JPS58215286A - Holder for electrode chip - Google Patents

Abstract

PURPOSE:To perform uniform adequate spot welding and to improve its quality, by fitfing an electrode holder equipped with an electrode chip rotatably and bringing a work into press contact with the electrode chip uniformly. CONSTITUTION:A subelectrode 10 linked to an upper holder body 3 is fixed to a pin 9, where the electrode holder 8 equipped with the electrode chips 2 is incorporated rotatably. Then, works (a) and (b) are mounted on a back electrode 6 and the holder 3 is lowered to bring electrode chips 2 and 2 which perform welding at two positions at the same time into press contact with the works (a) and (b). When the chips 2 are different in length, the holder 8 rotates and the tip of the short chip 2 also contacts the works (a) and (b) and presses the electrode 6. This holder H for the electrode chips performs uniform adequate spot welding between the works (a) and (b) to improve the quality.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a holder for an electrode tip used in spot welding.

As a conventional electrode tip holder for a spot welding machine, there is one shown in FIG. 1, for example.

The electrode holder 1 has electrode chips 2, 2 attached to the lower surface at required locations symmetrical with respect to a center line C passing through the center thereof, and a tapered portion la is formed at the center of the upper surface, and the tapered portion 1a The upper holder is fitted into the main body 3 and held there.

Back electrodes 6, 6 are placed on the upper surface of the back electrode holder 5 integrally connected to the lower holder main body 4 at a location opposite to the tip 2.2, and are fixed with bolts 1, 1.

Note that the electrode tips 2, 2 can be attached to the electrode holder 1 by drilling taper-shaped tap attachment holes 1b, lb on the bottom surface of the electrode holder 1. The upper parts 2a, 2a are formed in a tapered shape, and the tapered upper parts 2 are formed in the mounting holes 1b, lb.
a and 2a are pushed in and fixed.

In the above configuration, the workpieces b are stacked and placed on the back electrodes 6, 6, and the upper holder main body 8 is lowered to sandwich them between the electrode tips 2, 2 and the back electrodes 6, 6. After welding, spot welding is performed.

However, in such a conventional electrode chip holder, the two electrode chips 2, 2 are connected to the electrode holder 1.
The electrode holder-1 is equipped with an upper holder and a main body 3.
Because of the structure in which the electrode tips 2 and 2 were fixed to each other, there was a difference in the amount of wear at the tips of the two electrode tips 2, and the tip mounting hole
When the areas between b and lb and the upper electrode tips 243 and 2a start to wear out, there will be a difference in height between the tips 2 and 2 even if they are replaced with new electrode tips, and the back electrodes 6 and 6 will There was a problem in that the intervals between the two parts were not the same, and a gap was created in one of the parts during spot welding, resulting in poor welding in one part.

This invention was made by focusing on such conventional problems, and involves attaching an electrode holder equipped with an electrode tip to an upper holder body so as to be rotatable around a horizontal axis, so that both electrode tips can be rotated during welding. The above-mentioned problem has been solved by having a structure in which the workpiece can be evenly pressed against the workpiece by swinging up and down.

An embodiment of the present invention will be described below with reference to FIG. 2 and subsequent figures. Note that the same members as in the conventional example are designated by the same reference numerals, and their explanations will be omitted.

To describe the structure, the electrode tip holder H is an electrode holder 8. It consists of a pin 9 and a sub-electrode 10, and an electrode chip mounting hole 8b is provided on the side of the electrode holder 8.
, 8b, and perpendicular to the center line C. A circular giant through hole 8C is bored in the direction perpendicular to the line connecting the centers of the through holes 8b, and a hole is made from the top of the through hole 8C to the upper surface of the electrode holder 8. A gap 8d is carved along the longitudinal direction of the through hole 8C.

A central hole 8e extending to the through hole 8C is still provided at the center line C of the upper surface of the electrode holder 8. A cylindrical pin 9 is rotatably fitted into this through hole 8C, and a tapered hole 9a is bored at a thick spot in the center of the outer peripheral surface. The sub-electrode 10 has a tapered portion 1a in the lower half of the conventional example.
The upper tapered part 10a is made to have almost the same shape as the upper holder body 3 and is held by the upper part 10a, and the lower half part is the pin 9.
A lower tapered portion 10b is formed which fits into the tapered hole 9a through the central hole 8e. Needless to say, the electrode tips 2.2 are attached to the stopper rod holder 8 through the tip attachment holes 8b, 8b.

Next, the effect will be described.

When the workpieces a and b are stacked and placed on the back electrodes 6 and 6 and a switch (not shown) is turned on, the upper holder main body 3 is lowered and the electrode tips 2 and 2 are placed on the workpiece a and b is pressed against the back electrodes 6, 6. At this time, each electrode tip 2,
If the lengths of the electrode tips 2 are different, the electrode holder 8 uses the tip of the longer electrode tip 2 as a lever operating point and rotates using the center of the pin 9 as a fulcrum, so the tip of the shorter electrode tip 2 also moves. The workpieces a and b are pressed against the back electrode 6 with equal pressure. After pressure welding, a current is applied between the electrode tip 2 and the electrode 6 to perform spot welding.

As described above, according to the present invention, after the electrode holder with two electrode chips attached thereto is rotatably assembled to the pin, the pin is integrally attached to the upper holder main body via the sub-electrode. Because of this structure, during spot welding, even if the lengths of both electrode tips are different, the solid welding point is The same welding conditions can now be obtained, preventing damage such as one side of the welding point peeling off, welding that is worse than polished, or sparks that burn out the workpiece or the tip of the tip. Spot welding is possible, which not only improves quality but also extends the life of each related component.

[Brief explanation of drawings]

FIG. 1 is a partially sectional front view showing the ±center part of a conventional spot welding electrode tip holder, and FIG. 2 is a front view showing the main part of the electrode tip holder of the present invention.
FIG. 3 is an exploded front view of the electrode tip holder of the present invention, FIG. 4 is a side view of the pin, and FIG. 435 is a plan view of the electrode holder. H......Holder for electrode tip 2...
... Electrode tip 3 ... Upper holder - main body 8 ...
...Electrode holder 9...Pin 10...Sub electrode

Claims (1)

[Claims] A holder for an electrode tip used in a spot welding machine, in which a pin is fixed to a sub-electrode connected to the main body of an upper holder, and an electrode holder equipped with an electrode tip for simultaneously welding two points is rotatably assembled to the bottle. .