GB783657A - Polyphase electrical circuit breaker with trip indicator - Google Patents

Abstract

783,657. Automatic circuit-breakers. ALLIS-CHALMERS MANUFACTURING CO. Sept. 9, 1955 [Sept. 22, 1954], No. 25901/55. Class 38 (5). In a polyphase circuit-breaker arrangement, individual tripping indicators 54 are provided for each phase, the indicators being rotatably mounted on a common shaft 58 and so connected thereto as to cause rotation of the shaft when any of the indicators is moved into a position to indicate tripping. The indicators 54 are carried by sleeves 60 rotatable on the shaft but having recesses 62 in which pins 71 extending through the shaft 58 engage. When the armature 45 of a tripping electromagnet 40 is attracted, it moves a pin 67 to release a latch pin. The indicator is turned by gravity and a torsion spring 70, the associated sleeve 60 engaging the pin 71 and turning the shaft 58. The lost motion connections between the pins 71 and the sleeves 60 permit the rotation of the shaft by one indicator while the other indicators remain latched. When the shaft 58 is turned into its " tripped " position, a cam 82 secured to the shaft operates an alarm control switch 87 and an arm 81 moves into abutting engagement with a block 83 to prevent accidental reclosing of the circuit breaker without resetting of the indicator shaft 58. Resetting of the shaft and any tripped indicator is effected by depressing a button 74 which turns the shaft 58 through links 75 . . . 77. The general arrangement of the circuit - breaker contact assembly, tripping mechanism and closing mechanism is that described in Specification 775,940.