JPS5978786A - Seam welding machine - Google Patents

Abstract

PURPOSE:To deal easily with the change in the shape of a material to be welded and to perform a corrosion-preventive treatment simultaneously with welding by providing detectors which detect the extent of movement of the material to be welded and a treatment means respectively and enabling the treatment means to follow up the displacement of a treatment point. CONSTITUTION:A seam welding machine consists of the 1st detector which outputs the signal for the position of a material 12 to be welded, a treatment means, the 2nd detector which detects the extent of movement thereof, and a control device 27. The above-described 1st detector detects the rotation of electrode wheels 10, 11, which rotate while sandwiching the material 12, as the extent of movement of the material 12. The treatment means (for example, a torch nozzle 17) is moved back and forth near the welding point 16 by the wheels 10, 11 toward the point 30 to be treated, by a driving device 19. The device 27, connected to the 1st and 2nd detectors, has the function to store the signal from the 1st detector and the command function to operate the device 10 in accordance with the storage signal.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a seam welding machine for welding plated m-plates such as fuel tanks, and particularly to a seam welding machine configured to carry out corrosion prevention treatment of welded parts at the same time as welding.
11.

For example, a known method for manufacturing a fuel tank made of plated steel is to assemble two parts, the upper and lower parts press-formed into a predetermined shape, and then seam weld the flange part. Due to pressure, the plating may peel off, and a conventional repair method is known in which the welding surface from which the plating layer has peeled off is heated and the plating layer near the weld is re-welded. When performing such repairs, it is best to carry out the welding work after the weld has cooled down.
Since the amount of heat required for heating increases, it is preferable to utilize residual heat from seam welding, and it is also desirable to perform the rB bonding process automatically.

C. A method that satisfies these requirements is a method in which a heat treatment tool such as a torch nozzle is placed near the welding point, and the welding line is continuously heated by the torch nozzle to heat-weld the plated foil that has peeled off during welding. is possible. In this case, it is necessary to place the heat treatment tool at a location away from the welding point to avoid interference with the electrode and the torch nozzle. Therefore, when heat treating a welded part using such a device, if it is a straight part, the relative position of the heat treatment tool and the electrode can be fixed and no particular problem will occur, but if it is a curved part, there will be no particular problem. The heat treatment tool must be moved to follow the movement of the weld zone because of the large movement of the weld zone.

That is, FIG. 1 is a schematic diagram showing the situation in which seam welding of a fuel tank is being performed. By rotating the electrode wheel 1 and performing welding continuously, the workpiece 2 to be welded moves, and as a result, the welding point 3 reaches a part of the corner of the material to be welded 2,
Part of the corner is welded by rotating the material to be welded 2 around the welding point 3. Therefore, if the torch nozzle 4 for re-welding the peeled plated foil is placed ahead of the welding point 3 in the moving direction of the welded material 2, the torch nozzle 4 will move as the welded material 2 rotates.
The torch nozzle 4 needs to be advanced significantly to follow the displacement of the processing point 5, and after welding a part of the corner is completed, the torch nozzle 4 needs to be retreated to its previous position.

Various configurations have been considered for the TL structure for moving the heat treatment tool such as the 1-1 nozzle as described above, but none of them have been fully satisfactory and each has its own drawbacks. In other words, in the case of a mechanism that uses a cam that matches the shape of the product and uses that cam to move the heat treatment tool to follow the welding line of the product, the i side of the cam etc. must also be changed each time the shape of the product is changed. Therefore, it is difficult to easily adapt to changes in the shape of the product, and there are problems such as lack of versatility. In addition, in a mechanism in which the welding line is detected by an appropriate detector and the heat treatment tool is moved to follow the movement of the welding line based on the output signal, when an oxygen acetylene flame 1--chi etc. is used as the heat treatment tool, the In order to avoid bad stomach effects caused by tingling and the heat of the heat treatment tool,
The detector must be placed far away from the processing point,
Therefore, it is difficult to accurately detect the weld line,
Furthermore, since it is also necessary to correct the relative displacement between the detector, the welding point, and the heat treatment tool, the control system and the control system become extremely complicated, which results in an increase in cost. Furthermore, in a mechanism in which parts of the product other than the parts to be welded, such as a standing wall in the case of a fuel tank, are I-laced by appropriate means and the heat treatment tool is moved according to the shape, the parts to be welded, such as the standing wall, etc. Part 1: The shape of the lace part may not always match perfectly, so
There are problems such as difficulty in aligning the heat treatment tool accurately with the weld line.

