DEVICE FOR THE DISTANCE OF CAPS OF BOTTLES

The invention relates to an apparatus and a method for detaching and extracting extensible plastic elastomer film seals, which adhere against the edges of the openings of bottles or other containers according to the preamble of claim 1.

As is known, the sterilization of glass containers such as bottles 17 or jars 10, etc. has always required costly and usually inefficient washing operations prior to filling.

All bottles 17 designed to be filled with various liquids, as well as other glass containers 10, also designed to be filled with other sterile products are maintained in sterile conditions from the manufacturing step to the filling step, by the application of seals 2, i. e. membranes or films made of an extensible plastic elastomer, thanks to state-of-the-art techniques, which form the subject of Swiss patent applications No. 1995 0235/95 and of the associated application PCT/EP 96/00342 and other associated international applications and 1997 01/97 CH and the associated application PCT WO 98/32 668, which membranes or films strongly adhere against the openings 3 of the containers 10 or the bottles 17, thereby maintaining the content thereof in a sterile state until filling.

In order to remove these seals 2, before filling and final closure, said seals 2 have to be extracted rapidly, cost-effectively and without leaving residues on the opening 3.

Some apparatuses have been conceived for this purpose, which essentially involve a mechanical removal effect by rotating brushes, continuously assisted by air intake on the opening to be sealed, but such apparatuses, though effective, cause operation problems at high processing rates and serious difficulties in sterile operations.

These drawbacks are comprehensively solved by the apparatus of this invention, which uses a possibly sterilized compressed air jet, appropriately passing on the edge 3bis of the opening 3 of the bottle 17 or container 10, and thereby causing the aerodynamic constriction 9 of its stream. This effect is also specially enhanced by the provision of suitable, well positioned convex surfaces 16, which cause such a local pressure drop on the exposed surface of the seals 2, that said seals 2 are removed without being broken.

The invention overcomes the drawbacks of the current devices with an apparatus for detaching and extracting extensible plastic elastomer film seals, which adhere against the edges of the openings of bottles or other containers according to the preamble of claim 1, further comprising the features of the characterising part of claim 1.

The invention further comprises a method according to claim 33.

The method that uses compressed air to remove stoppers other than seals 2 made of an extensible elastomer film has already been used but in a totally different manner. A device of this kind is disclosed in document DE 40 18 113.

Here the compressed fluid coming from a traditional gun or similar tool was used in such a manner that its violent jet could detach the plug, which had a certain thickness and could oppose a resistance to the shock, and only incidentally and anyway unintentionally was assisted by the negative pressure generated by the impact of a portion of the jet against the obstacle formed by the edge of the bottle opening. In fact, bottles were unsealed by pressure and its direct consequences more than by by depression or aerodynamic vacuum.

In the case of the seal 2 made of a very thin (i. e. a few micron) extensible plastic elastomer film, which strongly adheres against the edge 3bis of the opening 3 of the bottle 17 or general container 10, the pressure and impact of the jet 8 are ineffective because they do not hit an obstacle but as in the case of the present invention an appropriately diverted incidence of the jet 8 may generate the negative pressure required to detach the seal 2. This aerodynamic action occurs due to the deviation of the jet 8 by the rounded edge 3bis of the opening 3, which deviation is appropriately enhanced by using the solid element with a convex surface 12, which adequately constricts the stream of the jet 8 on the upper surface of the seal 2.

Hence, the compressed air used to detach the seal 2 drags the detached polymer scrap 15 and conveys it to the collection station through an optional conduit 13.

In order to collect and compact the scraps 15 so that they do not pollute the environment, a few arrangements have been provided which advantageously supplement the apparatus.

Claim 8 discloses the use of a cylindrical coneshaped cyclone in which air coming out from the nozzle 1, after passing through the conduit 13 as claimed claim 7 is deviated tangentially to the inner surface at the upper cone-or cylinder-shaped cyclone body 19.

