JPS6222211B2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method of manufacturing an electrical contact.

Although various types of electrical contacts have been used in the past, there are two types of electrical contacts that are most commonly used: one using a single-ended contact and one using a double-ended contact. Among them, those using single-headed contacts are manufactured by resistance welding as follows. First, as shown in FIG. 1, a contact strip 3 having flanges on the left and right outer sides, a contact protrusion 1 having a trapezoidal cross section on its upper surface, and a protrusion 2 at the center of its lower surface is constructed as shown by the dashed line. Cut it to length to make the contact material 3'. Next, this contact material 3' is stacked on the tip of the spring terminal material 4 at the required position as shown in FIG. 4 are resistance welded via projection. here,
"Contact protrusion" refers to a highly protruding part of the contact surface of an electrical contact. The same applies hereafter. Furthermore, one type of electric contact using a single-headed contact is a movable contact for a governor mechanism for a micromotor. Although the manufacturing method of this contact is not shown, it involves resistance welding a contact protrusion with a trapezoidal cross section and a contact material with only a protrusion without a flange to a spring terminal material to which a governor weight has been resistance welded in advance. be. On the other hand, an electronic contact using a double-ended contact is manufactured as follows. First, in the same manner as in the manufacturing method using a single-headed contact, the contact material 3' is resistance welded to a desired position on the tip of the spring terminal material 4 via projection as shown in FIG. Next, the contact material 3'' is placed on the other surface of the tip of the spring terminal material 4, and this is inserted between the upper and lower electrodes 5, 6' of the resistance welding machine as shown in FIG. '' and a spring terminal material 4 are resistance welded together via a projection 2.

The electrical contacts obtained by these methods all suffer from slight wobbling due to downward pressure of the upper electrode 5 during welding, and from melting of the projection 2 of the contact material 3' or 3'' and causing the contact material to slip. As a result, the contact material 3' or 3'' is resistance welded with a slight deviation. Even this slight misalignment greatly affects the performance of the electrical contact because the contact material 3' or 3'' shakes during the opening/closing operation of the electrical contact.Furthermore, if resistance welding is performed with misalignment, the contact material 3' or 3'' If the bonding strength between the spring terminal material 4 and the spring terminal material 4 is unstable, and the resistance welding is particularly poor at double-ended contacts, the contact material 3' or 3" may come off during the opening/closing operation of the electric contact. If too much current is applied, the spring terminal material 4 may be deformed due to the influence of heat or the spring characteristics may become uneven, causing malfunction.

On the other hand, as electronic devices, communication devices, etc. have become smaller and smaller in recent years, the electronic contacts used in these devices have also become smaller, and electrical contacts with extremely high dimensional accuracy are required to meet the harsh usage conditions. It has come to be.

However, in the conventional resistance welding method, the contact material 3' or 3'' is connected to the spring terminal material 4 as described above.
The reality is that it is extremely difficult to perform resistance welding at the required positions with good dimensional accuracy, making it impossible to obtain small, high-quality electrical contacts with high dimensional accuracy. For example, if resistance welding is performed with misalignment occurring, the spring terminal material 4 has a machining history, so heat will not be transferred uniformly, and the terminal material 4 will warp. For this reason, when used for the opening and closing operations of small switches, a disadvantage arises in that the spring characteristics vary.

In addition, when manufacturing double-ended electrical contacts,
Resistance welding twice takes a lot of time and money, increases misalignment, and makes it easier to peel off. Therefore, various measures have been taken to prevent the contact material 3'' from peeling off, such as changing the current value when resistance welding is applied to the other surface of the tip of the spring terminal material 4, but it is still difficult to completely prevent the contact material 3'' from peeling off. The reality is that it is not possible.

The present invention has been made in view of the above circumstances, and even in the case of a small electric contact, the contact material is polymerized so that it is exposed on both sides of the spring terminal material, and resistance welding is performed at the brim portion of the contact material through projection. The present invention provides a method for manufacturing electrical contacts with high dimensional accuracy and good quality.

