Patent GB-1229725-A (GB)
IPC: B65G57/00
Filed: 1969-07-11
Abstract: 1,229,725. Palletizing cans. G. W. HUME CO. 11 July, 1969 [16 July, 1968], No. 35069/69. Heading B8C. In a method of palletizing cans a continuously operating long belt conveyer 22 feeds cans, supplied by a single file conveyer 27, to an intermittently operating short belt conveyer 23 where the leading row of cans is held stationary by the clamp feet 31 of a clamp assembly 30 while the conveyer 23 is stationary and the build up of cans thereon is sufficient to form a complete pallet layer and close a switch CCSI so that the clamp assembly 30 is raised and the short conveyer 23 moves to transfer the pattern of cans to a stripper plate 24. The latter temporarily supports the cans above a pallet 51 carried by a hoist mechanism 50 until the full length of the pallet has been traversed by the front row, a semicircular locator 43 on an end wall 42 properly aligning the pattern of cans. The short conveyer 23 is then stopped as the clamp assembly 30 is lowered to clamp a fresh front row of cans for the build-up of succeeding pattern of cans the stripper plate 42 being moved transversely by two hydraulic cylinders CSP, Fig. 17, not shown, beneath the end wall 42 so that the cans drop on to the pallet 51. As the stripper plate 24 moves away from the short conveyer 23 a cam (45) thereon, Fig. 12, not shown, closes a normally open valve (46) in a vacuum line (47) to supply vacuum to suction cups 44 beneath the plate 24 and pick up a sheet of paper P from a stack on a tray 55 which has been raised at one end, in an arc, and which is subsequently lowered. After the hoist 50 has descended the height of one can the stripper plate 24, carrying the picked-up paper sheet P, is returned to its original "IN" position the cam (45) opening the valve (46) to bleed the vacuum so that the sheet is laid on top of the stacked cans ready to receive the next layer. This sequence of operations is automatically repeated, cyclically, until the last layer of cans has been deposited on the pallet 51 whereupon the stripper plate 42 is maintained in its retracted "OUT" position, a platform 60 on the hoist continuing to move downwards to deposit the loaded pallet on a pair of feedout conveyer chains 81 which are then started to move the pallet out of the machine. An empty pallet, released from the bottom of a stack in a feed bin 71 by withdrawing pairs of dogs 70 on each side of the stack, is then dropped on to a pair of chain conveyers 75 which feed it on to the conveyers 81 to engage a stop 78 which starts a motor to move the hoist 50 upwardly. The hoist 50 in its upper position, causes the stripper plate 42 to move towards the conveyer 23 to its "IN" position and deposit a sheet of paper P on the fresh pallet 51. When the loaded pallet is clear of the machine the conveyer chains 81, 75 are stopped, and the dogs 70 are again released to place another pallet on to the chain conveyer 75 and then spring back and catch the next lowermost pallet. The platform 60 of the hoist 50 is mounted on a set of screws (61-64), Fig. 3, not shown, for movement up and down by a motor (HM), Fig. 15, not shown, and carries a cam rod (68) which co-operates with a series of micro switches, Fig. 5, not shown, in an electrical control circuit which comprises a master control unit MC, Fig. 11, connected to all of the other circuits for individually controlling an hydraulic pump HP, a vacuum pump VP, the long conveyer 22 LD, the can clamp CC, the short conveyer 23 SO, the stripper plate circuit SP, the hoist circuit H, the paper tray circuit PT, the pallet conveyer circuit PC and a pallet feed circuit PF, Figs. 12-16, not shown. The stripper plate transverse movements begin slowly, become faster, and then come to a gentle stop. To facilitate setting up the machine and maintenance, the stripper plate, conveyer chains 81, and the hoist 50 are provided with manually operable jog-in-and-out switches.