending gas. The level of equilibrium of the pressures is usually located immediately below the additional heating devices 27"

The solid oscillating frame, indicated at 20' in Figure 1, on which is mounted the raft container has bars 272 and 273 of the longitudinal members welded to the ends of the cross members 272.

Each passes through 272 is supported on a lug joint 274-, to which it is welded, articulated to a 275 trunnions mounted in bearings 276 resting on a bottom support plate 277 which covers the upper face of cornice uhe 278 cut into the side walls of the pit. The oscillating frame and 1' entire raft container and associated hardware that it carries around the trunnions 275 have a balance such that the frame 272,273 can easily switch from a horizontal position in the position shown in Figure 10, inclined at about 5° to the horizontal.

Sills 279 and 280 extend above the oscillating frame between the cross members 272, on ' which they are mounted by end supports 281.

A spar 282 is directly supported by the cross members 272 of the oscillating frame^y the joists and supports 267-

A left, in Figure 10, the oscillating frame, a plate 283 is supported by spacers. the spar 273La 284sur thickness plate 283, short, is mounted at the centre of the beam end 273 and connected by stiffening profiles to the spar 279-

Above the plated and 279 283 of the spar, two parallel support beams 286 are respectively mounted by of the support tabs 287 and 288 on. the plate 279 and 283 on the beam. The parallel joists 286 carry a 289 for manoeuvring the male die 16, carried by a die holder 291.

Also, to 1' of m is right of the oscillating frame, a middle plate 292 is mounted with. of support tabs 293 on the upper side of the spar 273La 292.est end plate fixed by stiffening profiles 294qui connect at 280 the spar;

two parallel poutrelies 296 of a batch 297 for manoeuvring the female die 15 are mounted on the spar and 280 on the plate 292 by of the support tabs 298 and 299-

The female die 15 is mounted on a support matrix ' 300, carried by the operating group 297_AOE280A2AO>

The oscillating frame 272,273 lever under the effect of a single hydraulic jack 301 (figure 10A), articulated on trunnions 302 303 in a fork secured to a joist 304 along a longitudinal side of the pit. The actuator 301 has a piston rod 305 directed-to the top and having a head that supports a journal 306 307 309 hinged in a clevis attached lower on mi-height at the centre of the beam end 273 _AOE280A2AO>

The horizontal position and the degree of inclination of the oscillating frame sont_réglables by means of stop shown in Figure 12. Near each end of the spar end 273 carrying the cylinder 305 are fixed in this side member, of the U-shaped legs 310, each of which is welded to the longerqn and reinforced-gussets. A locking lug 311, rectangular cross-section, is housed in each U-lug and mounted on the fixed beam 304' e to the longitudinal wall of the pit; a second stopper 311 is mounted on the beam 304 below the U-shaped tab The bolts adjustable stop are attached to the bight of the U-lug, from which they emanate respectively from up and down to bear against the lugs 311 *-By adjusting the adjusting bolts is ensured the horizontality of the oscillating frame non-tilted and adjust the tilt is taken by the oscillating frame in position, tilted to cause the almost vertical rollers 8 of the raft container 17 precisely aligned in the same plane as the rollers 8 of the furnace, for receiving a hot glass sheet Glass.

Spar 273 The other end of the oscillating frame is provided at each end with a hydraulic damper 314 whose piston rod bears against the cornice 278 along the long sides of the pit. The dampers stabilize the oscillating frame at the end of its stroke of inclination.

On the oscillating frame is also mounted a support structure indicated by 315, for supporting the gas burners 270.

The rollers 8,13 and 18 of the raft container 17 are driven by the same transmission that the rollers the furnace from the hydraulic motor 103. The rollers almost vertical 8 and 18 are driven at their apices by gearboxes. 317 (figures 9 and 10) having the same structure as the boxes d '' gear 79 which drive the-rollers 8 of the furnace. The gearboxes 317 are mounted above beams 318, attached between the sleepers 265" on which they are adjustable by "means of sliding blocks in V in the same manner as the" gearboxes 79 of the furnace.

The movement is-transmitted to the " gearboxes 317 319 by-a shaft via a universal joint to an intermediate shaft 320 321, itself coupled by an articulated joint 322 to the output shaft 323 of a shaft transmission orthogonal 324 mounted on 1' one of the columns 266. The transmission 324 receives the movement, through an articulated joint 325, of a transmission shaft 326, mounted in bearings 32? carried by the column 266 and which 1' lower end is coupled by an articulated joint 328 to another transmission shaft mounted on the orthogonal beam 280.

Each of the rollers almost vertical 8 and 18 of the raft container present to the base a countershaft 330 mounted in a bearing self-centering 331 fixed to a plate 332 carried by L-shaped brackets, in one of which is represented in 333" on the ends of beams leaving 334 of the core of the Iongeron 280. The plate 332 is adjustable laterally with respect to the L-shaped brackets 333L ' free end of each beam cantilever 334 and supported by a stay not shown, extending upwardly therefrom a spar, deleted in the drawing for. clarity, which connects the two end webs 272 of the oscillating frame. The beam also supports the joists 268 carrying the floor section 260 of the raft container.

A closed section 336,334 transverse to the beams, is mounted on the upper faces thereof. It constitutes a support on which are mounted the short lower rollers 13 and the transmissions serving.

May be adjusted both the inclination of the short rollers 13 relative to the rollers 8 18 almost vertical and that the extent to which these rollers 13 project between the rollers 8 and 18 in the manner described about the rollers 13 of the furnace. The movement is transmitted to a short lower ruuleaux 13 by a shaft 338, parallel to the closed section 536 and mounted in bearings carried by brackets attached to the beam. The movement is transmitted from the shaft 338 to the rollers 19 by transmissions orthogonal shaft 339, also mounted by supports bent on the closed section 336. Each transmission 339 drives the roller 19 with the aid of an intermediate shaft 340, itself driving via a second joint 341, a harmonic drive orthogonal 3^-2 34-3 which drives a shaft on which is mounted 1 'end of the roll 13* L' 34-3 shaft passes through a cylindrical bearing 34-4 whose body is integral with sleeves 345 bolted to an adjustable mount.

The shaft 338 is driven from the gear box ' lower 119 that drives the rollers 13 located at the outlet end of the furnace near the raft container 17Un not shown conventional articulated joint couples the output shaft of the lower gear case 119 with the end of the shaft 338 positioned adjacent to the outlet of the furnace. The other end of the shaft 338 is coupled via a mechanism to orthogonal shafts and a universal joint to the input shaft of the transmission 329, thereby ensuring the roller drive 18 via the gearboxes 317-

The group 297 for manoeuvring the matrix comprising two parallel transverse box girders 400, joined near their ends by spacers secured beneath them. The upper face of each support beam is provided with two rails

flat 405, each tether over a certain distance, the face

296 ,

upper joist/thereof near the ends thereof. 405 On the rails move skates ball bearing, attached to the sides of the beams by gussets 400 407. The runners carry the box girders 400 and the support. 300 of the female die on the main girders 296 .

On a plate 422 attached to the side of one of the support beams 296 are mounted four contactors limit S9, S10, and S12 SU, offset relative to one another perpendicular to the plate 422 so as to be actuated in the desired order by fingers fixed below a plate 423 424, cantilevered on the side of one of the box girders 400.

The contactors and their operating fingers are positioned to give the following instructions:

S9; female die being recoil

S10; female die at the end of advance

SU: female die advancing

S12: female die at the end of recoil.

rAT - RICi LALB -

The matrix mixed with 16 291 is mounted on a support, itself mounted on a group^& of/S_AOUNI167AO> t the structure being similar to that of the support and the. group operating the female die.

