JPH0857656A - Welding jig - Google Patents

Abstract

PURPOSE: To make welding at the welding point hard for spot welding possible with a small welding gun. CONSTITUTION: While an electrode tip 54 of a welding gun 52 is pressed on a fixed electrode 42 and an electrode tip 56 is pressed on the upper end of a moving electrode 46, a cylinder rod 58 is extended. By this method, the electrode 56 pushes out the upper end of moving electrode 46, the moving electrode 48 pressurizes a flange part 16A, the flange part 16A and flange part 20A are spot welded. When the spot welding is completed, by retracting the rod 58, the moving electrode 46 is turned in counterclock direction by energizing force of a tension spring 50, the moving electrode 48 is instantly detached from the flange part 16A.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a welding jig used for spot welding.

[0002]

2. Description of the Related Art In an automobile assembly line or the like, spot welding is performed to join panels to each other.

The spot welding is resistance welding performed by sandwiching the stacked panels with the tips of the electrode tips, concentrating the current in a relatively small portion to locally heat the panels, and simultaneously applying pressure to the electrode tips.

The work methods of spot welding are roughly classified into the following three types. As a first method, as shown in FIG. 5, a panel 72 fixed to the workbench 70,
This is a method in which an operator presses the electrode tips 76 and 78 of the large welding gun 74 to the welding point of 73 to perform spot welding. However, this welding gun 74 is heavy, and the work efficiency is poor due to heavy labor. Especially when the welding point is at the back, the panel 72
Spot welding must be done so that
Inconveniences such as poor welding and distortion of the panel have occurred.

As a second method, there is a method of performing spot welding with a dedicated automatic welding machine. With this method, the quality is stable and the work efficiency is improved, but since the equipment cost is high and it is not versatile, some parts cannot be welded depending on the shape of the panel.

A third method is to use a welding robot. Although this method has general versatility, it requires high equipment cost, is complicated in control, and easily causes welding distortion.

Therefore, an auxiliary electrode unit 80 as shown in FIG. 6 has been proposed so that the equipment cost can be suppressed and various panel shapes can be dealt with (Japanese Patent Laid-Open No. 5-19277).
(See Japanese Patent Publication No. 1).

The auxiliary electrode unit 80 includes a support member 8
The arm 84 is rotatably supported by the intermediate portion 2. The tip of the arm 84 has an electrode tip 86.
Is provided and faces the fixed electrode tip 94 of the fixed electrode unit 92 that is grounded to the outer surface of the U-shaped panel 90, and is grounded to the inner surface of the panel 88.

However, since the fixed electrode unit 92 and the auxiliary electrode unit 80 have no structural connection, the rear end side of the arm 84 is sandwiched by the electrode tip 98 of the small welding gun 96 to fix the fixed electrode tip. Accurate positioning of the electrode tip 86 of the auxiliary electrode unit 80 on the inner surface of the panel 88 so as to face the surface 94 requires skill.

[0010]

SUMMARY OF THE INVENTION In consideration of the above facts, the present invention enables welding at a welding point where spot welding is not easy, facilitates positioning of electrode tips, and enables welding with a small welding gun. An object is to provide a welding jig that enables the welding.

[0011]

According to a first aspect of the present invention, there is provided a welding jig, wherein a fixed electrode tip which is set on a workbench and is grounded to a welding point inside a panel, and a fixed electrode tip electrically connected to the fixed electrode tip. A fixed electrode connected to the outside of the panel and located on the welding point side; and a movable electrode that is rotatably rotatably supported by a supporting means that supports the fixed electrode on the worktable and is in a non-conductive state with the fixed electrode. And a movable electrode tip which is disposed on the movable electrode and which can be grounded at a welding point on the outside of the panel where the fixed electrode tip is grounded by the rotation of the movable electrode.

A welding jig according to a second aspect of the present invention is characterized in that a biasing means is provided for biasing the movable electrode in a direction in which the movable electrode tip moves away from a welding point on the outside of the panel.

A welding jig according to a third aspect of the present invention has a retracting means for rotatably supporting the supporting means on the work table and rotating and retracting the fixed electrode and the movable electrode from an upper region of the work table. It is characterized by that.

