JP3473284B2 - Arc welding equipment - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an arc welding device that improves arc start performance.

[0002]

2. Description of the Related Art Conventionally, one of the market demands for arc welding equipment is to improve arc start performance. In order to improve this arc start performance, conventionally, at the time of arc start, the timing of switching from the initial setting of the welding wire feeding speed to the steady setting of the welding wire feeding speed and the initial setting of the welding voltage Various measures have been taken for the switching timing of the steady voltage setting.

A conventional arc welding apparatus in which the timing of switching from the initial setting to the steady setting is devised will be described below with reference to FIG.

In the conventional arc welding apparatus, the welding output switch 1 for opening and closing the welding output and the welding output switch 1 which is turned on after a first predetermined time from the turning on of the welding output switch 1 Is turned off after a second fixed time from turning off the first timer circuit 2 and the welding output switch 1 is turned on at a third constant time from turning on, and the welding output switch is turned off. After that, the second that makes a signal that turns off in the fourth constant time
A timer circuit 3, a welding voltage control circuit 7 that receives a signal from the first timer circuit 2 to control the welding voltage between the current-carrying part of the wire 4 and the workpiece 6, and a signal from the second timer circuit 3 The motor control circuit 9 controls the welding wire feeding motor 8 and the feeding roller 10 which is driven by the welding wire feeding motor 8 and feeds the welding wire 4.

Further, both the first timer circuit 2 and the second timer circuit 3 generally use analog circuit type timers.

FIG. 4 shows a time chart of the welding output switch of the conventional arc welding apparatus, the signal of the first timer circuit 2 (welding voltage control) and the signal of the second timer circuit 3 (motor rotation speed control). .

In the conventional arc welding apparatus, the welding voltage is output after a first fixed time has passed since the operator turned on the welding output switch 1, and after a third fixed time, the rotation of the welding wire feed motor is started. Begins. After the worker turns off the welding output switch 1, the welding wire feed motor stops rotating after a second constant time, and the welding voltage output stops after a fourth constant time.
Abolish that. This timing is constant without straw engaged <br/> the set value of welding current regulator.

[0008]

In the conventional arc welding apparatus, the timing of starting the wire feeding and the generation of the welding voltage after the welding output switch is turned on is constant regardless of the set value of the welding regulator. Therefore, it is difficult to perform a smooth arc start from the low current region of the welding current to the high voltage region. Furthermore, since the timing of stopping the wire feeding and ending the application of the welding voltage varies after the welding output switch is cut off, the shape of the tip of the welding wire at the end of welding greatly varies, which may worsen the arc start. ing.

Further, when the arc start is repeated intermittently at a high frequency, after the operator turns on the welding output switch, there are variations in the timing at which the wire exits and the timing at which the welding voltage is generated. In addition, it has a drawback that the arc welding equipment cannot be operated.

The present invention realizes a smooth arc start from the low current region to the high current region of the welding current regardless of the setting value of the welding current regulator and makes the shape of the tip of the welding wire at the end of welding constant. It is an object of the present invention to provide an arc welding apparatus that enables welding to be performed as desired by an operator even if welding is repeated intermittently at high frequency.

[0011]

In order to achieve this object, according to the present invention, a clock pulse generating circuit for generating a clock pulse having a cycle corresponding to a set value of a welding current regulator is provided, and a welding output switch is provided. Clock signal is generated by the start signal of the second counter circuit, and two types of counter circuits, a first counter circuit and a second counter circuit, which count a constant pulse after the welding output switch is opened and closed and output an ON / OFF signal Is provided, the welding voltage control circuit for controlling the welding voltage is operated by the first counter circuit, and the motor control circuit for controlling the feeding motor of the welding wire is operated by the second counter circuit.

In the present invention, a clock pulse generating circuit having a cycle corresponding to the set value of the welding current regulator and a constant value pulse after the welding output switch is opened / closed are output as an on / off signal. 1 counter circuit and 2nd
Instead of installing two types of counter circuits, the clock pulse generating circuit that generates the reference clock is provided, and the number of pulses corresponding to the set value of the welding current regulator is counted after the welding output switch is turned on and off. A first counter circuit for outputting an on / off signal and a second counter circuit may be provided.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION In the arc welding apparatus of the present invention, the timing of starting wire feeding and generating welding voltage after the welding output switch is turned on is the smoothest with respect to the set value of the welding current regulator. It can be selected so that a good arc start is possible. Furthermore, the timing of stopping the wire feeding and ending the application of the welding voltage after the welding output switch is turned off can be selected so that the shape of the tip of the welding wire at the end of welding is minimized, and the clock pulse Since the delay time is digitally determined by using, there is almost no variation in the timing at which the welding wire is released and the timing at which the welding voltage is started after the welding output switch is turned on.

