JPH1034332A - Arc welding equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely execute arc starting by optimizing the timing of starting and stopping of feeding a wire, and the timing of starting and stopping of impressing a welding voltage after a welding output switch is made on or off. SOLUTION: A welding output switch 11 making on-off of the welding output and clock pulse generating circuits 12, 12a corresponding to the set value of a welding current regulator 13 are installed, and a pulse signal is generated from the clock pulse generating circuits 12, 12a by a starting signal from the welding output switch 11. Then, a 1st counter circuit 14, 14a which count a prescribed pulse after the welding output switch 11 is made on the output an on-signal, and count a prescribed pulse after the welding output switch 11 is made off and output off-signal; and a 2nd counter circuits 15, 15a which count a prescribed pulse after the welding output switch 11 is made on and output an on-signal and count a prescribed pulse after the welding output switch 11 is made off and output off-signal, are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an arc welding apparatus for improving arc starting performance.

[0002]

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

[0003] A conventional arc welding apparatus in which the timing of switching from the initial setting to the steady setting is devised will be described with reference to FIG.

A conventional arc welding apparatus includes a welding output switch 1 for opening and closing a welding output, and a welding output switch 1 which is turned on a first fixed time after the welding output switch 1 is turned on. The first timer circuit 2 and the welding output switch 1 for generating a signal to be turned off after a second fixed time after turning off are turned on for a third fixed time after the welding output switch 1 is turned on, and the welding output switch is turned off. And then make a signal that turns off in the fourth fixed time.
A timer circuit 3, a welding voltage control circuit 7 for receiving a signal from the first timer circuit 2 to control a welding voltage between the energized portion of the wire 4 and the work 6, and a signal from the second timer circuit 3 A motor control circuit 9 for controlling the welding wire feed motor 8 and a supply roller 10 driven by the welding wire feed motor 8 to feed the welding wire 4.

In general, both the first timer circuit 2 and the second timer circuit 3 use analog circuit type timers.

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

In the conventional arc welding apparatus, a welding voltage is generated after a first fixed time after an operator turns on the welding output switch 1, and a rotation of a motor for feeding a welding wire is performed after a third fixed time. Begins. The rotation of the motor for feeding the welding wire is stopped for a second fixed time after the worker shuts off the welding output switch 1, and the welding voltage is extinguished for a fourth fixed time. This timing is constant regardless of the set value of the welding current regulator.

[0008]

In the conventional arc welding apparatus, the timing of starting wire feeding and generating the welding voltage after the welding output switch is turned on is constant regardless of the set value of the welding regulator. For this reason, it is difficult to perform a smooth arc start from a welding current interruption region to a high voltage flow region. Furthermore, since the timing of stopping the wire feed and terminating the application of the welding voltage after the welding output switch is turned off varies, the shape of the tip of the welding wire at the end of welding varies greatly, thereby deteriorating the arc start. ing.

When the arc start is repeatedly and intermittently repeated at a high frequency, the operator turns on the welding output switch, and then the timing of the wire exit and the timing of the generation of the welding voltage vary. In addition, there is a disadvantage that the arc welding device cannot be operated.

The present invention realizes a smooth arc start from a low current range to a high current range of a welding current irrespective of the set value of a welding current regulator, and keeps the shape of the tip of a welding wire at the end of welding constant. It is an object of the present invention to provide an arc welding apparatus that can perform welding as desired by an operator even if welding is repeated intermittently at high frequency.

[0011]

In order to achieve this object, the present invention provides a clock pulse generating circuit for generating a clock pulse having a cycle corresponding to a set value of a welding current regulator, and comprises a welding output switch. A first counter circuit and a second counter circuit for generating a clock pulse signal in response to the start signal of the first and second counter circuits and outputting an on / off signal by counting a constant pulse after the welding output switch is opened and closed. The first counter circuit operates a welding voltage control circuit that controls the welding voltage, and the second counter circuit operates a motor control circuit that controls a motor that feeds a welding wire.

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

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the arc welding apparatus of the present invention, the timing of the start of wire feeding and the generation of 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 simple arc start is possible. Further, the timing of stopping the wire feeding and terminating the application of the welding voltage after the welding output switch is turned off can also be selected so that the shape of the tip of the welding wire at the end of welding is minimized, and the clock pulse Is used to digitally determine the delay time, so that there is little variation in the timing of the welding wire and the timing of starting the application of the welding voltage after the welding output switch is turned on.

An embodiment of the present invention will be described below with reference to FIGS. In FIG. 1, reference numeral 11 denotes a welding output switch, 12 denotes a clock pulse generating circuit in which the cycle of the clock pulse is changed in accordance with the set value of the welding current regulator 13, and 14 denotes when the welding output switch 11 is turned on. A first counter circuit which counts N1 pulses from the output and outputs an ON signal and counts N2 pulses and outputs an ON signal after the welding output switch 11 is turned off. Reference numeral 15 denotes a welding output switch 11 which is turned ON. A second counter circuit that counts N3 pulses and outputs an ON signal, and counts N4 pulses and outputs an OFF signal after the welding output switch 11 is turned off; 5, 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 section to the welding wire 19,
Reference numeral 22 denotes a base material for performing arc welding.

