Improvements in or relating to electric control systems embodying transistors

Abstract

Abstract 766,867. Switching systems for consumption apparatus. WESTINGHOUSE ELECTRIC INTERNATIONAL CO. March 30, 1955 [April 5, 1954], No. 9249/55. Class 38 (4). An A.C. load 413, such as a motor, or a bank of lamps or heating resistors, is switched by a symmetrical junction transistor 415 interconnecting the load and supply source 407, the transistor being either conductive or non- conductive according as to whether positive or negative bias voltage between the base electrode 421 and end electrodes 417, 419 is selected by a control switch 457. As shown, positive bias voltage is provided by rectifiers 435, 449 energized from transformer windings 439, 443, whilst negative bias voltage is obtained over oppositely rectifiers 423, 433 and associated windings 427, 429. In modified arrangements, batteries replace the transformer windings and control is by a simple " on-off " switch.

Inventors

No inventors recorded.

Bibliographic Details