JPH11179555A - Multiple spot welding method and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate setting of welding conditions and to automate the operation by pressurizing a workpiece with a pressurizing means installed in each welding gun, providing a movable power feeding means that feeds electricity to the welding guns through at least one power feeding circuit to which plural welding guns are connected, and also providing a fixing means that electrically connects the power feeding means to the power feeding route. SOLUTION: A workpiece is placed in a workpiece receiving jig 2, with welding guns 4 arranged near a welding spot. Then, the workpiece is held and pressurized with the electrodes of each welding gun 4 by operating valves. A hand welding gun 8 is fixed on a fixing device 7, clamping a power feeding plate 6 with the electrodes of the gun 8. By operating a control panel 11 and energizing the hand welding gun 8, power is supplied to each welding gun 4 through the power feeding plate 6, bus bar 3 and cable 5, so that a welding operation is performed. A welding operation is also possible by the hand welding gun 8; an operator's omission in spot welding is prevented by fixedly installing the power feeding means.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multipoint welding method for performing a welding operation on an object to be welded, such as an automobile body panel, which is to be welded at a plurality of locations during assembly.

[0002]

2. Description of the Related Art At present, spot welding is frequently used in assembling a body panel of an automobile, but when welding a plurality of locations at the same time, an object to be welded is placed on a workpiece receiving jig. And a plurality of welding guns are arranged around it. Next, the work to be welded is sandwiched between the electrodes of these welding guns, and current is applied while pressurizing the work to be welded with the electrodes, so that welding operations are performed simultaneously or continuously at the respective welding locations.

FIG. 3 shows an example of such a welding apparatus. An apparatus 18 shown in FIG. 3A has a plurality of welding guns 20 arranged on a jig 19 for receiving an object to be welded, and a bus bar 21 for supplying electric power to the welding gun 20 is provided for each welding gun. One end of 21 is connected to the cable 22 of the welding gun 20, and the other end is connected to the power supply plate 23. Pressurization of the workpiece by the welding gun 20 is performed by a pneumatic circuit (not shown) operated by the operation panel 25, and all the welding guns are simultaneously pressurized. Power is supplied to each welding gun 20 from a power supply plate 23. In this apparatus, automatic welding by the welding gun 20 and manual welding by a manual welding gun 24 for performing welding by an operator's own hand are performed in parallel, and welding is performed to the welding gun 20 at the time of automatic welding. The electric power is supplied using a hand-held welding gun 24. That is, the operator sandwiches the power supply plate 23 between the electrodes of the manual welding gun 20 and then operates the manual welding gun 24 to operate the timer 27.
The power is supplied to the welding gun 20 connected to the power supply plate 23 by supplying power to the hand-held welding gun 24 from the transformer 26 having the above-mentioned structure, and the welding operation is performed.

On the other hand, an apparatus 28 shown in FIG. 3B has a plurality of welding guns with one bus bar 30 provided on a jig 29 for receiving an object to be welded.
The bus bar 30 and each welding gun 31 are connected to each other by a cable 32. Pressurization by each welding gun is performed individually by providing an air pressure circuit (not shown) operated by the operation panel 35 for each welding gun.
Electric power is supplied to the welding gun 31 from a transformer 33 having a timer 34, and a welding operation is performed by an operator operating an operation panel 35.

However, in the former device, the welding point,
That is, the bus bar 21 and the power supply plate are provided for each welding gun 20.
Since 23 is required, the number of work steps increases, and if the number of hit points increases, the worker may forget to hit. Furthermore, when performing the welding operation using the manual welding gun 24 in parallel, there is a problem that the setting of the welding conditions such as the current value in the operation using the welding gun 20, that is, the setting of the conditions for adjusting to the manual welding is complicated. . On the other hand, although the latter device has the advantage that all welding operations can be automated, a valve for pressurizing each welding gun 31 is required in the air pressure circuit, and Since the transformer 33 for supplying power needs to have a large output, there is a problem that the cost is higher than the former.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems and to propose a multi-point welding method capable of simultaneously performing welding at a plurality of locations at a relatively low cost. It is in.

