Snap drive for contacts of circuit breaker - has motor tensioning retractable spring via reducer gear work for sudden release recoil action

摘要

The snap-action drive for movable contacts of a circuit breaker has a motor driving a retractable spring via reducing gear-work. The spring engages an edge of a flywheel (2) connected to the reducer gear work (3) through a free-wheeling clutch (4). The flywheel has two pins (5,6) which can drive a linkage (8-10) connected with the movable contacts. A circuit break demand starts the motor (19). The rotation tensions a coiled spring. Further rotation moves the flywheel (2) anti-clockwise. This tensions the retractable spring. So soon as the max. tension of the latter is reached it unwinds and throws the flywheel. The pin (5) impacts the rod (8) and forces it upwards. The rod (9) is forced to the left and the switching rod is pulled out from the opposing contact via linkage rod (10).