Then, the separated scraps 15 are collected in the conventional trap 38, whereas the exhausted air is vented from the upper portion of the cyclone, through a suitable ducted and centered hole 28.

Claim 11 provides the use of a metering screw 18 for conveying scraps 15 into the trap 38 of the cyclone or directly coming from the discharge 14 of the pipe 13.

This adequately sized metering screw may also have the functions of a compactor, of its size and the shape of its exhaust port (30) are adapted therefor.

Claim 12 discloses the use of a piston compactor, which is fed through an adequately sized hole 36 placed at the bottom dead center of the piston 21, by the conduit 13 or the cyclone trap 38. Once the cylinder 22 is full, the piston is operated and the scraps 15 will be compressed against the bottom wall. The cake of compressed scrap 15 will be discharged by means of a full section slide valve 23 which forms the bottom of the cylinder 22.

Typically, the inventive apparatus is used in mass bottling or filling plants.

Therefore, it will operate at the bottling or filling rate, i. e. it will have to remove as many seals 2 as there are bottles 17 or containers 10 to be filled.

To this end, the apparatus has an adequately oriented or tilting support 4, which allows the operation thereof in the most appropriate conditions as the bottles 17 or containers 10 quickly pass through it.

The edges 3bis of the openings 3 will pass before the orifice 11 of the nozzle 1 and possibly under the convex surface 16 as claimed in claim 2 and before the conduit 13 as claimed in claim 7, if the latter are present. Hence, they can be easily cleared of the seals 2 at the desired rate.

In order not to dissipate compressed air by keeping the nozzle 1 open and to increase the istantaneous pressure, a valve 5 has been provided which only opens the passage of compressed air when the edges 3bis of the openings 3 pass before the opening 11 of the nozzle 1.

This valve may have an alternate opening and closing operation, but will be more effective if it is of the rotary type, i.e. a valve essentially composed of a spool 33, controlled by a shaft that rotates in a hollow cylinder 34 having two opposite apertures.

The spool 33 will be perforated along one diameter thereof in such a manner that its two openings 35bis may coincide with those 35 of the hollow cylinder which houses it. By this arrangement, compressed air will be allowed to pass every half-turn.

This valve 5 will be driven by a suitable motor 16 of any appropriate type, whereas the valve having an alternate closing and opening operation, if present, may be controlled electrically, hydraulically, or pneumatically.

By appropriately timing the revolutions of the spool or the opening and closing operations with the feed of bottles 17 or containers 10, a proper mass operation will be possible.

To this end, a controlled feed-back system, operating with optical, electric or piezoelectric signals, will control timing.

As a supplement to the apparatus, claim 5 discloses a sterilizer.

Compressed air coming from a compressor is never sterile. In fact, the waste collected in the air tank and the pipes may be conveyed to the nozzle 1. Further, germs may be present in intake air and be ejected with air from the nozzle 1 on the opening 3 of the bottle 17 or container 10, to further grow in the content thereof.

In order to avoid this serious drawback, which would affect the advantages of extensible plastic elastomer film sealing, the apparatus has been equipped with a sterilizer, e. g. a UV sterilizer. The latter includes a pressure tank 24 with air passing through it to feed the nozzle 1. If this tank has an adequate volume, the flow may be locally slowed down, hence compressed air may remain for a sufficient time in said tank 24.

This container is provided with externally powered UV bulbs 25 having tight connections for sterilizing air in transit.

By appropriately sizing the container 24 as a function of the average outflow rate and of the radiant power of UV bulbs 25, a proper exposure for the required sterility may be ensured. Said container may also be used as a condenser for the suspended lubricant particles of the compressor system. To this end, a SAS discharge 32 will be placed on the bottom of the container 24.

Figs. 10 to 12 are different views of one embodiment that is not part of the invention, as the embodiment shown in figures 1 and 2 that is not part of the present invention.

