JP2604736Y2 - Arc stud welding machine - 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 stud welding machine capable of obtaining a high quality stud weld.

[0002]

2. Description of the Related Art Generally, in an arc stud welding operation, a defect may occur in a welded portion due to an unexpected situation. It was difficult to extract the weld defect. To cope with this, for example, the one described in JP-A-63-165077 has been proposed.

[0005] That is, in FIG. 5, S denotes a stud that is cast on a base material W, and the stud S is clamped by a holder 50 and is pressed against the base material W with its tip surrounded by an arc shield F. The holder 50 is fixed on a moving table 55 that moves along a shaft 54 that is moved over front and rear frames 52 and 53 of a base 51.
6 is attached to the lower part, and the cylinder rod
2 is attached. Accordingly, the operation of the air cylinder 56 causes the stud S to press against the base material W or move in the pulling direction. A potentiometer 131 is also attached to the moving table 55, and its meter axis is connected to the rear frame 53.
The resistance value of the potentiometer 131 changes in accordance with the movement of the moving table 55, and by detecting this as a voltage value, the amount of movement of the moving table 55 is detected.

As shown in FIG. 6, a stud S
Is moved backward by a certain set amount (2 to 3 mm) by exciting the magnet coil 2, and is turned forward by the spring 7 by turning off the magnet coil after the set time. It has a structure. The movement of the moving shaft 8 depends on the connecting plate 1.
4 is linked to a shaft 131A of a potentiometer 131 fixed to the gun body 1 through the shaft 4A. Accordingly, the movement of the moving shaft 8, that is, the movement of the stud along the axial direction is detected by the potentiometer 131.

[0005] The stud gun 20 is connected to the control device 60 and the potentiometer 131 is connected to the monitoring device 70. Of the values recorded by the monitoring device 70, the movement amount of the stud in the stud pushing process is determined by the operator. It is recommended that the value be compared with a separately prepared standard indentation appropriate value to determine whether the stud welding joint is good or bad, and when it is determined to be bad, the stud welding be performed again.

[0006]

By the way, in the arc welding operation, after one stud is welded, welding is performed one after another while changing the welding position, but usually 700 or more studs are welded per day. That is, due to the short stud welding time per rod and the wide range of movement of the workers, and in recent years, the size of work pieces to be welded such as bridges and buildings, there is a tendency to work at heights, Moreover, most of the cases where the scaffold is not good, most of the devices such as the monitoring device 70 and the control device 60 are set in a predetermined position, and the worker carries only the stud gun 20 to perform welding. Is the actual situation.

[0007] For each stud welding, the welding state is recorded by the monitoring device 70. In order to judge the welding joint for each stud welding, the worker moves away from the welding position and away from the welding position. Reciprocating with the monitoring device 70 is extremely inefficient and cannot be performed. Of course, if a monitor to determine the record of the monitoring device 70 is separately arranged, the above determination can be made for each stud welding. However, it is unacceptable to arrange the above monitor when labor costs rise.

For the above reasons, in the above device,
Substantially, after the stud welding operation, the operator compares the value recorded by the monitoring device with the appropriate standard indentation value to specify the defective portion of the stud welding joint. However, when the position to be welded is, for example, a base shape, the operator performs welding sequentially in the outward path and the return path while changing the position one after another, so that the welding is performed in a zigzag shape as a whole. Moreover, since hundreds of studs are welded per day, even if the 100th and 150th stud welded joints from the start of welding can be determined to be defective after welding, the welding route, that is, the order of welding, is grasped. Unless otherwise, the 100th and 150th welding positions could not be distinguished.

Generally, dials for setting welding conditions such as a welding current value and a welding voltage value are attached to a so-called remote box, and the remote box is connected to the control device 60 via a cable of 2 to 3 m. Are linked. Usually, when the work area of stud welding is wide, after appropriately setting the welding conditions by operating the dials, the remote box is arranged near the control device 60, and the operator carries only the stud gun 20. Is performing stud welding work. Even in this case, the operator determines the defective welding part based on the record of the monitoring device,
As described above, since the stud welding operation has been substantially completed, during the stud welding operation, accidental situations such as a third party accidentally touching the dials or other instruments touching the dials may occur. Even when the welding conditions are changed to a poor welding state, the determination of the poor welding portion is substantially made after the stud welding operation as described above. That is, in this case, all the welding locations after the change to the welding conditions that result in poor welding had to be redone.

[0010] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to, when a poor welding portion occurs during a stud welding operation, an operator grasp the occurrence state of the poor welding portion at a welding position. Can perform this processing work, and
An object of the present invention is to provide an arc stud welding machine with good workability that can reliably obtain a desired weld.

