JPH0630803B2 - Welding line copying device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a welding line copying apparatus in an automatic welding machine.

[Prior Art] The movement trajectory of the welding torch in each welding pass in the groove that requires automatic multi-layer welding has an important influence on the welding quality.
Therefore, it is necessary to control the welding torch to always be held at the optimum position with respect to the welding line, and there is a welding line copying apparatus that obtains information for the control.

This welding line copying device detects the welding line by reciprocating in the width direction in the groove prior to the welding torch.

A copying apparatus of this type is conventionally shown in FIG.

In the drawing, 1 is a material to be welded, 2 is a welding carriage that travels along a welding line 3, 4 is a welding torch, and a copying device 5 is provided in front of the welding torch 4.

X- screwed to screw 7 driven by motor 6
A Z-unit 9 is provided on the slider 8, a screw 11 driven by a motor 10 is provided on the Z unit 9, and a Z-slider 12 is screwed onto the screw 11. An arm 13 is projected from the Z-slider 12 and
A sensor head 14 is provided at the lower end of 13. The sensor head 14 is provided with a stylus (not shown) extending downward, and the motors 6 and 10 drive the X-slider 8 and the Z-slider 12 respectively.
Is moved appropriately, the stylus is the bottom surface of the groove 15, the bead surface,
The shape of the groove and the welding line are detected by contacting the side surface of the groove.

In the figure, X indicates the groove width direction, Y indicates the traveling direction, and Z indicates the vertical direction.

[Problems to be Solved by the Invention] However, in the above-described conventional copying apparatus, backlash between the slider and the screw is unavoidable. Therefore, this backlash appears as a detection error and the detection accuracy is not good. It has become a thing.

In order to solve such a problem, the present invention provides a welding line copying apparatus that is mechanically free of backlash, and seeks to improve the copying accuracy and thus the welding quality.

[Means for Solving the Problems] In the present invention, a slide block is slidably provided in a welding carriage in a groove width direction, and a Z-slider is slidably provided on a column erected on the slide block. The wire, one end of which is attached to the pulley provided on the rotating shaft of the first motor, is fixed to the Z-slider so that a required tension is generated on the wire.
The slider is urged by a spring, the X-slider is slidably provided on the Z-slider in the groove width direction, and the wire attached to one end of the X-slider is attached to a pulley provided on the rotary shaft of another motor. The X-slider is fixed to the slider, the spring is biased by a spring so as to generate tension on the wire, and a stylus is provided at the lower end of an arm hung vertically on the X-slider.

[Operation] Both the Z-slider and the X-slider are driven through pulleys and wires, and the wires have a required tension due to the springs, so that there is no backlash in the process of transmitting the rotation of the motor to the sliders. Accurately grasp the movement of the stylus.

Embodiments Embodiments of the present invention will be described below with reference to the drawings.

A holding block 16 is fixed to the carriage 2, and a slide block 17 is fitted into the holding block 16 so as to be slidable in the X direction. A rack 18 is attached to one side surface of the slide block 17, and is engaged with a pinion 19 rotatably provided on the holding block 16. The rotary shaft 20 of the pinion 19 is projected upward, and the knob 21 is fixed to the upper end of the rotary shaft 20. 22 is a slide block
17 lock bolts.

A column 23 is erected at the tip of the slide block 17
23 is provided with a slide guide 24, and the slide guide 24 has a Z
-Slider 12 is slidably fitted. A stepping motor 25 is attached to the upper end of the column 23, and a pulley 26 is fitted on the rotation shaft of the motor to fasten one end of the wire 27. The wire 27 is hooked around a guide roller 28 and hung down to be attached to the upper end position of the Z-slider 12. Further, a spring 29 is provided so as to extend between the required position of the Z-slider 12 and the slide block 17 to urge the Z-slider 12 downward.