[0007]

The method according to the present invention is a multi-point welding method for performing welding at a plurality of locations on a workpiece fixed on a jig by using a plurality of welding guns. In a welding method in which two or more of the welding guns are connected to one power supply path, a step of pressing the workpiece by the plurality of welding guns for each of the welding guns, and supplying power to each of the welding guns. Fixing the movable power supply means at a predetermined position electrically connected to the power supply path, and supplying power to each of the welding guns via the power supply path by the power supply means. Things.

According to the method of the present invention, a common power supply path is provided for a plurality of welding guns, and power is simultaneously supplied to each welding gun through the power supply path. Therefore, it is easy to set and change the welding conditions. Also, by fixing the power supply means to the welding gun, it is possible to prevent forgetting to strike.

Further, according to the present invention, it is not necessary to provide a power supply path for each welding gun, and the operation can be automated, thereby reducing the operation cost.

[0010] The present invention also relates to a multi-point welding apparatus for realizing the above-described method.

An apparatus according to the present invention is a multi-point welding apparatus for performing welding at a plurality of locations on a workpiece fixed on a jig by using a plurality of welding guns. Pressurizing means provided on each of the welding guns,
A plurality of the welding guns are connected, at least one power supply path, and power is supplied to the welding gun through the power supply path,
It comprises movable power supply means and fixing means for fixing the power supply means at a predetermined position electrically connected to the power supply path.

That is, the present apparatus provides a common power supply path (bus bar and power supply plate) for a plurality of welding guns, and supplies power to these welding guns simultaneously. Therefore, setting of welding conditions and the like become easy, and automation of work can be realized. Further, by fixing and installing the power supply means, it is possible to prevent the worker from forgetting to strike.

Further, according to the present apparatus, it is not necessary to provide a bus bar and a power supply plate for each welding gun, and a relatively small transformer can be used for supplying electric power to the welding gun. Can be.

Further, in the present apparatus, even when the automatic welding operation by the welding gun and the manual welding by the operator are used in combination, the setting of the welding conditions, in other words, the welding conditions between the automatic welding and the manual welding are used. Is easy to adjust.

Further, in a preferred embodiment of the present invention, a manual welding gun is used as a power supply means for the welding gun. That is, a power supply plate is sandwiched between electrodes of the manual welding gun, and power is supplied from this electrode. Is also good. Therefore, when performing both automatic welding and manual welding,
There is no need to provide any other power supply means.

[0016]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a plan view showing an embodiment of the welding apparatus according to the present invention. In the present apparatus 1, one bus bar 3 and a plurality of welding guns 4 are arranged on a workpiece receiving jig 2, and the bus bar 3 and each welding gun 4 are connected by a cable 5 of each welding gun 4. One end of the bus bar 3 is connected to a power supply plate 6 provided on the periphery of the workpiece receiving jig 2. Above the power supply plate 6, a fixing device 7 for power supply means for the welding gun 4 is provided. In this example, a hand-held welding gun 8 is used as a power supply means, and the hand-held welding gun 8 is connected to a transformer 9 having a timer 10,
Electric power is supplied from the transformer 9 to the manual welding gun 8.
At the time of the welding operation, the hand-held welding gun 8 is fixed to the fixing device 7, the power supply plate 6 is sandwiched between its electrodes, and power is supplied to the welding gun 4 through the power supply plate 6, the bus bar 3 and the cable 5 by energizing the electrodes. . The operation of the welding gun 4 and the hand-operated welding gun 8 is performed by an operator on the operation panel 11.
Is performed by operating. A valve (not shown) is provided for each welding gun 4 in order to press the workpiece by the welding gun 4.