Figure 11 is a-detailed view of the structure of the male die, that includes a face continuous active 490 of sheet steel having perforations indicated in 491 and coated with refractory to bear against one side of the hot glass sheet " knob against it even the frame skeleton the female die. The active face 490 is mounted on a profile frame 492 connected to a supporting frame by adjustable mounts 493 known kind indicated in 494.

495 A inner wall is mounted on struts 493 the inner frame and its upper edge is connected to the chassis by a flexible joint 492 · On the frame 497 493 498 is sealed a back plate with a depression for receiving pneumatic conduits 499 which lead into a chamber defined by the active surface 490,495 the inner wall and the back plate 498 and projecting from a manifold 500 connected, across a valve 501,502 to a pressure line and, across a valve 503, to a conduit under vacuum 504Le flexible seal 497 adjusts la_ position of the active face 490 493 relative to the frame-

Lu opening, the valve 503 connects the inner chamber of the matrix to the pipe depression, thereby helping maintain, by suction through the perforations 491 of the active side, a sheet being bending against the surface of the matrix.

When the bending is completed, co mm e is exposed, and the tap closed 503,1 ' opening valve 501 transmits a puff of air through the perforations 491, which contributes to detach the bent glass sheet of the surface of the male die when the matrices separate.

A supporting stand 510 is attached to the bottom plate 498, matrices in the chamber near the base of the matrix, and carries electric heating elements, indicated at 511 and also shown in Figure 10A, for heating the lower part of the matrix when the face 490 of the male dies must have from top to bottom a temperature gradient concordant with that already printed to the sheet while passing through the oven by means of the heating elements 44a, 44b and 45a, 45b according to the-embodiment, shown in Figure 5. The elements 511 are alimontés by connections through a backside of the die, in a conventional manner.

The back plate 498 of the male die is suspended from the main die holder using an arrangement of adjustment and by clamping and movement " angularly about a horizontal axis substantially perpendicular to the back plate 498 from the die is possible in that the fixture 291 of the male die has an adjustable coupling with the operating group 289 of the male die.

Contactors limit Two S13 and S14 are mounted on a plate 506 (figure 10A), secured to the joists 286 câté a support group for manoeuvring the male die. These contactors are operated by fingers fixed below a plate 507, cantilevered on the câté of one of the box girders of the operating group 400 of the male die. The contactors and fingers are located to provide the following instructions:

S13: male die being recoil

S14: male die at the end of the advance.

The bar gripper holding 23, from which there are suspended clips 22, and the lift mechanism having the bar is suspended are represented in more detail in Figures 12 and 13.

Each of the clamps 22 may be superimposed exactly to the upper edge of the bent glass sheet ' between the matrices before it closes on the upper edge and is mounted with clearance. in a hinge joint clamp described in detail in the above-mentioned request, mounted on a vertical spindle attached directly or cantilevered to the bar.

The bar gripper holding 23, straight, is suspended from two groups de_AOE280A2AO> lifting, each mounted on a suspended beam 570,571 carried by columns and which overlaps the raft container as shown in Figure 12. A lifting gear is provided at each end of the bar 23 and each of these groups comprises-a framework fixed upper superstructure 572 forming a cuboid louver which comprises vertical beams, transverse supports and a stick 575 concerning its upper side a fixed carrier 574 wherein the bottom of a hydraulic cylinder, and 575a 575h respectively, is articulated by an axis 576. The shaft 577 of the sliding piston in the cylinder passes through 575 has from top to the bottom of cylinder and is articulated in 578 on. Fortes ears 579 580 attached to the stock of a moveable frame louver 581,. also cuboid, which moves vertically into the framework fixed upper 572 by the action of the ram 575La moving frame is fixed to vertical slides 581a sliding in bearings embedded in the ears of the upper framework 572a 572.

The piston rod spring 577 582 the top of the cylinder and bears at its upper end a actuator 583 contactors which acts on two contactors S16 and S17 limit when the piston of the jack 575 stroke reaches its high and low, causing the framework 581 to the up and down in the fixed framework 572.

581 The moving frame comprises a base on which are mounted horizontal 586 chairs 587 carrier carrying a shaft provided with two reel drums 588 589 590 and having therewith a slip coupling.

Brake disc 591 also journalled on the shaft and on the brake arms 592 by clamping, fixed to a bracket mounted on 1 'base 586, enclosing the disc 591 for' . braking the drums as the lifting is exposed.

Below the moving frame 581 is attached a lower frame, designated by the general reference 593, comprising four suspension beams 594qui extend to the bottom of a frame 581 595 of the frame. The base of each beam 594est 596 secured to a base. Four beams 59A It is provided, each secured in a corner of the upper frame and 1 595' 596 base.

597 Two rods, whose lower sections are threaded

in 598, connect the 595 and 596 the base frame, to which they are attached. 597 The rods carry a middle stand formed of two posts ' 599 joined at their apices by a handle 600 and at their bases by a cross member 601. The middle stand is mounted on the rods pure 597 ears 602 provided at the ends of the handle and are coated bearing 600. The ears 602 carry the middle stand on the rods 597 with a freedom of vertical movement. 603 Other ears are attached to the lower ends of the uprights and 599 adjustable by means of nuts 604sur the rods threaded sections 598 597-

The nuts 604 allow vertically adjust the middle stand relative to the frame 593 suspended below the moving frame 581.

The middle stand carries two guide tubes guiding of the hoisting ropes 606 607 and 608 that wind up on the drums lifting 589 and 590 respectively. The two cables 607 and 608 609 bypass of the deflection rollers mounted on pins 610 carried by a mounting bar suspended by tabs 612 611 below the moving frame 581. The two deflection rollers 609 are offset relative to one another as shown in Figure 13B. The two tubes 606 have a like offset, to carry at their lower ends to the top of the bar gripper holding 23, one near the rear edge and the other near the edge avantde the bar. The câtxte 607 are connected to the front edge and the cables 608 the rear edge of the bar 23.

The figure 13B shows how the tops of the guide tubes 606 are attached to the crossbeam 601 of the middle stand. The tops of the tubes 606 pass through holes drilled in that crossbeam 601 and are secured thereto by captive nuts. The tubes 606-mapping.

provide pads, not shown, fixed ' in the base 598 of the moving frame 593, allowing them to move vertically in the meat... realization move when the ears rule 603 on the rods 597Ainsi, can be vertically adjust the middle stand and the guide tubes 606 by winding or stepping down the bar 23 for the treatment of glass sheets of different heights. The also sets the depth of the recesses 255,256 of the roof of the raft container, based on the settings of the lifting groups as described for Figure 16.

Drums The shaft 588 589 590 and lifting the figure 12A is connected by a connection shaft toggle joint 615 with a hydraulic drive motor 616, mounted on the cross member 570 of the upper support frame. The shaft 588, extended, extends over the beam 570. lifting group to the right, where it rests in other pads 587 and where it is secured of reel drums 589 and 590 of the group of right lifting of the bar 23, identical in all respects to the group of left lifting.

The guide tubes 606, heat-resistant stainless steel downwards through glands 617 incorporated into the roof of the body 261 'pumphandle and define the position of the top of the bar 23, suspended in the body by the cables 607 basolante' and 608.

In the position shown, the pistons are retracted into the cylinders 575, so that the mobile framework 581, in upper positions, are retracted upwardly dahs the fixed framework and 607.et 608 572 that the cables are wound on the drums and 589' 590, causing the top of the bar 23 against the lower ends of the tubes 606, themselves in upper positions.

The lower sections of the hoisting ropes 607 et.608 are engaged in sleeves 620, housed in bearings inserted into the upper and lower ends of the tubes 606. The bar 23 is attached to the lower ends of the sleeves and 620, when it is retracted upwardly as represented, the tops of the sleeves 620. emerge at the top of the tubes 606.

