JPS6110859Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to an improvement of a spot welding device.

Conventionally, spot welding equipment for welding floor panels to automobiles, for example, includes a lower arm on which a fixed electrode is attached, and an upper arm on which an upper electrode facing the fixed electrode is attached, on a truck.
Both electrodes are connected to a welding transformer installed on the floor via a power supply cable, and by moving the trolley, both electrodes are moved to the appropriate location on the floor panel of the car, and by swinging the upper and lower arms, the floor panel is moved by both electrodes. Spot welding devices have been put into practical use.

However, since the trolley moves, it requires a long power supply cable to match the movement stroke, and there is a problem that durability deteriorates due to repeated bending.
When there is a convex portion on the peripheral edge, there is a problem in that the upper and lower arms have to be opened wide, resulting in a large movement loss.

This idea was made in view of the above-mentioned conventional problems. An arm with an upper electrode attached thereto is supported in a vertically movable manner on a table that is movable back and forth on the base, and the object to be welded in front of the base is A plurality of fixed electrodes are protruded at predetermined intervals at the welding position to enable spot welding with only minimal swinging of the arm.
A current collector for connecting the welding transformer and the upper electrode at the device fixing site is arranged between the device fixing site and the table, thereby eliminating the need for a long moving power supply cable.

Hereinafter, embodiments of this invention will be described in detail with reference to the accompanying drawings.

As shown in the figure, the spot welding equipment
A table 3 is placed on a base 2 placed on the right side in the above figure, and is guided by the base 2 so as to be movable back and forth, while fixed pulleys 4, 4 are installed at the front and rear ends of the base 2, respectively. At the same time, movable pulleys 8, 8 are respectively fixed to the piston rods 7, 7 of the piston 6 of the double-acting cylinder 5 disposed inside the base 2, and fixed pulleys 4, 4, movable pulley 8,
Chains 9 and 9 are respectively fixed to brackets 10 and 10 of the floor plate 1 via 8, and the table 3 is moved back and forth by the reciprocating movement of the cylinder 5.

A stand 11 is erected on the table 3, and an arm 12 that extends forward and is pivoted to the stand 11 so as to be able to swing up and down on a support shaft 13. 14 is attached, and the lower rear end of the arm 12 is connected to a piston rod 17 of a piston 16 of a cylinder 15 mounted on the table 3, so that the arm 12 can be swung up and down by the operation of the cylinder 15.

A plurality of fixed electrodes 20, .
0 are provided to protrude at predetermined intervals in the front-rear direction.

On the other hand, a welding transformer 21 is installed on the floor plate 1 between the bases 2 and 18, and the transformer 4 and the fixed electrode 20 are connected with a power supply cable 22.

On the table 3, a relay electrode holder 24 in which relay electrodes 23, . At the same time, there is a table 3 on the floor plate 1.
The contact cylinder 27 supporting the contact electrode 26 in contact with one of the relay electrodes 23 is fixed at the moving position, and the contact electrode 26 and the slance 21 are connected by a power supply cable 28.

The contact cylinder 27, the contact electrode 26, the relay electrode 23, and the relay electrode holder 24 constitute a current collector.

If the spot welding equipment is configured as described above,
The object to be welded 19 is placed on the fixed electrodes 20 and set at the welding position corresponding to each fixed electrode 20, and then the table 3, which has been moved to the retreat position shown by the two-dot chain line in the figure, is moved by the actuation of the cylinder 5. to move the upper electrode 14 of the arm 12 forward to the nearest stationary electrode 2.
0, the operation of the cylinder 5 is stopped by turning on the limit switch, and the table 3
to stop at the relevant position.

Thereafter, the cylinder 27 is actuated to bring the contact electrode 26 into contact with the relay electrode 23 of the relay electrode holder 24, and the cylinder 15 is actuated to bring the contact electrode 26 into contact with the relay electrode 23 of the relay electrode holder 24.
When the upper electrode 14 is brought into contact with the fixed electrode 20 with the workpiece 19 in between, the upper electrode 1
A workpiece 19 is spot-welded between the fixed electrode 20 and the fixed electrode 20 .

Next, the cylinder 15 is operated to swing the arm 12 upward, and the cylinder 27 is operated to separate the contact electrode 26 from the relay electrode 23, and then the cylinder 5
The table 3 is moved forward by the operation, and at a position where the upper electrode 14 of the arm 12 faces the next fixed electrode 20, the limit switch is turned on to stop the operation of the cylinder 5 and stop the table 3 at that position.

Then, while repeating the spot welding operation according to the above-described procedure, the welding positions corresponding to the fixed electrodes 20, . . . , 20 are successively spot welded.

In the above spot welding work, the workpiece 19
Even if there is a protrusion 19a, the lower electrode 20 is fixed and only the upper electrode 14 swings on the arm 12, so there is no need to swing the arm 12 avoiding the protrusion 19a. There is no need to set it large.

In the above embodiment, the table 3 is moved by the cylinder 5, but it may be moved by a screw feeding mechanism. Moreover, since each of the fixed electrodes 20, .

As is clear from the above explanation, this invention uses the upper electrode of the swinging arm on the movable table to
Since it is moved to a position opposite to the protruding fixed electrode corresponding to the welding position of the workpiece, there is no need for a conventional lower arm, and it can be used even on workpieces with convex parts. Only by swinging the upper arm, spot welding can be performed quickly without movement loss.

In addition, since the current collector for connecting the welding transformer and the upper electrode is placed between the device fixing part and the table, there is no need for a long power supply cable, and there is no need for repeated bending, resulting in increased durability. You will start to improve.

[Brief explanation of the drawing]

The figure is a front view of the spot welding device. 2... Base, 3... Table, 5, 15, 27
... Cylinder, 12 ... Arm, 14 ... Upper electrode, 19 ... Welded object, 20 ... Fixed electrode, 21
... Welding transformer, 22, 25, 28 ... Cable, 23 ... Relay electrode, 24 ... Relay electrode holder, 26 ... Contact electrode.

Claims (1)

[Scope of utility model registration request] A table is supported on a base so as to be movable back and forth, and an arm with an upper electrode attached to the bottom of the tip is supported on the table so as to be swingable up and down, and in front of the base, it corresponds to the welding position of the object to be welded. A plurality of fixed electrodes are made to protrude at predetermined intervals in the front-rear direction, while a moving drive device is provided on each of the table and arm, and a current collector is provided for connecting the welding transformer at the device fixed portion and the upper electrode. A spot welding device characterized in that the device is disposed between a device fixing part and a table, and welding is performed by moving an upper electrode to a position facing the fixed electrode.