| 摘要 |
PROBLEM TO BE SOLVED: To enable to obtain a stable tripping operation through skillful matching of motions of a differential shifter mechanism (transmission efficiency of operation outputs) at overload and at an open phase. SOLUTION: The overload/open-phase tripping device for the circuit breaker consists of a differential shifter mechanism linked to a main bimetal of each phase of R, S, and T, and a tripping lever 13 transmitting operation outputs of the differential shifter mechanism to a switching mechanism. The differential shifter mechanism combines a pulling shifter 10, a pulling shifter 11 and a differential lever 12. The differential lever is coupled in pivotal support with the pulling shifter through a coupling pin 14, and is coupled with the pushing shifter through a coupling pin 15 and a guide long hole 10b. In addition to forming of an open-phase output terminal 12b and an overload output terminal 12c of the differential lever separately at two places, a distance L2 from a fulcrum 13a of the tripping lever to the open-phase output terminal 12b is set larger than a distance L1 to the overload output terminal 12c to match moments of force acting on the tripping lever from each output terminal. COPYRIGHT: (C)2005,JPO&NCIPI
|
