GB281398A - Improvements in and relating to multiple unit electric control - Google Patents

Abstract

281,398. British Thomson-Houston Co., Ltd., and Sarjeant, C. J. Sept. 3, 1926. Governors, applications of; relay or power apparatus.-Diesel engines or other prime movers in one or several coaches of a train can be controlled at any of several points of the train, each prime mover having a governor adjusted by an electric motor which is controlled by a master controller provided at each control point. The master controllers 1 are interconnected by train wires 4 to each electric controlling motor 2 which act e.g. on a pivoted lever to compress a synchronizing spring on each governor to control the prime mover. The electric motors 2 are connected in parallel, and to cause them to move through equal or corresponding distances they are provided with mechanically coupled dial switches 3 while the positions of the master controllers 1 are electrically interlocked with the corresponding positions of the dial switches. As soon as a motor has driven its dial switch to a position corresponding to that of the master controller the dial switch 3 causes the circuit of the motor to be interrupted, thus bringing the motor to rest. Each master controller has the usual dead man's handle 5, which automatically interrupts the motor circuit and applies the brakes. The master controllers 1 are also provided with segments 6 to interrupt the control circuit of the exciter fields of the generators (not shown) supplying power to the motors in the off position of the controller so that the supply is taken from the driving motors when the controller is in the off position. Double field contacts 7 on the main shaft of each controller, control the coil circuits of contactors 8 and 9, which in turn control the coil circuits of contactors 10, 11 respectively through the contacts of dial switch 3 and master controller 1. Contactors 10, 11 control the two field windings 12, 13 of motor 2, one for each direction of rotation. Limit switches 14 are provided at the ends of travel of the dial switches to prevent the motors from overrunning. Each controller 1 has an additional small two-position removable handle, removable when the main controller handle is in the off position, and the main handle can only be raised from the off position when this small handle is in the other position. When the lever compressing the governor spring reaches the position of minimum compression, the limit switch 14 opens, to interrupt the motor circuit and the contactor 16 circuit, thus giving minimum governor spring compression for starting up.