JPH01130877A - Welding equipment - Google Patents

Abstract

PURPOSE:To perform accurate welding at low cost by a simple constitution by changing relative rotating speeds of two traveling wheels based on a measured result of the relative positional relation between welding torch and a groove to control the welding direction. CONSTITUTION:The control is carried out based on the measured result of the relative positional relation among the arc voltage or a welding current, the welding torch 30 and the groove detected by an arc sensor. The relative rotating speeds of the two traveling wheels 14a and 14b are change to adjust the welding direction. In addition, the traveling wheels 14a and 14b are rotated in the reverse directions respectively to turn a welding carriage 12. By this method, the accurate welding can be performed at a low cost of equipment by the simple constitution.

Description

[Detailed Description of the Invention] [Field of Application in Industry A] The present invention relates to welding line tracing control for a self-propelled welding device that performs work while traveling, and particularly relates to improvements in welding line rough tracing control means. It is something.

[Prior Art] Arc welding is the predominant welding method currently used, and when performing arc welding, it is customary to trace the groove using an arc sensor or the like.

The arc sensor detects the relative position between the welding torch and the groove based on the changing characteristics of the arc voltage or welding current, and is described in detail in Japanese Patent Application No. 61-94905. Then, the position of the welding torch is adjusted by a positioning device such as a slide block based on data from the sensor.

Therefore, in the past, in order to accurately control the tracing of weld lines, in addition to tracing the groove using an arc sensor, etc., as described above, welding carts were run on rails, or contact-type bars, etc. were used. Rough profiling was performed using a welding cart.

[Problems to be Solved by the Invention] However, when the welding equipment is run on rails, the work cannot be easily carried out because the rails must be laid. This has the disadvantage that it is greatly affected by the surface condition of the surface.

Therefore, there has been a strong demand for a rough tracing control method that does not require the above three rails or contact bars. However, in this case, a separate sensor for rough scanning would be required, which would pose a problem in terms of cost, so it has not been realized.

The present invention has been made in view of the above points, and an object of the present invention is to provide a welding device that accurately and easily obtains rough profiling regardless of the shape of the welding base material using an inexpensive rough profiling device.

[Means for Solving the Problems] A welding device according to the present invention includes a steering means for freely controlling the traveling direction of the welding device; and a positioning device whose deviation amount from a reference position reaches a predetermined amount. The above problem is solved by providing a control means for controlling the above-mentioned snake steering means according to the amount of deviation when the above-mentioned deviation occurs.

[Function] In this invention, the welding line is roughly traced by freely manipulating the running direction of the welding device by the control means and the manipulating means based on the amount of deviation from the reference position of the positioning device. , it is not affected by the shape of the welding base material, etc., and there is no need to lay rails or provide dedicated sensors. Therefore, the configuration is extremely simple, the cost of the device can be reduced, and more accurate welding line tracing control can be performed.

[Example] Hereinafter, an example of the present invention will be described in detail with reference to the accompanying drawings. In this embodiment, a fillet welding robot using an arc sensor will be described as an example.

FIG. 1 shows a schematic configuration of a square fillet welding robot, and FIG. 2 shows a bottom view of the robot.

In the figure, 10 is a square-shaped welding base material, 12 is a maneuverable welding cart, and two traveling wheels 14a, 14b and two ball casters 16 are each provided at the bottom end of this welding cart 12. .

Running wheels 14a, 14b, two drive motors 18a, 1
The welding cart 1 is rotated independently by the welding cart 8b.
2 can be moved and rotated.

To be more specific, when the welding cart 12 is run in a straight line, the two running wheels 14a and 14b are rotated in the same direction at the same speed, and when the welding cart 12 is steered, the two running wheels 1 are rotated.
The relative rotational speed of wheels 4a and 14b is controlled, and when the welding cart 12 is to be turned, the traveling wheels 14a and 14b are rotated in opposite directions at the same speed. In addition,
The pivot point for turning the welding cart 12 is the welding cart 1.
The electromagnetic magnet 20 is supported by the magnetic force of an electromagnetic magnet 20 disposed at the lower central part of the electromagnetic magnet 2, and the electromagnetic magnet 20 is driven up and down by excitation and release of a solenoid (not shown).

Further, the turning angle of the welding cart 12 is detected by an encoder 23.

On the other hand, the rough tracing of the welding line by the welding device is performed by the traveling wheels 14.
This is done by controlling the rotational speed of each of a and 14b. The details will be explained below.

During welding work, the arc voltage or welding current is measured by an arc sensor, the relative positional relationship between the welding torch 30 and the groove is detected, and the positioning axis (
(X-axis) Bevel tracing is performed by driving and controlling the slide 28. At this time, the traveling wheels 14a,
By controlling the rotational speed of each of the welding carts 14b, the running direction of the welding cart 12 is adjusted to perform rough tracing of the welding line.

