JPS58176084A - Welding robot - Google Patents

Abstract

PURPOSE:To extend the allowable welding range, and to reduce the number of robots to be installed and the number of welding machines to be equipped, by mounting plural welding guns at varying angles to the movable forward end of one unit of welding robot. CONSTITUTION:Five shafts; a traversing shaft 6a which moves in a direction F, a vertical shaft 6b which moves in a direction G orthogonally therewith, a horizontal shaft 6c which moves in a direction H orthogonally with the shaft 6b, a shaft 6d which rotates in an arrow I direction with respect to the shaft 6f offset 90 deg. in the axial direction of the shaft 6c, and a shaft 6e which rotates in an arrow J direction with respect to the shaft 6g orthogonal with the shaft 6f, are mounted to the movable forward end of a welding robot 6. The positions of welding guns 2, 3 mounted to the shaft 6e are controlled with the orthogonal 3 shafts of the shafts 6a, 6b, 6c, and the attitude of the welding gun is controlled with the remaining shafts 6d, 6e, whereby the automatic welding in all ranges is made possible with one unit of the welding robot, and the number of robots is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a welding robot suitable as an automatic welding device used, for example, in a car body assembly line.

For example, as shown in FIG. 1, when parts of the rear end panel 1 at the rear of the vehicle body, surrounded by broken lines A and B', are brought into contact with the spora l on the same assembly line, the respective parts A and B (
Part A is the attachment of the batch to the rear end panel upper part 9 Part B is the rear end panel lower, the joint between the upper and floor panel , it is best to weld by placing two movable welding guns along the flange of the rear entrance nozzle 1. On the other hand, for location B, use the X type welding gun 6 to move the yoke electrode of the welding gun 6 into the hole. Since it is necessary to weld while entering the inside of the robot, welding guns 2 and 3 are placed in separate processes on the assembly line.
, 5 are attached to the tip ends 4a, 5a of the movable parts as shown in the figure.

Alternatively, although not shown in the drawings, it is possible to place several types of dedicated welding equipment (multi-bath welding equipment) in the entire assembly line instead of robots and weld parts A and l1l in one process, but this is not versatile. It becomes an assembly line.

Therefore, considering the versatility, the form t as shown in Fig.
Although it is inevitable, the number of robots will increase, which will not only make the assembly line expensive but also require space for the robots.

This invention was made in view of the above-mentioned points, and there is a problem in that a plurality of welding guns are all attached at different angles to each other at the tip of a movable part in one robot. The aim is to provide all welding robots that are installed differently to solve all the conventional problems.

In other words, by attaching multiple welding guns (of the same type or different types) to one robot, and by making the mounting angle brackets for each welding gun the same, the welding range of one robot can be widened, and it is possible to By making it possible to weld workpieces in the welding area, the number of robots installed can be reduced, allowing robots to be placed on the assembly line without space constraints, and reducing equipment costs. measure.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to FIGS.

FIG. 2 is a block diagram showing an embodiment of the present invention, and parts corresponding to those in FIG. 1 are denoted by the same reference numerals. It is attached.

In the same figure, what is the axis configuration of the movable part of robot 6? Third
As shown in the figure, the LB (traverse) axis 6a moves in the direction of arrow F relative to the base (not shown), and the CLI'I (vertical) axis moves orthogonally to this LB axis 6a in the direction of arrow G. 6bs
and moves orthogonally to this CLH axis 6b in the direction of arrow H<ARM-E (horizontal) axis 6c orthogonal three axes
- The S-axis 6d rotates in the direction of the arrow 1 with respect to the axis 6f offset by 9oo as shown in the figure with respect to the axial direction of the E-axis 6c.
and a θ-axis 6e rotating in the direction of arrow J with respect to an axis 6g orthogonal to the axis 6f.

Note that this robot 6 has an LB axis 6a, a CLH axis 6b,
The three orthogonal axes of the ARM-E axis 6c perform all position control of the welding gun attached to the θ axis 6e, and the remaining nine S axes 6
The posture of the welding gun is entirely controlled by the d and θ axes 6e.

