Patent ID: 8937518
Filing Date: 2015-01-20
Classification: H01H

Abstract:
1. An electromagnetic switch, comprising: a contact device having a pair of fixed contacts maintaining a predetermined interval therebetween and fixed inside an arc extinguishing chamber housing, and a movable contact disposed to be capable of contacting with and separating from the pair of fixed contacts; and an electromagnetic device having a movable plunger moving between an opened position wherein the movable contact separates from the fixed contacts and a closed position wherein the movable contact contacts with the fixed contacts to press down, wherein the arc extinguishing chamber housing is provided with permanent magnets to extinguish an arc generated at an opening time when the movable contact separates from the fixed contacts from a state in the closed position in which the movable contact contacts with the fixed contacts, the magnetic circuit comprises in a state in which the movable plunger is in the opened position, a magnetic circuit is formed starting from the permanent magnets and returning to the permanent magnets through the first and second magnetic yokes and the movable plunger.