JPH0357340Y2 - - Google Patents

Description

[Detailed description of the invention] (Industrial application field) The invention involves sandwiching two overlapping metal members between the tips of a pair of electrodes, applying a current to the electrodes to locally heat them, and , In spot welding, where pressure is applied with an electrode to join the welded parts at regular intervals as shown by dotted lines, scratches that occur on metal parts during welding,
This invention relates to a backup body for spot welding used to prevent dents, deformation, etc.

(Prior Art) Conventionally, there has been a backup body for spot welding of this type as shown in FIG. That is, in the drawings, A1 and A2 are a pair of electrodes that are arranged close to and apart from each other. B
1 and B2 are two metal members welded together by the above electrodes A1 and A2, and these metal members B1 and B
2 is pressed into a two-dimensional or three-dimensional shape, such as a curved shape, hemispherical shape, or other shape.

C is a back-up body made of conductive metal, and this back-up body C is arranged between electrodes A1 and A2 insulated from the electrodes A1 and A2, and is shaped like the metal members B1 and B2 to be welded. It is formed to fit.

Therefore, the metal members B1 and B are attached to the backup body C.
After 2 are brought into close contact with each other, this back-up body C and metal members B1, B2 are crimped with electrodes A1, A2, and the two metal members B1, B2 are spot welded by applying electric current. It is.

(Problem to be solved by the invention) However, since the backup body C used in the conventional spot welding as described above is manufactured to match the shape of the metal members B1 and B2 to be welded, a plurality of backup bodies C are used. This requires a long manufacturing time and high cost.Also, during welding, the metal members B1 and B2 must be brought into close contact with the back-up body C, which takes time. , the metal members B1 and B to be welded are
If the shapes of the parts 2 and 2 are different, they must be replaced each time, but the replacement takes a lot of time because of the bolt tightening. Furthermore, since the back-up body C is in close contact with the metal members B1 and B2, welding is always performed at a certain location, so the curved portions of the back-up body C are subject to severe wear, and the entire back-up body C must be made thick. There were some initial shortcomings, such as:

The present invention solves the above-mentioned drawbacks by configuring the backup body as a free flow type.

(Means for Solving the Problems) The present invention includes a pair of spot electrodes arranged close to and apart from each other, a storage groove arranged between the spot electrodes, and a through groove opening from the storage groove to the back surface. The electric conductor block is movably and removably housed in the housing groove and has a smooth upper surface on which the metal member comes into contact.

(Operation of the invention) Therefore, the metal member to be welded is brought into contact with the top surface of the conductor block, one spot electrode is brought into contact with the part of the metal member to be welded, and the other spot electrode is inserted into the through groove from the bottom surface of the mounting bracket. When it is inserted into the conductor block and comes into contact with the lower surface of the conductor block, the conductor block moves and only the part to be welded comes into close contact.

Therefore, by applying a current to both conductor blocks and applying pressure, the outer portions of the metal members are spot welded.

(Embodiment of the invention) Hereinafter, the invention will be described in detail based on an embodiment shown in the drawings.

Fig. 1 is a side view showing the main parts of a spot welding machine to which the back-up body according to the present invention is applied, Fig. 2 is a side view of the same back-up body, and Fig. 3 is a plan view.
4 is a left side view, FIG. 5 is a sectional view taken along the line -- in FIG. 3, and FIGS. 6 and 7 are explanatory views of the operation.

In the above drawings, reference numerals 1 and 2 are a pair of spot electrodes arranged close to and apart from each other.

3 and 4 are two metal members welded together by the spot electrodes 1 and 2, and these metal members 3 and 4 have a predetermined two-dimensional or three-dimensional shape, such as a curved shape, a hemispherical shape, etc. It is pressed into the shape of

Reference numeral 5 denotes a back-up body, which is placed between the spot electrodes 1 and 2 to be insulated from the spot electrodes 1 and 2, and includes two long and short electric conductor blocks 6 and 7.
and a mounting bracket 8 that holds the electrical conductors 6 and 7.
It is composed of. Each of the conductor blocks 6 and 7 has a rectangular parallelepiped shape with flat upper surfaces 6a and 7a, and flanges on both sides.
9a, 9b and 10a, 10b are formed along the longitudinal direction.

On the other hand, the mounting bracket 8 has a rectangular parallelepiped shape that is slightly longer than the length of the two conductor blocks 6 and 7 connected together, and its upper surface is formed into a long slope 11 and a short slope 12 facing toward the valley 8a from both ends. . In the center of both the slopes 11 and 12, a storage groove 13 in which the conductor blocks 6 and 7 are placed is provided.
Storage groove 13 of long slope 11 formed parallel to 2
A long conductor block 6 is stored in the storage groove 13 of the short slope 12, and a short conductor block 7 is stored in the storage groove 13 of the short slope 12, respectively. Further, a through groove 14 is formed in the center of the bottom surface of the storage groove 13 and opens to the lower surface of the mounting bracket 8. Here, it is necessary that the upper surfaces 6a, 7a of both the electric conductor blocks 6, 7 housed in the housing groove 13 both protrude from the slopes 11, 12.

