JPS639916B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a resistance welding jig suitable for simultaneously resistance welding a plurality of other objects to be welded to the inner wall of a cylindrical object having a circular or polygonal cross section.

When resistance welding a plurality of second objects to be welded to the inner wall of a cylindrical first object to be welded, conventionally, a first electrode disposed in a cavity of the first object to be welded; The second electrodes are sequentially resistance welded one by one to predetermined locations on the inner wall of the first workpiece using a second electrode disposed on the outside of the workpiece. In such resistance welding, once one second workpiece is welded to a predetermined position on the inner wall of the first workpiece, the next welding position is between the first and second electrodes. The first object to be welded is rotated by a predetermined angle so that the first object to be welded is rotated by a predetermined angle, and then the second object to be welded is placed at the welding position and welded. Repeat an equal number of times. Therefore, it goes without saying that welding takes a very long time, but also requires a complicated driving device to drive the first workpiece according to the welding position, and especially when the first workpiece is cylindrical. In the case where the welding material is shaped like a welding material, there is a drawback that the roundness and cylindricity of the first welded object are reduced due to the pressure applied during each welding process.

The present invention provides a resistance welding jig that can eliminate all of the conventional drawbacks as described above.

An embodiment of the present invention will be described below with reference to FIGS. 1A and 1B.

In FIG. 1, reference numeral 1 denotes a first electrode having a tapered part 1a with a part shaped like a truncated cone, and 2 a hollow space having a diameter slightly larger than the outer diameter of a cylindrical first workpiece 3. second electrodes, 4a to 4f;
5a to 5f are substantially equal parts having tapered surfaces 5a 1 to 5f ₁ that can be compatible with the tapered part _1a of the first electrode 1, respectively. It is an auxiliary electrode divided into 6 parts,
6a to 6g are for second welded objects, which are based on the annular portion 6g and are provided with positioning parts 6a to 6f, which are formed by cutting out portions corresponding to the second welded objects 4a to 4f from an insulating cylinder. , 7 is a support member fixed to the tip of the tapered part of the first electrode 1 with a screw 8 to support the auxiliary electrodes 5a to 5f, and 9 is a support member for each of the auxiliary electrodes 5a to 5f. A small recess 5 provided in a part of the outer side
a ₂ ,...5d ₂ ... is a ring arranged within...
Here, the support member 7, the screw 8 and the ring 9 are connected to the first
A locking mechanism is configured to lock six auxiliary electrodes 5a to 5f to the electrode 1.

Next, the resistance welding jig according to the present invention will be explained in more detail while explaining an example of a resistance welding method.

First, the cylindrical first workpiece 3 is placed in the recess of the second electrode 2 . The cross section perpendicular to the central axis X of the recess of the second electrode 2 is similar to the corresponding cross section of the cylindrical first workpiece 3, and the outer wall of the first workpiece 3 is similar to the second workpiece 3. It is in almost uniform contact with the recess wall of the electrode 2. Next, a positioning member 6 for the second objects 4a to 4f is inserted along the inner wall surface of the cylindrical first object 3 to be welded. The radial thickness of each of the positioning members 6a to 6f made of an electrically insulating material is comparable to or thinner than the radial thickness of the second welded objects 4a to 4f. Next, the second workpiece 4a is placed in the gap between the adjacent positioning members 6a to 6f.
~4f is stored, and then the first electrode 1 positioned above the second electrode 2 is lowered along the central axis X. At this time, the 6
The auxiliary electrodes 5a to 5f also fall. When the six auxiliary electrodes 5a to 5f are in close contact with each other, the outer diameter of the auxiliary electrodes is smaller than the inner diameter defined by the second objects to be welded 4a to 4f.