The present invention was made in view of the above circumstances, and an object of the present invention is to provide a seam welding machine that has a simple configuration and can move processing tools such as a torch nozzle accurately along the welding line. The features include a first detector that detects the rotational speed of the N contact wheel that rotates while pinching the material to be welded as the amount of movement of the material to be welded, and a drive device that moves back and forth toward the material to be welded. The processing tool has a processing tool that is moved, a second detector that detects the amount of movement of the processing tool, and a control device to which each of the detectors is connected, and which corresponds to the device signal constituted by the first detector. The present invention is characterized in that a control device stores a signal that causes the horn to enter from a second detector, and operates the drive device based on the stored signal to move the processing tool to follow the welding line. .

Embodiments of the present invention will be described below with reference to FIGS. 2 to 5.

FIG. 2 is a schematic exploded perspective view showing an embodiment of the present invention, in which an upper electrode ring 10 and a lower electrode ring 11 rotate about mutually parallel axes, and by these two, the material to be welded is The electrode driving knurl 13 is arranged in contact with the outer periphery of the upper electrode 10, and the first electrode driving knurl 13 is connected to the electrode driving knurl 13. A detector, for example a rotary encoder 14, is connected via a roller 15. In other words, the material to be welded 12 is fed by rotating each electrode ring 10.11, and at the same time the rotary encoder 14 rotates and outputs a pulse signal, so that the rotary encoder 14 can detect the welding point 16 where welding is currently being performed. The position from a predetermined welding start point is detected.

On the other hand, a torch nozzle 17 as a processing tool is arranged toward the welding 1118 on the front side in the feeding direction of the welding object 412 with respect to the welding point 16 formed by each electrode wheel 10.11, and the torch nozzle 17 is connected to the drive device 19. It is designed to be moved back and forth toward the welding pedestal 18. That is, the drive device 19 includes a drive motor 20 such as a DC motor,
Feed screw shaft 21 rotated by its drive motor 20
A movable block is screwed onto the feed screw shaft 21 and moves back and forth along the guide 22 as the feed screw shaft 21 rotates.
1 nozzle 1
7 is attached to the moving block 23 via a bracket 24.

Furthermore, as a second detector for detecting the movement R of the torch nozzle 17, a linear scale 25 on which a magnetic signal is recorded, for example, is arranged parallel to the moving direction of the moving block 23, and reads the magnetic signal to generate a signal. A magnetic head 26 that outputs a signal is integrally attached to the moving block 23.

Further, the rotary encoder 14 and the magnetic head 26
and drive motor 20 are each connected to a control WII device 27, and an operation panel 28 is connected to the control device 1127. The main purpose of the control device 27 is to control the drive motor 20 so that the torch nozzle 17 is always directed toward the welding point 118 during welding, and it receives a so-called welding point position signal N input from a rotary encoder 14h).
The so-called nozzle position stomach signal inputted from the magnetic head 26 @n
and a so-called teaching function that stores the welding point position signal N in correspondence with each other, and outputs a nozzle position signal n corresponding to the welding point position signal N among the stored signals to move the torch nozzle 17 to the desired position. It also has a command function to operate the drive motor 20 to move the motor 20 to . Further, the operation panel 28 is configured to move the i-chi nozzle 17 to an arbitrary position by manually operating the drive motor 20.

In addition, notice number 29 in Figure 2 is a limit switch,
The welding point is turned on and off by a projection (not shown) provided on the workpiece 12 or a jig (not shown) on which the workpiece 12 is placed, and the welding point reaches the corner of the workpiece 12. The point in time and the point in time when corner welding is completed are detected, the detection signal is input to the control device 27, and the control device 27 is operated only when welding a corner portion where it is necessary to move the torch nozzle 17 back and forth. It looks like this.

