JP3594919B2 - Weaving device with automatic welding machine - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a weaving device for weaving a welding torch when performing butt welding or fillet welding using an automatic welding device.
[0002]
[Prior art]
Generally, as an automatic welding device for welding while weaving, a torch holder is mounted on an eccentric wheel mounted on a drive motor to swing the tip of the torch holder. In this case, if the connection position between the eccentric wheel and the torch is not changed, the swing width (weaving width) of the tip of the torch becomes constant, and there is a problem that the weaving width cannot be adjusted. In view of this, there has been provided an apparatus in which the amount of eccentricity of the eccentric wheel is made variable so that the swing width (weaving width) of the tip of the torch can be adjusted.
[0003]
Also, in welding for weaving operation, in order to increase the amount of heat input at both ends of the weaving width and obtain sufficient penetration, weaving operation of the welding torch is temporarily stopped at both ends of the amplitude of the weaving operation. I have to.
[0004]
[Problems to be solved by the invention]
Conventionally, in order to temporarily stop the welding torch at both ends in the width direction of the weaving, the torch is stopped by a mechanical method or an electrical method, but the mechanical method has a complicated structure. Therefore, the weaving device mounted on a trolley or the like has many problems. In addition, the electric method requires a start / stop circuit and a timer circuit for stopping and starting the drive motor that controls the swinging of the torch, and has a problem that the control system becomes complicated.
[0005]
The present invention has been made in view of such a point, and an object of the present invention is to provide a weaving device capable of reliably performing weaving operation with a simple structure and easy electric control. And
[0006]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the present invention transmits a torque of a rotary drive motor to a dog plate via a speed reduction mechanism, and operates a limit switch at a position corresponding to both ends of the amplitude of the welding torch on the peripheral surface of the dog plate. And a limit switch corresponding to the peripheral surface of the dog plate, and the limit switch is applied to the rotation speed control circuit of the rotation drive motor in a state where the rotation speed of the rotation drive motor is reduced when the limit switch is operated. The guide frame is fixed to the dog plate so as to be rotatable with the dog plate, and a slide member is incorporated in the guide frame so as to be linearly movable. A roller is rotatably supported on the slide member, and the roller is swung. The welding torch is supported on the pivot shaft of the swing arm by being inserted into a long hole formed in the arm. .
[0007]
Effect of the Invention
According to the present invention, a dog plate having a limit switch actuating cam on its peripheral surface is arranged in a power transmission system for transmitting the rotational force of the rotary drive motor as the swinging power of the welding torch, and is adapted to correspond to the peripheral surface of the dog plate. Since the arranged limit switch is interposed in the rotation speed control circuit of the rotation drive motor, when the limit switch operation cam operates the limit switch to reduce the rotation speed of the rotation drive motor, the sine curve A welding torch operating with a simple vibration is pseudo stopped at both ends of the amplitude.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION
FIG. 1 shows an embodiment of the present invention, FIG. 1 is a front view showing an example of an automatic welding machine, FIG. 2 is a side view of a weaving device taken out, and FIG.
The weaving device (1) is mounted on a trolley (2) that can travel straight, together with a traveling drive device (3), and supports a welding torch (4) in a swingable manner.
[0009]
In this weaving device (1), a slide plate (6) is mounted on a slide frame (5) so as to be linearly movable, and a dog plate (7) is mounted on the surface of the slide plate (6). A pair of limit switch actuating cams (8) are formed to protrude from the peripheral side surface of (7). A limit switch (9) is fixed to the sliding plate (6) so as to face the peripheral side surface of the dog plate (7). The sliding plate (6) is configured to be adjustable in and out of the slide frame (5) with a guide rod (10) and an adjusting screw (11). The displacement of the dog plate (7) from the rotation axis can be finely adjusted.
[0010]
Further, a guide frame (12) is fixed to the dog plate (7) so as to be rotatable along with the dog plate (7), and a slide member (13) is attached to the guide frame (12) by rotating the adjusting screw (14). It is incorporated so that it can move linearly with it. A shaft (15) protrudes from the slide member (13), and a roller (16) composed of a bearing or the like is fitted and fixed to the shaft (15). In this case, one end of the moving range of the slide member (13) is set at a position where the axis of the shaft (15) projecting from the slide member (13) coincides with the rotation axis of the dog plate (7). is there.
[0011]
A support shaft (17) of the welding torch (4) is swingably mounted on the slide frame (5), and a swing arm (18) is fixed to the support shaft (17). The roller (16) projecting from the slide member (13) is fitted in the elongated groove (19) formed in the moving arm (18). The welding torch (4) is securely held on the support shaft (17) via the clamper (20).
[0012]