On the mounting surface of the θ-axis 6e at the tip of the robot 6, a fourth
A gun bracket 7 having a body mounting board 7a and two gun mounting boards 7b and 7c as shown in FIGS. What are the mounting angles for welding gun 1 and gun mounting board 7c for all X type welding guns 3? They are installed at a 90° angle from each other.

The welding control systems of these C type and X type welding guns 2 and 3 are as follows.

First, the current control system that controls the current value and energization time of the welding current consists of a timer 8° and a welding transformer 9, as shown in Fig. 2.
The secondary cable 1o is the same as the well-known one and has one system, and the two systems of secondary cables 11a and 11 are connected via a changeover switch (not shown) at the tip of the secondary cable 1°.
b, and the current of the welding gun 2.3 is controlled via these secondary cables 11a and 11bk.

Also, a cylinder 2a that controls the pressurizing force of the welding gun 2.3.
, 3a, the welding gun 2.3 is in an open state due to the biasing force of the spring? If it is of the maintenance type, it will be as shown in Figure 7.

That is, welding gases /2 and 3 are both springs 2a and 2.
The biasing force b causes the valve to be in the open state as shown in the figure, and in this state, for example, the solenoid 12a of the double-ended solenoid valve 12 is energized by the X type gun selection signal, and the spring offset type single-side solenoid valve 16 (in the state shown When the solenoid 13a, which is in a non-energized state, is energized by the pressure signal, the cylinder 3 of the welding gun 3
Since air pressure is supplied to the chamber R at a, the X type welding gun 6 closes in response to the pressurization signal.

At this time, since air pressure is not supplied to the cylinder 2a of the C type welding gun 2, the welding gun 2 is in an open state due to the biasing force of the spring 2b.

Similarly, if it is desired to operate the C-type welding gun 2, the solenoid 12b of the double-end solenoid valve 12 is energized by the C-type gun selection signal, and the solenoid 14a of the one-side solenoid pulp 14 is energized by the pressure signal.

By the way, is this a normal type welding gun without a spring? When used, two valves for maintaining the gun open state may be added to each pneumatic circuit shown in FIG.

Next, how will the robot 6 operate when the welding robot 6 configured as described above welds all parts of the rear entrance nozzle 1 at the rear of the vehicle body shown in FIG. 2? Figures 8 to 1
This will be explained with reference to zero drawing money.

In addition, in FIGS. 8 to 10, illustrations of the secondary cables 11a, 11b, etc. shown in FIG. 2 are omitted.

In addition, in the following explanation, "to perform welding" means to energize either the welding gun 2 or 6 at the welding point position, and to use the pneumatic circuit for controlling the cylinder of the welding gun shown in FIG. This represents a state in which either the welding gun 2 or the cylinder 2a or 5ak at the burn point 9 is activated.

First, when welding the welding area on the rear end panel 1 shown in FIG.
The shaft 6b and the ARM-E shaft 6c (hereinafter abbreviated as these three axes? Orthogonal three axes 6a, 6b, 6c) are respectively driven and controlled so that the θ-axis 6e is positioned above the rear end panel 1 as shown in FIG. 8, and swing the C type welding gun 2 downward to the position shown in FIG.
Two tips for welding gun 2? Position it at the welding point.

And welding at that spot position? After this, the three orthogonal axes 6al, 6bl, and 6Ck of the robot 6 are controlled to move the welding gun 2 to the next welding point position in the welding area, and complete welding at that welding point position.

After repeating all of the above operations to complete welding of all the welding parts, the welding gun 2 is returned to the position shown in FIG. 2.

Next, when welding the welding area A't- on the rear end panel 1 shown in FIG. In addition to doing so,
After the θ-axis 6ekW is rotated 180° to the right as shown in FIG. 9, the two tips of the C type welding gun 2 are positioned at the welding points on the periphery of the lamp hole 1a of the rear end panel 1.

Then, the above-mentioned orthogonal three axes 6a, 6b, 6c and the θ axis 6e
Welding at each dot position around the entire periphery of the lamp hole while intermittently moving a predetermined amount? Let's do it.

In this way, welding of welding part A? When everything is finished,
Return the welding gun 2 to its position as shown in FIG.