Next, the operation of the seam welding machine configured as described above will be explained.

First, the contour line to be welded has the shape shown in FIG. ! Suppose it is larger than . When welding under these conditions, an arbitrary point on the straight line of the contour to be welded is determined as the welding start point, and the workpiece 12 is sandwiched between the upper and lower electrode wheels 10.11 at the welding start point. , teach from that state.

In other words, the NWA is
The electrode wheel 10.11 is rotated at low speed via the drive knurl 13, and at the same time the drive motor 20 is operated via the operation panel 28 so that the i-heech nozzle 17 faces the processing point 30. When the welding point 16 reaches the starting point of the first corner I as a result of the rotation of the welding ring 11, the material to be welded 12 is sent, for example, in the direction of the arrow in FIG. is operated, and the material to be welded 12 begins to rotate around a bin (not shown) so that the contour line to be welded passes between each electrode wheel 10.11, and therefore the material to be welded 12
The processing point 30 moves with the rotation.

To explain the situation with reference to FIG. 4 and FIG. 31 (from the point 31 to the point 32 in FIGS. 4 and 5(A)), the processing point 30 becomes 1.- as shown in FIG. 5(A). When the welding point 16 and processing point 30 are both in the corner section, there is no change in their relative positions, and furthermore, the welding point 16 moves forward in the corner section I. After reaching the end point 33, the material to be welded 12 does not rotate and is sent in a straight line. ) then code 3
3 to the point 34), the processing point 30 moves toward its previous position as shown in FIG. 5(A).

Since the processing point 30 is displaced as described above, the drive motor 2
0 through the operation panel 28, the torch nozzle 17 is moved back and forth to follow the movement of the processing point 30. The movement 3'1 degree and the direction in that case are shown in FIG. 5(8).

Rotating the electrode wheels 10 and 11 [movement of the welding point 16 as the material to be welded 12 is fed, i.e., the position of the welding point 16 and movement of the processing point 30 between them, i.e., the 1-1 nozzle 1
The setting position No. 7 is set in the control device 27 by making the welding point position signal N from the rotary encoder 14 and the nozzle position signal n from the magnetic head 26 correspond to each other since the front-distributed mitsu switch 29 has already been operated. is memorized, and the limit switch 29 is operated again when the processing point 30 has passed through the corner part (3).
The operation of the control device 27 is stopped and the input signal is no longer stored.

From then on, each time welding point 16 reaches a corner, do the same as in the above case, and check the position of welding point 16! and torch nozzle 1
7 is determined by the welding point position signal N output from the rotary encoder 14 and the magnetic head 2 by manually moving the torch nozzle 17 as described above.
The two are stored in the control device 27 in correspondence with each other as the nozzle position signal n from 6.

After inputting data for the entire contour line to be welded as described above, that is, after performing teaching,
When welding of the welding material 12 is started from the predetermined welding start point, each time the welding point 16 reaches the course part, the control device 27 changes its position according to the welding point position signal N input from the rotary encoder 14. Nozzle position signal n to drive motor 2
Since the output is made with respect to 0, the 1-1 nozzle 17 is automatically moved and positioned to the same position as the position set during the teaching operation. Therefore, in the above welding machine,
Regardless of the displacement of the processing point 30, the torch nozzle 17 is always kept facing the processing point 30, that is, the welding point 118, and the peeled plated foil is re-welded by performing seam welding.

In other words, in the above-mentioned welding machine, the position to which the 1.-chi nozzle 17 should be moved is stored in advance in the control unit [27] by a teaching operation, and the position to be determined by moving the nozzle 17 is stored in advance in the control unit [27] during actual welding work. 1・-chi nozzle 1
7 can be constantly moved and positioned toward the processing point 30.