According to a first characteristic, the scrap conveying conduit has an orifice in the form of a spherical sector-shaped cap 113 which has two recesses 213 on the opposite sides parallel to the direction of compressed air jets.

The two recesses allow the opening of the container to reach a position which coincides with the introduction of the pipe 13 under the cap 113. One, two or more blowing nozzles 11 are disposed on the sides of the container opening and are oriented in such a manner as to direct an air jet against the edge of the container opening between the cap 113 and said opening.

Particularly, in the illustrated figures, the two blowing nozzles 11 are arranged in diametrically opposite positions and perpendicular or substantially perpendicular to the container feed direction, as well as to the diametrically opposite recesses 213 of the cap 113.

A presence detector 40 detects the presence of a container and starts the nozzles for removing its plastic film seal.

Nozzles 11 are fed by pipes 6. Pressurized air is generated by a compressor (not shown) by means of a plenum chamber 41.

In accordance with an improvement, compressed air may be also heated and/or dried. In such heated and/or dried condition, the removing and conveying action is generally more effective.

As an additional improvement which increases the

Venturi effect whereby scraps are conveyed in the pipe 13, compressed air is additionally provided downstream from the inlet of said conduit 13. Said compressed air may be supplied through a pipe 6'from the same compressed air feed source to the nozzles 11. This additional compressed air supply in the conduit 13 increases the Venturi effect for scrap suction and conveyance. Furthermore, as is shown in the drawing, the additional compressed air jet directly supplied6' in the conduit 13 is synchronized with nozzle operation, thanks to the valve on the outlet of the plenum 41, which is schematically shown and generally denoted as 42.

Moreover, the plenum must be imperatively placed in the proximity of the nozzle to obtain a stronger air jet and generate a shock wave which facilitates seal detachment.

Regarding film detachment arrangements, there may be also provided ultrasound systems, sound or electromagnetic wave systems, eddy current systems, or capacitive systems, which help to weaken the seal grip.

This action may be also prepared by providing a previous thermal shock on the seal, either by freezing or heating it, or by directing an air flow thereon to change the charge characteristics of the dielectric.

More particularly, the conduit 13 has an inverted U-shaped curved end. A branch 313 is connected to the rest of the conduit 13 for scrap removal, whereas the other portion 413 ends with the cap 113.

Therefore, the conduit 13 is generally profiled in such a manner as to form a curve or a loop for connecting its inlet end to the rest of the conduit 13.

The additional compressed air jet is supplied at said curve or loop, particularly at the center of said curve or loop and, if the latter has a vertical orientation, like in the inverted U-shaped illustrated arrangement, at its apex or higher.

With particular reference to Fig. 12, multiple inlets, i. e. seal removal stations, may be provided for the conduit 13, arranged in succession and associated to one or more nozzles and to one or more presence detector.

Particularly, the conduit 13 branches off at its end by two starting portions each ending, at the inlet end, by a cap 113. The two starting portions413', 413" are disposed in such a manner as to be aligned, along the containers path, one behind the other, with reference to the container feed direction. By this arrangement, the plastic film seal removal procedure may be started successively twice, to obtain the absolute certitude that the seal is actually removed.

At each end portion, a presence detector may be provided for detecting scrap passage, and for operating the second extraction station whenever such detection signal is received, which second station may remain in the quiescent state when seal removal is detected in the first station.

Obviously, as shown in Fig. 12, the end portion may be shaped as described in the previous embodiments, in such a manner that each branch forms, with the conduit 13 connected thereto, an inverted U or anyway a curved portion, preferably having a vertical orientation, which may or may not have an inlet for a compressed air pipe, as shown in Figures 10 and 11.