The the 23 represented in its upper position is assisted by a roller 62l provided on the back of the bar 23 and engaged in a guide track 622 suspended through the roof of the structure to the upper beam 570 pumphandle"

When Isjbarre 23 are retracted upward as shown, the jaws of the clamps 22 are spaced above the upper edge of the matrices Glass. For lowering the bar 23 to

-engage the jaws of the clamps on the upper edge of a bent glass sheet held between the dies, are allowed to act simultaneously the two jacks 575 to press the mobile framework 581 and 593 downwardly, the bar 23 remaining clamped against the bases of the guide tubes 606 by the hoisting ropes 607 and 608. The assembly of the lifting arrangement moves downwards to place the bar 23 to such a level that the open jaws of the grippers are engaged on the upper edge of the bent glass sheet held between the dies.

The clamps occupy, on the bar 23 which carries them, the desired positions for lowering into the spaces between the sections of the frame of the apertured female die (Figure 9) and in corresponding notches, for the receiving, in the upper edge of the dome die male. During descent of the bar 23, the clamps are guided to overlap exactly to the upper edge of the glass sheet.

The guide tubes through which the cables 607 606 and 60S are represented in detail in Figures, 13B and 13C. The sleeve 620 pushed onto 1' end of the cable passes through a pad 607 623 welded in the top of the guide tube 606 and a contoured profile $24 housed in the base of the tube.

The base of the sleeve 620 is welded to an adapter top planar 626 resting on the upper face of a plate 628 incorporated to the bar 23 and provided on its upper side with a semi-cylindrical boss 626a. 607 The end of the cable protruding from the base of the sleeve the 620.traverse⁴ 628 a plate and lower plate placed under the plate 627. A ferrule is welded to the lower end of the cable, below the adapter 627.

The pad 624 has in its base a V-shaped notch 629 that receives the semi-cylindrical boss of the adapter the -626a, 626 607 périeur when the cable is tensioned, clamping the plate 628 of the bar 23 against the bases of the guide tubes.

A push rod 63 $is accommodated in the guide tube 606 and passes through a vertical hole drilled in the bushing 624. 631 Its pointed lower end rests on the top face of the adapter 626 when the bar 23 is pulled against the guide tubes. The top of the push rod is guided in the tube 630 606 632 by an ear and the rod 630 door, secured. near its apex, an actuating arm 633 634 radial passing through a slot provided in the wall of the tube 606. 635 An adjustable screw carried by the ' 633 arm acts on a switch S18 pressure mounted on a bracket 637 to the outside of the tube 606. When 23 occupies the raised position represented, the rod 63O, pushed upwards,⁴ moves the screw 635 of the contactor S18. When 23 descends relative to the guide tube 606, the lower support of the pointed end of litigation 630 631 also descends, the rod is pulled down by a spring connecting the arm 633 638 to 1' bracket 637 and the contactor S18, operated, signals that the bar 23 descends well during unwinding cables 607 and 608.

The other guide tube 606, through which is threaded the cable 608,639 carries a different profile, fixed in its lower end that it projects and that not the members in a V, but an abutment face 640 flat bottom against which the flat top face of the adapter 626 628 door when the plate of the bar 23 is pulled up against the lower ends of the guide tubes. The plate 627, which secures the base of the cable 608 to the front edge of the plate 628 of the bar 23, includes a strain relief clamped to the end of the cable 608 below the bar 23On can adjust the cable clamp. on the cable for adjusting the inclination of -23 bar to the horizontal, to pivot around the semi-cylindrical boss 626a of 1' adapter 626, to accurately adjust the bar 23 during initial setting of the lifting mechanism.

Bes movement. of descent of the bar 23 are stabilized and guided by two wires 64-5Le 64-5 top of each wire is held in a wire clamp 64-6 (figure 13B) attached to a bottom member of frame fixed upper 64-7 read. The guide wires 64-5 vertically pass through the raft container and run to the has the sides of the pit- jacenteA the basis of the pit, 1' lower end of each wire passes 64-5 sound a guide pulley not shown, integral with a handcuff fitted to the stem of a hydraulic cylinder holding the wire 64-5 in the desired voltage.

A each of the top plates 628 at the ends

-of the bar 23 are fixed two rollers 64-9 parallel to the bar 23. The guide wires 64-5 pass therebetween. Pairs of rollers like 650 passed by the '-wire 64-5 are mounted on a transverse plate 651 welded between the lower ends of the two side plates 64-1 of the bracket.

^ At the both ends of the bar 23 are welded to the side plates 64-1, near their lower ends, lateral extension plates 652, which extend inwardly into the interior of the bar 23 and carry an axis 653 on which pivots a frame having two side arms 654-, articulated on the ends of the axis 653 that exceed the outside of the ends of the extension plates. 652. One of the side arms 654-1-has to ' rear an extension provided with a pallet 655 for tilting the frame under the action of a push rod. The arms '654 are joined, at their outer ends, by bolts 656, to each of which is fixed perpendicularly, at 1' axis 653, the one of the two plates b > 57, upwardly directed, whose apices are connected by a. rod bearing 659 660 cable ties which are clamped in the ends of three operating cable 661 which open and close three clamps. Therefore, three clamps are operated from each end of the bar 23.

Each clip preferably has a structure such that its jaws close under the effect of a sliding weight which is incorporated.

Each vane or rapper 655 is encountered by a push rod sliding 662, as shown in Figure 12, in a frame 663 attached à.l' one of the legs 594 below a pneumatic cylinder 664,594 attached to the post and whose piston rod 665, directed to the has, sunk into the extended position the push rod 662 to 655 meet the pallet and pivot the arms 654 to tension the cables 6611 and open the jaws.

A pallet or encounters a rapper 666 cohtacteur limit 665 S19 when the rod retracts in the cylinder and that the clamp jaws close. Two push rod arrangements identical are provided at opposite ends of the bar 23 and each comprise a, pneumatic cylinder 664 and an end position switch S19.

On the rod 23 are also mounted, near each of its ends, tabs 667 downwardly directed, wafer-carrying square metal 668 for the photoelectric detection of the level reached by the bar 23 in descending below the raft container.

Six clamps 22 are suspended from the bar 23, each by a.

suspension structure such that, while a bent glass sheet is held between the dies, the bar 23 descends, the clips being arranged so that their open jaws overlapped with a rigorous symmetry the upper edge of the sheet.

Each of the clips 22 located outermost is suspended in a hinge clamp carrier articulated on an arm 670 cantilevered perpendicular to the rod 23, thus shifting the joint the level of said bar toward the male die. The two clamps following 22, inwardly, are suspended in hinges which the pins are directly connected to the bar 23. The clamps 22 located at the-compulsive-_AOE280A2AO> to are suspended in hinges hinged at the ends of arms 672. cantilevered perpendicular to the bar 23 and directed back and the female die.

The grip-guide are provided to cause each clip in position such that its jaws overlapped with a rigorous symmetry the " upper edge that the glass sheet, when the bar gripper carrier 23 is in the lower position. When 23 reaches its bottom position corresponding to the low ends of travel of the pistons of the jacks 576, the cables ' 661 are released and the jaws close on the glass sheet. -

The matrices Glass male and female, brought to the temperature prevailing in the raft container that * is maintained and so close as possible to that of the glass sheet from the furnace, remain joined follows the glass sheet for a time, for example seconds dejcinq, during which incorporates a strain relief printed by bending the sheet and damping of the temperature differences existing in the sheet, due to contact of the foil with the matrices Glass chaudesQuand the clamps grip the upper edge of the glass sheet, the lifting pins descend, recoil of the female die is primer and the bent glass sheet, suspended from the clips, stays in contact with the continuous surface of the matrix supplied.

