JPH01162580A - Automatic welding equipment - Google Patents

Abstract

PURPOSE:To improve welding efficiency by arranging a swing arm and a transferring arm in order to a welding equipment main body and fitting a back electrode, a contact electrode and a welding chip electrode to the swing arm and the transferring arm respectively. CONSTITUTION:The swing arm 13 is set up on the welding equipment main body 4 and made turnable round a pin 14 via a cylinder 12. The back electrode 15, a transferring cylinder 18 and the transferring arm 19 are arranged to the upper part of the arm 13 and an electrode arm 22 is provided to the front end of the arm 19 and the feeding contact electrode 23 and the welding chip electrode 24 are arranged thereto. The arms 13 and 19 are turned by the cylinders 12 and 18 respectively and the electrode arm 22 is arranged to the position not to interfere with a work 5 and the arm 13 and the arm 19 are then held vertically and horizontally respectively and the respective electrodes are energized and welding is performed in cooperation with a welding gun 8. Since a wrist action of a robot is reduced, the welding efficiency is improved.

Description

[Detailed description of the invention] a. Industrial application field The present invention relates to automatic welding equipment.

b. Conventional technology Conventionally, for example, welding of the underbody of a four-wheeled vehicle was performed using the fourth method.
This was done using the automatic welding equipment shown in the figure. This device includes a transport means (not shown) on which a workpiece 51 such as an underbody is placed and transported, and a welding robot 52 arranged in relation to this transport means.

The welding robot 52 has an arm 53 that can be freely controlled three-dimensionally, and a welding gun 54 is attached to the tip of the arm 53. Then, when the workpiece 51 is transported by the transport means to a predetermined position in front of the welding robot 52,
The welding robot 52 is configured to start operating and perform a predetermined welding process.

C0 Problems to be Solved by the Invention However, in the conventional automatic welding device described above, electricity is supplied while the tip of the welding gun 54 attached to the arm 53 is in contact with the surface to be welded of the workpiece 51. Since spot welding is carried out using a single workpiece 51, the welding robot 52 has to make many wrist movements when the directions of the surfaces to be welded are significantly different, which increases the size and total time of the welding operation.

Therefore, in addition to the welding robot 52, the conventional automatic welding device is equipped with a multi-spot welding machine 55, and the multi-spot welding machine 55 welds either side of the workpiece 51 to be welded, thereby completing the cycle. We are trying to shorten the time. For example, in FIG. 4, part A of the workpiece 51 is welded by a welding robot 52, and part 8 is welded by a multi-spot welder 55. However, the use of the multi-spot welding machine 55 has many problems, such as increased equipment costs and complicated maintenance management, as well as reduced space within the factory.

The present invention has been made in view of these circumstances, and its purpose is to provide an automatic welding device that can solve the above-mentioned problems.

d. Means for Solving the Problems In order to solve the problems of the above-mentioned prior art, the present invention (a) has an arm movable in a desired direction, and has a welded part at the tip of the arm. a welding robot to which a gun is attached; a device body installed in the movement area of the arm of the welding robot and having a back electrode and a transfer mechanism; a device body that is swingably attached to the transfer mechanism; A contact electrode that is transferred in the vertical direction by the welding gun and is supplied with power under pressure by the welding gun when welding the workpiece, and a welding tip electrode that is arranged opposite to the back electrode and that holds the workpiece between it are different from each other. and an electrode arm provided at the position.

Hereinafter, the present invention will be explained in detail based on illustrated embodiments.

1 to 3 show an embodiment of the present invention, and in the figures, l is an automatic welding device, and this welding device 1 is connected to a welding robot 2 controlled by a control panel (not shown), A device main body 4 and a positioning jig 6 for placing and positioning a workpiece 5, which is an object to be welded, are installed in the moving area of the arm 3 of the welding robot 2, and a lifting device for lifting and lowering the workpiece 5. and a transport device 7, respectively. The welding robot 2 has an arm 3 that is three-dimensionally movable in a desired direction, and a welding gun (stand gun) 8 is attached to the tip of the arm 3.