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. In FIG. 1, 11 is a welding output switch, 12 is a clock pulse generating circuit in which the cycle of the clock pulse is changed according to the set value of the welding current regulator 13, and 14 is the welding output switch 11 being turned on. The first counter circuit which counts N1 pulses to output an ON signal from the welding output switch 11 and turns off the welding output switch 11 and then counts N2 pulses to output an ON signal, 15 indicates that the welding output switch 11 turns on. Second counter circuit that counts N3 pulses and outputs an ON signal after the welding output switch 11 is turned off and counts N4 pulses and outputs an OFF signal after 5 is a welding voltage control circuit, and 6 is a welding voltage control circuit. Motor control circuit, 7 is a wire feeding motor, 20 is a welding wire 1
9 is a supply roller, 21 is an energizing portion for the welding wire 19,
22 is a base material for performing arc welding.

In the arc welding apparatus of the present invention, the clock pulse generating circuit 2 is provided so that the cycle of the clock pulse changes according to the set value of the welding current regulator 13, and the clock pulse is generated by the signal of the welding output switch 11. The first counter circuit 14 is configured to open and close the signal from the circuit 12, and the N1 pulse is detected and turned on after the welding output switch 11 is turned on, and the first counter circuit 14 is turned on after the welding output switch 1 is turned off.
Detects pulse and turns off. Further, the second counter circuit 15 is turned on with N3 pulse after the welding output switch 11 is turned on and is turned off with N4 pulse after the welding output switch 1 is turned off. Then, upon receiving a signal from the first counter circuit 3, the welding voltage control circuit 16 controls the welding voltage.
Further, receiving a signal from the second counter circuit 15,
The motor control circuit 17 controls the welding wire 19 by the wire feeding motor 18.

FIG. 2 is a time chart of signals of the welding output switch 11 and the first counter circuit 14 (welding voltage control) and signals of the second counter circuit 15 (motor rotation speed control) of the arc welding apparatus of the invention. Is.

In the arc welding apparatus according to the present embodiment, the clock signal output from the clock pulse generation circuit 12 changes its cycle in accordance with the set value of the welding current regulator 13. Therefore, the welding output switch It is possible to select the most appropriate value for the timing of starting the rotation of the wire feeding motor 18 and the generation of the welding voltage after 11 is input so that a smooth arc start can be performed.

In the arc welding apparatus of the embodiment, the wire feeding motor 1 is operated after the welding output switch 11 is turned off.
The rotation stop of No. 8 and the end timing of the application of the welding voltage also correspond to the set value of the welding current regulator 13 and the welding wire 19
Can be chosen to have the smallest tip shape.

Further, since the start / stop of rotation of the wire feed motor 18 and the opening / closing delay of the welding voltage control circuit 16 are digitally processed after the welding output switch 11 is opened / closed, time variations are caused. There is almost no.

When the set value of the welding current regulator 13 is low, the time delay is preferably short when the rotation of the wire feeding motor 18 is stopped and the welding voltage is ended after the welding output switch 11 is turned off. When the set value of the welding current regulator 13 is high, this time delay should be long.

Therefore, in the arc welding apparatus of this embodiment, when the set value of the welding current regulator 13 is low,
Welding current regulator 1 by shortening the cycle of the clock pulse signal
When the set value of 3 is high, by lengthening the cycle of the clock pulse signal, the operability of the welding output switch 11 is extremely improved in accordance with the operator's feeling.

The above description is based on the clock pulse generation circuit 12 having a cycle corresponding to the set value of the welding current regulator 13.
And a counter circuit that counts a certain number of pulses and outputs an on / off signal. Instead of the clock pulse generation circuit 12, a clock pulse generation circuit 12a that generates a reference clock is provided to adjust the welding current. Circuit 14a, 1 for counting the number of pulses corresponding to the set value (dotted line) of the instrument 13 and outputting an on / off signal
Even if 5a is used, the same effect can be expected.

