JPH023673B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a torch holding device for an automatic welding machine generally called a welding robot.

When welding various parts of a workpiece using an automatic welding machine, such as horizontal or vertical butt welds, horizontal or vertical fillet welds, and other various weld parts, these parts The torch posture (angle with respect to the workpiece) must be changed depending on the type of workpiece. Furthermore, since the torch is automatically moved along the welded part on the workpiece under automatic program control, it is desirable that the position of the welding point at the tip of the torch not be displaced relative to the automatic welding machine even if the torch position is changed. .

As a torch holding device that satisfies these conditions, for example, a parallel link method (Japanese Patent Laid-Open No. 52-109450
) and the torch oscillation rotation method using gears (Tokukosho
54-3646), but the former parallel link method has a large number of parts and fulcrums, so it is not only prone to play and has poor durability.
The disadvantage is that the whole thing is large. Furthermore, the latter torch oscillation method has a fatal drawback in that the torch angle cannot be changed continuously along a two-dimensional vertical plane.

The present invention provides a torch holding device that can eliminate the drawbacks of the conventional methods as described above, and one embodiment thereof will be described below with reference to the attached illustrative drawings.

In Fig. 1, 1 is a welding robot body, which is movable in the horizontal X-axis direction and the horizontal Y-axis direction, and a robot hand 2 that can be raised and lowered in the vertical Z-axis direction.
It is equipped with A torch holding device 3 of the present invention is attached to the lower end of this robot hand 2.

As shown in FIGS. 2 and 3, the torch holding device 3 includes a main body 4 attached to the lower end of the robot hand 2, and a main body 4 that is pivotably supported around a first support shaft 5. The torch support 8 is equipped with a swinging arm 6 and a torch support 8 that is swingably supported at the tip of the swinging arm 6 around a second support shaft 7 that is parallel to the first support shaft 5. The distance between the tip welding point 10 of the torch 9 held at 8 and the second support shaft 7
La and the distance between the first support shaft 5 and the second support shaft 7
A first transmission wheel 11 fixed to the main body 4 concentrically with the first support shaft 5 and fixed to the torch support 8 concentrically with the second support shaft 7 with a ratio of 1:1 to Lb. and a second transmission wheel 12 having a diameter half that of the first transmission wheel 11 (in the case of a toothed wheel, the number of teeth is half).
A means 14 for swinging the swinging arm 6 with respect to the main body 4 is provided, on which an endless rotating body 13 for transmission is suspended.

In the illustrated embodiment, the first support shaft 5 is fixed to the main body 4, the first transmission wheel 11 is fixed to the first support shaft 5, and the upper end of the swing arm 6 is fixed to the first support shaft 5. 5 is rotatably supported. Further, the second support shaft 7 is fixed to a torch support 8, the second transmission wheel 12 is fixed to this second support shaft 7, and the lower end of the swing arm 6 is rotated around this second support shaft 7. It is pivoted for free movement. The means 14 includes a toothed wheel 16 fixed to the swinging arm 6 via a rotary shaft 15 rotatably loosely fitted to the first support shaft 5, and a driving chain 17 suspended from the toothed wheel 16. In preparation, this chain 16
The swing arm 6 can be made to swing around the first support shaft 5 by rotating it by a drive gear (not shown).

In addition, by using toothed wheels such as sprocket wheels for the first transmission wheel 11 and the second transmission wheel 12, and by using a chain, timing belt, etc. as the endless rotating body 13 for transmission, accuracy can be achieved without slipping. transmission can be performed. Further, the torch support 8 is configured so that the torch 9 held thereon is inclined at 45 degrees with respect to the imaginary line connecting the welding point 10 and the second support shaft 7, but this angle is not particularly limited.

In addition, when hanging the endless rotating body 13 for transmission,
For example, as shown in Figure 2, the torch tip welding point 1
0 is located on the perpendicular line 18 passing through the center of the first support shaft 5, the swinging arm 6 is swung relative to the main body 4, and the torch support 8 is swung relative to the swinging arm 6. put.

According to the torch holding device 3 configured as described above, as shown in FIGS. 2 to 5, the means 14
When the swinging arm 6 is swung around the first support shaft 5, the first transmission wheel 11 is fixed to the main body 4, and the second transmission wheel 12 is half the diameter of the first transmission wheel 11. The swinging arm 6
As the second transmission wheel 12 swings, the swing arm 6
It is rotated with respect to the swing arm 6 by the endless rotating body 13 for transmission in a direction opposite to the swing direction of the swing arm 6 and by the same angle as the swing angle of the swing arm 6. The rotation of the second transmission wheel 12 is transmitted to the torch support 8 via the second support shaft 7, so that the angle of the torch 9 supported by the torch support 8 with respect to the horizontal plane is on the vertical two-dimensional plane. will change continuously. Moreover, at this time, the tip welding point 10 of the torch 9 is always located on the perpendicular line 18.

Fig. 2 shows the torch 9 inclined at an angle (15°) suitable for vertical fillet welding with respect to the horizontal plane, and Fig. 4 shows the torch 9 inclined with respect to the horizontal plane for horizontal fillet welding. It is shown tilted at a suitable angle (45°). FIG. 5 also shows a state in which the swinging arm 6 is swung to the opposite side of the perpendicular line 18, and the torch 9 is inclined with respect to a horizontal plane at an angle (75°) suitable for horizontal butt welding.

The torch holding device of the present invention can be implemented and used as in the above embodiment, and the inclination angle of the torch support is changed while the tip welding point is always located on a constant imaginary vertical line. In particular, according to the structure of the present invention, the number of parts and fulcrums are smaller than in the conventional parallel link system, so it is less likely to play and has excellent durability.
The posture of the torch can always be changed with high precision. Moreover, compared to the conventional swing-rotation method, the
It has the effect of being able to continuously change the angle of the torch along the dimensional plane, and can be used extremely effectively as a torch holding device for automatic welding machines.

[Brief explanation of drawings]

Figure 1 is a perspective view of the entire device in use, Figure 2
4 and 5 are side views of main parts in different operating states, and FIG. 3 is a vertical sectional side view of FIG. 2. DESCRIPTION OF SYMBOLS 1... Welding robot main body, 2... Robot hand that can be raised and lowered, 3... Torch holding device of the present invention, 4... Main body, 5... First support shaft, 6... Swinging arm, 7... Second support shaft, 8...Torch support, 9
... Torch, 10 ... Welding point, 11 ... First transmission wheel, 12 ... Second transmission wheel, 13 ... Endless rotating body for transmission, 14 ... Swinging arm drive means.

Claims (1)

[Claims] 1 A swinging arm that is swingably supported on the main body around a first support shaft, and a swing arm that is swingably supported around a second support shaft that is parallel to the first support shaft at the tip of this swing arm. a first transmission wheel fixed to the main body concentrically with respect to the first support shaft; and a second transmission wheel fixed to the torch support concentrically with respect to the second support shaft. An endless rotating body for transmission is hung on the transmission wheel, and means is provided for swinging the swinging arm with respect to the main body, and when the swinging arm is swung by this means, it is held by the torch support. The distance between the welding point at the tip of the torch and the second support shaft, and the first support shaft such that the angle of the torch changes while the welding point at the tip of the torch is always located on a constant imaginary line. A torch holding device for an automatic welding machine, the torch holding device for an automatic welding machine comprising setting a ratio between the distance between the first transmission wheel and the second support shaft, and a transmission ratio between the first transmission wheel and the second transmission wheel.