KR900003638B1 - Robot for spot welding - Google Patents

Abstract

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Description

Robot for spot welding

1 is a front view of a robot for spot welding according to an embodiment of the present invention.

2 is a front view of the welding gun used in the robot shown in FIG.

3 is a cross-sectional view of the pivot joining mechanism.

* Explanation of symbols for main parts of the drawings

1: Robot hand (hand means) 2: Spot welding gun (welding means)

2a: base 2b: support

3: air cylinder (welding gun operating means) 3a, 3b: hose connector

3c: electrode support member 4: robot arm

4a, 4b: End of robot arm 4c: Hose clamp

6: robot body assembly 6a: robot body

6b: 2nd pillar 6c: lower end

7: fixed base 7a: end wall

8: Swivel joint part (swivel joint means) 8a: Fixed joint member (fixed part)

8b: rotary joint member (moving part) 9: conduit means (general term for 9a, 9b, 9c)

9a, 8b: Coolant hose 9c: Compressed air hose

10: pivot support 11: bending member

12: rotating member 13: head cover

14: swingable column 14a: lower end

14b: pillar cover 15: fixed electrode

15a, 15b, 16a, l6b: coolant passage 16: movable electrode

17: cooling water supply passage 18: cooling water return passage

19: compressed air passage 17a, 18a, 19a: annular groove

17b, 18b, 19b: radial passages 17c, 18c, 19c: cooling water pipes

17d, 18d, 19d: Pipe 17e, 18e, 19e: Pipe Connecting Mechanism

17f, 18f, 19f: coolant passage 20: pipe connecting mechanism

21: vertical tube 22: control valve

22a: pressure inlet 24: bearing

25: lower link

The present invention relates to an industrial welding robot, in particular, a spot welding robot, and more particularly, to an industrial spot welding robot having a conduit for supplying a cooling medium and / or a fluid for operating a welding gun to a welding gun. will be.

Spot welding is a true resistance welding technique, which involves overlapping two or more sheets of metal, placing the overlapping plates between a pair of electrodes, and forming welded spots on the sheet. And a process of applying a pressing force through the electrode to the overlapped metal plate while applying current through the electrode.

In this welding process, not only do the electrodes apply current, but also the pressing pressure, these electrodes are subjected to a temperature rise.

In order to suppress the temperature rise, the electrodes are usually made of copper alloy with good thermal conductivity, and various facilities are provided for effective liquid cooling of the electrodes.

Traditionally, spot welding robots currently employed in automobile manufacturing plants are called spot welding guns of type C or X spot welding guns comprising a pair of electrodes or spot welding guns having a retracting electrode and a stud gun. Equipped with. The welding gun is usually installed in the hand of the robot operated by the control unit in accordance with the type of work previously informed to the robot.

In modern welding robots, welding can be performed quickly and with high accuracy according to the schedules previously informed to the robots, even in locations that are difficult to reach by human hands.

Therefore, welding robots are now essential for mass production in manufacturing plants.

In a conventional welding robot, a conduit for supplying a cooling medium and a welding gun operating fluid is supported on a pile provided in the side portion of the robot body for this purpose, and is connected with an appropriate portion of the robot hand.

In another configuration, the conduit of the cooling medium and the welding gun operating fluid is supported on the ceiling of the factory building. In order to prevent the movement of the robot from being obstructed by the conduits, these conduits must be slightly stretched between the robot hand and the support pile or ceiling.

Therefore, in the conventional configuration, it was necessary to adjust the length of the conduits after the installation of the robot. More specifically, first of all, the robot body is installed at a predetermined position, and then the conduits are connected to the necessary portion, with appropriate adjustment of the conduit length for the required slack of the conduit.

Therefore, a lot of time and effort are required for the installation of the conduit. In addition, in the conventional robot, since a conduit support pile to be located in the vicinity of the robot body is required, the space for arranging the robot is increased.

Another disadvantage of the conventional arrangement is that the fluid conduits for the cooling medium and the welding gun action are arranged in a relatively unstable manner because they hang on the support pile or ceiling. The conduits arranged in this way frequently come into contact with the robot body and the support pile during operation of the robot. Moreover, because these conduits are repeatedly pulled and bent as the robot arm moves, they are used under conditions that are very easily damaged.

In addition, conventional robots also have the disadvantage that movement is limited by conduits.

It is therefore an object of the present invention to provide an industrial welding robot that has a cooling medium and a conduit for fluid supply for welding gun operation, but does not require external means such as support piles for the conduit.

Another object of the present invention is to provide an industrial welding robot that essentially eliminates the possibility of damage to the conduits.

It is still another object of the present invention to provide a welding robot that can significantly reduce the time and effort of installing a conduit for supplying fluid for cooling medium and welding gun operation.

