PRODUCTION METHOD AND MEANS FOR CONCRETE ARTICLES

PATENT SPECIFICATIOH™ "477!ImClass (52) 70,1. Int. CI. (6i) B28b.Application Number (2i) '47^ 744/72Lodged (22) 27th October, 1971.(Accompanied by Provisional Specification).Complete Specification ^ PRODUCTION METHOD AND MEANS FOR CONCRETEARTICLES-Lodged (23) 13th October, 1972. Accepted (44) 8th July, 1974. Published (4i) 20th December, 1973.Convention Priority (30)Applicant (7i) CONCRETE INDUSTRIES (MONIER) LIMITED.Actual Inventor (72) ROBERT LYNDON BRATCHELL.Related Art (66) 128,466(24,966/45)70.1; 98.4.151,075(35,895/50)70.1; 81.2.143,691(24,092/48)81.2; 70.1; 98.4.The following statement is a full description of this invention, including the best method of performing it known ^t0U8^:______________________________________________________________________________ltMO/79—1.F. 0. Atklmon, Government Printer, ConberroX623-83-3D-14P.C.SPECIFICATION 451003 Application No. 47744/72 Classification 70.1 International Classification B28b AMENDMENT (As amended under Part VIII of the Patents Act 1952-1973) In the printed specification: Page 3, line 18, delete "can, for example, be" and insert ", in being". Page 3, line 19, delete "and in this way" and insert "are unloaded as", Page 3, line 20, delete "can be unloaded". Page 4, line 5, delete "and a plurality of" and insert ",". Page 4, line 6, delete. Page 6, line 11, delete "33" and insert "(not shown)". Claim 4, line 1, after "wherein" delete "the". Claim 4, line 2, delete "comprises" and insert "comprise". Claim 5: Cancel. Renumber claims 6 to 10 as new claims 5 to 9. New claim 6, line 1 , delete "6" and insert "5". Drawing: Cancel Fig. 1, 2 and 3 and insert new Fig. 1, 2, and 3 attached herewith.

_c pjooB.K. Maddern & Associates.

SPECIFICATION 451,003 Application No. 47,744/72 Classification 70.1 International Classification B28b AMENDMENT (As amended under Part VIII of the Patents Act 1952) In the printed specification : Page 7, line 27, after "after" insert "one half an". Page 7, line 28, delete "four hours" and insert "hour .

_p100R. K. Maddern & Associates, Adelaide.