The valve 501 (Figure 11) opens and a burst of air emitted through the perforations of the male die 491 releases the foil convex the surface of the matrix, and the recoil of the male die is primer,

The bent glass sheet is. then freely suspended vertically to the clamps and its descent for the treatment according to s ' primer. The raft container starts its return movement back in an inclined position where it is ready to receive the sheet following Glass the male and female dies and complete their return stroke-

On APPOINT GHàUffffiGE

The temperature reached by the glass sheet during pass through the oven, , time related during which the sheet can be heated in the furnace without unallowable deformation being clogged almost vertical against the rollers of the furnace, is also that of bending of the sheet, of 550 to 650 °C, for example. of 610 °C, and of the bent glass sheet released by the dies to be bent and suspended by the grippers in the raft container.

Or, it is often desirable, in particular for obtaining a, sheet high strength glass, that the initial temperature is greater than cëlle quenching. bending and reaches, for example, 680 °C; accordingly, before the quenching by immersion in the liquid in the tank 26, is scrolled sheet, during its descent, between.

heating complementary the carry at a higher temperature, from which it undergoes a preliminary surface cooling prior to dipping in the quenching liquid.

After bending of the sheet, the piston rods 577 575 cylinders lifting groups pass in downward extension ' for carrying the mobile framework 593 in positions low limits with respect to the; upper framework fixed, the. bar 23 moves even, during further processing of the sheet, under the action of the hoisting motor 616 that drives, via the articulated shaft 615, the shaft and the reel drums 588 589 and 590 for unwinding the cables 607 and 608 which. are suspended both ends of léÇbarre 23. The bar 23 begins to descend vertically along the guidelines 64-5 and the sheet is conveyed between the two sets of heating elements 27 of extra (figure 1) represented in detail in Figure 14 -.

The tops of the heating assemblies are located at about 60 cm below the lower edges of the matrices and the heating assemblies have 90 cm high.

Each heating element assembly includes a refractor panel 790 carrying a series of heating elements 27. The panels 790 form the walls of an elongated chamber which has an inlet opening 791, below the outlet opening 269 of the raft container. Curtains sealing The asbestos 792, suspended from the sides of the elongated outlet 269, are applied against the members defining the inlet 791 of the extra heating chamber. The refractory panels are vertically fixed and the curtains flexible 792 seal between the output 269 of the raft container and the fixed entry 791 - '.

Each refractory panel includes a support structure 27 793Les metal heating elements are of the wires wound around ceramic tubes mounted on spindles connection 794-, steel, secured in the panels and 790 mounted in-isolators 795 held by the support structure 793 metal^N -

The Heating of extra elements 27 are heated to be at a temperature of between 750 and 1600 °C, for example 1000 to 1200° G. Its climbing down between these elements, the sheet fallen may be heated at temperature. upper, G of 60° or more, than that at which it leaves the dies Glass; for example, a warped sheet to 620 °C can be used during the quenching 68G°C.

If the sheet falls uniform velocity between the heating elements, it is heated to approximately uniformly throughout its thickness. It may have a temperature somewhat higher in the surface region than therein but, at worst, this difference of temperature is about 12° G.

Alternatively and to further heat the lower edge than the upper edge of the glass sheet, can be imparted to the latter, when its lower edge achieved for instance opposite the bases of the heating panels, acceleration line passing its rate of descent by the lifting groups of 150 to 300 mm/s. Therefore, the top having a Heating shorter between the heating panels and each part of the sheet is heated so that there is substantially no temperature gradient through the thickness or possible that the gradient is at most 12 °C as noted below, but to provide a linear temperature gradient between the lower edge of the sheet, for example heated to 700° G, and the upper edge, for example heated to 680 °C, during. that it progresses between the bases of the failure to the heating to a stage where it undergoes a pre-cooling before being dipped into the oil tank 26.

The control equipment that are to describe programs the rate at which the lifting motor 616 operates between its starting and the immobilization of the glass sheet in the quench vessel.

Can be obtained maximum descending speed of 100 cm/s and various speeds are below-mentioned example.

The table IX indicates in detail, example, sets of operating conditions: temperature for bending the sheet, time during which the sheet is to reside between the heating elements to reach the temperature of the pre-quench and desired rate of descent to be adopted for obtaining this temperature.

page see table IX:3S

Other examples of operating conditions are given in tables X, XI and XII which illustrate obtaining a linear temperature gradient of 10 to 30 °C between the lower edge and the least hot upper edge of the sheet. The data relates to a glass sheet 25 cm high falls between sets of heating elements 27 of 90 cm high. the sheet is accelerated from the initial speed to the final speed when its lower edge reaches the base of the furnace * The rate of descent indicates the approximate time of residence of the upper and lower edges of the sheet between the heating elements.

Toir page table X:40

page table XI:41

page table XII: 42

Blowing Two elongated boxes 28 extend continuously of the pit located under the Heating of extra elements.

Each pontoon 28,29 having nozzles projecting on its front face, is mounted on wheels 800 side (Figure 15) rolling on races 801 along the large wall of the tank. It is connected by a conduit to a centrifugal fan 802 805 mounted near one of the small wall of the tank and transmits individually under a pressure equivalent to a water column of 38 cm, 3.7 XPa is. The wheels 800 are those of carriages to which are mounted the blowing boxes and the ducts which serve the and which can be advanced and retracted the crush boxes 801 on the paths for regulating the distance between the ends dice nozzles 29 of the route taken by the bent glass sheet hot downwardly through the base of the chamber additional heating. The distance is usually 10.5 cm. The front faces of the blowing boxes 28 may be flat as. represented or have a curvature that substantially matches that of the curved sheets to which the boxes " should give by projecting cool air a pre-cooling.

The faces activated boxes have, in a specific example, 22 cm high. The nozzles have openings for 3 mm of diameter and are distributed staggered with a pitch of 18 mm. The nozzles located on either side of the path of the sheet are offset relative to each other so as not to be Glass thickness 2.0 mm

XI

XII

coaxial.

At carriage of the box 28 located to the right of the drawing 15 is attached a frame suspended 806 provided at the base of support pads 807 on which falls the hot glass sheet. S * The pads extend across the path of descent of the sheet and are stabilized by depending legs 808 is fixed by fastening the path 801 after the box 28. in the desired position. The frame 806 and 808 the depending legs are long enough to that, when the sheet rests with its lower edge in the pads 807, its upper edge located immediately below the lower nozzles blowing boxes.

The air supply cold boxes 28 is adjusted so that the faces of the sheet are cooled Heating of extra e.g. 50 °C without the centre of the sheet falls appreciably below the temperature of the pre-quench extra printed by heating. Therefore, temperature gradients of about 50 °C exist between the medium and the faces of the sheet when it leaves the atmosphere of cold air projected by the nozzles 29 to be immediately immersed in the quench vessel 26.

Quenching The vessel 26 and curing is shown diagrammatically in Figure 15 and contains a mass of quenching liquid such as 0 to 240°. The vessel 26 is carried by a table 810, resting on a platform 30 qni is the top plate of a lifting table to scissoring motion. The table, hydraulically operated, lifts the quench vessel 26 at a time the cycling of the matrices Glass as the vessel 26 is stopped in high position, immediately underlying the blowing boxes 28, before the glass sheet falls therebetween in, the quenching liquid that it contains. The the frame 806 and the pads 807 are completely submerged in the quench liquid before the sheet enters the vessel.