The Z-slider 12 has a holding plate 30 extending horizontally.
, The slide guide 31 is attached to the holding plate 30, and the X-slider 8 is slidably fitted. A stepping motor 32 is attached to the end of the holding plate 30 on the dolly side, and a pulley 33 is fitted to the rotary shaft of the motor to engage one end of the wire 34. The wire 34 is wound around the guide roller 35 and extends horizontally, and the other end is fixed to the X-slider 8. X-
A spring 36 is provided between the slider 8 and the holding plate 30 to urge the X-slider 8 in the groove direction. Also, X
An arm 37 is hung vertically on the slider 8 and a sensor unit 38 is provided at the lower end of the arm 37. The sensor unit 38 will be described. As shown in FIG. 2, guide shafts 40, 40 are attached to a pair of edge plates 39, 39 fixed to an arm 37, and a slider is slidably attached to the guide shafts 40, 40.
41 is provided, and the slider 41 has the edge plates 39, 39
The adjustment screw 42 rotatably mounted on the
The rotation of 42 allows the slider 41 to move up and down. A stylus 43 is hung on the slider 41, the stylus 43 is connected to a power source (not shown), and comes into contact with the material 1 to be welded so that there is electrical conduction.

The operation will be described below.

First, loosen the lock bolt 22 and insert the pinion 19 via the knob 21.
Is rotated to position the stylus 43 at substantially the center of the groove 15, and the lock block 22 locks the slide block 17. Next, the adjusting screw 42 is rotated to match the lower end of the stylus 43 with the position where the bead is to be formed.

Welding is started, truck 2 is run, and stepping motor
25 and 32 are driven alternately. The stylus 43 is lowered by the driving of the stepping motor 25, and the lower end comes into contact with the bottom surface of the groove or the front surface of the bead to detect the energization. When energized, the stepping motor 25 is reversed and the required amount is raised.
This pulling amount is performed according to a preset pulse number. When the stylus 43 is positioned in the height direction, the X-slider 8 is moved by the stepping motor 32, and the stylus 43 moves in the groove width direction. When the lower end of the stylus 43 comes into contact with the groove side surface, the stepping motor 32 is reversed and the stylus 43 is moved until it comes into contact with the opposite groove side surface. The movement amount at this time is detected by counting the number of pulses, and the groove width, that is, the welding line at that position can be detected. By repeating the above operation, the position of the welding line to be welded can be detected.

In such a mechanism, the rotation angles of the stepping motors 25 and 32 are transmitted to the wires 27 and 34 as the amount of circumferential movement by the pulleys 26 and 33, and the Z-slider 12 and X- are further transmitted through the wires 27 and 34.
It is transmitted to the slider 8. Further, the springs 29 and 36 always apply a required tension to the wires 27 and 34, and the rotation angles of the stepping motors 25 and 32 are set to the sliders 8 and 12.
Backlash does not occur in the process of being transmitted to.
Further, the rotation angle and the moving amount of the slider are exactly proportional to each other, and the detection accuracy thereof is extremely high.

Needless to say, a servo motor or the like may be used instead of the stepping motor and a steel belt or the like may be used instead of the wire.

As described above, according to the present invention, the drive mechanism has no backlash and the position of the welding line can be detected extremely accurately.

[Brief description of drawings]

FIG. 1 is a schematic perspective view of an embodiment of the present invention, FIG. 2 is a side view of a drive mechanism portion of the embodiment, FIG. 3 is a plan view of the same, and FIG. 4 is an explanatory view of a conventional example. 2 is a welding carriage, 8 is an X-slider, 12 is a Z-slider,
17 is a slide block, 25 and 32 are stepping motors,
26 and 33 are pulleys, 27 and 34 are wires, and 43 is a stylus.

Claims (1)

[Claims] A slide block is slidably mounted on a welding carriage in a groove width direction, and a Z-slider is slidably mounted on a column standing on the slide block and is mounted on a rotary shaft of one motor. Wire the one end of which is attached to the pulley to the Z-slider so that the wire will have the required tension.
-A slider is biased by a spring, an X-slider is slidably provided on the Z-slider in the groove width direction, and a wire attached to one end of a pulley attached to a rotary shaft of another motor is attached to the X-slider. -Fixed to the slider and biasing the slider with a spring to create tension in the wire,
A welding line copying apparatus characterized in that a stylus is provided at a lower end of an arm vertically provided on the X-slider.