JPH08141952A - Position correcting device in robot system - Google Patents

Abstract

PURPOSE: To improve weld quality by correcting the position of a weld robot accurately by only sensing a handling robot. CONSTITUTION: Weld is performed quickly without any needless movement and also weld quality is improved by mounting a holding device for an object to be welded 4 in a handling robot 1 and measuring simultaneous sensing actuation/transfer amount and comparing them and feeding back to a weld robot 2 such that transfer amount of the weld robot 2 when it is sensed by a detector 5 of a floating becomes equivalent to transfer amount 10 of the handling robot 1 and performing accurate position compensation at a welding position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to robot position correction for a welding robot system.

[0002]

2. Description of the Related Art In recent years, welding robot systems have been able to automate welding by the position correction function of the robot even if there are variations in the objects to be welded.

An apparatus for transporting an object to be welded by a conventional handling robot and welding it by the welding robot will be described below.

FIG. 3 shows the configuration and actual operation of the conventional position correction. In FIG. 3, reference numeral 1 denotes a handling robot, which has a device 3 for holding an object 7 to be welded, a device 4 for floating the holding device 3, and a detector 5 for detecting a floating overrun.
Is composed. 2 is a welding robot, and a welding torch 6
Hold and weld. Reference numeral 9 denotes a holding table for the object to be welded, which holds the object to be welded 8 having variations.

The operation of the apparatus configured as described above for performing position correction will be described below.

First, the handling robot 1 is operated to a position where the floating overrun detection does not occur, 11 is operated to the actual welded position, and it is stopped and 11 to the reference position and the actual 10 are operated. Correct the difference B. Next, the welding robot 2 senses the objects 8 to be welded, corrects the difference B between the reference position 12 and the actual 13, and welds the objects 7 and 8 together.

[0007]

However, in the above-mentioned conventional configuration, the differences A and B from the reference position are not the same if the workpiece 8 is bent. Welding robot 2 first
When the welding position is sensed by, the position changes when welding is performed due to the deflection of the workpiece 8 when it is pressed against the workpiece 8 by the handling robot 1 in a floating manner, so the welding gap deviates and the welding quality is secured. Can not. In addition, there is a problem in that the sensing operation for position correction of the handling robot and the welding robot becomes a series, and the operation time becomes long.

The present invention solves the above-mentioned conventional problems by sensing the handling robot and the welding robot at the same time to detect the sensing position of the handling robot,
That is, an object of the present invention is to improve the welding quality by correcting the position difference between the reference position and the actual position at the welding position by the welding robot so that the position can be corrected quickly and accurately.

[0009]

A welding robot holding a workpiece, a welding robot holding a torch, a moving amount of the handling robot and a moving amount of the welding robot are compared, and the moving amount of the welding robot is compared. Is provided so as to be the same as the movement amount of the handling robot.

Further, a handling robot that holds the object to be welded, a welding robot that holds the torch, and a calculating means for calculating a difference between a reference value as a movement target of the handling robot and an actually moved movement amount as a correction value. And a control means for moving the welding robot by adding the correction value to a reference value which is a movement target of the welding robot.

[0011]

With the above configuration, the movement amount of the welding robot also changes according to the movement amount and the change amount of the handling robot, so that the position of the welding robot can be adjusted only by the sensing of the handling robot.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 is a handling robot, which comprises a holding device 3 for holding an object 7 to be welded, a device 4 for floating the holding device 3, and a detector 5 for detecting the floating. . A welding robot 2 holds a welding torch 6 to perform welding. In addition to this, the control device is configured to perform position correction. In FIG. 1, X is the reference position of the welding robot 2, Y is the reference position of the handling robot 1, and the difference between the reference positions is the difference between the initial welding robot 2 and the handling robot 1 and is corrected by teaching. It is supposed to be done.

The operation of the position correcting device configured as described above will be described with reference to FIG.