On the other hand, a high-speed rotating arc welding torch 2 is mounted on the welding cart 12.
4 is installed, and the high speed rotating arc welding torch 24
is configured to be slidable in each direction by a Y-axis slide 26 and an X-axis slide 28. Above X
The shaft slide 28 is a mechanism that slides the high-speed rotating arc welding torch 24 in the horizontal direction by automatic tracing control of the welding line, and the Y-axis slide 26 slides the high-speed rotating arc welding torch 24 in the torch height direction so as to keep the arc length constant. 24
This is a mechanism that slides the

30 is a shield nozzle provided on the high-speed rotating arc welding torch 24.

Next, the operation and effect of the above embodiment will be explained with reference to FIGS. 3 and 4. FIG. 3 shows the circuit configuration of the rough scanning control, and FIG. 4 shows the running operation of the welding cart 12 thereby. Note that 1oo in the figure indicates a welding line. -Here, set the reference position of the xiP4II slide 28 to X. If the displacement from binding and xo is ΔX, and the displacement on the welding line 100 side is negative and the opposite side is positive,
The actual position of X@slide 28 is represented by X0+ΔX. For example, a position 200 mm from the tip of the torch 3o is the center of rotation of the welding cart 12, that is, a reference position Xo of the X-axis slide 28.

Under these conditions, welding is carried out by running the welding cart 12. At this time, the reference position X0 of the X-axis slide 28 is input in advance as an electrical signal to the operational amplifier 5o of the circuit shown in FIG. , and further the actual position X of the slide 28. +ΔX is manually applied to the same circuit each time.

In the figure, each signal of the manually input reference position Xo and the actual position (XO+ΔX) of the slider 28 is sent to the operational amplifier 5.
Subtract by o to obtain ΔX. Next, an operational amplifier 54 is used to make this data ΔX a value corresponding to the speed control signal 52.
and a variable resistor 56, one of which is output as is to an operational amplifier 58, and the other is output to an operational amplifier 62 after being converted into a positive/negative signal by an operational amplifier 60. These signals are added to the travel speed control signals 52 in operational amplifiers 58, 62, and then output as currents corresponding to the motors 18a and 18b to amplification converters 64, 66, respectively. .

Next, each motor 18a, 18b rotates the traveling wheel 14a at a rotational speed according to the traveling speed and the deviation amount ΔX of the positioning axis (X-axis) slide 28.

14b respectively.

To explain in detail, the running speed of the running wheels 14a, 14b and Δ
Depending on the absolute value of X, when ΔX<o, the running wheels 14b
The rotational speed of is made faster than the running wheel 14a, and conversely
At this time, the running direction of the welding cart 12 is corrected by making the rotational speed of the running wheels 14a faster than that of the running wheels 14b.

Although not shown in the figure, Xo and X. When comparing +ΔX, a dead zone is provided using a diode or a relay so that the diode is non-conductive for le+ signals below the bias voltage of the two diode tubes, and conductive for signals above the bias voltage. . That is, the circuit is configured such that it does not operate when the amount of deviation ΔX is less than a predetermined value.

As described above, in the above embodiment, the running direction of the welding cart 12 is freely steered by the motors 18a, 18b and the running wheels 14a, 14b based on xfq & the amount of deviation ΔX of the slide 28 from the reference position X0. Since the welding line is roughly traced by the welding line, the stroke of the X-axis slide 28 is shortened, and accurate welding line tracing control can be performed.
This has the advantage that no special sensor is required, the configuration is extremely simple, and the cost of the device can be reduced.

C. Effects of the Invention] As described above, according to the present invention, the cost of the apparatus can be reduced with a simple configuration, and accurate weld line tracing control can be performed.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram showing the external appearance of an embodiment of the present invention, Fig. 2 is a bottom view showing the main parts of the embodiment, Fig. 3 is a block diagram showing the operation of the embodiment, and Fig. 4 is a block diagram of the embodiment. It is an explanatory diagram showing operation. "Explanation of symbols of main parts" 12... Welding trolley, 14a, 14b... Traveling wheels,
18a, 18b...Motor, 28...X-axis slide, 30...Welding torch. Agent Patent Attorney Masatoshi Sato

Claims (3)

[Claims] (1) In a self-propelled welding device that performs welding while accurately tracing the groove of a welding torch by moving a positioning device, a steering means for freely controlling the traveling direction of the welding device; and the positioning device. A welding device comprising: control means for controlling the welding means in accordance with the amount of deviation when the amount of deviation of the device from a reference position reaches a predetermined amount. (2) The welding device according to claim 1, wherein the steering means is two running wheels that can each be independently controlled. (3) The welding apparatus according to claim 2, wherein the control means is a motor that varies the rotation speed of each of the two running wheels.