[0011]

The present invention is applied to an arc stud welding machine in which a control device is connected to a conventionally known arc stud welding gun. The feature is that a movement amount detection means of a movement axis for holding a stud and an alarm are provided in the gun body, a pushing amount setting device capable of presetting the pushing amount of the stud, and the movement amount detection means at the time of welding. And a control circuit that activates the alarm when the difference between the push-in amount detection value and the push-in amount set value is greater than or equal to an allowable value.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the illustrated embodiments. The arc stud welding gun used in the present invention corresponds to a conventionally known one.
The case where the one described in JP-A-17708 is used will be described.

That is, in FIG. 1, an electromagnet mechanism 6 comprising an electromagnetic coil 2, armor cores 3, 4 and a movable iron core 5 is disposed on a gun body 1, and is urged toward a workpiece W by a compression spring 7. The moving shaft 8 is attached to the movable iron core 5 and the moving shaft 8
The stud S is held via a holder 9. Also,
A stopper metal 11 whose position can be adjusted in the Z direction is provided to regulate the amount of displacement of the movable core 5 in the Z1 direction. further,
A contact member 12 whose set length in the Z direction is adjustable is supported by the gun body 1. Reference numeral 13 denotes a moving amount detecting means attached to the gun body 1 and has, for example, a potentiometer 131. The shaft 131A of the potentiometer 131 is connected to the moving shaft 8 via the connecting plate 14. Reference numeral 15 denotes an alarm. 31 is a pushing amount setting device for the stud S, and 32 is a control circuit. The control circuit 32 activates the alarm device 15 when the value detected by the detecting means 13 and the setting value of the setting device 31 do not have a desired relationship. The semi-automatic arc stud welding gun 20 is constituted by the above 1 to 12, and the arc stud welding gun 20, the moving amount detecting means 13,
An arc stud welding machine is constituted by the alarm 15, the push-in amount setting device 31, the control circuit 32, and a welding control device not shown.

Next, an arc stud operation using the semi-automatic arc stud welding gun 20 will be described.
First, the ends of the ferrule F and the stud S are brought into contact with the workpiece W in a state where the position of the contact member 12 is appropriately determined before welding. By operating the operation switch 16 in this state, the electromagnetic coil 2 is energized, thereby, the movable iron core 5 and the moving shaft 8 which is integral moves in Z ₁ direction. In this case, the end position of the stopper fitting 11 is set in advance so as to be a desired position. For example, the stud S is pulled up by δ _{1 in the} Z ₁ direction. After this,
After the set time the electromagnetic coil 2 is in the state OFF, the stud S is urged Z ₂ direction by the compression spring 7. Although the description is omitted, a welding current is supplied substantially simultaneously with the pulling of the stud S, and an arc is appropriately generated as in the conventional case. Stud S by the spring force of the compression spring 7 as described above is pushed, the arc stud welding of depression depth [delta] ₂ is performed.

By the way, in arc stud welding,
Pulling amount [delta] ₁ and push amount [delta] ₂ of the stud in the stud material of the stud, the diameter is selected to correspond to the welding conditions. That is, in FIG. 1, a value corresponding to the pushing amount δ ₂ is input to the pushing amount setting device 31 as a preset value. The amount of movement of the stud S in the arc stud welding operation is detected by the detecting means 13, and if the detected value and the set value do not have a desired relationship, the control circuit 32 causes the alarm 1
5, for example, an alarm lamp or an alarm buzzer is activated.

In arc stud welding, poor welding may be considered when the amount of indentation is insufficient or too large. However, usually, the thickness of the workpiece is sufficiently large with respect to the set value of the amount of indentation. In addition, the finished dimensions of the studs after welding do not often require such strict height accuracy.
Therefore, the control circuit 32 for determining poor welding issues an alarm when the indentation amount is insufficient by a certain amount or more and issues an alarm 1
5 is often sufficient. Here, as the alarm device 15, an alarm lamp, an alarm buzzer, or the like that draws attention to an operator, or a device that outputs a signal for transmitting a welding failure to another control circuit or a voltage signal is output. May be used alone or in combination. Of course, the present invention can be implemented by changing the control circuit 32 so that an alarm is issued as a welding failure even when the pushing amount is excessive.

By doing so, the alarm 15 is activated when a defective welding portion occurs, so that the operator immediately knows that the welding just performed is defective after welding one arc stud. Can be. For this reason, the re-work of stud welding can be performed immediately.