First, a sensing command is simultaneously issued to the handling robot 1 and the welding robot 2. The handling robot 1 presses the object to be welded 7 in FIG. 1 against the object to be welded 8 to float, and the floating detector 5 is turned on and stopped. At the same time when the detector 5 is turned on, the welding robot 2
To issue a stop command to stop the welding robot 2. At this time, the movement amounts of the handling robot 1 and the welding robot 2 are measured, the two are compared, the difference is fed back to the welding robot 2, and the two are controlled to have the same movement amount, whereby the position correction is performed. To do. In the embodiment, this position correction is performed so that the movement amount of the welding robot 2 matches the movement amount of the handling robot 1.

The actual movement will be described with reference to FIG. First, when the workpiece 8 is displaced by the dimension A, the handling robot 1 moves 11 and stops. The welding robot 2 is controlled to move by the same amount as this moving amount and then stopped. Therefore, the position 12 at which the welding robot 2 stops and actually welds becomes the same as the reference value, and this value becomes the position where welding is performed.

As is clear from the above, the position correcting apparatus according to the present embodiment enables the welding robot 2 to correct the position at the welding position by sensing the actual object to be welded by the handling robot 1 alone. Therefore, the weldability of the object to be welded becomes constant, the welding quality can be improved, and there is no time loss due to simultaneous sensing, which is an excellent effect.

Although the welding robot 2 is one in the embodiment of FIG. 1, it may be plural. Needless to say, the movement amount measurement in FIG. 2 need not be corrected by comparison if the movement amounts are adjusted to be the same by adjusting the speed of the robot.

Further, in the above embodiment, the reference value Y of movement of the handling robot 1 is compared with the actually moved position, and the difference A is sent to the movement amount of the welding robot 2 as a correction value, and the welding robot 2 is moved. It is also possible to synchronize the positions of both robots by adding the correction to the reference value X of movement and performing correction.

[0020]

As described above, according to the present invention, the movement amount of the handling robot is made equal to the movement amount of the welding robot, the position of the handling robot is corrected, and the correction value is used as a reference for the welding robot. By adding it to the value, it becomes possible to correct the positions of both robots by one sensing.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a correction device according to an embodiment of the present invention.

FIG. 2 is an operation explanatory diagram in one embodiment of the present invention.

FIG. 3 is a block diagram of a conventional correction device

[Explanation of symbols]

 1 Handling robot 2 Welding robot 3 Welding object holding device 5 Floating detector of holding device 7,8 Welding object

Claims (3)

[Claims] 1. A handling robot that holds an object to be welded, a welding robot that holds a torch, a moving amount of the handling robot, and a moving amount of the welding robot are compared, and the moving amount of the welding robot is compared to the handling robot. A position correction device for a robot system, which is provided with a correction means for correcting the movement amount to be the same as the movement amount. 2. A handling robot that holds a workpiece, a welding robot that holds a torch, and a calculation unit that calculates a difference between a reference value as a movement target of the handling robot and an actually moved movement amount as a correction value. And a control means for moving the welding robot by adding the correction value to a reference value which is a movement target of the welding robot, and a position correction device for a robot system. 3. A system for holding an object to be welded by a handling robot in a system in which a handling robot holds an object to be welded, conveys and positions it at a welding position, and performs welding by another one or a plurality of welding robots. And a device that floats the entire holding device, a detector that confirms that the device is floating, and a handling robot that moves the handling robot from a point where there is basic teaching to move the workpiece to the welding position and the floating device floats. Confirm that that the difference between the position detected by the detector and the target point is corrected by the handling robot, the controller that operates the welding robot in synchronization with a certain point of the handling robot, and the handling by the welding robot Stops when receiving a detection signal from the robot's floating detector The welding robot includes a control device for controlling the welding robot and a control device for performing a comparison calculation so that the movement amount of the handling robot from a certain point to a position where it detects that the handling robot has floated and the movement amount of the welding robot are the same. Control so that the difference from the target point of the welding robot is the same as the difference from the target point of the handling robot, and the welding robot does not actually sense the difference from the same target point A position correction device for a robot system, which is characterized in that the position is corrected by sensing.