In the weaving device (1) having such a configuration, the rotational force of the rotary drive motor (not shown) is transmitted to the dog plate (7) via the speed reduction mechanism. The roller (16) protruding from the slide member (13) is moved by the sliding operation of the slide member (13) by the rotation of the adjustment screw (14) mounted on the guide frame (12). Is set at a position eccentric from the rotation center of the dog plate (7), and the rotation of the dog plate (7) causes the swing arm (18) to swing about the support shaft (17) as the swing center. I do. At this time, since the swing arm (18) is fixed to the support shaft (17), the support shaft (17) swings along with the swing arm (18), and the welding torch (4) swings. Will be. By changing the amount of movement of the slide member (13), the amplitude of the welding torch (4) is adjusted.
[0013]
The limit switch (9) disposed opposite to the peripheral surface of the dog plate (7) is interposed in the weaving speed adjustment circuit of the weaving rotary drive motor, and is formed on the peripheral surface of the dog plate (7). When the limit switch actuating cam (8) operates the limit switch (9), the rotation speed of the weaving rotary drive motor is reduced, and the limit switch actuating cam (8) is moved to the limit switch (9). When is not operated, the rotary drive motor is rotated at a speed corresponding to a preset weaving speed. In this case, when the welding torch (4) is positioned at both ends of the amplitude, the limit switch actuating cam (8) and the limit switch actuating cam (8) or the limit switch actuate the limit switch (9). A switch (9) is arranged.
[0014]
In the weaving device having the above configuration, when the welding torch (4) is positioned at both ends of the amplitude, the limit switch (9) operates to reduce the rotation speed of the rotary drive motor. Because the welding torch (4) oscillating by a simple vibration, the moving speed per unit time is reduced at both ends of the amplitude where the moving direction is reversed, and the driving speed itself is also reduced. , The welding torch (4) is in a pseudo stopped state. As a result, the amount of heat input at both end portions of the weaving width can be increased, and reliable penetration can be obtained. The pseudo stop time is adjusted by the length of the limit switch operating cam (8). In this case, since the rotation drive motor for weaving operation continues to rotate, a control circuit can be simplified without the need for a motor stop circuit or a timer circuit.
[0015]
In the above embodiment, the drive speed is reduced at both ends of the amplitude. However, the drive speed may be reduced also at the swing center portion. In addition, this weaving device can be applied not only to butt welding but also to fillet welding.
[0016]
【The invention's effect】
According to the present invention, a dog plate having a limit switch actuating cam at a position corresponding to both ends of the amplitude of the welding torch on the peripheral surface is arranged in a power transmission system that transmits the rotational force of the rotary drive motor as the swinging power of the welding torch. Since the limit switch corresponding to the peripheral surface of the dog plate is interposed in the rotation speed control circuit of the rotary drive motor, the limit switch actuating cam activates the limit switch, so that the rotary drive motor is driven. When the rotational speed of the welding torch is reduced, the welding torch operating with a simple vibration that draws a sine curve enters a pseudo stop state at both ends of the amplitude. As a result, it is possible to suppress the occurrence of welding defects such as undercuts that can sufficiently obtain penetration at both end portions of the weaving width.
[0017]
Furthermore, since the mechanism for extending the torch residence time at both ends of the weaving width is only the dog plate and the limit switch interposed in the speed adjustment circuit of the rotary drive motor, the structure is simple and special. The control portion of the weaving device that does not require electrical control can be formed compact, and the weaving device can be formed small.
[Brief description of the drawings]
FIG. 1 is a front view showing an example of an automatic welding machine.
FIG. 2 is a side view of the weaving device taken out.
FIG. 3 is an exploded perspective view showing a main part of the weaving device.
[Explanation of symbols]
4 welding torch, 7 dog plate, 8 limit switch actuating cam, 9 limit switch, 12 guide frame, 13 slide member, 16 roller, 17 swing arm, 18 swing arm, 19 ... a long hole.

Claims (1)

A weaving device for weaving a welding torch of an automatic welding machine,
The rotational force of the rotary drive motor is transmitted to the dog plate (7) via a speed reduction mechanism, and the limit switch actuating cam (8) is provided at least at positions corresponding to both ends of the amplitude of the welding torch on the peripheral surface of the dog plate (7). And a limit switch (9) is arranged corresponding to the peripheral surface of the dog plate (7). When the limit switch (9) is operated, the rotation of the rotation drive motor is reduced. The guide frame (12) is fixed to the dog plate (7) so as to be able to rotate together with it, and the slide member (13) is incorporated in the guide frame (12) in a state that allows linear movement. A roller (16) is rotatably supported by the slide member (13), and the roller (16) is inserted into a long hole (19) formed in the swing arm (18), and the swing arm (18) Supports welding torch (4) on fulcrum shaft (17) Weaving device in an automatic welding machine, characterized in that allowed.

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