In the above embodiment, the rotary encoder 14 as the first detector is rotated by the electrode drive knurl 13 via the roller 15, but the first detector is basically Position the welding point using the electrode wheel 10.
．． As long as the rotary encoder 14 can be detected from the rotation of the electrode wheel 11, the rotary encoder 14 may be directly attached to the electrode drive knurl 13, or the rotary encoder 14 may be directly operated by one of the electrode wheels.

Further, the second detector is not limited to the linear scale 25 and magnetic head 26 shown in the above embodiment, but may be a rotary encoder rotated by the drive motor 20.

Furthermore, the present invention can be used for purposes other than anti-corrosion treatment using the torch nozzle 17. For example, it is also possible to apply an appropriate chemical to the weld line, in which case an appropriate applicator may be used. It may be attached to the movable block 23 in place of the torch nozzle 17 described above, and its installation position may be set to the front or rear side of the welding point 16 in the feeding direction of the material to be welded 12, depending on the fold.

Furthermore, the present invention is not limited to W41-axis control where the processing tool is moved only in the front-back direction, but can also be applied to multi-axis control.

As is clear from the above description, according to the seam welding machine of the present invention, the displacement of the processing point caused by feeding the material to be welded can be
It is stored in correspondence with the position of the welding point on the material to be welded, and based on the stored data -C location F! Since the JR is configured to move by following the displacement of the processing point, when welding workpieces that have a different shape than before, the processing tool can be moved by performing a so-called teaching operation and inputting new data. It is possible to accurately control the position of the material to be welded, and therefore, compared to a device that moves the processing tool using a cam, etc. whose shape corresponds to the shape of the material to be welded, it can easily respond to changes in the shape of the material to be welded. Additionally, since there is no need to replace parts, the number of man-hours can be significantly reduced. Furthermore, since the seam welding machine of the present invention is configured to detect the processing point during teaching using the processing tool, the welding line is detected by a detector attached to the processing tool, and processing is performed based on the detection signal. Compared to conventional devices that control tools, the amount of control data is small, and accordingly, the overall configuration of the device can be made relatively simple and low-order.

Furthermore, since the present invention has a configuration in which the processing point is directly detected, the position of the processing tool can be controlled more accurately compared to a configuration in which the processing tool is positioned by tracing a location other than the weld line on the material to be welded. Effects such as

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram for explaining the displacement of the processing point as the material to be welded is fed, Fig. 2 is a schematic exploded perspective view showing an embodiment of the present invention, and Fig. 3 is an illustration of the contour shape to be welded. A diagram showing an example, FIG. 4 is an enlarged view of one corner of the outline shape,
Figure 5 (A) is a miniature diagram showing the displacement of the processing point due to welding the corner part, and Figure 5 (B) is a scale diagram showing the direction and speed in which the processing tool is moved to follow the displacement of the processing point. Fig. 5 is a diagram corresponding to A>. 10.11... Electrode wheel, 12... Material to be welded, 1
4... Rotary encoder, 16... Welding point, 17... Torch nozzle, 18... Welding line, 1
9... Drive device, 20... Drive motor, 21.
・・Feed screw shaft, 23・・Moving block, 25・
...Linear scale, 26...Magnetic head, 27
...control device, 30 ... processing point, N ... welding point position signal, n ... nozzle position signal. Applicant: Toyota Motor Corporation agent, patent attorney Yutaka 1) Hisashi Take (and one other person) ) Figure 1 Figure 3 Figure 4 Figure 5 (A)

Claims (1)

[Claims] A first detector is provided, which detects the rotation of at least one of the pair of electrode wheels rotating while sandwiching the workpiece to be welded, as a movement m of the workpiece to be welded, and outputs a position signal; In the vicinity of the welding point by each electrode wheel, a processing tool that is moved back and forth toward the point to be processed by a drive device is arranged on the fishing force side or rear side of the welding point in the feeding direction of the welded material. A second detector for detecting the amount of movement of the processing tool is provided, the first detector and the second detector are connected to a single device, and the control device is composed of the first detector. a function of storing a signal input from the second detector in correspondence with a device signal to be inputted, and operating the drive device based on the stored signal to move the processing tool back and forth to follow the welding line. A seam welding machine characterized by having a command function to move the seam welding machine.