JPS5837070B2 - Electrode structure of electric welding machine - Google Patents

Description

Detailed Description of the Invention The present invention provides an L-shaped step 3 on one side of the electrode surface 2 on the lower surface of the upper electrode 1, and electrically welds the welded body 5 to the welded body 5 placed on the upper surface of the lower electrode 4. The predetermined value A is determined from the height of the workpiece 6 to be welded.
The present invention relates to an electrode structure for an electric welding machine characterized in that the depth of the stepped portion 3 is set to be shallow.

A conventional electric welding machine, such as a projection welding machine, is shown in FIG.

That is, an object 6 to be welded, such as a nut, is placed on the upper surface of the welding body 5 (so-called workpiece) placed on the flat electrode surface 23' on the upper surface of the lower electrode 4', and 2
' are brought into contact with the upper surface of the workpiece 6, and the respective electrodes 1' and 4'
The workpiece 6 is welded to the welding body 5 by the Joule heat generated at the contact portion between the welding body 5 and the workpiece 6.

However, in conventional electric welding machines, each electrode 1', 4
' Since the electrode surfaces 2' and 2a' are flat, the welded body 5
When welding two objects to be welded 6, which are installed close to the top surface, to the welding body 5, the electrode surface 2' of the upper electrode 1' comes into contact with the top surface of each of the objects to be welded 6, 6, and the current is applied to each object. Object to be welded 6,6
This has the disadvantage that the current per piece becomes smaller and the welding force becomes weaker, and since the contact resistance between the welded objects 6, 6 and the welded object 5 is different, the welding force is different from that of each welded object. There was a drawback that welding could not be performed accurately and stably depending on the type of material 6 or 6.

Therefore, in order to weld two adjacent objects to be welded 6, 6, one object to be welded 6 is first welded to the welding object 5, and then the welded object 6 is moved to a position where it does not touch the upper electrode 1'. Either the welding body 5 is moved and arranged to weld another workpiece 6 to the welding body 5, or another electrode is provided and each welding workpiece 6, 6 is welded.
had to be welded at the same time.

In view of the above-mentioned points, an object of the present invention is to provide an electrode structure for an electric welding machine that does not require moving the welding object and can weld adjacent objects to be welded with one electrode.

The present invention will be explained in detail with reference to the drawings.

FIG. 2 shows an embodiment of the invention.

This lower electrode 4 is used for electric welding, and has a flat electrode surface 2a on its upper surface.

1 is an upper electrode corresponding to the lower electrode 4, and an L-shaped step 3 is formed on one side of a flat electrode surface 2 on the lower surface of the upper electrode 1.

Further, the depth of the step 3 (that is, the distance between the electrode surface 2 of the upper electrode 1 and the horizontal surface 3a of the step 3) is the same as that of the welding body 5 and the workpiece 6.
The height is set to be shallower by a predetermined value A than the stacked height of the two.

The operating state of the electrodes 1 and 4 of the present invention constructed as described above is shown in FIG. 3a=f.

First, as shown in Figure a, the welded object 5 is placed on the electrode surface 2a of the lower electrode 4, and the object to be welded 6, such as a nut, is placed on the upper surface of the welded object 5 under the step 3 of the upper electrode 1. do.

Then, the upper electrode 1 is lowered as shown in FIG. Electricity is applied between electrodes 1 and 4.

At that time, the electrode surface 2 of the upper electrode 1 and the electrode surface 2 of the lower electrode 4
A gap of the predetermined value A is created between the workpiece 6 and the workpiece 6, so that all the current flows through the workpiece 6 and the workpiece 6 is stably welded to the welding body 5.

Next, raise the upper electrode 1 as shown in c and d of the same figure, insert another workpiece 6 onto the upper surface of the welding body 5 below the electrode surface 2 of the upper electrode 1, and place the upper electrode 1 as shown in e of the same figure. Electricity is applied by contacting the electrode surface 2 with the top surface of another workpiece 6, but at this time, there is also a gap between the horizontal surface 3a of the stepped portion 3 and the top surface of the workpiece 6 that has already been welded, so that all of the current flows. The flow passes through another workpiece 6 and the other workpiece 6 is stably bonded.

Next, the upper electrode 1 is raised as shown in FIG. 5F to complete the welding.

Thus, in the present invention, an L-shaped step is provided on one side of the electrode surface of the upper electrode, and the depth of the step is set to be shallower by a predetermined value than the height of the welding body and the workpiece. First, the workpiece is welded to the welding body by holding the workpiece at the step, and then the upper electrode is raised and another workpiece is inserted between the electrode surface of the upper electrode and the electrode surface of the lower electrode. Since the objects to be welded can be welded to the object to be welded, it is possible to stably weld adjacent objects to be welded with exactly the same welding force using one electrode without having to move the objects to be welded. It has the advantage of

[Brief explanation of drawings]

FIG. 1 is a sectional view of a conventional example (not shown), FIG. 2 is a sectional view of an embodiment of the present invention, and FIG. Electrode surface, 3 is step part, 4
is a lower electrode, 5 is a welding body, 6 is a welded object, and A is a predetermined value.

Claims (1)

[Claims] 1 An L-shaped step is provided on one side of the electrode surface on the lower surface of the upper electrode,
An electric welding machine characterized in that the depth of the stepped portion is set to be shallower by a predetermined value than the height of the welding body placed on the upper surface of the lower electrode and the welding object to be electrically welded to the welding body. Electrode structure.