[0014]

In the welding jig according to the first aspect of the present invention, the panels are stacked and set on the workbench so that the fixed electrode tip is grounded to the welding point inside the panel.

Here, one electrode tip of the small welding gun is grounded to the fixed electrode, and the other electrode tip is grounded to the movable electrode. Here, when the cylinder of the welding gun is driven to extend the electrode tip, the movable electrode rotates, and the movable electrode tip arranged on this movable electrode becomes the welding point outside the panel where the fixed electrode tip is grounded. Ground. Since this fixed electrode tip is electrically connected to the fixed electrode, the inside and outside of the panel are energized and spot welded.

As described above, since the movable electrode tip of the movable electrode is set to correspond to the fixed electrode tip by the rotation of the movable electrode, the worker uses the electrode tip of the welding gun as the fixed electrode. Only by sandwiching the movable electrode, spot welding can be easily performed without positioning.

In the welding jig of the second aspect, the movable electrode is biased by the biasing means in the direction away from the welding point on the outside of the panel. Therefore, unless the movable electrode is sandwiched by the welding gun against the biasing force of the biasing means, the movable electrode tip is not grounded to the panel.

In the welding jig according to the third aspect of the invention, the supporting means for rotatably supporting the movable electrode is rotatably supported on the work table by the retracting means. Thus, when the panel is set on the workbench, the movable electrode can be pivotally retracted, so that the panel can be installed quickly.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in FIGS. 1 and 2, a welding jig 10 according to this embodiment is mounted on a workbench 14 supported by legs 12.

A holder 18 for holding the panel 16 placed in a horizontal state and a holder 22 for holding a panel 20 suspended in a vertical state are provided on the work table 14. Further, the flange portion 16A bent upward from the end portion of the panel 16 and the flange portion 20A bent downward from the upper end of the panel 20 are overlapped so as to form a standing wall, and are fixed by a clamp (not shown). The overlapping portion of the flange portion 16A and the flange portion 20A is the welding point of spot welding.

On the workbench 14, the flange portion 2
A plate-like connecting plate 24 is provided along the width direction of the panel 20 at the 0A side. Fixed electrodes 26 are arranged on the connection plate 24 at regular intervals. A fixed electrode tip 28 is disposed on the upper end of the fixed electrode 26 and is grounded to the flange portion 20A. That is, the fixed electrode tip 28 is under the overhanging panel 20.

On the other hand, from the right corner of the workbench 14, the support plate 30
Is erected. The support member 30 includes a link member 32.
Is rotatably pivotally supported, and a stopper 3 formed on the shaft portion
In No. 1, the rotation range is restricted to about 180 degrees. One end of a small link 34 is pivotally supported near the end of the link member 32, and a bracket 38 extending downward from an L-shaped support block 36 is pivotally supported at the other end of the small link 34. Has been done. A stopper (not shown) is provided on the shaft portion of the small link 34 and the bracket 38, and when the link member 32 rotates back and forth, the support block 36 is erected upright as shown in FIGS. 1 and 2. It is designed to be stopped in a closed state.

A plate-shaped fixed electrode 42 is provided on the back surface of the support block 36 with an insulating plate 41 interposed therebetween. The fixed electrode 42 is connected to the connection plate 24 and the cable 25.
And is electrically connected.

A shaft 44 is stretched between the support blocks 36. A block-shaped movable electrode 46 having a widened central portion is axially supported on the shaft 44 at predetermined intervals. A movable electrode tip 48 is provided at the lower end of the movable electrode 46.
The movable electrode 46 is arranged on the shaft 44 so that the fixed electrode tip 28 provided on the fixed electrode 26 and the fixed electrode 8 face each other.

Further, as shown in FIG. 3, one end of a tension spring 50 is connected to the back surface of the movable electrode 46. The other end of the tension spring 50 is connected to a stop plate 52 arranged in parallel with the shaft 44. As a result, when the tension spring 50 is in the free state, the movable electrode 4 is centered around the shaft 44.
The upper end of 6 is tilted counterclockwise. The rotation range is set so that the upper end of the movable electrode 46 is not grounded to the fixed electrode 42 when the upper end of the movable electrode 46 is pressed clockwise and the movable electrode tip 48 is grounded to the flange portion 16A. .

