| 摘要 |
An electromagnetic switch includes a pair of fixed contacts fixed in a contact housing case with a predetermined distance therebetween; a movable contact disposed in the contact housing case to contact to and separate from the pair of fixed contacts; and an electromagnet unit causing the movable contact to contact to and separate from the pair of fixed contacts. The electromagnet unit has a magnetic yoke enclosing an exciting coil, a movable plunger disposed to move through a through hole provided in the magnetic yoke and having a contact pole surface facing the contact pole surface of the magnetic yoke, and a linking shaft linking the movable plunger and the movable contact. The contact pole surface of the movable plunger includes a circular protruding portion having a width narrower than that of a surface facing the magnetic yoke for increasing a magnetic flux density. |
