JPH0698505B2 - Automatic welding electrode shaping and replacement device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an apparatus for automatically shaping and exchanging electrodes provided to a welding robot in a carriage welding line using a robot welding machine.

(Prior Art) Conventionally, in the hitting step of spot welding by a robot, when the electrode is worn and deformed, the electrode is manually shaped with a file or the electrode is removed and collected at one place, It has been practiced to manually attach an electrode that has been subjected to intensive polishing by a drilling machine or the like and that has been shaped to a robot welding gun.

However, recently, a device for automatically shaping or exchanging electrodes by using the automatic electrode shaping machine 1 and the automatic electrode exchanging machine 10 as shown in FIGS.

The electrode shaping machine 1 shown in FIG. 4 has been applied for in Japanese Patent Application No. 60-102379 (unpublished), and the tip of the welding gun 2 provided on a pedestal 7 by a welding robot (not shown). A first clamp arm (first clamp means) 5 for sandwiching the pair of electrodes 3 respectively, a grinding tool 4 which is rotated around a vertical axis by a motor (air motor) 6, and the grinding tool 4 is advanced and retracted in the vertical direction. A moving cylinder (first moving means) 8 is provided. In this electrode shaping machine 1, the electrode 3 of the welding gun 2 which is thrown in by the movement of the welding robot is moved to the first position.
After being clamped by the clamp arm 5, the grinding tool 4 is rotated by the cylinder 8 while the grinding tool 4 is rotated by the motor 6.
Is moved upward or downward, the grinding tool 4 shapes the pair of welding electrodes 3. At this time, since the electrode 3 is held by the first clamp arm 5, it is possible to use a small robot as a robot without applying shaping pressure to the welding robot, and a welding line requiring a large number of robots. Suitable for

On the other hand, since the electrode exchanger 10 shown in FIG. 5 is disclosed in Japanese Utility Model Laid-Open No. 61-41482, the electrode holder 11a of the electrode 11 held by the welding robot (not shown) is attached to the second clamp arm (second (2) clamping means (12) and the tip of which has a wedge shape is inserted into the electrode extraction tool 13 between the electrode 11 and the electrode holder 11a, and the electrode 11 is held by the wedge action.
Remove from 11a, drop into hopper 14 and discharge. The new electrode 15 is supplied from the feeder 16 and placed on the electrode mounting tool 17. The electrode mounting tool 17 is horizontally and vertically moved by the mounting tool cylinders (second moving means) 18 and 19, and operates to mount the new electrode 15 on the electrode holder 11a. According to this electrode exchange machine 10, since the electrode holder 11a is held by the second clamp arm 12, no exchange pressure is applied to the welding robot, and it becomes possible to use a small robot as a robot. It is suitable for welding lines that require a large number of robots.

(Problems to be solved by the invention) However, in the method of manually molding with a file or the method of manually attaching and detaching the electrode, a lot of man-hours are required, and a person must enter and leave the working part of the robot. It is dangerous because it must be done. When using an automatic electrode shaping machine and an automatic exchange machine, one robot automatic shaping machine and one automatic exchange machine must be installed for each robot. Therefore, not only the equipment cost becomes huge, but also the space for installing them cannot be taken.

The present invention provides an apparatus that does not require an installation space for an automatic electrode shaping machine and an electrode exchanging machine, and can automatically perform electrode shaping and exchanging without manpower.

(Means for Solving the Problems) In the present invention, in a robot welding line for transporting an object to be welded by a trolley, one or more of the trolleys is provided with an electrode shaping machine and an electrode exchanger instead of the object to be welded. The electrode shaping machine, which is mounted, holds a robot-carrying electrode, first clamping means, a grinding tool that is rotationally driven by a motor, and an electrode that holds the grinding tool by the first clamping means. And a first moving means for moving the electrode holder with respect to the electrode holder. The electrode exchanging machine is provided with a second clamp means for holding an electrode holder held by the welding robot, and between the electrode holder and the electrode. An electrode extraction tool that is inserted to extract the electrode from the electrode holder by a wedge action, an electrode mounting tool that holds the electrode supplied from the feeder, and the electrode mounting tool that is held by the second clamp means. It is configured to include a second moving unit that moves the electrode holder that is held back and forth.

(Function) Since there are a trolley equipped with an electrode shaping machine and an electrode exchange machine, by teaching the welding robot the operations for electrode shaping and electrode exchange in advance, the dolly is positioned at the welding position at an appropriate timing. Then, the electrode is moved to the electrode shaping machine or the electrode exchange machine by the operation of the welding robot, and the electrode is automatically shaped by the operation of the first clamping means, the grinding tool, the first moving means, etc. in the electrode shaping machine, On the other hand, the electrodes are automatically replaced by the operation of the second clamping means, the electrode extracting tool, the second moving means, etc. in the electrode exchange machine.

(Embodiment) An embodiment of the present invention will be described below with reference to the drawings.