II any sharply define the level reached by the surface of the quenching liquid, with the nozzles lower blowing boxes 28, to minimize the attenuation of the temperature gradients established in 1' to the thickness of the glass^T stage pre-cooling before quenching side of the sheet by contact with the quench liquid. The The are temperature gradients existing in the thickness of the sheet when the medium thereof breaks cooling the strain point of the glass which determine the occurrence in the sheet, in the return to ambient temperature, desired constraints, surface compressive and the medium, the sheet.

For that the level reached by the surface of the quenching liquid is located at a distance strictly defined, for example 2.5 cm, below the blowing boxes 28, the quenching liquid continuously flows from below a weir mounted in the upper part of the vessel 26.

At the desired point in time of the operating cycle, the platform 30 is lifted to cause the quench vessel 26 in a raised position receiving a hot glass sheet. The vessel die quenching remains in this position, the hot sheet based on the pads 807, for example for a time of 20 seconds, so that the sheet returns wholly very below the strain point before the platform ^ reducing, diverges downward the vessel for quenching the shaped sheet, indicated by 856 in Figure 15, which remains supported by the pads 807.

During quenching, as soon as the glass sheet is fully immersed in the quenching liquid and is supported by its lower edge on the pads 807 856, the clamps sbnt opened by the action of actuating means, provided in the pit, on the pallets 655 (Figure 12), which draws the cables operating clamps; they rise then, with the bar gripper holding 23, under the action of the lifting mechanism, so that the bar 23 has passed upwardly the dies before they meet at the sheet following Glass.

After descent of the quench vessel, the sheet is transferred manually bent in a degreasing tank, and then returns after degreasing at room temperature.

For the construction of a series of curved sheets and annealed, is allowed to the quench vessel 26 in the lower position, and stops the feed of the heating section and of sending extra air to the pre-chill section.

The frame 806 is mounted in a chamber annealing horizontal displacement from the desired position to receive each of the successive sheets through from top to bottom the extra secinactives for heating and pre-cooling.

The " frame is provided with damper springs for receiving a moving sheet of the maximum speed and non-slowed liquid immersion of trempeLes pads 807 of the rack bear unegarniture greater thermal insulation.

Each of the successive sheets rests on the pads 807 during annealing it in the enclosure, such that once cooled, it has only relatively low stresses, for example represented by a middle stress pulling MU 7/m2. Once the cooled sheet, annealing the enclosure deviates horizontally, the annealed sheet is extracted from the frame and the-annealing enclosure returns surround the frame, ready to receive the next sheet.

In some cases, is produced alternately a sheet and annealed a soaked sheet, for example when the sheets are to be stacked to form a laminated windshield. The _AOE280A2AO> Heating of extra sections and pre-cooling houses active. Until Glass the dies separate, the two sheets have undergone thermal cycling identical and have curvatures matching to be combined to form a laminated glazing. Preserve cetteconcordance It is curvatures during further processing. The mode of producing the result is described in British Patent above.

The indices of global deformation of the sheets also hardened and tempered match when treating these sheets to have a temperature gradient oriented from top to bottom by taking into account the étatatteint by the upper edge of each sheet. This ensures the hardware match at the top edges of the sheets, the more critical level for the meeting by superimposing.

>HYDRAULIC KESEAU DE COhMUDE UE LA CAISSE BASCULAEIE

Figure 16 shows schematically the network controlled 4-11 the hydraulic cylinders 4-and lla operating the female male matrices ef-, the cylinder 301 operating the swing-frame, the jacks 575a and 575b that provide lifting, and the descent of the mobile framework which carry the suspension structure of the bar gripper holding the cylinder and 849 maneuvering the lifting table to scissoring motion, and that the engine controller 616 which operates the lifting groups which are-hung ends, bar clamps of the door.

A main supply conduit 183 energizes the jacks in pressurized hydraulic fluid. The ends of the cylinder 411 operating the female die are connected by passageways 870 and 871 872 to a solenoid valve, type "central locking" i.e. drawer held at rest in a middle position, operated by solenoids 873 and 874. When the two solenoids 873 and 874 are désexcitésle valve spool is maintained in the middle position, preventing fluid flow and maintains the ram in the state which existed previously.

872 Entries in the valve are connected to the pressure conduit 183 and feedback conduit 193.

4lla The ends of the operating cylinder of the male die are connected by passageways and 875 876 877 to a solenoid valve type directional "central locking", operated by solenoids and 878 879_AOE280A2AO> Entries in the valve 877 are connected to the conduits and return pressure 183 193"

The ends of the cylinder of the oscillating frame 301 are connected by passageways 880 and 881 to the outputs a further solenoid 882 directional "central-locking", operated by solenoids and 884 883 and connected to pressure and return 193 183"

Solenoid valve directional Another 887, "central-locking" operated by solenoids and 888 889, has a channel d * input connected to the pressure conduit 183, an outlet pipe connected to the return line 193 and a conduit 890 connected to the top of the vertical cylinder of the group of lifting 575a located to the left in the drawing and indicated at 575 12A ' has on Figure 16. The lower end of the. cylinder 575a is connected by a conduit to a solenoid valve 891 892 compensating slide, operated by solenoids 893 and 894 and which has a pressure line 895 connected to the pressure conduit 183 and an outlet conduit 896 connected to the return conduit 193.

The top of the right cylinder, indicated in 575b, of the lifting mechanism is connected by a conduit 897 to an input of the valve 892, which serially connect the conduits -897 891 and, under certain conditions is will describe, to provide for the lowering joint the two ends of the bar gripper holding. 575b The lower end of the cylinder is connected by a conduit to the valve 898 887 _AOE280A2AO>

849 ~ The ends of the cylinder of the lifting table are respectively connected by passageways and 899' 900 to another identical slide valve 901, operated by solenoids 902 and 903, also connected to the pressure conduit 183 and feedback conduit 193-

The hoisting motor 616 (figure 12A) is connected to the conduit 183 vsous pressure and feedback conduit 193 by a gate valve 904 directional " operated by solenoids 905 and 906. The valve has a line for pressure outlet^907 for driving motor 616 due in the direction of descent of the gripper holding bar. The other outlet of the valve is connected by a line 904 908 cSté to the other of the hoisting motor 616 which it drives, when under pressure, in the direction of rise of the gripper holding bar. The speed of the motor is controlled by a branch circuit connecting the valve 904 to the return line 193 and having a valve adjustment 909-operated lever, connected in parallel with ' e a bypass valve. 910 for moderate regulate the rate of advance caused by the motor.

The 909 of the valve in position for setting the speed of the motor 616 is provided pneumatically in a manner to be exposed to about, 1a figure 17"

Figure 17 shows schematically the pneumatic network control of the raft container. - --

The upper and lower ends of the two cylinders 664 (Figure 12), which sink the pusher rods 662 to open the clamps, are connected in parallel to a solenoid valve having a spool 911' inlet connected by a conduit 912 to a pressurized air line 913_AOE280A2AO>

The valve 911 is operated by solenoids and 914 915-When compressed air arrives in the tops of the two cylinders 664, the pusher rods 662 depress and open the jaws of the clamps, mutually, when compressed air is supplied to the bases of the cylinders, the rods- pourroirs are no longer biased downwardly and the jaws close.

Figure 17 also shows the pneumatic network control of the brake disc 591 590 associated with the drum lifting (Figure 30). Pneumatic -592 The controlled arms which clamp the brake disc 591 are connected by a conduit to an air reservoir 916 917,918 supplied through a regulator from high pressure and low pressure circuits mounted-in parallel and whose inputs are connected to the pressure conduit 913-

The high-pressure circuit, -, for clamping the brake and to hold the cables' lifting wound Until the sheet gripped is to drop from between the dies bending, 919 includes a pressure regulator and a spool valve operated by a solenoid 920 921 which the energization actuates the brake..