The manufacturing method of the present invention is a method of manufacturing an electric contact in which a contact material having a contact protrusion having a trapezoidal cross-sectional shape and having rib portions on the left and right outer sides is resistance welded to a spring terminal material. After inserting and fitting the contact protrusion of the contact material into the notch or hole and positioning and overlapping the bottom of the contact protrusion with the side wall of the notch or hole, an electrode having a U-shaped cross section that has a cavity larger than the contact protrusion. This is a method of manufacturing an electric contact, which is characterized in that resistance welding is performed at the brim of the contact material through projection using the contact material.

In particular, the manufacturing method of the present invention provides a double-headed contact material having flanges on the left and right outer sides and contact protrusions having a trapezoidal cross-section on both upper and lower surfaces, and the height of the upper and lower contact protrusions is that of a spring terminal. Materials that differ only in thickness can be used.

Hereinafter, an example of the method for manufacturing an electric contact according to the present invention will be explained based on the drawings. First, a wire is processed to make a contact band material 12 having a contact protrusion 11 and a collar 11' with a trapezoidal cross section on one side as shown in FIG. 4, and then cut to a required length to form a contact material 12'. . Next, the fifth
As shown in the figure, a notch 14 having the same dimensions as the base external dimension of the contact protrusion 11 of the contact member 12' or a hole 15 as shown in FIG. 6 is provided at a predetermined position at the tip of the spring terminal member 13. Next, the trapezoidal contact protrusion 11 of the contact material 12' is inserted and fitted into the notch 14 or hole 15 of the spring terminal material 13 to form the contact protrusion 1.
1 by positioning and superposing the bottom part of the cutout 14 or the side wall of the hole 15. Next, as shown in FIG. 7, the contact material 12' and the spring terminal material 13 which have been positioned and overlapped are moved to a lower electrode 17 having a U-shaped cross section and having a cavity larger than the upper electrode 16 of the resistance welding machine and its contact protrusion 11. The upper electrode 16 is lowered to pressurize the projection between the collar 11' of the contact member 12' and the spring terminal member 13, and at the same time, current is applied between the upper and lower electrodes 16 and 17. Contact material 1
2' and the spring terminal material 13 to the contact protrusion 11.
Make electrical contacts by resistance welding on the sides.
Incidentally, although a projection is not shown in FIG. 7, a projection 26 is provided on the contact member 12' or the spring terminal member 13 as shown in FIG. 13 or 14.

According to the manufacturing method of the electric contact made in this way, since the cross section of the contact protrusion 11 is trapezoidal, it is easy to insert and fit, and when the contact material 12' and the spring terminal material 13 are resistance welded, the contact material 12 Since the bottom of the contact protruding part 11 ' is positioned by the notch 14 or the side wall of the hole 15 at a predetermined position at the tip of the spring terminal material 13, even if the upper electrode 16 is slightly shaken when downward pressure is applied, the contact will not change. The material 12' and the spring terminal material 13 are resistance welded to a desired position without shifting, resulting in high dimensional accuracy. In addition, since the contact material 12' is resistance welded at the flange 11', and the lower electrode 17 has a U-shaped cross section with a cavity larger than the contact protrusion 11, the contact surface of the electrical contact during resistance welding It does not contaminate the water. Further, since only a small area of the spring terminal material 13 is resistance welded by a small current by the projection 26, the spring characteristics of the spring terminal material 13 are not impaired. It should be noted that in the electrical contact resistance welded in this way, the contact material 12' is exposed on both sides of the spring terminal material 13, so it is different from the conventional one in which the contact material 12' is attached to only one side of the spring terminal material 13. Compared to the manufacturing method, stable spring characteristics can be obtained when the other end of the spring terminal material 13 is fixed and the opening/closing operation is performed.

