JPH09320379A - Fitting method for electric contact - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the mechanical strength and electrical joining degree of an electric contact by crimping a base plate and contact material together, and thereafter, laser-welding the same. SOLUTION: A hole is provided in a base plate 1 made of an electrical conductor, contact material 2 made of a predetermined electrical conductor is inserted therein, and the contact material 2 is mechanically firmly fixed to the base plate 1 in a crimping process. Laser-welding is conducted between the fringe portion of the back side protrusion portion of the contact portion 2a of the contact material 2 and the base plate 1 so as to form a laser-welded portion 3a. Thereby, the mechanical strength and the electrical joining degree of a joining portion is improved, and reliability is enhanced in an electric contact, and also observation from outside becomes possible at a joining time so that the inspection of the quality of work can be facilitated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of mounting an electric contact used in an electric component (for example, a thermostat).

[0002]

BACKGROUND OF THE INVENTION Contact parts of electrical components are sometimes made by attaching contact material to a base plate. In the prior art, this attachment is performed by a method of crimping a contact material to the base plate by crimping or a method of resistance welding such as spot welding.

[0003]

The contact by crimping tends to have a mechanical holding strength but has a low degree of electrical bonding, and when a large current is applied, contact at the bonding portion between the contact material and the base plate is made. In some cases there was resistance.

Further, the welded contact has a high degree of electrical joining, and even if a relatively large current is passed, there is little problem at the joined portion, but with respect to mechanical holding strength, setting and management of welding conditions are sufficient. Must be done. Mechanical strength also has the contradictory aspect that it cannot be fully evaluated without destructive inspection.

In resistance welding such as spot welding, there is also a problem that the welding nugget is located between the joint surfaces, observation cannot be performed from the outside, and it is difficult to find welding defects.

[0006] It is an object of the present invention to propose a method of attaching an electrical contact, which has a sufficient mechanical attachment strength of the electrical contact, a high degree of electrical joining, and a high reliability of a welded portion.

[0007]

SUMMARY OF THE INVENTION The above object is to mount an electrical contact by combining step A for fixing a contact material on a base plate and step B for laser welding the base plate and the contact material to each other. Solved by

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION In the first embodiment, step A is performed in a pressure bonding step, and step B is performed after step A. In the second embodiment, the process A is performed in the pressure bonding process, and the process A is performed after the process B. In the third embodiment, the process A is performed by resistance welding and the process B is performed.
Is performed after step A.

There are various modes of laser welding of the base plate and the contact material. For example, welding the enlarging part and the base plate when the contact material is crimped, welding the head or body of the contact material and the base plate, or the contact material from the contact part and the base material supporting it. It is also possible to weld between either one of them and the base plate.

The base plate and the contact material are laser-welded at at least one point, but they can also be welded over the entire circumference of the enlarged portion, for example.

In the first form and the second form,
The crimping process ensures the mechanical strength of the bond between the base plate and the contact material, and the laser welding ensures the electrical connection between the base plate and the contact material.

Nuggets in resistance welding such as spot welding exist between joint surfaces, and it is generally difficult to inspect the quality of the welding. However, in the third form,
Since the laser welded portion can be observed from the outside, the quality of the welding can be easily inspected and the reliability of the welding can be improved.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a base plate 1 made of an electric conductor having a hole, and a contact material 2 made of a relatively soft electric conductor having electrical and chemical durability is inserted into the hole and a crimping process is performed. It is sectional drawing when the 1st process of fixing the contact material 2 to the base plate 1 by it is completed.

It can be seen that by the crimping process, the contact material 2 is deformed and the contact material 2 is mechanically fixed to the base plate 1, and the contact material 2 is also electrically connected to the base plate 1.

However, it is preferable to make the electrical contact between the base plate 1 and the contact material 2 more reliable.

FIG. 2 is a cross-sectional view when laser welding is performed between the base plate 1 and the peripheral portion of the convex portion 2b on the back side of the contact portion 2a of the contact material 2 and the base plate 1 of FIG. Contact material 2 and base plate 1
A laser welded portion 3a is formed between the two, and the two are electrically and reliably joined together. In addition, it is easy to inspect the quality of welding.