15a, 15b, 16a, 16b are slopes 11,
12, the fall prevention plates 15a, 15b, 16a, 16
b is for preventing the conductor blocks 6, 7 from accidentally popping out from the storage groove 13. In addition, in the storage groove 13, the conductor blocks 6,
7 can freely move up and down and back and forth.
Flanges 9a, 9b, 10 of conductor blocks 6, 7
a, 10b and fall prevention plates 15a, 15
b, 16a, and 16b, it is necessary to form a spaced part of, for example, about 5 mm.

A fixing bracket 17 is formed at the end of the mounting bracket 8 on the short slope 12 side, and the fixing bracket 17 allows the mounting bracket 8 to be disposed between the pair of spot electrodes 1 and 2.

(Operation of Example) Next, the operation will be explained with reference to FIGS. 6 and 7.

First, the two metal members 3 and 4 to be welded are placed on the upper surfaces 6a and 7a of both electrically conductive blocks 6 and 7. Next, one spot electrode 1 is brought into contact with the part to be welded on the surfaces of the metal members 3 and 4, and the other spot electrode 2 is inserted into the through groove 14 from the bottom surface of the mounting bracket 8, and then the spot electrode 2 is inserted into the through groove 14 from the bottom surface of the mounting bracket 8. When the electric conductor block 6 comes into contact with the electric conductor block 6, the electric conductor block 6 moves and only the parts to be welded are brought into close contact.

Therefore, if a current is applied to both electrodes 1 and 2 as in the conventional case, the outer portions of the two metal members 3 and 4 are spot welded.

Since the conductor blocks 6 and 7 are simply stored in the storage groove 13 in a floating state, the conductor blocks 6 and 7 can be easily replaced by taking them in and out from the opening in the longitudinal direction of the storage groove 13. can be done.

(Other Embodiments) In the above embodiment, the conductor blocks 6 and 7 are
The mounting bracket 8 has two slopes 11 and 12.
Although the conductor blocks 6 and 7 and the slope 1 of the mounting bracket 8 are
Of course, one or more number 1 and 12 may be formed.

(Effects of the invention) As described above, the present invention includes a pair of spot electrodes 1 and 2 arranged close to and apart from each other, a storage groove 13 arranged between the spot electrodes 1 and 2, and a storage groove arranged between the spot electrodes 1 and 2. A through groove 14 opening from 13 to the back surface
a mounting bracket 8 having a
The electric conductor blocks 6 and 7 are movably and removably housed in the electric conductor block and have smooth upper surfaces 6a and 7a on which the metal members 3 and 4 come into contact.

Therefore, since the conductor blocks 6, 7 are freely movable relative to the mounting bracket 8, welding is not always performed at one location, so local wear is spread out, and the wall thickness of the conductor blocks 6, 7 is reduced. Materials can be reduced. In addition, since the conductor blocks 6 and 7 do not need to be manufactured to match the shape of the metal members 3 and 4 to be welded, the manufacturing time is shortened.
Unlike the conventional structure, there is no need for a plurality of conductor blocks 6, 7, and since the conductor blocks 6, 7 are simply accommodated in the storage groove 13 in a loose state, the longitudinal direction of the storage groove 13 is By putting in and taking out the parts through the opening, replacement work can be done easily and in a short time, and costs can also be reduced. Furthermore, during welding, the metal members 3 and 3 are attached to the conductor blocks 6 and 7.
Since there is no need to align the parts 4 and 4, the setting work does not take much time.

[Brief explanation of the drawing]

Fig. 1 is a side view showing the main parts of a spot welding machine to which the back-up body according to the present invention is applied, Fig. 2 is a side view of the same back-up body, Fig. 3 is a plan view, and Fig. 4 is a left side view. FIG. 5 is a sectional view taken along the line -- in FIG. 3, FIGS. 6 and 7 are explanatory views of the operation, and FIG. 8 is a side view showing the main parts of a spot welding machine to which a conventional backup body is applied. 1, 2...Spot electrode, 3,4...Metal member, 5...Backup body, 6,7...Conductor block, 6a, 7a...Top surface, 8...Mounting bracket, 13...Storage groove, 14...through groove.

Claims (1)

[Scope of utility model registration request] A mounting bracket is disposed between a pair of spot electrodes that can be freely approached and separated, and has a storage groove and a through groove that opens from the storage groove to the back surface; 1. A back-up body for spot welding, comprising a conductor block having a smooth upper surface that comes into contact with a member.