Next, a case will be described in which a double-ended electrical contact is manufactured by the manufacturing method of the present invention. First, a wire is processed to make a contact strip 18 having trapezoidal contact protrusions 11a, 11b and a collar 11' on both upper and lower surfaces as shown in FIG. do. One of the contact protrusions 11a of the contact material 18' is made as high as the thickness of the spring terminal material 13, and the inclination angles on both sides thereof are changed to make the area of the top surface equal to the area of the top surface of the other contact protrusion 11b. It is set as. This contact member 18' has one contact protrusion 11a having a trapezoidal cross section inserted into the notch 14 of the spring terminal member 13 shown in FIG. 5 or the hole 15 of the spring terminal member 13 shown in FIG. 6 to position both. Polymerize. Next, this positioning polymerized contact material 1
8' and the spring terminal material 13 are inserted between the upper and lower electrodes 16' and 17, which have a U-shaped cross section and have a cavity larger than the contact projections 11a and 11b, as shown in FIG. 9, and the electrode 16' is lowered. Pressure is applied to the projection between the contact material 18' and the spring terminal material 13, and at the same time electricity is applied between the upper and lower electrodes 16' and 17 to cause the contact material 18' and the spring terminal material 13 to protrude as a contact with a trapezoidal cross section. Resistance welding is performed on the sides of portions 11a and 11b to create a double-ended electrical contact. Incidentally, although the projection is not shown in FIG. 9, the contact material 12' or the spring terminal material 13 is provided with a projection as shown in FIG. 13 or 14.

The method for manufacturing a double-sided electrical contact produced in this manner has the same effect as that for a single-sided contact.
Furthermore, since it is possible to form a double-headed contact similar to the conventional method with one resistance welding, contact materials 3' and 3'' are attached to both sides of the tip of the spring terminal material 4, respectively, as in the conventional method shown in FIG. No need for resistance welding
Extremely efficient production. In addition, this double-headed contact material 1
The heights of the upper and lower contact protrusions 8' differ by the thickness of the spring terminal material, thereby stabilizing the opening/closing operation of the resistance welded electric contact. In the conventional method,
When the contact material 3'' was resistance welded to the other surface of the tip of the spring terminal material 4, the contact material 3'' often came off, but the manufacturing method of the present invention eliminates such defects. is completely eliminated.

The manufacturing method of the present invention for manufacturing a single-headed electrical contact can also be applied to manufacturing a movable electrical contact for a governor mechanism for a micromotor. That is, first, as shown in FIG. 10, a contact member 22 having a movable contact 20, which is a contact protrusion with a trapezoidal cross section, on one side and a governor weight 21, which is a flange, on the other side, is made.
As shown in FIG. 1, a hole 23 having the same external dimensions as the movable contact 20 of the contact material 22 is provided at a predetermined position at the tip of the spring terminal material 13, and the trapezoidal cross section of the hole 23 of the spring terminal material 13 and the contact material 22 is formed. The contact material 22 and the spring terminal material 13 are positioned and overlapped by fitting with the movable contact 20. Next, the contact material 22 and the spring terminal material 13 are assembled by positioning and overlapping.
As shown in FIG. 12, the movable contact 20 is inserted between the upper electrode 24 and the lower electrode 25, each having a U-shaped cross section and a hollow portion larger than the movable contact 20, which is the contact protrusion, and the upper electrode 24 is lowered. Pressure is applied to the projection between the and spring terminal material 13, and at the same time, current is applied between both the upper and lower electrodes 24, 25 to connect the contact material 22 and the spring terminal material 13 via the projection. Movable contact 20
Resistance welding is performed on the side of the electrode to create a movable contact for the governor mechanism for the micromotor. Incidentally, although a projection is not shown in FIG. 12, a projection 26 may be provided as shown in FIG. As shown in FIG. 14, a projection can be provided outside the hole 15 or notch 14 of the spring terminal member 13.

According to the method of manufacturing the movable contact of the governor mechanism for a micromotor thus manufactured, the same effects as the method of manufacturing the electric contact using the single-headed contact described above can be obtained.