1 to 3 show a portion where welding is performed on the assembling transfer line 20, in which a carriage 21 on which an object to be welded (not shown) is placed moves on the line 20. To do. The dolly 21 is moved by the dolly moving device 22, and the dolly 21 usually has an object to be welded, for example, an automobile body, and by the welding robot 23 installed beside the transfer line 20, Welding work is now taking place. Hand truck
One out of every 21 cars does not have a car body. Instead, the electrode shaping machine 1 shown in FIGS. 4 and 5 described above, the electrode shaping machine 26 having the same structure as the electrode exchanging machine 10, and the electrode automatic shaping / replacement carriage 27 equipped with the electrode exchanging machine 26a are mixed, Electrode mounted on welding gun 24 of welding robot 23
Shape or replace 25.

The car body on the carriage 21 of the assembling transfer line 20 is welded by the welding gun 24 of the welding robot 23, but the electrode 25 at the tip of the welding gun 24 is used to weld several bodies. If it does, it will wear out and deform, so it will have to be shaped, and after several shapings, it will be shortened and must be replaced. In the present embodiment, after 10 cars with the car body placed on the carriage 21 have been installed, the electrode automatic shaping exchange carriage 27 comes and the electrodes are shaped automatically by the electrode shaping machine 26 of the carriage. Further, after 100 cars 21 on which the car body is mounted are replaced, the electrodes are replaced by the electrode exchanger 26a.

When the electrode shaping replacement cart 27 reaches the welding robot 23, the welding robot 23 does not perform the normal welding operation and is programmed to move the electrode 25 of the welding gun 24 into the electrode shaping machine 26. There is. Also, a cart for electrode shaping replacement
When 27 arrives at the welding robot 23, a power source and an air source (not shown) are automatically connected to the electrode shaping replacement cart 27. Then, the control device 28 in the electrode shaping / exchange cart 27 starts to operate and the electrode shaping is automatically performed.

Since the electrode shaping machine 26 has the same structure as the electrode shaping machine 1 in FIG. 4, the electrode clamping by the first clamp arm 5, the rotation of the grinding tool 4 by the air motor 6,
The same motion of advancing and retracting the grinding tool 4 by the cylinder 8 is controlled by the controller 28 to shape the electrode 25. When the shaping of the electrode 25 is completed, the next bogie 21 has the automobile body mounted thereon and the welding work similar to the previous one can be performed.

When 100 trucks 21 have passed, the electrode exchange is carried out by the electrode exchange 26a mounted on the electrode shaping exchange truck 27. When the electrode shaping exchange cart 27 reaches the welding robot 23, the welding robot 23 is programmed to move the electrode 25 of the welding gun 24 into the electrode exchange 26a.
When the electrode replacement carriage 27a comes to the welding robot 23, a power source and an air source (not shown) are automatically connected to the electrode shaping replacement carriage 17. Then, the control device 28 in the cart 27 for electrode shaping exchange starts to operate, and the electrode exchange is automatically performed. The electrode exchange 26a has the same structure as the electrode exchange apparatus 10 in FIG. 5, and is controlled by the controller 28 to perform the same operation to exchange the electrodes.

(Effects of the Invention) Since the present invention has the above-described configuration and operation, by using the method and apparatus of the present invention, electrodes on a trolley can be used for a plurality of welding robots arranged on a welding line. You can share the shaping machine and the electrode exchange machine,
As an example, 2 to 4 electrode shaping machines and electrode exchange machines are required for 100 robots, which greatly reduces equipment costs. In addition, all the problems related to the space for installing the electrode shaping device and the electrode exchanging device are eliminated.

Further, by arranging and circulating the electrode shaping exchange cart at an appropriate frequency, the electrodes in each process can be shaped and exchanged at an appropriate frequency, and the welding quality can be stabilized. In addition, the number of work steps is reduced, and since the electrodes are shaped by an electrode shaping machine on a regular basis, step-up control of the welding current is no longer necessary. Moreover, since the electrode or the electrode holder is held by the clamp means to shape or replace the electrode, the welding robot is not subjected to pressure during electrode shaping or electrode replacement, and a small robot can be used. Suitable for welding lines requiring robots.

[Brief description of drawings]

FIG. 1 is a front view of a welding line according to an embodiment of the present invention, FIG. 2 is a side view of an electrode shaping replacement cart, FIG. 3 is a plan view thereof, and FIG. 4 is a side view of a conventional electrode shaping device. 5 is a side view of a conventional electrode exchange device. 20 …… Conveying line for assembly, 21 …… Bogie 22 …… Bogie moving device, 23 …… Welding robot 26 …… Electrode shaping machine, 26a …… Electrode changer 27 …… Electrode shaping exchange cart

Claims (1)

[Claims] 1. In a robot welding line for transferring an object to be welded by a trolley, one or more of the trolleys is equipped with an electrode shaper and an electrode exchanger instead of the object to be welded, and the electrode shaper comprises: The first to hold the electrode that the robot has
And a first moving means for moving the grinding tool forward and backward with respect to the electrode held by the first clamping means. The exchange is provided with second clamp means for holding an electrode holder held by a welding robot, an electrode extracting tool for inserting the electrode from the electrode holder by a wedge action inserted between the electrode holder and the electrode, and a feeder. And a second moving means for moving the electrode mounting tool forward and backward with respect to the electrode holder held by the second clamp means. Automatic welding electrode shaping and replacement device.