JPH0435014Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> This invention is a transport robot that holds a workpiece in a workpiece holder attached to the arm of the robot and transports the workpiece to the welding gun position of a welding machine for welding. This relates to the welding equipment used.

<Prior Art> In conventional welding equipment used with robots that hold and transport workpieces, the welding gun is fixedly mounted vertically on a base (see, for example, Japanese Utility Model Publication No. 1983-48067). For example, when welding both horizontal and vertical parts of a workpiece, the horizontal part of the workpiece held by the robot is first positioned between the upper and lower tips of the welding gun, and then the robot's arm is welded. The robot arm is pivoted laterally to separate the workpiece from the welding equipment, the arm is then rotated about 90 degrees about its axis, and the arm of the robot is again pivoted in the opposite direction to separate the workpiece from the welding device. It became necessary to weld by positioning the vertical part between the upper and lower chips of the welding gun.

<<Problems to be solved by the invention>> However, with such conventional welding equipment, when welding horizontal and vertical parts of a workpiece, the robot's arm must be rotated approximately 90 degrees around its axis. This not only reduces welding accuracy compared to when the robot arm does not rotate, but also requires the robot arm to move a sufficient distance from the welding gun during this rotation, and this pivoting motion The welding cycle was long because the welding was carried out in a timely manner.

Therefore, the purpose of the present invention is to eliminate the need to rotate the arm of the robot that holds the workpiece when welding the horizontal and vertical parts of the workpiece, thereby improving welding accuracy. Therefore, it is an object of the present invention to provide a welding device using a transport robot that can shorten the welding cycle.

《Means for solving the problem》 In order to achieve the above purpose, in a device that performs welding by holding a workpiece in a workpiece holder attached to the arm of a robot and transporting it to the position of the welding gun of a welding machine, The welding gun is formed in a C-shape from the base end to the distal end, has a fixed tip at the distal end, and is movable toward and away from the fixed tip at the proximal end, and can be retracted from the interfering position of the workpiece. The welding gun has a movable tip, and the welding gun is attached to a pivot installed horizontally on the base of the welding machine so as to be able to swing up and down about the pivot, and the welding gun is formed by the fixed tip and the movable tip. In order to make the welding position face the horizontal and vertical welding parts of the workpiece, the welding gun is provided with a drive means that swings and displaces the welding gun so as to be switchable between a horizontal state and a vertical state to a plurality of welding positions. The welding gun is provided with a pair of stopper members on the base, with which the swinging welding gun abuts in a vertical state and a horizontal state.

<<Operation>> For example, when a workpiece has a horizontal part to be welded and a vertical part to be welded, and the horizontal part to be welded is to be welded first, the driving means is activated to move the welding gun around the horizontal axis. swing upward in a vertical plane, and place it in a vertical position by abutting one stopper member. At this time, the C-type welding gun is in a horizontally open position where the welding position formed by the gap between both chips faces the workpiece from the front. In this state, the workpiece was held in a workpiece holder attached to the arm of the robot, and the arm was rotated laterally to transport the horizontal part of the workpiece to be welded to the welding position of the welding gun and then evacuated. Extend the movable tip and perform welding. When welding of this horizontal part to be welded is completed, the movable chip is retracted and the arm of the robot is pivoted laterally to separate it from the welding machine. Then,
In the same manner as described above, the driving means is driven to swing the welding gun downward by approximately 90 degrees so as to contact the other stopper member, and the welding gun is switched to a horizontal position. At this time, the welding gun is in a vertically open position where the welding position formed by both chips faces the workpiece from above. Then, the arm of the robot is moved laterally again to transport the vertical part of the work to be welded to the welding position of the welding gun, and the movable tip is extended to perform welding. When welding of the vertical part to be welded is completed in this manner, the arm of the robot is again swiveled laterally to move the workpiece to the next station.

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

Figure 1 shows a workpiece transfer robot 1 and a welding machine 10.
This robot 1 has a swivel base 3 that can be rotated horizontally on a fixed base 2. This swivel base 3 has a support leg base 4 that can swing back and forth.
is supported, and an arm 5 is mounted at the upper end of this support leg 4.
is installed. A work holder 7 is attached to the lower end of the arm 5 via a drive head 6. This work holder 7 holds a work 8 consisting of two members to be welded, for example a work consisting of two members such as a rear quarter inner panel 8a and a wheel house panel 8b of a vehicle body.

The welding machine 10 has a frame-shaped base 1 with a hollow center.
1, and a bracket 1 at the upper part of this base 11.
The central base of a C-shaped welding gun 14 is pivotally attached to the welding gun 2 by a pivot 13, so that the welding gun 14 can swing vertically within a vertical plane. A short and small fixed tip 15 is fixed to the lower surface of the tip of this C-type welding gun 14, and a gun cylinder 16 is integrally fixed to the lower part of the welding gun 14, and a relatively long movable tip 17 is attached to this gun cylinder 16.
is telescopically housed and located on the same straight line as the fixed chip 15. Furthermore, an air cylinder 18 is disposed between the upper rear surface of the C-type welding gun 14 and the upper surface of the base 11.
The cylinder part 8 is attached to the bracket 1 on the base 11.
It is pivoted to 9. On the other hand, the tip of the piston rod 20 of the air cylinder 18 is rotatably connected to a bracket 21 attached to the upper rear surface of the welding gun 14 by a pin 22.