As is clear from the above, according to the manufacturing method of the present invention, the contact protrusion having a trapezoidal cross section can be easily inserted and fitted into the notch or hole of the spring terminal material, and the position can be determined by the side wall of the notch or hole. Easy and accurate positioning. In addition, since resistance welding is performed at a location different from the location where it was positioned, there is no misalignment due to thermal deformation at the location where it was positioned, and because projection allows resistance welding to be performed on only a minute area with a minute current, there is no possibility of damaging the spring characteristics of the spring terminal material. do not have. Further, since an electrode having a U-shaped cross section having a cavity larger than the contact protrusion is used, the contact surface of the contact is not contaminated.

In addition to these effects, in the case of the manufacturing method for double-headed electrical contacts, there is no need to perform resistance welding twice, and the opening and closing operations of the electrical contacts are stable, similar to the conventional method. Therefore, it is possible to improve manufacturing efficiency. Furthermore, in the case of manufacturing double-ended contacts, the conventional method had the disadvantage that the contact material peeled off when the contact material was welded to one side and then resistance welded to the other, but this defect was completely eliminated. There is an effect that it can be done.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of a conventional contact strip material, Fig. 2 is a sectional view showing the state of resistance welding of a contact material and a spring terminal material when making an electric contact by the conventional manufacturing method, and Fig. Figure 3 is a cross-sectional view showing the state of resistance welding between contact material and spring terminal material when making a double-headed electrical contact using the conventional manufacturing method, and Figure 4 shows the contact used in the manufacturing method of the present invention. A perspective view of the strip material, FIGS. 5 and 6 are a plan view showing the spring terminal material used in the manufacturing method of the present invention, and FIG.
The figure is a sectional view showing the state of resistance welding between a contact material and a spring terminal material when making an electric contact by the manufacturing method of the present invention, and Figure 8 shows a contact for a double-headed contact used in the manufacturing method of the present invention. FIG. 9 is a perspective view of the strip material, FIG. 9 is a cross-sectional view showing the state of resistance welding between the contact material and the spring terminal material when making a double-headed electrical contact by the manufacturing method of the present invention, and FIG. A perspective view of a contact material used in manufacturing a movable electric contact of a governor mechanism for a micromotor by the manufacturing method of the present invention, 1st
Fig. 1 is a perspective view of a spring terminal material for attaching the contact material, and Fig. 12 shows the contact material and spring terminal material when a movable electric contact for a governor mechanism for a micromotor is manufactured by the manufacturing method of the present invention. Fig. 13 is a perspective view of a contact material in which a protrusion is provided on the outside of the contact protrusion, and Fig. 14 is a cross-sectional view showing the state during resistance welding. It is a perspective view of the spring terminal material. 11, 11a, 11b...Contact protrusion, 11'
...Brim portion, 12'... Contact material, 13... Spring terminal material, 14... Notch, 15... Hole, 26...
...Projexion.

Claims (1)

[Scope of Claims] 1. A method for manufacturing an electric contact in which a contact material having a contact protrusion having a trapezoidal cross section and having ribs on the left and right outer sides is resistance welded to a spring terminal material, in which a notch in the spring terminal material is provided. Alternatively, after inserting and fitting the contact protrusion of the contact material into the hole and positioning and overlapping the bottom of the contact protrusion with the notch or side wall of the hole, an electrode having a U-shaped cross section having a cavity larger than the contact protrusion is formed. 1. A method of manufacturing an electric contact, which comprises using the contact material to perform resistance welding at the brim portion of the contact material through projection. 2. A double-headed contact material that has flanges on the left and right outer sides and contact protrusions with trapezoidal cross sections on both the top and bottom surfaces, and the heights of the upper and lower contact protrusions differ by the thickness of the spring terminal material. 2. A method of manufacturing an electrical contact according to claim 1, characterized in that an electrical contact is used.