GB422702A - Improvements in and relating to electrical remote control systems for motors operating between limits - Google Patents

Abstract

422,702. Control of motors. INTERNATIONAL GENERAL ELECTRIC CO., Inc., 120, Broadway, New York, U.S.A.- (Assignees of Allgemeine Elektricitõts-Ges.; 2, Friedrich Karl-Ufer, Berlin) July 11, 1933, No. 19651. Convention date, July 11, 1932. [Class 38 (iii)] Travelling between predetermined limits.-A remote control system for an electric motor operating between limits comprises control switches 1, 2, a single control circuit 5, and relays 9, 10, corresponding to each direction of the motor, the relays 9, 10, in operating, closing contacts 17 whereby they are maintained over circuits which are independent of the control circuit, but which are interrupted by limit switches 7, 8 when the motor reaches either of its limits. During operation of the motor in either direction, it may be stopped by closing a control switch 1 or 2 corresponding to reverse movement. The closure of the control switch completes a short-circuit for the coil of the operative relay over the control circuit 5, anda switch 11 driven by the motor. The consequent opening of the operative relay closes over contacts 16, and a switch 12 a circuit for the coil of the reverse relay, so that the motor reverses, and when it reaches its limit it is stopped by the opening of the reverse relay by the switch 12, which is also driven by the motor. In a modification, Fig. 2, (not shown), the motor is stopped and reversed to its limit during its movement in either direction by operation of the reverse control switch 1, or 2, which energizes the reverse relay over a switch driven by the motor. The closing of the reverse relay interrupts the maintaining circuit of the previously operated relay. The main contacts of the relays in this arrangement may be locked together or time delayed.