JPS58125368A - Control device for weaving welding machine - Google Patents

Abstract

PURPOSE:To eliminate the deviation in the welding start point in each time and the deviation in torch position with simple circuits by feeding the detection signal for weaving width back to a control circuit part for a motor which moves the welding torch back and forth during the stoppage of the torch. CONSTITUTION:In controlling weaving patterns, the position at the right or left end of a torch is detected with a position detector such as an OP amplifier 33 or the like and the signal thereof is used for detecting weaving width. More specifically, when the output of the amplifier 33 goes to the high level, a line 8 goes to the high level, and the output of a ring counter changes, whereby weaving control is accomplished. When the central stop position of the torch is detected with an OP amplifier 37, a line 9 goes to the high level and the signal thereof is fed to a speed controlling circuit part for a motor. This signal passes through a variable resistor 52 for setting speed and is inverted with an OP amplifier 54 to a command voltage for a servocontrol amplifier SA. When the torch does not operate, an analog switch 62 is conducted to turn the signal to the amplifier SA OV.

Description

[Detailed Description of the Invention] The present invention relates to a control device for a weaving welding machine that performs welding by reciprocating a welding torch from side to side.The weaving width can be set arbitrarily, and the welding torch is moved by its own weight. The purpose is to prevent the welding start point from shifting or shifting.

Generally, when welding using automatic welding equipment, variations in the groove shape and precision of the workpiece are a problem, so weaving welding is used as one method to deal with these problems. This weaving welding has the advantage that it is extremely unaffected by changes in base metal temperature, tack welding is less affected by beads, and a large amount of deposited metal can be obtained in one weld.

In addition, in weaving pattern control for such weaving welding, weaving width and weaving period (
Weaving speed) can be changed.

Conventionally, to control this weaving pattern, the output of a weaving pattern signal generation circuit that generates a preset weaving width and weaving period is applied to an operational amplifier (hereinafter referred to as OP amplifier), etc., and the output of the OP amplifier is amplified. After that, the motor that reciprocates the welding torch left and right is controlled, and the output of a potentiometer for position detection connected to the motor shaft via a gear etc. is fed back to the OP amplifier to obtain an arbitrary weaving width. There is a way to get it.

Also, a weaving pattern signal generation circuit.

There was also a method in which the potentiometer was used only to detect the weaving width.

However, in such conventional methods, the method using a weaving pattern signal generation circuit requires a complicated and expensive circuit, and the method that simply uses a potentiometer only to detect the weaving width may cause the welding torch to shift due to its own weight. Problems have arisen in that the first welding start is shifted.

The present invention has been devised in view of such conventional problems, and will be described below with reference to the drawings of FIGS. 1 to 4 showing one embodiment of the present invention.

Fig. 1 shows an example of a weaving pattern of a welding torch, and Fig. 2 shows a weaving pattern of a control device for a weaving welding machine according to an embodiment of the present invention.
(2) 7 is the output signal of the ring counter 4 shown in FIG. 2, and T1 to T2 are set by the variable resistors 22 to 24 shown in FIG.

In addition, in Fig. 2, line 1 has a start signal (ST
) is given, flip-flop 2 is set,
As the output terminal 3 becomes low level, the AND element 6
output becomes high level.

At this time, when the Qo of the ring counter 4 becomes high level, the welding torch moves to the left, and the feedback signal from the potentiometer 26 in FIG. 3 sets the weaving width set by the variable resistor 26 in FIG. When it comes to the value,
The line 8 becomes high level, and a clock is applied to the ring counter 4 through the OR element 11 and the flip-flop 7, so that the output of the ring counter 4 becomes Q. From Q.

to move to.

When the output of the ring counter 4 shifts to Q, the left-hand operation stops, the analog switch 18 becomes conductive (9), the capacitor 17 is charged to the value set by the variable resistor 22, and the left-end stop time T is will be counted. When the timer IC 16 times up, the inverter 16 and A
ND element 130R elements 12, 11, flip-flop 7
When the output of the ring counter 4 shifts to the Q2 gap, the welding torch moves to the right, and when the feedback signal from the potentiometer 26 in FIG. Similarly, a clock is given to the ring counter 4, and the ring counter 4
The output of Q2 shifts to Q3.

When the output of the ring counter 4 shifts to 03, the analog switch 19 becomes conductive through the OR element 21,
The capacitor 17 is charged with the value set by the variable resistor 23, and the center stop time T2 is counted.Similarly, when the center stop time T2 times up, the output of the ring counter 4 shifts to 04, and the signal on the line 8 Then, the output of the ring counter 4 shifts from 04 to 06N. When the output of the ring counter 4 shifts to Q5, the analog switch 2o becomes conductive, the capacitor 17 is charged with the value set by the variable resistor 24, and time T3 is counted. And at the count up of T3,
The output of ring counter 4 shifts from 06 to 06,
The welding torch operates in the left direction, and the output of the ring counter 4 changes from 06 to 07 in response to the signal on line 9.

Then, the output Q7 of the ring counter 4 turns on the analog switch 19 again through the OR element 21, and the capacitor 1 is turned on at the value set by the variable resistor 23.
7 is charged and T2 is counted. With this count up of T2, the output of ring counter 4 changes from 07 to Q. 1 and repeat the weaving pattern of FIG. 1 until the line 1 start signal is no longer present.

