"APPARATUS TO MANUFACTURE REINFORCING MESH" The present invention relates to automatic machines for the continuous production of concrete reinforcing mesh particularly mesh for use in trenches or concrete beams. Conventionally steel mesh for trenches has been manufactured manually by securing longitudinal rods to spaced stirrups. Usually the rods are secured to the stirrups by tie wire. Continuous automatic machines have attempted to manufacture the reinforcing mesh, however they have not successfully provided a means of locating and securing the stirrups to the longitudinal rods.

It is the object of the present invention to overcome or substantially ameliorate the above disadavantages. DISCLOSURE OF INVENTION

There is disclosed herein an apparatus to continuously automatically manufacture concrete reinforcing mesh consisting of a plurality of spaced longitudinal rods joined by longitudinally spaced transversely extending stirrups, said apparatus comprising rod support means to engage the rods so that they are moved through the apparatus so as to retain the rods in a predetermined relationship, said relationship being that said rods are parallel and coextensive; a stirrup support means adapted to support the stirrups adjacent the rods at predetermined longitudinally spaced intervals along the rods; fixing means to secure the stirrups to the rods so that said rods are retained in said relationship; motor means to engage the rods to cause intermittent movement thereof through the apparatus; control means to co-ordinate said motor means to the stirrup supply means, and fixing means so that said stirrups are secured to said rods in between movement of the rods.

BRIEF DESCRIPTION OF DRAWINGS A preferred form of the present invention will now be described by way of example with reference to the accompanying drawings wherein:

Figure 1 schematically depicts in perspective view an apparatus to automatically continuously manufacture

concrete reinforcing mesh;

Figures 2 and 2a schematically depict in end elevation an arrangement to provide the mesh with stirrups; Figure 3 schematically depicts in perspective view a device to locate the stirrups between the longitudinally extending rods forming part of the mesh;

Figure 4 schematically depicts in perspective view a welding head to secure the stirrups to the rods;

Figure 5 schematically depicts in end elevation a welding arrangement having the welding heads of Figure 4; Figures 6a and 6b schematically depict an arrangement to draw the mesh and therefore the rods through the welding head of Figure 5;

Figures 7a and 7b schematically depict a guillotine to cut the manufactured mesh to required lengths.

Turning firstly to Figure 1, the apparatus 10 is adapted to manufacture reinforcing steel mesh 11 from a plurality of longitudinal rods 12, which are held in a spaced parallel generally coextensive relationship by stirrups 13. The apparatus 10 has several work stations, the first of which includes a plurality of spools 14, which receive coils from which the rods 12 are taken. Upon leaving the spools 14 the rods 12 pass through a second workstation 15 in which the rods are straightened and fed to a third workstation 16. Additionally at the workstation 15 the rods are arranged so as to be parallel at predetermined relative positions. At the station 16 there is provided a stack 17 of stirrups 13, which are firstly located in a horizontal position between the rods 12, whereafter the stirrup 13 is raised to a vertical position and welded to the rods 12. The next workstation 18 engages the mesh 11 so as to pull the rods 12 through the various workstations. The manufactured mesh 11 is cut to desired lengths by a guillotine 19. Turning now to Figures 2a and 2b and Figure 3, there is schematically depicted the stack 17 of stirrups 13 which are held by guide structure 20 so as to be fed under the influence of gravity to a slide 21. The slide 21 pushes

individual stirrups 13a to a horizontal position located between the two sets of rods 12a and 12b. The slide 21 is caused to reciprocate by a ram 22. Once the stirrup 13a is located between the rods 12a and 12b it is raised to a generally vertical position by means of an elevating arrangement 23 which includes a first pivoted frame 24. The frame 24 is caused to rotate about the axis 25 by means of a ram 26. The radially outer operation of the frame 24 includes two stirrup engaging fins 27 which pass between the rods 12b so as to engage the stirrup 13a and raise the stirrup 13a to a vertical position under the influence of the ram 26.

Turning now to Figures 4 and 5 which schematically depict a welding head to secure the stirrup 13a to the rods 12. The stirrup 13a, when raised to its vertical position, is located at a predetermined location by locating members 28 which are forced outwardly so as to engage within the corners of the stirrup 13a. The welding head 29 includes a plurality of conductive rods 30 which are moved into engagement with the rods 12 so as to provide an electric current thereto to be passed through the stirrup 13a to the locating members 28. The current causes fusing of the metal at the abutment of the rods 12 with the stirrup 13a to thereby weld the stirrups 13 to the rods 12. The locating members 28a are moved into engagement with the stirrup 13a by means of a rotating cam 31 which has four lugs which engage inclined surfaces 32 forming part of the locating members 28. The locating members 28 would be biased to a radially inner position relative to the cam 31 to allow the stirrup 13a to pass to the next station. The conduction rods 30 are moved into electric contact with the rods 12 by means of rams 33.

Turning now to Figures 6a and 6b wherein there is schematically depicted a mesh advancing device 34 which is adapted to cause intermittent movement of the manufactured mesh 11 so as to draw the rods 12 through the welding head 29. The device 34 firstly includes a guide frame 35 which guidably receives a movable frame 36. The movable frame 36

is provided with a plurality of guide rollers 37 which contact the guide frame 35. The movable frame 36 is caused to reciprocate from an advanced position depicted in Figure 6a to a retracted position depicted in Figure 6b by means of a ram 36. The movable frame 36 has mounted on it two abutments 39 and 40 which are adapted to selectively engage the stirrup 13. The abutments 39 and 40 have converging surfaces 41 which allow the stirrup 13 to move from a position upstream of the abutment 39 to a position whereby leftward movement of the movable frame 36 will cause leftward movement of the manufactured mesh 11. More particularly the upper abutment 39 is vertically slidably received within the movable frame 31 to thereby allow movement of the stirrup 13 to a position whereby it will be engaged by the abutments 39 and 40.

Turning now to Figures 7a and 7b there is schematically depicted a guillotine 42 which is adapted to cut the manufactured mesh to predetermined lengths. The guillotine 42 includes a frame 43 from which upwardly extend guide rods 44.

The guillotine further includes a first cutting arrangement 45 adapted to cut the rods 12b and a second cutting arrangement 46 adapted to cut the upper rods 12a. Each of the cutting arrangements 45 and 46 includes a stationary cutting blade 47 having a plurality of slots 48 within which the rods 12 are located. There is further provided a movable cutting blade 49 which has slots 50 which are selectively alignable with the slots 48. Upon the rods 12 being located within the aligned slots 48 and 50, the movable blade 49 is moved to a position whereby the slots 48 and 50 are no longer aligned, thereby severing the rods 12.

With particular reference to Figure 7b it can be seen that there is a ramp surface 51 which will cause the manufactured mesh to rise above the blades 48 and 50 so that the stirrups 13 may pass by the cutting arrangements 45 and 46. Additionally the upper cutting arrangements 46 would be provided with a ramp surface which would cause vertical moement of the upper cutting arrangement 46 to thereby allow

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the stirrups 13 to pass through the guillotine. The position of the upper guillotine 46 is defined by an adjustable threaded member 52 which is received within a threaded passage 53. The above described machine would further include a control mechanism which would co-ordinate the welding head, mesh advancement device and guillotine.

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