When the first electrode 1 further descends, the six auxiliary electrodes 5a to 5f stop and are supported at the position where they contact the base portion 6g of the positioning member, but the first electrode 1 is Descend to the position shown. In this way, after the six auxiliary electrodes 5a to 5f stop, in the process of the first electrode 1 descending to the illustrated position, the tapered portion 1a of the first electrode 1 and each of the auxiliary electrodes 5a to 5f are tapered. Due to the effects of the surfaces 5a ₁ ,...5d ₁ ,..., the first electrode 1 is connected to each of the auxiliary electrodes 5a to 5f.
A pressing force is applied in the radial direction to each of the second objects 4a to 4f through. In this case, since the auxiliary electrode is divided into the same number of parts as the second workpieces 4a to 4f, if the thicknesses of the second workpieces 4a to 4f in the radial direction are equal, the second workpieces 4a to 4f have the same thickness. The radial pressing forces applied to the electrodes 4f and 4f are approximately equal, and by passing the welding current between the first electrode 1 and the second electrode 2 in this state, a good welding result can be obtained.

In the above embodiment, the case where the first workpiece 3 is cylindrical has been described, but even if the first workpiece 3 is polygonal, it is sufficient to simply make the recess of the second electrode 2 into a similar polygonal shape. Even if the object to be welded 3 has a bottom, welding can be performed in the same manner as described above by only making slight changes to the locking mechanism and the like. Further, the angle θ of the tapered surface formed by the tapered portion 1a of the first electrode 1 and the auxiliary electrodes 5a to 5f is set to an extent that allows the frictional force with the auxiliary electrode when the first electrode 1 starts to rise. It is sufficient if it is larger than the angle that gives the value of.

Further, in the above embodiment, the second objects to be welded 4a to 4
Although the same number of auxiliary electrodes 5a to 5f as f was used,
The auxiliary electrode may be divided into a plurality of parts, and the number of second objects to be welded may be any number.

As described above, according to the present invention, a first electrode having at least a tapered portion, a plurality of auxiliary electrodes each having a tapered surface capable of engaging with the tapered portion of this electrode, and a cylindrical first electrode are provided. and a second electrode disposed on the outer wall side of the object to be welded, and by inserting the first electrode from the tapered part side substantially along the central axis of the cylindrical first object to be welded. Since resistance welding is performed by applying pressure to each of the second objects through the auxiliary electrode, a desired number of second objects to be welded are simultaneously applied to the inner wall of the cylindrical first electrode. Since it is possible to weld and to apply substantially the same pressure to all the second objects to be welded, substantially equal welding results can be obtained, which is extremely effective in practice.

[Brief explanation of the drawing]

1A and 1B are views showing an embodiment of the welding jig according to the present invention, in which A shows a top view and B shows a sectional view taken along line Y-Y' in the top view. show. 1... First electrode, 2... Second electrode, 3... Cylindrical first welded object, 4a to 4f... Second welded object,
5a to 5f...Auxiliary electrode, 6a to 6g...Positioning member, 7...Supporting member, 8...Screw, 9...Ring.

Claims (1)

[Scope of Claims] 1. An apparatus for resistance welding a plurality of second objects to be welded to the inner wall of a cylindrical first object, comprising: a first electrode having a tapered portion; A plurality of auxiliary electrodes each having a tapered surface that can be combined with each other, and a second electrode disposed on the outer wall side of the first workpiece, the first electrode being connected to the cylindrical part from the tapered part side. A resistance welding treatment characterized in that the plurality of second objects to be welded are subjected to resistance welding by being inserted along substantially the central axis of the first object to be welded, thereby applying pressure to the plurality of second objects to be welded through the auxiliary electrode. Ingredients. 2. In an apparatus for resistance welding a plurality of second objects to be welded to the inner wall of a cylindrical first object to be welded, a first electrode having a tapered part, a tapered part capable of engaging with the tapered part of the electrode is provided. an auxiliary electrode having said first
a second electrode disposed on the outer wall side of the object to be welded; and a locking mechanism capable of locking the plurality of auxiliary electrodes to the first electrode; By inserting the cylindrical first workpiece substantially along the central axis from the side,
A resistance welding jig, characterized in that resistance welding is performed by applying pressure to the plurality of second objects to be welded via the auxiliary electrode.