In the arc welding apparatus according to 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 a signal from the circuit 12, detects the N1 pulse after the welding output switch 11 is turned on, turns on the N1 pulse, and switches N2 after the welding output switch 1 is turned off.
Turns off upon detection of a pulse. The second counter circuit 15 is turned on by N3 pulses after the welding output switch 11 is turned on, and is turned off by N4 pulses 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, upon receiving a signal from the second counter circuit 15,
A welding wire 19 is controlled by a wire feed motor 18 by a motor control circuit 17.

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

In the arc welding apparatus according to the present embodiment, the clock signal output from the clock pulse generating circuit 12 changes its cycle in accordance with the set value of the welding current regulator 13, so that the welding output switch is used. The timing of the start of the rotation of the wire feed motor 18 and the generation of the welding voltage after 11 is input can be selected to be the most appropriate value so as to enable a smooth arc start.

Further, in the arc welding apparatus according to the embodiment, the wire feed motor 1 is turned off after the welding output switch 11 is turned off.
8 and the end timing of the application of the welding voltage also corresponds to the set value of the welding current regulator 13 and the welding wire 19.
Can be selected so as to minimize the shape of the tip.

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

When the set value of the welding current regulator 13 is low, the shorter the time delay between the time when the welding output switch 11 is turned off and the rotation of the wire feed motor 18 and the end of the welding voltage, the better. When the set value of the welding current regulator 13 is high, the longer the time delay, the better.

Therefore, in the arc welding apparatus according to the present embodiment, when the set value of the welding current regulator 13 is low,
The cycle of the clock pulse signal is shortened, and the welding current adjuster 1
When the setting value of 3 is high, the operability of the welding output switch 11 is extremely improved by making the cycle of the clock pulse signal longer to match the operator's feeling.

In the above description, the clock pulse generating circuit 12 having a cycle corresponding to the set value of the welding current regulator 13 has been described.
And a counter circuit that counts a constant pulse and outputs an on / off signal. In place 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. Counter circuit 14a, 1 that counts the number of pulses corresponding to the set value (dotted line) of the unit 13 and outputs an on / off signal
Similar effects can be expected by using 5a.

That is, the first counter circuits 14, 14
a is N2 after the welding output switch 11 is turned off and the N1 pulse is detected after the welding output switch 11 is turned on.
When the pulse is detected and turned off, the second counter circuit 15, 1
5a is such that the welding output switch 11 is turned on and then turned on with N3 pulses, the welding output switch 1 is turned off and turned off with N4 pulses, and the number of pulses of N1 pulse, N2 pulse, N3 pulse and N4 pulse is By setting the number of pulses corresponding to the set value of the welding current regulator 13, the rotation start of the wire feed motor 18 and the timing of the generation of the welding voltage after the welding output switch 11 is turned on realize a smooth arc start. Select an appropriate value and set the wire feed motor 18
The timing of stopping the rotation of the welding wire 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 the wire feeding and the application of the welding voltage after the welding output switch is turned on can be adjusted to an optimum value corresponding to the set value of the welding current regulator. Value can be selected and the timing of stopping the wire feed and the end of the application of the welding voltage after the welding output switch is turned off can be optimally controlled. Because it is an ideal form for starting, it is certain that the arc start will be secure,
Even when the arc start is repeated intermittently at high frequency, the timing of the welding wire and the start of the application of the welding voltage are exactly the same after the operator turns on the welding output switch. This is an excellent effect that allows the operator to operate the arc welding device with a welding output switch as if it were a part of the body.

[Brief description of the drawings]

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

FIG. 2 is a time chart of a 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 welding machine.

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

[Explanation of symbols]

 Reference Signs List 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 feed motor

Claims (3)

[Claims] A welding output switch for opening and closing a welding output;
A welding current adjuster for adjusting a welding current, and a clock pulse generating circuit for changing a cycle of the clock pulse in accordance with a set value of the welding current adjuster are provided, and the clock pulse is supplied by a start signal of the welding output switch. A pulse signal is generated from the generation circuit, a pulse is counted N1 times after the welding output switch is turned on, an ON signal is output, and a pulse is counted N2 times after the welding output switch is turned off. A first counter circuit that outputs an off signal, and counts N3 pulses after the welding output switch is turned on, 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; a welding voltage control circuit that receives a signal from the first counter circuit to control a welding voltage; Arc welding apparatus comprising a motor 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,
2. The arc welding apparatus according to claim 1, wherein the cycle of the clock pulse signal is shortened, and the cycle of the clock pulse signal is lengthened when the set value of the welding current regulator is high. 3. A clock pulse generating circuit for generating a reference clock, wherein a first counter circuit counts the number of pulses corresponding to a set value of a welding current regulator after the welding output switch is turned on. A circuit that outputs an on signal, counts the number of pulses corresponding to the set value of the welding current regulator after the welding output switch is turned off, and outputs an off signal, and the second counter circuit includes: After the welding output switch is turned on, the number of pulses corresponding to the set value of the welding current regulator is counted and an on signal is output, and after the welding output switch is turned off, the set value of the welding current regulator is corresponded. 2. The arc welding apparatus according to claim 1, wherein the circuit counts the number of pulses and outputs an off signal.