FIG. 3 is a sectional view when laser welding is performed between the base plate 1 and the peripheral portion of the contact portion 2a of the contact material 2 and the base plate 1 of FIG. The laser welded portion 3b is formed as in FIG. 2, and the quality of welding can be easily inspected.

FIG. 4 shows that the laser beam L is applied to the base plate 1 from the direction of the back side of the base plate 1 and the contact portion 2a of the contact material 2 in FIG. FIG. 4 is a cross-sectional view when the base plate 1 and the contact material 2 are melted by laser welding.

FIG. 5 shows the base plate 1 of FIG. 4 and the convex portion 2 of the contact material 2.
It is the front view seen from the b side. In this embodiment, the contact portion 2
Laser welded portions 3c are formed at four locations on the peripheral edge of a. Inspection of welding quality is also easy.

FIG. 6 shows that, when the contact material 2 is composed of the contact portion 2A and the base material 2B supporting the contact portion 2A, the base material 2B is inserted into the hole of the base plate 1 and then crimped, and further the peripheral edge of the base material 2B. It is a sectional view when performing laser welding of the portion to the base plate 1. As in the case of FIG. 2, the laser welded portion 3d is formed,
Also, the inspection of the welded portion 3d is easy.

The base plate 1 and the contact material 2 shown in FIGS. 2, 3, 4, 5, and 6 can be joined by laser welding first and then a crimping step. .

FIG. 7 is a cross-sectional view when the contact material 2 is fixed to the base plate 1 by resistance welding such as spot welding, and then the peripheral edge portion of the contact material 3 is laser-welded to the base plate 1. The welded nugget 4 is located between the joint surfaces and cannot be observed from the outside. Since the laser weld 3e can be observed from the outside, it is easy to inspect the quality of welding. Since two types of welding are performed, the welding reliability is high.

[0023]

【The invention's effect】

(1) In the case of the combination of the crimping process and the laser welding, the mechanical strength of the joint is large and the electric connection is ensured. In addition, it is easy to inspect the quality of welding. (2) When resistance welding such as spot welding and laser welding are combined, the welding reliability is high and the welding inspection is easy.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a base plate 1 and a contact material 2 when only a crimping process is performed.

FIG. 2 is a cross-sectional view of an example when laser welding is performed after the crimping step of FIG.

FIG. 3 is a cross-sectional view of another example in which laser welding is performed after the crimping step of FIG.

FIG. 4 is a cross-sectional view of yet another example in which laser welding is performed after the crimping step of FIG.

FIG. 5 is a front view of FIG. 4;

6 is a cross-sectional view of a base plate and contact material corresponding to FIG. 2 when the contact material 2A is composed of a contact portion 2A and a base material 2B.

FIG. 7 is a cross-sectional view of the base plate and the contact material when the base plate and the contact material are joined by resistance welding such as spot welding and then laser welding is performed.

[Explanation of symbols]

 1 base plate 2 contact material 2a contact portion 2b convex portion 2A contact portion 2B base material 3a, 3b, 3c, 3d, 3e laser welded portion 4 nugget

Claims (4)

[Claims] 1. A first material for inserting a contact material into a through hole of a base plate.
And a second step of crimping the contact material to the base plate after the first step, and a third step of laser welding at least one point of the contact material to the base plate after the second step. A method for mounting an electrical contact, characterized by comprising steps. 2. In the laser welding, the base plate is melted by a laser beam to form a through hole in the base plate, and the base plate and a part of the contact material are partially removed on the surface of the base plate on the back side of the laser irradiation surface. The method of mounting an electrical contact according to claim 1, wherein laser welding is performed. 3. The first contact material is inserted into the through hole of the base plate.
The second step of laser welding at least one point of the contact material to the base plate after the first step, and the third step of crimping the contact material to the base plate after the second step. A method for mounting an electrical contact, characterized by comprising steps. 4. The first contact material is inserted into the through hole of the base plate.
And a second step of fixing the contact material to the base plate by resistance welding after the first step, and laser welding at least one point of the contact material to the base plate after the second step. A method for mounting an electrical contact, comprising a third step.