GB1322557A - Motor-operated spring-closing circuit breaker - Google Patents

Abstract

1322557 Automatic circuit breakers WESTINGHOUSE ELECTRIC CORP 5 Oct 1970 [6 Nov 1969] 47251/70 Heading H1N An automatic circuit breaker has closing springs 79, Fig. 1 charged by means of a motor 101 the output shaft 133, Fig. 3, of which has a roller arm 137 driven by the shaft to actuate the charging mechanism. The three-pole circuit breaker has a housing structure 7, Fig. 1, supporting the circuit breaker 9, the housing comprising a base plate 11, side plates 13 and a pair of metal centre plates 17. The bearing support for the shaft 133, Fig. 3, is fixed in one centre plate and, as the shaft rotates, the arm 137, carrying roller 139 engages the reciproeating pawl 78 which advances the ratchet 75 and crankshaft 71, thus tensioning the spring 79. A limit switch, coinciding with a missing tooth portion of the ratchet wheel, de-energises the motor drive when the spring is fully charged. In Fig. 2, the contacts 23, 21 are shown in the open position with the springs 79 charged. The latch 85, when pivoted anticlockwise, releases the roller 67 fixed to cam 51 and allows the springs to discharge and cause the contacts to close, through linkage 41, 33, 31. A latch 53 is released on rotation of the trip shaft 63 on the occurrence of an overload in any of the pole units. Compressed contact springs 93 and opening spring 99. Fig, 1, open the contacts and also cause rotation of shaft 35, which is common to all the units. If the springs 79 are recharged in the contact closed position, then, on tripping, the spring 59 connected to the latch 53 resets the circuit breaker so that immediate reclosure is possible. Alternatively, the springs 79 are recharged in the tripped position by means of the motor drive, this also resetting the latch 53. Manual operation mechanism is also provided for tensioning the springs 79.