That is, the first counter circuits 14, 14
a is N2 after the welding output switch 11 is turned on and detects the N1 pulse, and is turned off after the welding output switch 11 is turned off.
When the pulse is detected and turned off, the second counter circuits 15 and 1
5a is set to turn on with N3 pulses after the welding output switch 11 is turned on, and turn off with N4 pulses after the welding output switch 1 is turned off. The number of pulses of N1 pulse, N2 pulse, N3 pulse, N4 pulse is set. By setting the number of pulses corresponding to the set value of the welding current regulator 13, the rotation of the wire feeding motor 18 and the timing of generation of the welding voltage are smoothly arced after the welding output switch 11 is turned on. Wire feed motor 18
The timing of stopping the rotation and ending the application of the welding voltage can also be selected so as to reduce the shape of the tip of the welding wire 19 at the end of welding.

[0024]

According to the arc welding apparatus of the present invention, the timing of starting wire feeding and starting welding voltage application after the welding output switch is turned on is set to an optimum value corresponding to the set value of the welding current regulator. The shape of the tip of the welding wire at the end of welding is rearced because the timing of stopping the wire feeding and ending the application of welding voltage can be optimally controlled after the welding output switch is turned off. Since it has an ideal shape for starting, it will ensure an arc start,
Even when the arc start is repeated intermittently at high frequency, since the welding wire output timing and the welding voltage application start timing match exactly after the operator turns on the welding output switch, This has an excellent effect that an operator can operate the arc welding device with the welding output switch as he or she feels like a part of the body.

[Brief description of drawings]

FIG. 1 is a block of an arc welding device according to an embodiment of the present invention.

[Fig. 2] Time chart of welding output switch, welding voltage control, and motor speed control of the arc welding apparatus

FIG. 3 is a block diagram of a conventional arc welder.

FIG. 4 is a time chart of welding output switch, welding voltage control, and motor speed control of the conventional arc welding apparatus.

[Explanation of symbols]

11 Welding output switch 12, 12a Clock pulse generation circuit 13 Welding current regulator 14, 14a First counter circuit 15, 15a Second counter circuit 16 Welding voltage control circuit 17 Motor control circuit 18 wire feeding motor

Claims (3)

(57) [Claims] 1. A welding output switch for opening and closing the welding output,
A welding current adjuster that adjusts the welding current and a clock pulse generation circuit that changes the cycle of the clock pulse according to the setting value of the welding current adjuster are provided, and the clock pulse is generated by the start signal of the welding output switch. A pulse signal is generated from the generation circuit, N1 pulses are counted after the welding output switch is turned on and an ON signal is output, and N2 pulses are counted after the welding output switch is turned off. And a first counter circuit that outputs an off signal, and counts N3 pulses after the welding output switch is turned on and outputs an on signal, and outputs N4 pulses after the welding output switch is turned off. A second counter circuit that counts and outputs an off signal; the welding voltage control circuit that receives a signal from the first counter circuit to control the welding voltage; and the second counter circuit. Arc welding apparatus provided with the motor control circuit receives a signal from the counter circuit for controlling the welding wire feed motor. 2. When the set value of the welding current regulator is low,
The arc welding device according to claim 1, wherein the cycle of the clock pulse signal is shortened, and when the set value of the welding current regulator is high, the cycle of the clock pulse signal is lengthened. 3. A welding output switch for opening and closing the welding output,
A welding current adjuster that adjusts the welding current, a clock pulse generation circuit that generates a reference clock, and the number of pulses corresponding to the setting value of the welding current adjuster after the welding output switch is turned on are counted and the ON signal is output. A first cow that outputs and outputs an off signal by counting the number of pulses corresponding to the set value of the welding current regulator after the welding output switch is turned off.
Input circuit, and after the welding output switch is turned on, the number of pulses corresponding to the setting value of the welding current regulator is counted and an ON signal is output, and after the welding output switch is turned off, the welding current regulator A second counter circuit for counting the number of pulses corresponding to the set value of and outputting an off signal;
Before controlling the welding voltage by receiving a signal from the counter circuit of
From the welding voltage control circuit and the second counter circuit
It receives the signal and controls the welding wire feed motor.
Arc welding equipment equipped with a control circuit .