JPH0335501Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a resistance welding gun, and particularly to a resistance welding gun suitable for welding a tunnel portion of an automobile body.

Conventional technology For example, a tunnel is formed in the center of the floor of an automobile body to pass a propeller shaft, harness, etc., and this floor is constructed by joining the front floor, rear floor, etc. by spot welding. are doing.

As a welding gun for welding the tunnel portion of the vehicle body, a device disclosed in Japanese Patent Application Laid-Open No. 124582/1982 is known. This will be explained with reference to FIG. 2 as follows. In Fig. 2, 1 is a C-shaped support arm fixedly attached to the frame 2, 3 is a mounting bracket rotatably pivoted to the upper end 4 of the support arm 1 via a pin 5, and 6 is the above-mentioned mounting bracket. 3 is a pressure cylinder mounted and fixed in a predetermined inclined position; 7 is a pressure cylinder mounted and fixed in a predetermined inclined position on the lower end 8 of the support arm 1; 9 and 10 are rods of the pressure cylinders 6 and 7. The movable electrodes 9 and 10 are attached to the ends of the movable electrodes 11 and 12, and these movable electrodes 9 and 10 are provided facing each other. A swing cylinder 13 is rotatably attached to the upper surface of the upper end portion 4 of the support arm 1 via a pin 14. This swing cylinder 13 moves the pressure cylinder 6 to the pin 5.
Rotate around the fulcrum. Cables 15 and 16 are electrically connected to the movable electrodes 9 and 10.
Reference numeral 17 denotes a work such as a floor having a tunnel portion 18.

Next, the operation of the conventional resistance welding gun will be explained as follows.

The support arm 1 moves and the movable electrodes 9, 10
are held at predetermined positions on both sides of the inclined wall 18a of the tunnel portion 18 of the workpiece 17, the swing cylinder 13
By this operation, the pressure cylinder 6 rotates about the pin 5, and the movable electrodes 9 and 10 face each other so that their axes coincide. After that, the pressure cylinder 6,
7 is activated, the movable electrodes 9 and 10 are sufficiently pressed against the welding site of the tunnel portion 18 of the workpiece 17, and pressure welding is performed. When the pressure welding is finished in this way, the movable electrodes 9 and 10 retreat to their original positions, and then the support arm 1 moves along the workpiece 17, and the movable electrodes 9 and 10 are held at the next welding position, and the movable electrodes 9 and 10 are moved back to their original positions. Pressure welding is performed in the same manner.

Problems to be Solved by the Invention Since the above-mentioned conventional resistance welding gun has a movable electrode held in a predetermined inclined position, it cannot be used for pressure welding of parts other than the inclined wall 18a of the tunnel portion 18 of the workpiece 17. Therefore, there was a problem that the operating efficiency was extremely poor. Moreover, in order to pressure weld the inclined wall 18a of the tunnel portion 18 of the workpiece 17, it is necessary to install resistance welding guns at symmetrical positions, which increases the cost and requires a large installation space. There was a problem in that it was not possible to use it effectively.

Means for Solving the Problems The present invention has been proposed in view of the above problems, and includes a fixed support arm 22a fixedly supported by the frame 21 and a first parallel link mechanism 24. A movable support arm 22b is provided to move parallel to the arm 22a, and the fixed support arm 22a and the movable support arm 22b are disposed oppositely at the ends of the fixed support arm 22a and the movable support arm 22b so as to be rotatable in the longitudinal direction of each arm 22a, 22b, and Second parallel link mechanism 3
5, and opposing electrodes 40a, 40b provided on rods 41a, 41b of the pressure cylinders 32a, 32b. .

Effect: In the present invention, two pressurizing cylinders provided with opposing electrodes are always rotated in a state in which their centers are aligned, and the electrodes can be held in a desired angular posture. Therefore, it is possible to pressure weld not only the tunnel portion but also the horizontal portion of the workpiece with one resistance welding gun.

Embodiment An embodiment of the present invention will be described below with reference to FIG. 1. In Figure 1, 21
22a is a fixed support arm that is fixedly supported via a bracket 23; 22b is a movable frame that is provided to move parallel to the fixed support arm 22a by a first parallel link mechanism 24; It is a support arm. The parallel link mechanism 24 connects both ends 28a and 28b of the swing link 27 to the base ends 25a and 25b of the fixed support arm 22a and the movable support arm 22b, respectively, with pins 2.
Both ends 30a, 30b of the parallel link 29, which is rotatably connected via pins 6a, 26b and arranged parallel to the swing link 27, are connected to the pin 31.
It is rotatably pivoted to the fixed support arm 22a via a and 31b. 32a, 32b
Pins 34a,
The two pressure cylinders 32a, 32b are always aligned with each other by the second parallel link mechanism 35. is maintained. The second parallel link mechanism 35
Connecting rods 37a, 37b are arranged parallel to the fixed support arm 22a and the movable support arm 22b at the outer ends of the pressure cylinders 32a, 32b and at the tips of the tapered parts 36a, 36b at both ends of the swing link 27.
Both ends 38a, 38a, 38b, 38b are rotatably connected via pins 39a, 39a, 39b, 39b, and the connecting rods 37a, 37b are rotated by the rotation of the swing link 27. At the same time, the pressure cylinders 32a, 32b and the tapered portions 36a, 36b at both ends of the swing link 27 rotate about the pins 34a, 34b, 26a, 26b as supporting points and move in parallel. Reference numerals 40a and 40b are electrodes attached to opposite ends of the rods 41a and 41b of the pressure cylinders 32a and 32b, and 42 is the electrode 4.
This is means for adjusting the angular posture of 0a and 40b.
In the adjusting means 42, 43 is a rotary screw shaft 4.
4, this actuator 4
3 is a base end portion 25a of the fixed support arm 22a;
A pin 46 is attached to the tip of the mounting arm 45 that is attached and fixed to the
It is pivotably connected via the. Reference numeral 47 denotes a guide member having a screw hole (not shown) that is swingably attached to the outer end surface 48 of the swing link 27, and the rotary screw shaft 44 of the actuator 43 is screwed into the thread hole of the guide member 47. It has been inserted. 49 is a work such as a floor of a car body having a tunnel part 50,
This work 49 is positioned and fixed at a fixed position by appropriate means.