• Fig. 1 shows a typical simplified operating apparatus. It includes the following:
  • 1 Nozzle
  • 2 Seal
  • 3 Bottle opening
  • 3bis Opening edge 3
  • 4 Support
  • 5 General valve
  • 6 Compressed air feed pipe
  • 7 Compressed air flow
  • 8 Jet
  • 9 Stream constriction
  • 11. Nozzle orifice
  • 17 Bottle
• Fig. 2 is a sectional and plan view of a general container, more specifically a jar hit by a compressed air jet. It includes the following:
  • 1 Nozzle
  • 2 Seal
  • 3 Jar opening
  • 3bis Opening edge 3
  • 8 Jet
  • 9 Stream constriction
  • 10 Container
  • 11. Nozzle orifice.
• Fig. 3 is a plan and sectional view of a general crescent-shaped nozzle, cut off through an angle a with respect to jet direction. It includes the following:
  • 1 Nozzle
  • 12. Nozzle orifice a Nozzle cutoff angle.
• Fig. 4 shows a typical apparatus to be included in a filling chain, equipped with an automatic valve, a convex surface element and a scrap conveying conduit. It includes:
  • 1 Nozzle
  • 2 Seal
  • 3 Bottle opening
  • 3bis Opening edge 3
  • 4 Support
  • 5 Valve
  • 6 Compressed air feed pipe
  • 7 Compressed air flow
  • 8 Jet
  • 9 Stream constriction
  • 11 Nozzle orifice
  • 12 Solid element with a convex surface
  • 13 Scrap conveying conduit
  • 14 Throat in the conduit 13, particularly at the distal discharge port.
  • 15 Scraps
  • 16 Convex surface
  • 17 Bottle a-a'A given section.
• Fig. 5 is a schematic view of a rotary valve. It includes the following:
  • 7 Compressed air flow
  • 33 Rotating spool
  • 34 Hollow cylinder with the spool 33 therein
  • 35 Opposite openings of the cylinder
  • 35bis Opposite openings of the spool.
• Fig. 6 shows a UV sterilizer. It includes:
  • 7 Compressed air flow
  • 24 Pressure container
  • 25 UV bulbs
  • 26 Condensate drainage system
  • 32 S. A. S.
• Fig. 7 shows a schematized cyclone, and includes:
  • 7 Compressed air flow
  • 13 Scrap conveying conduit
  • 15 Scraps
  • 19 Cyclone body
  • 27 Scrap discharge system
  • 28 Air intake
  • 38 Trap a-a'A section.
• Fig. 8 shows a scrap compacting screw. It includes:
  • 13 Scrap conveying conduit
  • 14 Conduit throat
  • 15 Scraps
  • 18 Metering screw
  • 30 Screw discharge
  • 37 Scrap inlet hole
• Fig. 9 shows a piston compactor. It includes the following:
  • 13 Scrap conveying conduit
  • 14 Conduit throat
  • 15 Scraps
  • 20 Piston rod
  • 21 Piston
  • 22 Cylinder
  • 23 Slide valve
  • 36 Scrap inlet hole
• Fig. 10 schematically shows a side elevational view of an apparatus that is not part of the invention, in the container feed direction. The figure includes:
  • 6 Air supply pipes
  • 6'The pipe for supplying compressed air to the scrap extracting conduit 13
  • 11 Nozzles
  • 13 Scrap extracting conduit
  • 113 Cap
  • 213 Recesses in the cap 113
  • 313 Straight branch of the inverted U-shaped end
  • 413 Straight branch of the inverted U-shaped end
  • 40 Container presence detector
  • 41 Compressed air plenum
  • 42 Valve
• Fig. 11 is a perspective view of the apparatus of
• Fig 11 which shows the same parts as shown in Fig. 10.
• Fig. 12 is a schematic view of a variant embodiment having two successive seal removal stations, in which the parts as shown in Figures 10 and 11 have been omitted for the sake of simplicity. This Figure includes:
  • 13 Scrap extracting conduit
  • 313 A common branch of the inverted U-shaped end portion
  • 413 The two vertical branches of the two inverted-U shaped branches connected to an additional common branch 313.
  • 113 The caps of each branch
  • 213 The recesses of said caps 113.