Improvements in control systems for conveyors

1,030,581. Programmed control of conveyers. JERVIS B. WEBB CO. Feb. 27, 1965, No. 8533/65. Heading G3N. An overhead conveyer comprises load-carriers 16 associated with propelling chain 14, and unloading or like mechanism 18 adapted to be actuated by an electrical signal. Signal-carriers 20 are each secured to a trolley immediately in advance of a load-carrier, a recording station 22 impressing a destination code signal upon a signalcarrier by operation of unit 24 including key board 25. An erase element 26 is adapted to remove previously stored information from a signalcarrier. A magnetic code signal in a signal-carrier is sensed at read station 28, the mechanism 18 being operated in response to the passage of a signal-carrier bearing the code for that particular station. Each signal carrier 20 has a shell non- magnetic material and is coupled to the conveyer by a hanger bracket allowing relative movement transverse to the path of conveyer movement whereby surface contact is ensured between a face of the carrier and a guide plate of the recording station. Three magnetizable memory elements A, B, C, are mounted on the carrier 20 to form a specific pattern, a signal element S comprising a permanent magnet being spaced from the pattern so as to travel on a distinct path, Figs. 2-4 (not shown). The erase element 26 comprises electro-magnets which are normally excited with A.C., but this excitation may be controlled by switch 56 to prevent erasure, Fig 5 (not shown). The recording unit 22 contains three electromagnets EM-A, EM-B, EM-C, in the same pattern as the memory elements, as well as switch S-Rn adapted to respond to the passage of element S, Figs. 2, 3 (not shown). The reading station 28 comprises detectors 70, 71, similar to the switch S-RN, positioned to correspond with the memory elements A, C, carrying north and south polarities respectively. Memory unit B is unpolarized. Detector units at other reading stations are arranged in polarity and position to detect the passages of memory units having the polarities coded for those destinations, Fig. 9 (not shown). Twelve destinations are controlled from keyboard 25 which has unit-digit keys 1, 2, 3, and ten digit keys 10, 20, 30, for the energization of electromagnets EM-A, EM-B, EM-C. Actuation of key 20, for example, energizes a self-holding relay which in turn operates a further relay preventing any other ten-digit key from effecting the circuit. Connections in a diode matrix are set up to energize two