According to the present invention, the above and other objects, on the other end of the arm means to move around at least one axis, and the arm means having its one end mounted on the body so as to pivot Hand means, which is installed and carries a welding gun means, conduit means through which fluid can pass, and pivot joining means provided between one end of the arm means and the base and having a fixed portion and a movable portion A conduit means comprising: a first portion located within said base and connected with a fixed portion of said pivotal joining means, and a second portion located along said arm means and connected with a movable portion of said pivotal joining means; Branches can be achieved by a welding robot.

In one aspect of the present invention, the conduit means is a means for supplying a cooling medium to the welding gun means.

In another aspect of the present invention, the welding robot includes actuator means for operating the welding gun means to move the hand means, wherein the conduit means is a means for supplying a working fluid to the actuator means.

The above and other objects and features of the present invention will become apparent from the description of the preferred embodiments with reference to the accompanying drawings.

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

First, in FIG. 1, the welding robot with the fixed base 7 fixed to the factory floor is shown. On this base 7, the robot body assembly 6 is mounted so that it can pivot about its vertical axis. This robot body assembly (6) has a body (6a) mounted on the base (7) for the above-described pivoting movement, and a pillar cover (14b) on which the lower end thereof is mounted on the body (6a). A swingable pillar 14.

The second pillar 6b is provided to extend in parallel with the pillar cover 14b. The howling 25 is provided between the bottom end portion 14a of the pillar cover 14b and the bottom end portion 6c of the second pillar 6b.

One end of the lower link 25 is rotatable with the lower end 14a of the pillar cover 14b and the other end with the lower end 6c of the second pillar 6b, respectively. Connected.

The upper ends of the pillars 14 and 6b are rotatably connected to the head cover 13 so that the head cover 13, the pillars 14 and 6b, and the lower link 25 ) Forms a parallelogram that is oscillable between the vertical position shown by the solid line in FIG.

The rocking motion of these pillars 6b and 14 occurs by an actuator provided in the body 6a. One end 4b of the robot arm 4 is mounted on the head cover 13.

At the other end of the robot arm 4, a pivot support 10, a flexure member 11 mounted on the pivot support 10, and a pivot member 12 mounted on the flexure member 11 are provided. The robot hand 1 (hand means) containing the back) is provided. The spot welding gun 2 (welding gun means) is mounted on the rotating member 12.

The actuator of the robot hand 1 is installed in the head cover 13. FIG. 2 shows a welding gun 2 composed of a base portion 2a attached to the pivot member 12 other than the robot hand 1, and a support 2b extending downward from the base portion 2a. Is shown. A fixed electrode 15 is mounted on the lower end of the support 2b.

At the upper end of the support 2b, an air cylinder 3 (welding gun operating means) having a piston rod for moving the electrode support member 3c for moving the movable electrode 16 is mounted.

The air cylinder 3 includes hose connectors 3a and 3b for connecting with an air hose provided to supply compressed air to the air cylinder 3.

The air cylinder 3 acts to actuate the movable electrode 16 toward or away from the fixed electrode 15, as indicated by the arrows in FIG.

It should be noted in FIG. 2 that the coolant passages 15a and 15b are formed in the support 2b so that the coolant circulates through the fixed electrode 15.

Similarly, the coolant passages 16a and 16b are formed in the electrode support member 3c so as to circulate the coolant through the movable electrode 16.

It should be noted in FIG. 1 that the coolant hoses 9a are connected to the coolant passages 15a and 15b in the support 2b. In a similar manner, the coolant hoses 9b are connected to the coolant passages 16a and 16b in the electrode support member 3c. Compressed air hoses 9c for welding gun operation are connected to hose connectors 3a and 3b, respectively, to supply compressed air to the welding gun operating cylinder 3.

The hoses 9a, 9b and 9c (9, conduit means) pass along the robot arm 4 and are supported by hose clamps 4c mounted on the robot arm 4.

The pillar cover 14b of the robot body assembly 6 is hollow and the hoses 9a, 9b and 9c pass through the empty interior of the pillar cover 14b.

It should be noted in FIG. 3 that the robot body 6a is mounted on the base 7 so as to pivot about the vertical axis by means of bearing 24 means.

On the robot body 6a, the pivot joint 8 (swivel joint means) comprised of the stationary joint member 8a (fixed part) and the rotary joint member 8b (movable part) is provided. The joining members 8a and 8b are coaxial with each other, and the rotary joining member 8b is fitted to the stationary joining member 8a. More specifically, the fixed joint member 8a has a cylindrical outer surface, while the rotary joint member 8b has a cylindrical inner surface, and the cylindrical outer surface of the fixed joint member 8a is the rotary joint member 8b. Is fitted on the cylindrical inner surface of the

In the bass 7, a pipe connecting mechanism 20 fixed to the base 7 is provided, and the pipe connecting mechanism 20 is a vertical tube 21 extending upward from the connecting mechanism 20. Has The fixed joint member 8a is supported by the vertical tube 21 at the upper end of the vertical tube 21. In the stationary joining member 8a, one end is opened to the bottom surface of the joining member 8a, and the other end is a coolant supply passage 17 opened at the cylindrical side of the joining member 8a, and a coolant return passage. 18 and a compressed air passage 19 are formed.

