GB827324A - Improvements in or relating to automatic palletizers - Google Patents

Abstract

827,324. Pallet loading machines. DRAMARD, M., and KUNTZ, X. May 2, 1957, No. 14090/57. Class 94(1). Sacks to be stacked on a pallet 6, Fig. 1, are fed to trap doors 54, Fig. 2, above the pallet, and after each sack has fallen on the pallet a turntable 25 carrying it is turned through a right angle so that the sacks are laid in the configuration shown in full lines in Fig. 5. After each layer has been completed a platform 12, Fig. 1, carrying the turntable and pallet is moved through the distance a, Fig. 5, and the pallet is lowered by an elevator 11 Fig. 1, through the thickness b of a sack, so that the next layer of sacks is laid in the staggered position shown in broken lines in Fig. 5. After a predetermined number of courses have been laid on the pallet, in the construction illustrated, the elevator 11 lowers the pallet 6 to bridge a pair of transversely spaced chain conveyers 26 which carry the loaded pallet to a rollerway 28 and receive a fresh pallet from a stack in a section 3 of the machine. The bottom pallet of the stack normally rests on a pair of chain conveyers 44 while the remainder of the stack is supported by pawls 43. After the bottom pallet in the stack has been fed an elevating table 31 raises the stack so that the|pawls 43 may be retracted for re-engagement with the next-to-bottom pallet of the stack after the table has been lowered again. The sacks are fed down a slide 50 to an endless belt 51 which carries them under a calibrating roller 58 adjusted by a handle 62 to determine the thickness of the sacks. The sacks then pass down a slide 53 to the trap doors. All the motions of the machine illustrated are effected by geared electric motors. The motor 23 for reciprocating the platform 12 is carried by the platform and connected by a crank 22 to the elevator 11. The motor 24 for turning the turntable 25 is connected directly to the turntable. The elevator 11 is raised and lowered by cables passing round pulleys 16 driven from a motor 18. The table 31 operating the stack of pallets is operated through a crank from a further electric motor. The trap doors 54 are opened, against a biasing weight, by the weight of the sack when a solenoid operated brake is released. The operations of the machine may be controlled automatically by limit switches detecting the completion of each motion, feeler switches detecting the presence of sacks on the trap door 54, on the shoot 53, and on the belt 51, by a counter set to the number of layers in each stack, and by a photo-electric cell which stops the lowering motion of the elevator 11 when the top course of sacks is lowered sufficiently to clear a beam controlling the cell. Alternatively, each motion of the machine may be initiated manually and stopped automatically. A manual switch may be provided for stopping all the operations of the machine and a further switch (not shown) may stop operation of the machine if it reaches the stage at which a pallet should be fed from the storage stack while a fork-lift truck is adjacent the storage column 3 delivering further pallets to it. Ejection of pallets from the storage base 3 may also be prevented when only two pallets are left on the stack.