JP2000027741A - Electromagnetic switch for starter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electromagnetic switch for a starter which secures dust and water prevention in a moving core sliding part and a contact chamber, shown satisfactory sealability and assembling property, and attains reduction in cost, size and weight. SOLUTION: In an electromagnetic switch for a starter, a moving core 5 has a moving core main body 5a integrated with a stepped small diameter portion 5b having a shift lever engagement portion 5c at its end. A cup-like holder 6 has a flange 6a and a center hole 6b having an end to which rubber is baked to attach it. A contact portion 6c to which rubber is baked to attach it is formed on the surface of the flange 7a which is abutted against a plate 4 of a yoke 1 through that the moving core main body 5a slidably penetrates. A cover 9 is locked by a retaining ring 8 fitted in a retaining ring groove 7 formed on substantially a center portion of the stepped small diameter portion. A return spring 10 is elastically repulsively engaged between a flange portion 9a installed at an outer periphery of the cover 9 and the flange 6a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproof and dustproof seal for an electromagnetic switch for a starter, which slides a starter pinion gear on a pinion shaft in a starter for starting an engine of a large vehicle such as a truck or a bus. Regarding improvement.

[0002]

2. Description of the Related Art Conventionally, for example, Japanese Utility Model Application Laid-open No.
As disclosed in Japanese Patent No. 3940, a flexible boot is mounted between the case end and the moving core operating rod to protect the sliding portion of the moving core against dust.

[0003]

The conventional boot has a complicated boot shape, which is one factor of high cost, and also requires a reduction in assembling time in terms of assemblability. The present invention has been made in view of such circumstances, and provides an electromagnetic switch for a starter that ensures waterproof and dustproof properties of a moving core sliding portion and a contact chamber, has good sealing properties, is easy to assemble, and can be expected to reduce costs. That is the task.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a moving core having a stepped small-diameter portion having a shift lever engaging portion at an end and a moving core body integrally formed with a flange portion. A cup-shaped holder having a center hole in which rubber is baked at an end portion, and a contact portion in which rubber is baked is formed on a surface of the flange portion which abuts a plate of a yoke through which the moving core body slidably passes. A cover locked by a retaining ring fitted into a retaining ring groove provided at a substantially central portion of the stepped small-diameter portion, and between a flange provided on an outer periphery of the cover and the flange. A technical means comprising a return spring which is resiliently engaged with is adopted.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The embodiments of the present invention will be described below based on one embodiment of the present invention shown in the accompanying drawings.

FIG. 1 is a partial sectional view of an electromagnetic switch for a starter. A bobbin 2 is coaxially provided inside the yoke 1.
A moving core 5 is slidably provided on the inner periphery of the bobbin 2 with one end penetrating through the plate 4 of the yoke 1. The moving core 5 has a stepped small diameter portion 5b at a penetrating end of the plate 4 of the moving core body 5a and a shift lever engaging portion 5c of a starter at the tip.
However, a contact shaft portion 5d is integrally formed on the other end side. Stepped small diameter part 5 of moving core 5
A cup-shaped holder 6 having a flange 6a at the end and a center hole 6b is fitted into b, and is mounted so as to include the moving core body 5a. Rubber is baked at the end of the center hole 6b, and the inner peripheral surface thereof is slidable in contact with the outer peripheral surface of the stepped small diameter portion 5b of the moving core 5.

Further, rubber is also baked on the surface of the holder 6 where the flange 6a comes into contact with the plate 4, so that the contact 6c is formed.
Is formed. A retaining ring groove 7 is provided substantially at the center of the stepped small diameter portion 5b of the moving core 5.
The cover 9 is locked by the retaining ring 8 fitted into the retaining ring groove 7, and the return spring 10 is elastically engaged between the cover 9 and the flange 6 a of the holder 6. The cover 9 has a circular recess having a hole into which the stepped small-diameter portion 5b of the moving core 5 is inserted, and a flange 9a is formed on the outer periphery of the recess to receive the return spring 10. Has become.