The device main body 4 includes a base portion 10- to which a bracket 9 having a U-shaped horizontal cross section is fixed to the upper end portion, and a swing whose lower end surface is attached to the base portion 10 via a support stay 11 and a swing cylinder 12. The swing arm 13 is the operating lot 1 of the swing cylinder 12.
The support stay 11 is configured to be able to rotate in the direction of the arrow a about the pivot pin 14 of the support stay 11 by vertical movement of the support stay 2a. The bracket 9 engages with and holds the lower side surface of the swing arm 13 during welding of the workpiece 5, and serves as a stopper that prevents the swing arm 13 from rotating in the counterclockwise direction.

Furthermore, a back electrode 15 and a transfer mechanism 16 are arranged on the upper part of the swing arm 13.

The back electrode 15 is one electrode for holding the workpiece 5, and is attached to the side surface of the swing arm 13 via a fixing member 17. The transfer mechanism 16 includes a transfer cylinder 18 attached to the side opposite to the back electrode 15.
and a transfer arm 19 which is arranged horizontally above the swing arm 13 and whose rear end is connected to the actuating rod 18a of the transfer cylinder 18, and the intermediate portion of the transfer arm 19 is connected and supported by a stay 20. The lower end of the stay 20 is attached to the swing arm 13 by a mounting pin 21, and is configured to rotate around the mounting pin 21. In addition, the transfer arm 19 is
The transfer cylinder 18 is configured to rotate in the direction indicated by the arrow by the vertical movement of the operating loft 18a about the rear end. ' A conductive electrode arm 22 is attached to the front part of the transfer arm 19 so as to be swingable in the direction of arrow C, and the electrode arm 22 has power supply contact electrodes 23 arranged at different positions. A weld cap tip electrode 24 is provided. That is, the contact electrode 23 is arranged so as to be able to face the tip of the welding gun 8, and the tip electrode 24
is arranged so as to be able to face the back electrode 15.

In addition, the attachment part of the electrode arm 22 and the transfer arm 19
A pair of columns 25 and 26 are erected on the upper surface facing each other, and a spring 27 is installed between these columns 25 and 26.
has been erected. Therefore, the electrode arm 22 is constantly pulled toward the rear transfer cylinder 18 side by the spring 27 and urged upward, and the electrode arm 22 is
The structure is such that the tip electrode 24 does not collide with the back electrode 15 when it rotates counterclockwise.

On the other hand, a plurality of guide pins 28 are erected on the upper surface of the positioning jig 6 to guide and hold the workpiece 5 in a predetermined position. The elevating and lowering conveyance device 7 is arranged in relation to the device main body 4 so that it can be moved up and down in the direction of arrow d by a drive means (not shown). It is designed to be placed on a machine or transported to the next process.

To weld the workpiece 5 using the automatic welding device 1, first, the operating rods 12a and 18a of the swing cylinder 12 and the transfer cylinder 18 are operated downward. Along with this, the swing arm 13 and the transfer arm 19 rotate clockwise, and the electrode arm 22
The electrode arm 22 is also rotated clockwise by the biasing force of the spring 27, and the electrode arm 22 is placed in a position where it does not interfere with the workpiece 5.

In this state, as shown in FIG.
At step 7, it is transported to the position of the positioning jig 6, and is lowered to a predetermined position on the jig 6 for positioning.

Next, the swing cylinder 12 and the transfer cylinder 1
When the operating rods 12a and 18a of 8 are operated upward, the swing arm 13 and the transfer arm 19 rotate counterclockwise, and the swing arm 13 engages with the bracket 9 and is held substantially vertically, and the transfer arm 19 is held almost horizontally. Accordingly, the electrode arm 22 rotates counterclockwise by its own weight against the biasing force of the spring 27 and is held at the position shown in FIG. 2. Thus, the part of the workpiece 5 to be welded is arranged between the back electrode 15 and the tip electrode 24.

