Electrical control device for controlling setting up of butterfly type safety valve in stand-by position, has Darlington PNP and NPN type power transistors to supply motor, and resistor of low value mounted parallel to motor

摘要

The device has Darlington PNP and NPN type power transistors (4, 5) to supply an electrical motor (1) in a direction, and Darlington PNP and NPN type power transistors (6, 7) to supply the motor in another direction. A resistor (22) of low value is mounted parallel to the motor. The transistors (4, 6) have base resistors (10, 11) connected on collectors of transistors (5, 7), respectively.