A stationary core 11 having a central hole coaxially is engaged with the other end of the yoke 1, and the contact shaft portion 5d of the moving core 5 is slidably loosely fitted in the central hole. A contact portion 12 is slidably provided at the tip of the contact shaft portion 5d, and a bowl-shaped contact cover 13 is provided on the yoke 1 so as to close the contact portion 14 as an internal space so as to surround and bend the contact portion 12. Engaged. The contact cover 13 is provided with first and second fixed contacts 16 and 17.

When the DC voltage is applied to the coil 3 to excite it, the moving core 5 is attracted in the direction of the arrow in FIG. 1 against the elastic force of the return spring 10, and the supply of the DC voltage is cut off. The moving core 5 is moved in the direction opposite to the direction of the arrow by the elastic force of the compressed return spring 10 and returned to the original position.

The moving core of the electromagnetic switch is assembled with the center hole 6 of the holder 6 in the moving core 5.
b so as to slide into the stepped small diameter portion 5b, and the holder 6
One end of the return spring 10 is mounted on the flange portion 6a. The cover 9 is inserted into the moving core 5 and the cover 9
The other end of the return spring 10 is brought into contact with the flange 9a of the moving core 5, and the retaining ring 8 is fitted into the retaining ring groove 7 provided in the stepped small diameter portion 5b of the moving core 5 while pressing the cover 9. When the cover 9 pressed is released, the cover 9 is pushed back by the elastic force of the return spring 10 which has been compressed, and the retaining ring 8 is pressed.
Is stored in the recess of the cover 9.

[0011]

According to the present invention, there is provided a moving core in which a stepped small diameter portion having a shift lever engaging portion at an end thereof and a moving core body are integrally formed, and a center hole having a flange and an end burned with rubber. A cup-shaped holder, and a contact portion made of rubber baked on a surface of the flange portion that abuts a plate of a yoke through which the moving core body slidably penetrates, and a substantially central portion of the stepped small-diameter portion. A cover locked by a retaining ring fitted into a retaining ring groove provided on the cover, and a return spring resiliently engaged between a flange provided on an outer periphery of the cover and the flange. As a result, it is easy to assemble while maintaining the dustproof and waterproof properties of the sliding part and the contact chamber where the moving core slides by exciting the coil, and the number of parts is reduced. The cost can be reduced by. In addition, the diameters of the flange portion, the flange portion of the cover, and the return spring can be reduced, which can contribute to reduction in size and weight.

[Brief description of the drawings]

FIG. 1 is a partial sectional view of an embodiment according to the present invention.

[Explanation of symbols]

 1 ... Yoke 4 ... Plate 5 ... Moving core 5a ... Moving core body 5b ... Stepped small diameter portion 5c ... Shift lever engaging portion 6 ····· Holder 6a ··· Flange part 6b ···· Central hole 6c ··· Contact part 7 ··· Retaining ring groove 8 ··· Retaining ring 9 ..Cover 9a .... Flange 10 ... Return spring

Claims (1)

[Claims] An electromagnetic switch for a starter that slides a pinion gear on a pinion shaft via a shift lever, wherein the stepped small diameter portion (5b) having a shift lever engaging portion (5c) at an end and a moving core body (5). A moving core (5) integrally formed with 5a) and a flange (6);
a) and a cup-shaped holder (6) having a central hole (6b) in which rubber is baked at an end, and a plate (4) of a yoke (1) through which the moving core body (5a) slidably passes. A contact portion (6c) formed by sintering rubber is formed on the surface of the flange portion (6a) to be in contact with the flange portion (6a). A cover (9) locked by a retaining ring (8) to be fitted, and a flange (9a) provided on the outer periphery of the cover (9) and the flange (6a) resiliently. An electromagnetic switch for a starter, comprising a return spring (10) to be engaged.