The low-pressure circuit is similar, with a regulator low pressure and a spool valve 922 923 924 operated. by a solenoid, energized to a low pressure state, and a solenoid 925, excited to a state of zero pressure 1' exposed. The low-pressure circuit is for "seizing" of the retractor mechanism during descent of a bent glass sheet.

909 The hydraulic valve (Figure 16) for adjusting the speed of the hoisting motor 616 is operated by a lever 926 having three positions, indicated in A, and 0 B in Figure 17, each of which corresponds to an adjustment speed of the engine, under the control of a double-acting assembly comprising two rams 927 and 928 connected end-to-end and sliding piece in-a fixed race 929_AOE280A2AO>

The actuator 927 930 includes a piston mounted on a piston rod 931 whose outer end carries a domed head 932 acting on the lever 926 control valve speed -909

The actuator 928 933 has a piston mounted on a piston rod 934 whose outer end is secured to a fixed support 935 *

The inner and outer ends of the cylinder 927 are respectively connected through control valves 936 and 937 939 to a spool valve, operated by a single solenoid 940 and connected to the compressed-air line 913L ' 940 excitation of the solenoid places the pneumatic network in the desired condition to determine a first engine speed. The inner and outer ends of the cylinder 928 are connected similarly, by control valves 941 and 942, to another spool valve 943, operated by a single solenoid 944 943 * The valve is also connected to the pressure conduit 913 and 1' excitation its solenoid 944 fixed a second adjustment speed of the hoisting motor 616, as exposed.

At the end of a bending operation, the backing compLètement matrices, the raft container assumes its inclined position for receiving the hot glass sheet following, the descent of the sheet s'¹ r122 is initiated and the contacts of the relay and R123 down R12 (Figure 20) join. XI is established a circuit comprising a solenoid erases the carriage stop 242 and exits at accelerated speed the carriage of the raft container.

All rollers 8 and 13 of the furnace and the box are then driven to the moderate speed and, simultaneously, the occurrence of contact separation for triggering the shift driving the rollers of the output conveyor, which is then stop, so that the carriage comes to lie on the outlet section of the carrier ' and that may be removed and returning to the inlet end for the recharge. The then acts on a push-button re-setting to initiate the cycle " processing of the next sheet.

In the initial state of the apparatus, the two dies, male and female, are retracted, the gripper holding bar is in the upper position and the raft container inclined, for example 5 °, on 1' horizontal.

The actuator 441a for manoeuvring the male die (Figure 16) has the recoil of the matrix due to the excitation of the of the valve 877 878 solénoxde (Figures 16 and 18), provided through the contacts of a relay normally joined R73 male die R?, also including holding contacts R71 and R72 normally open contacts connected in series with the solenoid of the valve 877 879 * The solénoxde 878 excited normally maintains the male die in a stand-by position.

Also, the cylinder 411 operating the female die is operated by the relay female die H8, is holding R81, R82 normally open contacts connected in series with the solénoxde 874 872 of the valve and normally closed contacts R83 mounted in series with the winding of the valve 875 872. The solénoxde 873, normally excited, maintains the female die in a stand-by position.

The raft container containing arrays pivots under 1' action of a relay R9 vertical orientation of the rollers, is holding R91, R93 joined contacts normally mounted in series with the solénoxde 883 of the cylinder 301 and R92 normally separated contacts connected in series with the solenoid of the valve 882 884. 883 The solenoid is normally energized, so that the cylinder 301 holds the oscillating frame inclined.

Relaying of gripper holding bar E10 is connected in series with the contactor S16 high lifting position (Figure 12), the contactor of vertical orientation of the rollers S8. and the limit switch of advance of the female die SIO. E10 The relay has contacts holding E101 E102 and normally closed contacts, connected in series with the solenoid of the valve 889 887 (Figure 16). 889 The solenoid is mounted in parallel with the solenoid of the compensating valve 892 895, itself mounted in series with the two contactors lifting position high S16, respectively associated with the n groups of. right and left lift (figure 12A and 120).

E10 The relay also includes normally separated contacts E103, mounted in series to the solenoid of the valve 888 887" the solenoid 888 is mounted in parallel with the solenoid of the compensating valve 894 893, which are in turn arranged in series with two contactors lifting position low S17, connected in parallel.

In the middle of the upstroke of the bar 23, the winding 889 is energized and the hydraulic circuits of the two cylinders 575 are connected in series, fluid under pressure fed through a duct 898 887 of the valve in the low side 575b of the cylinder. The pressurized fluid exiting the top of the power cylinder passes through the conduit 897 575b, through the compensating valve 893, in the conduit 891 connected to the low side of the cylinder 575a.

Plungers of the cylinders 575a and 575b a large number of, but may not simultaneously reach stroke ends thereof high. Contactors Oelui lifting position high S16 which closes the first energizing the solenoid of the compensating valve 892 893, that changes state to directly deliver fluid under pressure in the low side of the cylinder 575a, so that the coming high lifting positions frameworks coincide as closely as possible.

During descent of the bar 23, the relay B10 of this rod is excited, separating its contacts E102 and between its contacts B103, which excites the winding 888. 892 The compensating valve is in the desired position for connecting in series the two jacks 575 * Uu fluid under pressure is supplied to the conduit 895 in the high side véi -in 575a from the side and bottom of the cylinder, through the conduit 891 and 892 through the valve, in the high side 575b cylinder. When one of the pistons reaches its bottom limit of travel, one of the switches low lifting position closes to S17 894afin energisation of the solenoid that the compensating valve 892 changes state and that pressure fluid passes through the flue in the conduit 897 895 serving the high side 575b cylinder, and the two pistons lowered together horizontally to cause the bar 23 above the matrices Glass joined.

The timer male die, previously initiated pendans residence of the sheet in the-furnace, primer controlling the male die and, after a time delay, joins the contacts T3 (Figure 18), connected in series with the contactor S9 partial recoil of the female die and with the winding of the relay E7 male die, holding E71 the terminals of which are connected in parallel with the contactor T31_AOE280A2AO> E7 When the relay energizes, the contacts separate and B73 the contacts. B? 2 meet, so that the solenoid of the valve 878 8? 7 (Figure 16) is de-energized and the solenoid excited 879 and that fluid under pressure is supplied to the conduit 876 4-11 in the cylinder to cause advancement of the male die-

At the end of the feed stroke of the male die, the limit switch matrix of travel, S14-, closes, During advance of the male die, a carriage 12 carrying a sheet of glass 9 is still moving and acts on the switch S4avant of settle against the carriage stop 24-2. The control of the contactor S4amorcejl' advance of the ^ female die, so that the lifting pins mounted on the base 1 of donor female lift the hot glass sheet 9 of the carriage 12 before it stops against the carriage stop, so that the shock experienced by the carriage with the carriage stop is not transmit to the hot glass sheet.

The male die is advanced and the contactor S4 - ' closed, when the carriage 12 is approaching the. carriage stop 24-2, the relay ^ female die E8 is energized through a contactor re-setting S15, closed, mechanism mounted on the lifting pins.

At this point, the male die has advanced into position for bending and the contactor 814de end feeding-the male die is closed, so that, the contactor 84se quahd closes during insertion of the carriage in the raft container, the female die E8 relay is energized and held in that condition by holding its contacts E81. Joined B83 The contacts normally separate and the contacts normally separated E82 meet, so that the solenoid 8? 4 of the valve 872 for manoeuvring the female die (Figure 16) is excited and 875 the solenoid de-energized, thereby starting the feed of the female die. R84 The contacts relay female die meet and E8 also trigger the timer T4 which, at Lout a delay, the contacts 141 joins solenoid driving 503a of the valve 503 (Figure 11) for applying to the male die a suction which helps to provide the bending by pulling the hot glass sheet against the surface 480 of the male die.

