IP Library Granted Patent US 9,484,173
Granted Patent B2
US 9,484,173 · App. 14/677,047 · Granted Nov 1, 2016

Electromagnetic switch with increased magnetic flux density

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Quick Facts
Patent No.
US 9,484,173
App. No.
14/677,047
Granted
Nov 1, 2016
Kind
B2
Abstract

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.

Claims (14)

1. An electromagnetic switch, comprising:

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,

wherein 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 peripheral flange portion which extends radially outwardly and a contact pole surface formed at the peripheral flange portion and facing a contact pole surface of the magnetic yoke, and a linking shaft linking the movable plunger and the movable contact, and

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.

2. The electromagnetic switch according to claim 1 , wherein the circular protruding portion is formed in an annular shape.

3. An electromagnetic switch, comprising:

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,

wherein 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 a 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, and

the circular protruding portion is formed on an outer peripheral side of a peripheral flange portion formed on the movable plunger.

Assignments (2)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 23, 2017
From: FUJI ELECTRIC CO., LTD.
To: FUJI ELECTRIC FA COMPONENTS & SYSTEMS CO., LTD.
Reel/Frame 043919/0072 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Apr 2, 2015
From: NAKA, YASUHIRO; TAKAYA, KOUETSU; SUZUKI, KENJI
To: FUJI ELECTRIC FA COMPONENTS & SYSTEMS CO., LTD.; FUJI ELECTRIC CO., LTD.
Reel/Frame 035319/0679 →