A first stopper member 23 is attached to the front surface of the upper end of the base 11.
3 is adapted to come into contact with the upper rear surface of the welding gun 14 when the welding gun 14 is in a vertical position. Also, on the upper surface of the hollow interior of the base 11, a pin 13 is located at the center.
The second stopper member 2 is placed at a position rotated by 90°.
4 is installed.

Note that a gun cylinder 1 is located below the welding gun 14.
A pressurized air supply pipe 25 for driving the gun cylinder 16 is attached adjacent to the gun cylinder 6 .

In the state shown in FIGS. 1 and 2, the arm 5 of the workpiece transfer robot is driven to swing horizontally, the workpiece 8 is set at a predetermined welding position, and then the welding gun 14 is swung. The piston rod 20 of the air cylinder 18 is extended, and the welding gun 14 is brought down to a horizontal position. At this time, the movable tip 17 is attached to the gun cylinder 1 in advance.
The workpiece 8 is housed in the workpiece 6, and a substantially vertical portion of the workpiece 8 to be welded is inserted between the fixed chip 15 and the fixed chip 15. From this state, gun cylinder 1
6 is driven, the movable tip 17 is extended, and the welded part is held between it and the fixed tip 15, and spot welding work is performed. When this one spot welding is performed, the drive head 6 that suspends and supports the workpiece holder 7 is driven, and the other perpendicular welded part adjacent to the spot welded part is welded on both chips 1.
5 and 17, the next spot weld is performed, and this welding operation is repeated.

In this way, when welding of all the vertical welded parts is completed, the movable tip 17 is shortened and separated from the workpiece 8. Next, the driving air cylinder 18 of the welding gun 14 is driven and its piston rod 20 is retracted, and the welding gun 14 is moved to the shaft 13.
It stands up by swinging upwards around the center. After that, the arm of the robot 1 is once pivoted in the lateral direction, the support leg 4 is tilted to raise the workpiece attached to the tip of the arm 5, and the arm is pivoted in the opposite direction to the welding gun. A horizontal part of the workpiece 8 to be welded is positioned between both chips 15 and 17 of the workpiece 14. After that, the lower movable tip 17 is extended, and as shown in FIG.
Spot welding is carried out by holding a horizontal part to be welded in between, and the welding operation is carried out by operating the drive head and sequentially changing the welding position in the same way as in the previous case. When such welding work is completed, the movable tip 17 is retracted into the gun cylinder 16 and separated from the workpiece 8. Thereafter, the arm 5 of the robot 1 is rotated horizontally to transport the work 8 to the next station.

In addition, in the description of the above embodiment, the welding gun 14 is first explained.
The welding gun 14 is tilted horizontally to weld the vertical part of the workpiece, and then the welding gun 14 is raised vertically to weld the horizontal part of the workpiece. However, this welding order can be reversed. It goes without saying that this can be done.

In addition, in the above embodiment, the welding gun can be swung in two positions, the vertical position and the horizontal position, but the air cylinder that swivels the welding gun in the vertical direction is configured in multiple stages, so that the welding gun can be moved in three or more positions. It is possible to occupy the welding position.

<<Effects>> In the welding device using the transport robot according to the present invention, the C-type welding gun moves the welding position formed by its fixed tip and movable tip to the horizontal and vertical parts of the workpiece. The welding tip is made up of a gap between a fixed tip and a movable tip, which can be swung vertically around a horizontal axis in a vertical plane to switch between a horizontal state and a vertical state in a plurality of welding positions. Since multiple welding positions can be secured from the horizontal open position to the vertical open position, when welding the horizontal and vertical parts of the workpiece, the robot holding the workpiece can Since there is no need to rotate the arm approximately 90 degrees around its axis as in conventional methods, it not only improves welding accuracy but also has excellent effects such as shortening the welding cycle. It is.

[Brief explanation of drawings]

Fig. 1 is a perspective view showing the entire welding device using a transport robot according to the present invention, Fig. 2 is a partially sectional side view of the welding machine in Fig. 1, and Fig. 3 shows welding from the state shown in Fig. 1. FIG. 3 is a partially sectional side view showing a state in which the gun is raised vertically and a horizontal part to be welded is welded. 1... Transport robot, 5... Arm, 7...
Work holder, 8... Work, 10... Welding machine,
14... Welding gun, 15, 17... Chip, 18
……cylinder.

Claims (1)

[Scope of Claim for Utility Model Registration] In a device that performs welding by holding a workpiece in a workpiece holder attached to the arm of a robot and transporting it to the position of a welding gun of a welding machine, the welding gun is The welding gun is formed in a C-shape, has a fixed tip at its distal end, and has a movable tip at its proximal end that can be moved toward and away from the fixed tip and can be retracted from the interfering position of the workpiece. , is attached to a pivot installed horizontally on the base of the welding machine so as to be able to swing vertically about the pivot, and the welding position formed by the fixed tip and the movable tip is moved horizontally to the workpiece to be welded. The welding gun is provided with a drive means that allows the welding gun to be oscillated between a horizontal state and a vertical state so as to be able to switch freely between a plurality of welding positions, and the base is provided with a oscillating means to allow the welding gun to face the welding part and the part to be vertically welded. 1. A welding device using a transport robot, characterized in that the moving welding gun is provided with a pair of stopper members that abut in a vertical state and a horizontal state.