The contacts T41 meet for applying suction at a time when the bending is about to be finished and wherein the female die just reaches an end of its forward stroke. Later, after bending and during recoil of the female die, whereas the upper edge of the sheet is already gripped by the grippers, the contacts Ï41 se-separate and the contacts 142 of the timer T4 meet to excite the solenoid 501a of the pneumatic valve 501 to send to the male die compressed air that contributes to detach the bent glass sheet of its surface.

During advance of the female die, the lifting pins pick the hot glass sheet on the carriage and the die sections female engage against the sheet by advancing between the rollers 8 of the raft container. Then They push the glass sheet supported on the rollers 8 to the male die, The contactor SU, . indicating the partial avanee the female die, is then closed; it is connected in series with the contactor S12, normally closed, end of the female die and with the winding of the relay E9 of verticality of the rollers, which is excited and the terminals of which R91 holding meet for maintaining the relay energized through the contactor S13, normally closed, partial recoil of the male die, the switch contacts which are normally joined R93^is separate and the contacts normally separated R92 meet, so that the solenoid of the valve 882 883 (Figure 16) is de-energized and the solenoid excited and 884 that the cylinder 301 operates to return the oscillating frame to the horizontal, which causes the rollers 8 to the vertical of the raft container. It is during this tilting movement of the body that the female die reaches the end of forward stroke to complete the bending of the glass sheet, maintained on the lifting pins joined between the dies.

-When the female die ultimately reaches forward stroke, its feed limit switch S10 closes (Figure 19). SIO The contactor is connected in series with the contactor S8 vertiealité of rollers, the contactors S16 lifting position binder, which close when the lifting frames 581 are in upper positions, and with the winding of the relay gripper holding bar E10. The contactor SIO end of advance of the female die and the, S8, verticality of rollers, are connected in parallel with the contacts of the relay holding B101 E10, and the switch contacts which are normally joined Bill of a relay lifting position high Eli (Figure 20) are connected in parallel with the contactors S16 high lifting position. The contactor LES When end of advance of the female die closes E1G and that the relay is energized, contacts separate and E102 contacts B103 meet, the valves 887 and 892 (Figure 16) send of pressurized fluid to cylinders and 575a and 575b scaffolds lifting 581 (Figure 12) begin to descend to initiate the descent of the gripper holding bar 23 to the upper edge of the bent glass sheet held between the dies.

While the bar 25 is in the high position, contacts S211 and S212 of the contactor S21 top position of the bar 23 and meet the solenoid 9l4 -. of the slide valve pneumatic 911 (Figure 17) is energized to send compressed air in the tops of the cylinders sides 664et 662 (Figure 12) for pressing the piston rods and open the. jaws. During descent of the bar 23, the open jaws exactly overlap the upper edge of the glass sheet held between the matrices Glass, the jaws having penetrated up and down in the slots of the upper edge of the male die and between sections of the female die.

Once the bar 23 lowered, S221 and S222 the contacts of a contactor S22 meet and the solenoid of the valve 915 911, excited, printed to the valve a change of state as the pusher rods 662 retract and that the jaws close, under the effect of the flyweights clamps, on the upper edge of the glass sheet.

Once the push rods 662 retracted, both switches S19 close to initiate a timer T5, adjusted to introduce a delay shortest possible, not more than 5 seconds, to allow the fingers of the clips grip the upper edge of the glass sheet so that it remains well suspended from the clips when the matrices separate.

The contacts L51 of the timer T5 then meet to excite the solenoid 952 pneumatic valve 950" acting reducing the lifting pins. The pallet 556 acts on the contaeteur S15 to separate contacts normally re joined the relay s and female die B8 is de-energized. The contacts R82 and R83 separate the contacts meet, the solenoid valve 874 872 873 the solenoid is de-energized and excited, and recoil of the female die begins. The time during which the dies remain joined for bending the glass sheet can be, for example, of 8 seconds.

During recoil of the female die, the partial recoil contaeteur 89 of the female die opens, deenergizing the relay R7 male die so that the contacts B72 separate and that the contacts R73 meet, that the solenoid of the valve is excited 878 and 879 the solenoid de-energized, the male die beginning to move rearward.

At the end of the female die, its recoil end contaeteur S12 opens, the male die being recoil and recoil contaeteur S13 partial the male die opening; after opening of these two contactors, the relay R9 of verticality of the rollers' is de-energized, the contacts separate and R92 the contacts R93 meet, the solenoid 884 882 of the valve is de-energized and the solenoid excited 883, so that fluid is fed under pressure to the bottom of the cylinder 301 cêté to return the oscillating frame in an inclined position, the rollers 8 of the raft container having on the vertical inclination predetermined low, e.g. 5 °, and the furnace is ready to receive the next glass sheet. Recoil The male die continues up to an end of its stroke. The glass sheet remains freely suspended to the clamps, between the dies Glass separated, ready to descend, through the sections of extra heating and pre-cooling, in the quenching liquid.

When the oscillating frame assumes its inclined position, the contactor S7 of inclination of the rollers (Figure 47) closes. It is mounted in series with the contacts R104 joined relay RIO bar gripper holding, with the contacts of a normally joined PE1 contaeteur controlled by a photoelectric cell on which the plates 668 act as the lifting mechanism is exposed, with the contacts of the relay normally joined Rlll lift Eli, and with the coil of a relay R12 and lowering that with a timer down T6.-L ' winding of the relay R12 and the timer T6 are connected in parallel.

R122 The contacts holding relay R12 descent meet for maintaining the relay energized, the contacts R123 meet to excite a solenoid 955 which lowers the outlet stop 242 to enable the carriage 12 of the headbox output pumphandle.

The contacts 161 of " the timer down T6 immediately meet to excite the solénoxde of the valve 906 904, that controls the supply of pressurized fluid to the hoist motor 616.

Simultaneously, the contacts R124. relay meet descent R12 to excite the solenoid 94-0 939 of the valve (Figure 17) to send to the cylinder 927,937-through the valve, compressed air, which moves the piston rod 930 extended and passes the lever of the valve 932 909_AOE280A2AO> to position A, corresponding to zero speed of the hoisting motor 616, in the position B, that determines a first engine speed. At this time, the drums delevage are clamped of the brake disc, which is possible, although the engine is operating, by the clutch slip.'

After a predetermined delay, for example 2 seconds, the contacts Œ62 of the timer of descent T6 meet to excite the solenoid release brake 921 920 of the valve incorporated in the brake control circuit, to interrupt the application of the high pressure to the brake arm, and to simultaneously excite the low pressure solenoid valve 924 923 through the contacts of the relay R12 R125 down. After a period, up to 20 seconds, the contacts of the timer T6 T63 meet to excite the isolated 944de. noïde the pneumatic valve 94-3, thereby ensuring the purpose of supplying compressed air, through the control valve 94-1, the inner side of cylinder 928, which moves the latter in its cage 929 to the right in Figure 17, and tensions the lever danssa C position, determining a second speed, higher, of travel of the hoisting motor 616.

616 This passage of the engine at a second speed takes place at the desired time, when the bushing is to be accelerated by a portion of the glass sheet of the extra heating section of to establish a temperature gradient in the sheet, as described about Figure 14. The acceleration occurs, for example, when the lower edge of the glass sheet reaches the bottom of the panels in extra Heating of. j

the plates. 668 of the bar gripper holding 23 then intercept light beams projected into photocells not shown, connected to such assemblies which separate the contacts PEl switches to de-energise the relay down B12 and the timer down 16, thereby separating the contacts and T63 B124 immediately to deenergize the solénoxdes and 944 940 to ' retract the twin cylinders 927,928 and for return of the valve lever 932 909 position A, thereby bringing the lifting motor to zero speed.