Thereafter, the welding gun 8 is moved downward (in the direction of the arrow shown in FIG. 2) by the arm 3 of the welding robot 2, and its tip is brought into pressure contact with the contact electrode 23, so that the electrode arm 22
Press down. Then, the electrode arm 22 further rotates toward the swing arm 13 side, and the workpiece 5 is held under pressure by the tip electrode 24 and the back electrode 15 (see FIG. 1). In this state, the contact electrode 2 is
3. If the back electrode 15 is energized through the electrode arm 22 and the tip electrode 24 and a large current is passed for a short time at right angles to the joint surface of the workpiece 5, a nugget is formed on the contact surface, and the workpiece 5
welding is completed. Thereafter, the swing arm 13, the transfer arm 19, and the electrode arm 22 are returned to the state before welding shown in FIG. 3, and the transport device 7 is raised to transport the workpiece 5 from the jig 6 to the next process.

According to the automatic welding device 1 configured in this way, the electrode arm 22, which is swingably attached to the transfer arm 19, is disposed between the welding gun 8 and the back electrode 15, so that the wrist motion of the welding robot 2 can be reduced. At the same time, difficult-to-weld areas can be easily welded. Furthermore, since the pressing force of the welding gun 8 on the electrode arm 22 can be adjusted by the control device, the clamping force between the back electrode 15 and the tip electrode 24 can be changed in accordance with the material, wall thickness, etc. of the workpiece 5. This makes it possible to achieve an optimal welding finish. Furthermore, in addition to the transfer mechanism 16, the swing arm 1
3, there is no interference between the work 5 and the electrode arm 22 when the work 5 is transported.

Although one embodiment of the present invention has been described above, the present invention is not limited to the embodiment described above, and various modifications and changes can be made based on the technical idea of the present invention.

For example, in the previously described embodiment, the contact electrode 23 and the tip electrode 24 provided on the electrode arm 22 are arranged in substantially perpendicular directions, but the angle formed by the picture electrodes 23 and 24 depends on the position of the welded part of the workpiece. Needless to say, various changes can be made depending on the shape.

e. Effects of the Invention As described above, the automatic welding device according to the present invention has an electrode arm swingably attached to the transfer mechanism, and a contact electrode and a back electrode that are pressurized and supplied with power by a welding gun to the electrode arm. Since the welding tip electrodes that hold the workpiece are placed in different positions, it is possible to reduce the wrist movements of the welding robot, significantly shortening the cycle time of welding work and improving work efficiency. I can figure it out. Furthermore, the automatic welding device of the present invention can easily weld workpieces in difficult-to-weld locations where the direction of the welding surface is significantly different without using a multi-welder, reducing equipment costs and saving time in the factory. While it is possible to save space, maintenance and management of the device becomes easy, which is extremely advantageous economically.

[Brief explanation of the drawing]

1 to 3 show an embodiment of the present invention, in which FIG. 1 is a schematic front view of an automatic welding device during welding, and FIG.
FIG. 3 is a schematic front view of the automatic welding device immediately before welding, FIG. 3 is a schematic front view of the automatic welding device during transport of a workpiece, and FIG. 4 is a schematic perspective view of a conventional automatic welding device. ■...Automatic welding equipment, 2...Welding robot,
3...Arm, 4...Device body 5...
・Workpiece, 8... Welding gun, 10...
Base portion, 15... Back electrode, 16...
Transfer mechanism, 18... Transfer cylinder, 19.
...Transfer arm, 22...Electrode arm, 23...
Contact electrode, 24...Welding tip electrode. Patent applicant: Suzuki Motor Co., Ltd. (and 2 others)

Claims (1)

[Scope of Claims] (a) A welding robot having an arm movable in a desired direction and having a welding gun attached to the tip of the arm; (b) installed in the movement area of the arm of the welding robot. (c) a device body that is swingably attached to the transfer mechanism and is transferred vertically by the transfer mechanism, and that is pressurized by the welding gun when welding the workpiece; An automatic welding device comprising: an electrode arm provided with a contact electrode to be supplied with electricity and a welding tip electrode disposed opposite to the back electrode and holding a workpiece between the back electrode and the electrode arm at different positions, respectively; .