Patent GB-762809-A (GB)
Title: Improvements in or relating to conveying apparatus for the line production of articles
IPC: B65G47/51
Filed: 1954-07-05
Abstract: 762,809. Conveyers. CROSS CO. July 5, 1954 [Sept. 11, 1953], No. 19675/54. Class 78 (1). In apparatus including a conveyer for transporting a succession of workpieces past a series of machines in a production line, a storage unit is arranged to receive certain of the workpieces from the line in advance of a machine, and control means for the conveyer and storage unit are interconnected in such a way that the storage unit returns workpieces to the line for delivery to the machine in the event that the conveyer fails to do so, e.g. if a preceding machine is temporarily shut down. As shown, a step-bystep conveyer is associated with each of the machines 16, 18 in a production line and with a storage unit 30, all the conveyers 'being actuated from a central control 34 so that after completion of a series of operations workpieces may be stepped forward to pass successively over each of the positions 20, 12, 24, 28, 22, 14, 26 in the line. The conveyer associated with the storage unit is formed by a bar 62 reciprocated longitudinally by a fluidpressure cylinder 60 and having two pairs of spaced dogs 68 for engaging the workpieces which are lifted at the end of each forward stroke by a cylinder 72, Fig. 3, acting on a lever 70 attached to the bar. Positions 12, 14 are the operating positions of the machines 16, 18 while position 28 is the first compartment of the storage unit 30. The latter comprises an endless articulated structure 48, Fig. 3, the links 80 of which provide platforms for separate workpieces and have projections 84 separating adjacent platforms and providing a means for controlling the step-by-step movement of the structure when receiving from or delivering to the line. For this purpose a switch LS-4 is located at the remote end of the conveyer and switches-off the drive every time a projection 84 engages its actuating lever. The drive is re-started in the appropriate direction for receiving from or delivering to the line by a control circuit including switches LS-1, LS-2, LS-3 actuated by workpieces occupying the positions 24, 28, 22 such that if spaces 24, 28 and 22 are not occupied owing to shutting down of machine 16 the storage device will feed workpieces to the line at the next control actuation, whereas if spaces 24, 28 and 22 are all occupied and machine 18 is shut down, the storage device will receive workpieces from the line. The control circuit, Fig. 6 (not shown), includes in addition to the switches LS-1, LS-2, LS-3 and LS-4 the following: a switch LS-5, Fig. 3, which is closed so long as the store is not empty, a switch LS-6, Fig. 3, which is closed when the store becomes full, switches LS-7, LS-8, Fig. 1, closed respectively at the rearward and forward limits of movement of the bar 62, switches LS-9, LS-10, Fig. 3, closed respectively at the upper and lower limits of movement of the dog-lifting lever 70, switches 36, 38, Fig. 6 (not shown), closed when the respective transfer movements of the conveyers associated with the machines 16, 18 have been completed, corresponding switches (not shown) closed at the completion of the operations of the respective machines on a workpiece, and a manual control switch (not shown) for the conveyer associated with each machine, for preventing actuation of such conveyer when the associated machine is closed down. Specification 753,916, [Group XXII], is referred to.