JPH0241811Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Field of Application> The present invention relates to a structure for improving the movable contact of a magnetic switch for a starter for an internal combustion engine.

<Prior Art> Conventionally, as shown in FIG. 2, such a plunger structure is formed by cutting a pin above the plunger 15 that slides within the bobbin of an electromagnetic coil, and inserting an insulating collar 16 into the pin 15a. Furthermore, after inserting the movable contact 8 and the contact spring 7 into the collar 16,
An insulating washer 18 and a flat washer 17 are assembled, and the ends of pins 15a of the plunger are caulked to fix the washers 17 and 18 to the insulating collar 16. In such a structure, the small diameter pin portion 15a through which the insulating collar is inserted is connected to the plunger 1.
5, it had to be cut from its outer diameter, resulting in a lot of material loss and high costs.

<Problems to be solved by the invention> 1. The present invention aims to eliminate material loss by making the pin part, on which the plunger body and the movable contact are assembled, larger in diameter than in the past, and 2. to transfer the heat generated in the movable contact to the pin side. To achieve heat dissipation effect.

3. The purpose is to provide insulation between the pin and the plunger so that the current of the movable contact is not transmitted to the plunger via the pin.

<Means for Solving the Problems> The present invention provides an electromagnetic switch in which a plunger is attracted by excitation of an electromagnetic coil, and a movable contact attached to the plunger and a fixed contact fixed to an insulating cover are brought into contact and separated, A metal guide pin 4, through which a movable contact 8 is slidably inserted, is connected to a plunger 10 via an insulating collar 5 in a non-contact manner.

<Example> The following description will be made based on the illustrated embodiments.

Fig. 1 shows an electromagnetic switch for starting a starter motor for a vehicle, in which an electromagnetic coil 3 is installed inside a switch case 1 made of a magnetic material, and when an excitation current flows through the electromagnetic coil 3, a plunger 10 equipped with a movable contact 8 is activated. The movable contact 8 is attracted by the magnetic path made up of the switch case 1 and the yoke 12 and moves downward, and the fixed contact 6 fixed to the insulating cover 2 via the contact bolt 9 collides with the movable contact 8 to close the circuit of the starter motor. do. The plunger mechanism of the present invention has a movable contact part and a plunger 10 as separate bodies, and a contact spring 7 and a movable contact 8 are connected to a metal guide pin 4 with a locking part at the upper end.
A resin insulating collar 5, which regulates the downward movement of the movable contact 8 and connects the plunger 10 and the guide pin 4 in a non-contact state, is inserted under the pin 4 and protrudes from the guide. The tip of the pin 4 is caulked and fixed within a recess formed inside the overhang 5a of the insulating collar 5 via a flat plate 11. Then, the integrally assembled movable contact part is fitted into the upper end recess of the plunger 10, and the peripheral edge of the projecting part 5a of the insulating collar 5 is caulked with the upper edge of the plunger to couple the movable contact part and the plunger 10. 13 in the diagram
is a coil bobbin, and 14 is a return spring.

<Effects of the invention> Since the present invention is configured as described above, the movable contact is inserted directly into the upper large diameter portion of the guide pin 4 so that the heat generated in the movable contact is radiated to the pin side, and the metal guide pin 4 and plunger 1
The insulation collar 5 that measures the insulation of the guide pin 4
A flat plate 1 is attached to the tip of the pin that protrudes while being supported on the step part with a slightly smaller diameter than the movable contact insertion part on the lower side.
1 is inserted through the guide pin 4 and fixed by caulking, the small diameter portion of the guide pin 4 only needs to be cut to a small diameter that forms a step that prevents the insulating collar 5 from slipping upward. However, the small diameter pin part has the effect of reducing the amount of cutting and preventing material loss.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional front view of an electromagnetic switch according to an embodiment of the present invention, and FIG. 2 is a sectional view of a conventional plunger. 3... Electromagnetic coil, 4... Guide pin, 5...
Insulation collar, 6... Fixed contact, 8... Movable contact,
10... Plungiya.

Claims (1)

[Scope of utility model registration request] In an electromagnetic switch in which a plunger is attracted by the excitation of an electromagnetic coil, and a movable contact attached to the plunger and a fixed contact fixed to an insulating cover are brought into contact and separated, a metal guide is slidably inserted through the movable contact 8. An electromagnetic switch characterized in that a pin 4 is connected to a plunger 10 through an insulating collar 5 in a non-contact manner.