As shown in FIG. 3, these passages 17 and 18 are open at the lowest position and the highest position of the side surface of the joining member 8a, respectively, and the passage 19 is the passage 17. As shown in FIG. And at a position between and (18).

In the rotary joint member 8b, annular grooves 17a, 18a, and 19a are formed on the inner surface thereof so as to communicate with the passages 17, 18, and 19, respectively.

In addition, the joining members 8b are also provided with radial passages 17b, 18b and 19b extending outwardly from the annular grooves 17a, 18a and 19a, respectively. One of the coolant hoses 9a and one of the coolant hoses 9b are connected to the radial passage 17b via a pipe connecting mechanism 17e in the rotary joint member 8b, and the other 1 Hoses 9a and 9b are connected to the radial passage 18b via a pipe connecting mechanism 18e.

The passages 17 and 18 in the fixed joint member 8a are connected to the pipes 17d and 18d extending between the joint member 8a and the pipe connecting mechanism 20, respectively.

The pipe connecting mechanism 20 is provided with cooling water passages 17f and 18f connected to the pipes 17d and 18d, respectively. In the bass 7, cooling water pipes 17C and 18c connected to the passages 17f and 18f respectively in the pipe connecting mechanism 20 are provided. Inside the pillar cover 14b of the robot body assembly 6, the compressed air hose 9c has a control valve having a pressure inlet 22a connected to the radial passage 19b in the rotary joint member 8b. 22) is connected. The valve 22 alternately connects the radial passage 19b to one or the other of the hoses 9c. The compressed air passage 19 in the fixed joining member 8a is connected to a pipe 19d in the tube 21. This pipe 19d extends between the joining member 8a and the pipe connecting mechanism 20 in which the compressed air passage 19f is formed.

The passage 19 is also connected to a pipe 19c provided in the bass 7.

The pipes 17c, 18c and 19c are open at one end wall 7a of the base 7 and are connected to a suitable fluid source not shown in the drawing.

Although not shown in the drawings, this welding robot has an electronic control unit for operating the robot in the order previously known to the robot, and this feature is already well known in the industrial welding robot art, and thus the detailed description thereof will be omitted. .

The welding robot is adapted to extend the hoses 9a, 9b and 9c with flexibility that extends along the oscillating robot arm 4 and also extends into the empty interior of the robot body assembly 6. Equipped.

Thus, the robot can be assembled with a conduit for supplying a fluid for welding gun operation to circulate the coolant in advance, and then installed in the place where the robot should be operated. In the installation of the robot, it is only necessary to connect the pipes described above to a suitable fluid source. Thus, the time and effort for installing the robot is significantly reduced. Moreover, the life of the conduit can be increased because these pipes and hoses can be prevented from contacting other parts located near the robot.

Although the present invention has been shown and described with reference to specific embodiments, it is not limited to the details of the illustrated structure, and various modifications and changes may be made without departing from the scope of the appended claims.

Claims (5)

A fixed means (7), an arm means whose one end is mounted on the body for pivotal movement, and an other end of the arm means so as to move around at least one axis, and a welding gun means ( 2) a hand means (1) for carrying, a conduit means (9) through which fluid can pass, and a fixed portion (8a) installed between one end of the arm means and the base (7). And a pivot joining means (8) having a movable portion (8b), wherein the conduit means (9) is located in the base (7) and is a fixed portion (8a) of the pivot joining means (8). And a second portion connected to the arm portion and a first portion positioned along the arm means and connected to a movable portion (8b) of the pivot joint means (8). The robot for spot welding according to claim 1, characterized in that the conduit means (9) is a means for circulating a cooling medium through the welding gun means (2). The method according to claim 1, further comprising a welding gun operating means (3) for operating the welding gun means (2), wherein the conduit means (9) operates a welding gun on the welding gun operating means (3). A robot for spot welding, characterized in that it is a means for supplying a fluid. The robot for spot welding according to claim 3, wherein the welding gun operating fluid is compressed air. 2. The arm according to claim 1, wherein the arm means includes pivot body means for mounting one end thereof on the base to pivot about one axis, and pivotable arm connected to the other end of the pivot body. And the conduit means (9) extend within the pivot body means and are arranged to extend outwardly along the pivotable arm.

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