FIG. 2 is a side view showing a state where the hand-held welding gun 8 is fixed to the fixing device 7 described above. Fixing device 7
Are the columns 12 mounted on the base of the receiving jig 2
And a table 13 provided on the column 12 for fixing the hand-held welding gun 8. The manual welding gun 8 is fixed to the fixing device 7 by fitting the positioning pins 15 provided on the mounting table 13 into the positioning holes 14 provided in the projecting portions 8a on both side surfaces thereof. The strut 12 has a hand-held welding gun 8 attached to the fixing device 7.
When the is fixed, a sensor 16 that comes into contact with the sensor and a limit switch 17 connected to the sensor are provided. The limit switch 16 allows the hand-held welding gun 8
Is detected whether or not is fixed. As shown, the hand-held welding gun 8 has electrodes 8b above and below the power supply plate 6.
And 8c are fixed in place.

Next, the welding operation by the present apparatus 1 will be described. First, the work to be welded is set on the work receiving jig 2,
Each welding gun 4 is disposed near a predetermined welding. Next, the valves (not shown) corresponding to the respective welding guns are operated, and the workpiece is sandwiched between the electrodes of the respective welding guns 4 and pressurized. Further FIG.
As shown in the figure, the hand-held welding gun 8 is fixed to the fixing device 7,
The power supply plate 6 is sandwiched between the electrodes 8b and 8c of the manual welding gun 8. Thereafter, the operation panel 11 is operated to energize the hand-held welding gun 8, thereby supplying power to each welding gun 4 and performing a welding operation. Prior to or after the work, it is also possible to perform a welding work with the hand-held welding gun 8.

The present invention is not limited to the above-described example. For example, when a plurality of bus bars 3 are provided, a fixing device 7 may be provided for each bus bar. Welding gun 8 for power supply
Other means, for example, a welding robot may be used.

[Brief description of the drawings]

FIG. 1 is a plan view of a multipoint welding apparatus according to an embodiment of the present invention.

FIG. 2 is a side view of the device shown in FIG. 1 showing a hand-held welding gun fixing device.

FIG. 3 is a plan view showing a conventional multipoint welding apparatus.

[Explanation of symbols]

 1,18,28 Multi-point welding device 2,19,29 Jig for receiving workpiece 3,21,30 Busbar 4,20,31 Welding gun 5,22,32 Cable 6,23 Power supply plate 7 Power supply means fixing device 8 , 24 Hand-operated welding gun 9, 26, 33 Transformer 10, 27, 34 Timer 11, 25, 35 Operation panel 12 Prop of fixing device 7 Hand-operated welding gun holder 14 Positioning hole for fixing hand-operated welding gun 15 For hand-operated welding gun fixing Positioning pin 16 Sensor 17 Limit switch

Continued on the front page (51) Int.Cl. ⁶ Identification code FI B23K 11/28 B23K 11/28

Claims (3)

[Claims] 1. A multi-point welding method for performing welding at a plurality of locations on a workpiece to be welded fixed on a jig by using a plurality of welding guns, wherein two or more welding guns are connected to one power supply path. In the above welding method, a step of pressurizing the workpiece by the plurality of welding guns for each of the welding guns; and a movable feeding means for feeding power to each of the welding guns; A multipoint welding method, comprising: a step of fixing the welding gun at a predetermined position to be electrically connected; and a step of supplying power to each of the welding guns via the power supply path by the power supply unit. 2. A multipoint welding apparatus (1) for performing welding at a plurality of locations on a workpiece to be fixed on a jig (2) by a plurality of welding guns (4). Pressurizing means provided on each of the welding guns (4) to pressurize the workpiece; at least one power supply path (3) connecting a plurality of the welding guns (4); and the power supply path (3) A movable power supply means (8) for supplying power to each of the welding guns (4) via a power supply, and a fixing means for fixing the power supply means (8) at a predetermined position electrically connected to the power supply path (3). Means (7). 3. The multi-point welding apparatus according to claim 2, wherein said power supply means is a hand-held welding gun.