In addition, the start signal is connected to the inverter 27 so that it draws a weaving pattern of one cycle even if it is turned off at a point other than Q0.
self-maintained by

In addition, in FIG. 2, 6 is an internal clock of several tens of KHz.

Next, to explain the circuit of FIG. 3, the oP amplifier 33
is for weaving width detection, and a voltage obtained from a variable resistor 26 is applied to the inverting terminal. on the other hand,
The voltage obtained from the variable resistor 26 is applied to the non-inverting terminal, but when the analog switch 3o becomes conductive, the voltage obtained from the variable resistor 26 is inverted by the OP amplifier 28. When the analog switch 32 becomes conductive, the same, non-inverted voltage is applied. 29 and 31 are buffers for voltage level conversion; the output 04 of the ring counter 4 is input to the buffer 29, and the output of the ring counter 4 is input to the buffer 31.
Q of the output of. signal is input.

That is, in the case of left end detection, the inverter 34 and the AND element make the output of the OP amplifier 33 high level when the analog switch 32 becomes conductive and the voltage becomes higher than the terminal voltage of the variable resistor 25.

35, line 8 goes high. In addition, in the case of right edge detection, the analog switch 3o becomes conductive, and the output of the OP amplifier 33 similarly becomes high level.
Line 8 becomes high level.

Here, the variable resistor 26 has VDDC+8v) and VSS
(-sV) is applied, for example, VDD, O
The period between v is used to detect from the left end to the center stop position, and the period from 07 to 788 is used to detect from the center stop position to the right end.

37 is a ○P amplifier for detecting the center stop position, and when moving from the left end to the right and passing through the center stop position, the inverter 38
．． Line 9 is set to high level through OR element 39, ao, AND element 41, and OR element 42. Conversely, in the case of the left row from the right end, the inverter 38 and the NAND element 4
3.44, inverter 45, A N D element a e,
Line 9 is set to high level through OR element as and OR element 42.

The OP amplifier 47 is for signal inversion, and when the welding torch is at the center stop position, the OR element 48 inverter 49. Through the resistor 50, the issuing diode 61 is lit. This light emitting diode 61 can be used not only to indicate the center stop position but also to signal the original position.

Next, referring to FIG. 4, 62 is a variable resistor for speed setting, and the voltage obtained from which variable resistor 52 is the voltage that is inverted by the OP amplifier 54 when the analog switch 53 becomes conductive. becomes the command voltage of the servo amplifier (SA), and when the analog switch 65 becomes conductive, a voltage that does not invert is directly applied. When the analog switch 56 becomes conductive, the output voltage of the OP amplifier 37 shown in FIG. 3 is applied when the start signal is not applied. Note that 57, 58, and 59 are buffers for voltage level conversion, and the OR elements 60 are all passed through the buffer 57, and 02, . Q4 is the Q of the ring counter 4 through the OR element 61 to the buffer 58. , Q6, and the start signal of line 1 is input to the buffer 69, respectively. That is, for the right row,
The analog switch 63 is conductive, the analog switch 65 is conductive in the case of the left row, and the analog switch 66 is conductive when the start signal is not applied.

Further, if the welding torch does not operate after the start signal is given, the analog switch 62 becomes conductive and the signal to the servo amplifier is set to Ov. This analog switch 6
2, the signal obtained on line 10 in FIG. 2 is inputted through buffer 63.

That is, in the present invention, when the welding torch is reciprocating, the signal from a position detector such as the potentiometer 26 used to detect the weaving width for turn control is used to detect the weaving width, When the welding torch is stopped without reciprocating, it is configured to be used as a servo lock by connecting a foot to the speed control circuit of the motor that makes the welding torch reciprocate, and the weaving width can be varied. It can be set arbitrarily using the resistor 25, and when the welding torch is stopped without reciprocating, the servo lock is applied.
If the welding starting point is the same each time, and the welding torch is out of alignment when the control device is powered on, it will automatically return to the central stop position, and if the control device is powered on, welding will start. Even if the torch is in a horizontal or vertical position, the servo lock prevents it from shifting due to the welding torch's own weight.

However, the conventional method of using a potentiometer only to detect the weaving width requires a separate potentiometer to maintain the center stop position when the welding torch is stopped without reciprocating. In the present invention, this can be realized with one potentiometer 26. Moreover, since it can be realized without using a weaving pattern signal generation circuit, the circuit can be constructed easily and at low cost. Furthermore, in the present invention, the servo lock can be applied to the positions of the welding torch at the left end, right end, and center stop time when the welding torch is reciprocating by simply changing a part of the circuit.

As described above, according to the weaving welding machine control device of the present invention, the weaving width can be set arbitrarily, the welding start point does not shift each time, and the welding torch posture does not shift. The effect is that the circuit can be obtained at low cost.

[Brief explanation of drawings]

FIG. 1 is a pattern diagram showing an example of a weaving pattern of a welding torch, FIG. 2 is a circuit diagram showing a weaving pattern control circuit of a control device for a weaving welding machine according to an embodiment of the present invention, and FIG. FIG. 4 is a circuit diagram showing the weaving width setting circuit of the same weaving width setting circuit. FIG. 26...Potentiometer.

Claims (1)

[Claims] A position detector is provided to detect the weaving width for weaving pattern control, and when the welding torch is reciprocating, the signal from the position detector is used to detect the weaving width. A control device for a weaving welding machine, characterized in that when the welding torch is stopped without reciprocating, the welding torch is fed back to a speed control circuit section of a motor that reciprocates, and is used for servo locking.