47 7 4 4"/ttThis invention relates to a method of moulding concrete ties used for retaining the rails of a railroad track. Such ties are also known as sleepers.In the production of railway ties it is desirable to produce at a fast rate, and accordingly it is usual practice to stretch out prestressing rods over a considerable length, the rods being contained in a series of aligned moulds, concrete being poured into the aoulds and allowed to set while tension is retained on the rods, tension then being released from the ends of the rods, the rods being cut between the moulds and the ties being removed from the moulds. Two difficult problems are encountered with this type of production, the first being that the prestressed rods are strained by some considerable distance if they are long, and upon release the moulds move towards one another so that it becomes difficult to arrange any mechanical unloading device, and the second problem is that railroad ties are too heavy for successful handling by operators without unloading devices, and the unloading devices proposed heretofore which have been of a conventional nature are slow in their use.With the object of providing improvements which will assist in achieving fast production rates, this invention in one of its forms comprises a method of moulding concrete ties which comprises the steps:-aligning end to end a series of moulds of shape for forming the concrete ties,positioning a series of reinforcing wires in the«451.0 0347.7 44n2moulds in parallel spaced relationship to one another, securing the ends of the reinforcing wires toanchor means at respective ends of said line of mouldsand.straining said wires,mixing portland cement, aggregate, sand and waterto form a wet mix of concrete and allowing the concreteto set and cure,transporting the wet mix of concrete over the moulds and simultaneously discharging said concrete into the moulds to thus fill the moulds and surround the reinforcing wires with concrete,severing the reinforcing wires between adjacent moulds of said series of aligned moulds, andinverting the moulds over the forks of a forklift truck, and shaking the moulds with the truck forks to achieve release of the ties from their moulds and in turn discharge respective concrete ties onto said forks.The concrete articles can, for example, be discharged onto the forks of a fork-lift truck, and in this way a group of concrete articles can be unloaded from multi-cavity moulds simultaneously. The means for inverting the moulds may comprise a tilt frame which engages but is not secured to a base so that the moulds may move along the base upon relaxing of the tension in the prestressed reinforcing members.45100347.7 4 4n2An embodiment of the invention is described hereunder in some detail with reference to and is illustrated in the accom­panying drawings, in which:-Pig. 1 is a diagrammatic, fragmentary view which shows two of a series of aligned multi-cavity moulds and a plurality of reels of reinforcing wires at one end thereof,451.0 0347,7 4 4/12Fig. 2 is a typical section through a multi-cavity mould, showing the reinforcing wires in place.Pig. 3 is a diagrammatic plan of means for securing the ends of the reinforcing wires at an end of the line of moulds, and means for straining the wires.Fig. 4 is a diagrammatic longitudinal section through a hopper which transports a wet mix of concrete over the moulds and simultaneously discharges into the moulds.Fig. 5 is a diagrammatic cross-sectional representation of means for inverting the moulds to discharge concrete ties from them.Fig. 6 is a cross-section through a multi-cavity mould, andFig. 7 is a perspective view of a tilt frame.In this embodiment four channels 10 are arranged in two pairs symmetrically with respect to a centre line designated 11 and extend longitudinally along a concrete foundation 12 (not shown in Fig. 1) , the channels 10 being spaced relative to one another and being parallel and forming two longitudinal base frames. Between the pairs of channels 10 are positioned rails 14 which support the wheels 15 of a slewing crane 16 having a hoist 17 on its jib 18 (Fig. 5). For the sake of simplicity the drawings illustrate only one side of the centre line 11, and the slewing crane is only partly illustrated.The ends of each longitudinal base frame are provided with beams for supporting the mm&n of reinforcing wires which are pretensioned as concrete is poured into moulds.5 45100347,744^One such beam is designated 22 in Fig. 3 and supports a series of abutment blocks 23 through tension links 24, the abutment blocks 23 themselves supporting loose wire retainer blocks 25. The beam 22 which is illustrated in Fig. 3 is not fixed but has secured to it a pair of rams 28, the rods 29 of which are carried by an anchor frame 30. Operation of the rams 28 will apply tension to the wires 21. The tensioning rams 28 are positioned at one end only of the series of moulds, while at the other end of the series of moulds the wires 21 are fed into the moulds 32 from reels 33, the wires also passing through loose wire retainer blocks 25 supported in like manner to that shown in Fig. 3 but at the other end the retainer blocks 25 abut a fixed beam. For the sake of simplicity this has not been illustrated in Fig. 1. The moulds 32 are freely supported on the channels 10 and have between them spacers of two types. Fig. 2 illustrates channel shaped spacers 36 (also shown in Fig. 4), together with plates 37 which flank the channel shaped spacers 36, the plates 37 being provided with vertical slots 38 which co-operate with the adjacent horizontal surfaces of adjacent spacers 36 to form rectangular openings which position the reinforcing wires 21 in a grid-like pattern as illustrated in Fig. 2. Throughout this embodiment the number of reinforcing wires per tie is shown as nine, that is, three rows of three, but normally more than nine would be used in practice, one typical pattern being three rows of six, that is, eighteen reinforcing wires per tie.451.0 0347.7 4 4/72The need for the vertical slots 38 to position the wires laterally is less than the need for the spacers 36 which position the wires vertically, and the channel shaped spacers 36 together with the plates 37 are used only once in say, every five of the series of moulds, the remaining four being separated by flat spacer plates designated 40 which are illustrated best in Fig. 4. Before the wires are positioned the moulds are sprayed with oil or some other release agent, and the channels 36 and plates 40 respectively are effective in retaining the wires away from the bases and side walls of the moulds so that the wires are not contaminated with release agent.The moulds have inserts 41 inserted therein and retained in place by a pin as shown in Fig. 2, the inserts 41 after moulding becoming the shoulders to which the rails are secured on a track.After the wires have been positioned, have had their ends secured in the retainer blocks 25, and have been strained by operation of the rams 28, a hopper 42 is charged with a wet mix of concrete comprising portland cement, aggregate, sand and water and the hopper 42 is traversed over the moulds as shown in Fig. 4 discharging the wet mix of concrete into the moulds and screeding the concrete with a screed plate 43 as it traverses. The hopper 42 is provided with a plurality of vibrators 44 arranged as shown in Fig. 4. !After the concrete has partially set (say, after four hours) the spacers 36 and 40 and the retaining pins7 ,j 451,0 0347,744/72 means for severing reinforcing wires between adjacent moulds, and means for inverting the moulds to thereby discharge respective concrete ties therefrom which comprise hinge means having a tilt frame positionable alongside each of said moulds in turn, means on the tilt frame co-operable with said mould support means to fix the tilt frame to the mould support means, a pivot bar on the tilt frame, receiving apertures in each of the moulds arranged to receive the pivot bar, and a crane arranged for the lifting of the multi-cavity mould. 9. A method of moulding concrete ties substantially as described in the specification with reference to and as illustrated in the accompanying drawings. 10. Means for moulding concrete ties substantially as described in the specification with reference to and as illustrated in the accompanying drawings. Dated this 21st day of June 1974. CONCRETE INDUSTRIES (MONIER) LIMITED, By its Patent Attorneys, R.K. MADDERN & ASSOCIATES.

1445X003477 44/72451.0 0347744/72451.0 0318M47,7 4 4/72Ffcj. 7451,0 0347,7 4 4/722047,744^Viq-?>. 4 5 1,003