Next, the operation of the present invention will be explained as follows.

When the frame 21 moves forward and the electrodes 40a and 40b are located above and below the tunnel portion 50 of the workpiece 49, the actuator 43 is actuated to remove the electrodes 40a and 40b.
Adjust the angular posture of a and 40b. That is, first, when pressure welding the inclined wall 50a of the tunnel portion 50 of the workpiece 49, the actuator 43 is operated to rotate the rotary screw shaft 44 in a predetermined direction. Then, the guide member 4 attached to the swing link 27
7 and the rotary screw shaft 44 are screwed together,
The guide member 47 moves to the right along the rotating shaft 44. As the guide member 47 moves, the swing link 27 rotates by a predetermined angle clockwise about the pin 26a, and at the same time, the first parallel link mechanism 24
Due to this, the movable support arm 22b becomes the fixed support arm 2.
It moves parallel to the right direction with respect to 2a. Then, the connecting rod 37a of the second parallel link mechanism 35 moves in parallel to the left, and the connecting rod 37b moves in parallel to the right. 36b moves in parallel, and due to this parallel movement, the pressurizing cylinders 32a, 32b rotate in a state in which they are centered around the pins 34a, 34b as fulcrums. In this way, the electrode 40
When a and 40b face each other in a predetermined inclined posture through the inclined wall 50a of the tunnel portion 50 of the workpiece 49,
The pressurizing cylinders 32a, 32b are operated, and the electrodes 40a, 40b are applied to the inclined wall 5 of the tunnel portion 50.
Pressure welding is performed by sufficiently pressing onto 0a from both sides with the same pressing force.

Further, when pressure welding the inclined wall 50b on the opposite side of the tunnel portion 50 of the workpiece 49, the actuator 43 is operated to rotate the rotary screw shaft 44 in the opposite direction. Then, the guide member 47
moves to the left along the rotating screw shaft 44, and the swing link 27 rotates a predetermined angle counterclockwise about the pin 26a, and at the same time, the movable support arm 22b is fixedly supported by the first parallel link mechanism 24. It moves parallel to the left direction with respect to the arm 22a. With the movement of the movable support arm 22b to the left,
The connecting rod 37a of the second parallel link mechanism 35 moves in parallel to the right, and the connecting rod 37b moves in parallel to the left. is moved in parallel, and due to this parallel movement, the pressurizing cylinders 32a, 32b rotate in a state in which they are centered around the pins 34a, 34b as fulcrums. And electrode 4
When 0a and 40b face each other in a predetermined inclined posture through the inclined wall 50a of the tunnel portion 50 of the workpiece 49, the pressurizing cylinders 32a and 32b are activated, and the electrodes 40a and 40b are connected to the inclined wall 50 of the tunnel portion 50.
0b from both sides with the same pressing force to perform pressure welding.

In the above embodiment, the actuator 43 is used to adjust the tilted posture of the electrodes 40a, 40b, but this posture adjustment is performed manually by the operator without using the actuator. Good too. Further, in the above embodiment, the case of pressure welding the floor of an automobile body was explained, but the present invention is not limited to this, and can be used for pressure welding of the tunnel part of any workpiece. . Furthermore, the present invention can be used for pressure welding of horizontal parts of workpieces as well as tunnel parts of workpieces.

Effects of the invention According to the invention, not only the tunnel part of the workpiece but also the horizontal part can be pressure welded with one resistance welding gun, and each part can be pressure welded continuously. In addition to being able to significantly improve workability, it also has versatility and extremely high operating efficiency. Further, since two resistance welding guns are not required as in the conventional method to pressure weld the tunnel portion of the workpiece, the cost is low and the work space can be used effectively.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a resistance welding gun according to the present invention. FIG. 2 is an explanatory diagram of a conventional resistance welding gun. 21... Frame, 22a... Fixed support arm, 22b... Moving support arm, 24... First parallel link mechanism, 32a, 32b... Pressure cylinder, 35... Second parallel link mechanism, 40a, 4
0b...electrode, 41a, 41b...rod.

Claims (1)

[Scope of utility model registration request] a fixed support arm fixedly supported on the frame;
A movable support arm provided to move in parallel with the fixed support arm by a first parallel link mechanism, and a movable support arm that faces the ends of the fixed support arm and the movable support arm so as to be rotatable in the longitudinal direction of each arm. A resistance welding gun comprising two pressure cylinders arranged and kept aligned by a second parallel link mechanism, and opposing electrodes provided on the rods of the pressure cylinders.