In addition, when welding the welding area Bi in the rear end panel 1 shown in FIG.
, 6ck, respectively, so that the θ-axis 6e is located near the bottom of the rear end panel 1 as shown in FIG. 10, and the S-axis 6d is rotated to the right by a predetermined amount from the state shown in FIG. 2. By, X type welding gun 3kM10
As shown in the figure, swing the welding gun 60 upward to position the two tips of the welding gun 60 at the welding point B.

After welding at that welding point position, the three orthogonal axes 6al, 6bl, 6C'c of the robot 6 are driven and controlled to move the welding gun 6 to the next welding point position in the welding area B. Welding is carried out at 0. Then, after repeating all of the above operations and completing the welding session at welding area B, the welding gun 6 is returned to its position as shown in FIG.

When welding the welding part B, in addition to the gun posture shown in FIG. 10, after rotating the θ-axis 6e'c 180 degrees to the right or left from the state shown in FIG. Alternatively, the welding gun 3 may be swung downward.

Furthermore, the motion of each axis in the robot 6 is a playback motion based on data stored during teaching.

Furthermore, as a robot for attaching the welding guns 2 and 6, in addition to the robots having the configurations shown in FIGS. 2 and 6, for example, a horse-riding p-type robot (5
An articulated robot (5 axes) 6 as shown in FIG. 12 is conceivable.

The effects of the above-described embodiments include simplification of robot layout on the assembly line and reduction of equipment costs by assigning two different types of welding gun sounds to one robot. However, the effect when a plurality of welding guns of the same type are attached to one robot at different angles will be explained with reference to FIGS. 16 and 14.

FIG. 16 shows two X-type welding guns 3 attached to the θ-axis 6e of the robot 6 shown in FIGS. 2 and 6 via a gun bracket 15' at different mounting angles of 90 degrees from each other. It is a partial perspective view showing the situation.

If this is done, for example, the angle at which the S axis 6d and the θ axis 6e can be rotated? If each welding gun 6 is set at 270 degrees, the variable range of the welding point surface of the welding gun 6 is shown by the dashed line, and as shown in FIG. It becomes wider compared to the range.

This means that the robot can move as much as a 6-axis robot with a 5-axis configuration and a 6-axis configuration.

Therefore, it is possible to weld workpieces at any welding location, and due to □ and □', it becomes possible to fully support a hybrid line that simultaneously produces different types of vehicles.

Although we have described an example in which two welding guns of the same type or different types are attached to the tip of the robot's movable part with the installation angles differing by 90 degrees from each other, the present invention is not limited to this. It may be mounted, and the mounting angle is also arbitrary.

Further, in the above embodiment, the welding points are limited to all the rear end panels of the vehicle, but the welding can be performed in the same way to other parts of the vehicle, and the object to be welded is not limited to the vehicle.

As explained above, according to the present invention, not only can a single welding robot be used to weld a wide range of shapes and postures of workpieces at welding locations, but also the number of robots can be reduced compared to conventional methods. Therefore, the robot can be laid out on the assembly line without being restricted by the total space.

[Brief explanation of the drawing]

FIG. 1 is a block diagram for explaining the outline of the structure and operation of a conventional welding robot. FIG. 2 is a block diagram showing an embodiment of the present invention, FIG. 6 is a perspective block diagram of the robot in FIG. 2, and FIGS. 4 to 6 each show an example of the gun bracket in FIG. 2. They are a front view, a side view, and a bottom view. FIG. 7 shows the cylinder 2 of the welding gun 2.6 in FIG.
Pneumatic circuit diagrams for drive control of a, 3a, Figures 8 to 10
11 and 12 are perspective configuration diagrams showing other examples of robots to which this invention is applied, respectively. , FIG. 16, and FIG. 14 are perspective views of essential parts, respectively, for explaining the effect when two of the same type of welding guns are attached to the tip of the movable part of the robot. 1...Rear end panel 2...C type welding gun 6...X type welding gun 4.5.6...Robot 7.15...Gun bracket Figure 3 Figure 4 Figure 7 Sky JE Posting Figure 8 Figure 9

Claims (1)

[Claims] 1) Multiple welding guns were installed at different angles to the tip of the movable part of the 11 robots.t%
A welding robot.