Next, a welding procedure using the welding jig 10 according to this embodiment will be described. As shown in FIG. 1, first, the link member 32 is tilted backward to retract the movable electrode 46 and the fixed electrode 42 from the upper region of the workbench 14. Next, place the panel 16 horizontally on the holder 18 of the workbench 14,
The panel 20 is suspended from the holder 22 and fixed by a clamp (not shown). At this time, the flange portion 16A and the flange portion 20A are overlapped, and the flange portion 20A is grounded to the fixed electrode tip 28 of the fixed electrode 26. Thus, by retracting the movable electrode 46, the panel installation work can be performed quickly.

Here, when the link member 32 is rotated toward the workbench 14, as shown in FIGS. 2 and 3, the stopper 31 provided on the shaft portion of the support plate 30 causes about 180 degrees.
The support block 36 stops in the upright state by the function of the small link 34. At this time, the movable electrode tip 48 of the movable electrode 46 is moved to the fixed electrode 26.
The fixed electrode tip 28 is faced with a fixed space.

Next, the electrode tip 5 of the small welding gun 52
4 is pressed against the fixed electrode 42, and the electrode tip 56 is pressed against the upper end of the movable electrode 46. Here, the rod 58 of the cylinder having the electrode tip 54 attached to its tip is extended. As a result, as shown in FIG. 4, the electrode tip 56 relatively pushes out the upper end of the movable electrode 46 to the right in the figure, and the movable electrode tip 48 pressurizes the flange portion 16A.
The flange portion 16A and the flange portion 20A are spot-welded.

After the spot welding is completed, the rod 58 is expanded and contracted. As a result, the movable electrode 46 is rotated counterclockwise by the urging force of the tension spring 50, and the movable electrode tip 48 is rotated.
Instantaneously separates from the flange portion 16A.

Although all the welding points are welded by repeating such an operation procedure, it is not necessary to position the electrode tip on the cathode side and the electrode tip on the anode side as in the conventional case, so that the operation is quick. And also improve the quality of welding.

[0031]

Since the present invention has the above-described structure, it is possible to easily perform welding at a welding point where spot welding is not easy with a small welding gun. In addition, since the electrode tips are automatically aligned, the work proceeds quickly and the quality of welding is improved.

[Brief description of drawings]

FIG. 1 is an overall perspective view showing a state in which a movable electrode of a welding jig according to an embodiment is retracted.

FIG. 2 is an overall perspective view showing a state in which a movable electrode of the welding jig according to the present embodiment is set.

FIG. 3 is a side view showing a state before the movable electrode tip of the welding jig according to the present embodiment is grounded to the panel.

FIG. 4 is a side view showing a state in which the movable electrode tip of the welding jig according to the present embodiment is grounded to the panel.

FIG. 5 is a conceptual diagram showing a working state of spot welding with a conventional large welding gun.

FIG. 6 is a side view showing a conventional auxiliary electrode unit.

[Explanation of symbols]

 28 Fixed Electrode Chip 30 Support Plate (Supporting Means) 32 Link Member (Retracting Means) 34 Small Link (Retracting Means) 36 Support Block (Supporting Means) 42 Fixed Electrode 46 Movable Electrode 48 Movable Electrode Chip 50 Tension Spring (Biasing Means)

Claims (3)

[Claims] 1. A fixed electrode tip set on a workbench and grounded to a welding point inside the panel and grounded, and a fixed electrode electrically connected to the fixed electrode tip and located on the welding point side outside the panel. A movable electrode that is rotatably supported by a supporting means that supports the fixed electrode on the workbench and is in a non-conductive state with the fixed electrode; and the movable electrode disposed on the movable electrode is fixed by the rotation of the movable electrode. And a movable electrode tip capable of being grounded at a welding point outside the panel where the electrode tip is grounded. 2. The welding jig according to claim 1, further comprising an urging means for urging the movable electrode tip in a direction in which the movable electrode tip moves away from a welding point outside the panel. 3. The retracting means for rotatably supporting the supporting means on the workbench, and for retracting the fixed electrode and the movable electrode from the upper region of the workbench, respectively. The welding jig according to claim 2.