| 摘要 |
In the present invention, a circuit breaker can be miniaturized by miniaturizing an electromagnetic wave trigger affected by inverse time characteristics while maintaining the suction force of the electromagnetic wave trigger in the circuit breaker. The circuit breaker is provided with a movable contact (24), a fixed contact (21), a power supply-side terminal (20), a gating mechanism unit (30), and an electromagnetic wave trigger (40). The fixed contact (21) is capable of coming into contact with the movable contact (23). The power supply-side terminal (20) is connected to the fixed contact. The gating mechanism unit (30) opens and closes the movable contact (24). The electromagnetic wave trigger (40) triggers the gating mechanism unit (30), and is connected to the movable contact (24). The electromagnetic wave trigger (40) includes a yoke (42), an oil dashpot (43), and a movable iron piece (49). The yoke (42) is made of a magnetic sheet. The oil dashpot (43) is fixed to one leg of the yoke (42). The movable iron piece (49) is turnably held in the other leg of the yoke (42). The electromagnetic wave trigger includes a first attraction surface (49a) facing an armature surface of the oil dashpot (43). The movable iron piece (49) is provided with a second attraction surface (49e). |