At after a time delay for deceleration of the lifting mechanism, the contacts T62 separate and the solenoid brake desaerrement 921 is de-energized, thereby providing in the brake circuit re-application of the high pressure, to the brake arm to brake the hoisting motor when the lower edge of the sheet of glass reaches just the pads 80? (figure 15), in which it is supported, the contacts 161 separate after a point in time to de-energise the solenoid down 906, the motor 616 is then at rest.

While the sheet is heated in the furnace before entering the raft container for êtrebombée, closing of a push-button contactor 824 energizing the solenoid 902 (Figure 16) of the valve 901 operating the lifting table through contacts normally joined S201; to power the low side of the cylinder to give 849 the platform 30 carrying the quench vessel 26 its high position for receiving the hot shaped sheet. The vessel 26 When achieved by high position, the contacts separate and S201 the valve 901 holds the pressure ram to drive the trough 26 retains its high position.

Qualque -s seconds after stopping of the hoisting motor 616 and immersing the sheet in the vessel 26, depressing a push-button contactor S25 energizes the. solenoid of valve 901 903 lq, through the contacts joined S202, thereby ensuring the supply of fluid under pressure in the high side of the jack 849 to reduce lifting table, the tempered glass sheet remaining in 826 engaged in the gantry 807,808 when the quench vessel 26 falls. The contacts 202 separate when the tub achieved by low position, which deenergizes the solenoid 903.

The sheet is supported in the trestle 8O7,808 and is further gripped by the grippers. To open thereof, acts on an opening contactor clips S26 to excite a solenoid 957_s thereby carry pushers not shown, mounted in the pit, against the vanes of the arms 655 654afin of pull on the cables 661 and open all the clamps. The glass sheet is then deposited on the trestle, the fingers of the clips being immediately above the upper edge of the sheet, so that the clamps can. close before being lifted through the lifting mechanism.

Depressing a further pushbutton S27 then energizes, through the contacts of the relay bar joined E105 gripper holding H10, the relay lift Eli and the timer 17 lift.

The relay Eli is held; excited by its contacts holding E113 and the timer 17 instantaneously joins its contacts 171 to excite the solenoid 904 905 of the valve and the solenoid of the bypass valve 95s 910 of the circuit supplying the lifting motor.

Simultaneously, the contacts of the relay R114 lift Eli meet to excite a solenoid 959 which lifts the carriage stop 242. The contacts E116 R115 and meet to excite, through the contacts normally joined 173 of the timer 17, the solenoids speed control, and 940 944, so that the lever goes off and 932 C that the lifting motor 616 takes the maximum speed, determined by the overall rate at which the fluid passes through the valve 909, fully open, and the bypass valve 910, open, connected in parallel with the valve 909.

Therefore, the bar 23 rises quickly, before the glass sheet next penetrates between the dies and, when it is near its top limit of travel, the contacts 173 of the timer 17 lift separate, deenergizing the solenoids speed setting and 944 940. The motor 616 returns to a moderate rate, determined by the bypass valve 910, at which it is continued lifting of the bar 23.

The timer lift 17 has other contacts 172, which merge in the after a time delay to excite the solenoid release of the brake, 921, thereby interrupting the valve 920 by the application of high pressure to the brake arm and simultaneously energizes, through the contacts R127 joined, the solenoid ά ℮ zero pressure 925 the brake circuit. The brake of the hoisting motor 616 is, at this stage, fully loosened.

The contacts normally joined El 11 of the relay lift Eli separate when the relay energizes and, when the contactors lifting position high S16 are both opened, the relay bar gripper holding K10 is de-energized, its contacts E1Q2 meet and its contacts E103 d. e separate to walk up the lifting frames 581 by acting on the valves 887 and 892 to lift the. pistons in the cylinders 575 *. The contacts R105 is also separate, deenergizing the relay and the timer T7 Eli lift. After a predicted time to enable the motor 616 absorb the looseness of the cables and possible to have the certainty that the cables are raised well together and a force by the clutch to slip each drum is just sufficient to confirm the joint rise, the contacts T71 separate to de-energize the solenoids valves 905 and 958 of the circuit serving the motor, so that the lifting motor 616.s' stops. Simultaneously, the contacts T72 separate to re-apply the full pressure to the clamping arm of the brake.

Once the bar 23 fully wound, the contacts S211 and S212 meet to excite the solenoid 914et open the tweezers.

Then begins the new bending cycle and quenching of the next sheet.

Year height may be established in the sheet a substantially linear temperature gradient between the leading edge and the bo-rd rear, lower temperature, by applying a constant acceleration to the sheet as it descends between the additional heating devices 27. The distance between the bases of the panels of heating elements 27 of the vertices of the blowing boxes 28 is at least equal to the height of the glass sheets being processed, so that each glass sheet can take a constant speed before blowing scroll between the bins.

Compensates can ^? optionally the heat loss experienced in this space by providing therein a secondary heating zone cioyenne maintained at the temperature of the glass sheet leaving the additional heating devices-

Sets of operating conditions according to. the embodiment are exemplified in tables XIII, XIV, XV and XVI.

In each of these examples, of glass sheets of 60 cm high descend between sets of extra Heating d * 27 of high -90 cm

Table XIII See page: 60

In each of these examples, the upper edge of the glass sheet leaves the heating elements 27 of extra at a rate of 30 cm/s. When the lower edge of the sheet penetrates between the vertices Heating of extra panels at a rate of 2.5 cm/s, the constant acceleration of the sheet is 3.08 cm/s/s. When said penetrating velocity is 10.2 cm/s, the constant acceleration is 2.77 cm/s/s. When the penetrating velocity is 20, Acm/s, the constant acceleration is 1.73 cm/s/s.

When the heating temperature is high, for example 1600 °C, it is preferable that the glass sheet is advanced at a high speed between the panels of extra Heating. Examples of operating conditions are given in the table XIV.

See page table XIV: 61

When the penetrating velocity is 30.5 cm/s, the constant acceleration is 9.3 cm/s/s and when the penetrating velocity is 46 cm/s, this acceleration is of 5" 3 cm/s/s.

XV In table indicates the results obtained with glass sheets of 3 mm thickness and 61 cm high.

Table XV See page: 62

To obtain the output speed of. 30 cm/s from the input speed indicated, the accelerations is printed, travelling aunts i-following-_

TABLE XIII

Glass thickness: 2 mm

TABLE XIV

The. glass thickness: 2 mm

Speed of the glass sheet when crossing by its upper edge

for heating devices¹ extra: 61 cm/s

TABLE XV

Glass thickness: 3® naked

Speed of the glass sheet when crossing by sonsupérieur

heating of extra devices s 30.5 cm/s

Is obtained, with glass sheets of 4 mm thickness and 60 cm high, results similar indicated in the table XVI

Table XVI See page: 64

Accelerations constant-printed the glass sheets are stated above about the table XV.

Can be linear temperature gradient in the glass sheet by lowering the moving hot sheet d¹ a constant acceleration between panels of extra Heating of shorter than the height of the glass sheet.

The table below indicates Examples, ensemblés of operating conditions of the glasses of different thickness.

XVII See table pages: 65 and 66

The constant accelerations imparted to the films are also those indicated about the table XV.

TABLE XVI

Glass thickness: 4 mm

TABLE XVII

Height of the glass sheet s 61 cm

Height Heating of extra panels: 30.5 cm

Speed of the sheet during the crossing by its edge

head additional heating devices: 30.5 cm/s

TABLE XVII (result)

head additional heating devices: 30.5 cm/s