Circuit breaker

摘要

A circuit breaker having a thermal tripping device comprising a bimetal element and a heater has a holding member attached to the stationary part of the bimetal element, for holding the bimetal element and the heater at respective first end parts thereof. The holding member has an arm connected to a flexible copper wire and generates heat when an over-current flows through it, the arm conducting this heat to the attached end part of the bimetal element to cause the bimetal element to bend and deflect a second end thereof to provide circuit breaking action.