If the alarm 15 is actuated again when the stud welding is performed again, the welding condition set value and the set value of the pushing amount may not be the desired values due to an unexpected situation. By interrupting the work, investigating and setting again so as to be in a normal state, subsequent welding defects are avoided.

As described above, since the arc stud welding is sequentially performed while confirming that the alarm device 15 does not operate, the resulting welded portions are all high quality welded portions having no defective welds. Therefore, after the end of a series of arc stud welding operations, there is no need for the repair work conventionally required in connection with the determination of the defective welding part, so that the workability is good and the desired weld part can be reliably obtained. Arc stud welding work that can be performed.

Next, an example of a control circuit used in the present invention will be described. FIG. 2 is a connection diagram showing an embodiment of an alarm device control circuit 32 which generates an alarm when the pushing amount is smaller than a predetermined value, together with peripheral circuits. In the figure, reference numerals 1 to 16 and 31 denote the same functions as those in the apparatus shown in FIG. A is an AC power supply, and usually a commercial AC power supply is used. E is a welding power supply circuit that rectifies the power from the AC power supply A, converts it into power having characteristics suitable for arc stud welding, and outputs it. C is a welding power supply circuit E and a welding control circuit that controls the welding gun 1. Upon receiving the switch closing signal, the electromagnetic coil 2 is excited, the welding power source E is started, and the welding output is supplied to the stud S and the workpiece W for a predetermined time and then cut off. After the delay, a welding end signal is output.
The 13 is the moving amount detecting means of the moving shaft 8, and a potentiometer 131 which slider is locked in the retainer 9 moves in the Z ₁ -Z ₂ direction auxiliary DC power source 132.. 3
Reference numeral 2 denotes an alarm device control circuit for sending a signal to the alarm device 15 when the push-in amount is insufficient, and includes a storage circuit 321, a comparison operation circuit 322, a comparator 323, an allowable value setting device 324, an AND circuit 325, and a flip-flop. It comprises a circuit 326 and an alarm reset switch 327. Alarm control circuit 32
, When the operation switch 16 is closed at the start of welding, the storage circuit 321 stores the output V ₁ of the potentiometer 131 at that time according to the closing signal WS.

Since the electromagnetic coil 2 is excited by the signal WS at the start of welding and the tip of the stud S is pulled up from the state in which it comes into contact with the surface of the workpiece W, the welding power source E generates an output at the same time. An arc is generated between the workpiece and the workpiece W. After a predetermined time after the occurrence of the arc, the output of the welding power source E is cut off, and at the same time or slightly before or after this, the exciting current of the electromagnetic coil 2 is cut off. When the excitation current of the electromagnetic coil 2 is interrupted, the weld object side by the stud S is spring as described in FIG. 1 (Z ₂ direction)
And the tip of the stud S is pushed into the workpiece W. Waiting for the completion of the pushing operation, the welding end signal WF
Is output, the comparison operation circuit 322
Depression depth reads the stored contents V ₁ as an input the output signal V ₀ which output signals V ₂ and pusher amount setter 31 of the potentiometer 131 after pushing the stud S error _{ΔV = V 0 - (| V} 1 -V 2 |) Is calculated. The calculation result ΔV is compared with the set value α of the allowable value setting unit 324 by the comparator 323, and outputs a high level signal when ΔV> α. The output of the comparator 323 is supplied to a flip-flop circuit 326 through an AND circuit 325 which is opened by the welding end signal WF, and the flip-flop circuit 326 is set to operate the alarm 15. Here, the comparator 323, the AND circuit 325, and the flip-flop circuit 326 constitute a comparison / judgment circuit for judging whether or not the pushing amount error is within an allowable value. The alarm 15 continues to issue an alarm until the reset button 327 is pressed, and stops when the flip-flop circuit 326 is reset by the reset button 327. Although not shown in the figure, if the operation switch is not activated while the output of the flip-flop circuit is at the high level, the alarm is not overlooked and the next welding is not performed. Applicable to fully automatic welding machines.

In FIG. 2, the comparator 323 is
The absolute value of the pushing amount error ΔV is compared with the allowable value α, and | ΔV |
If the alarm 15 is operated by outputting a high level signal when> α, an alarm can be issued both when the pushing amount is insufficient and when the pushing amount is excessive. Further, in the embodiment shown in FIG. 2, so as to set as the depression depth setting device 31 of the set value, the value V _a = V ₀ -α obtained by subtracting the allowable value α depression depth instead of proper depression depth V ₀ It may be. The difference [Delta] V = V _a between the detection value V _1, V ₂ of the movement amount detecting means with a set value V _a is in this case -
When | V ₁ −V ₂ | is calculated, if the difference ΔV is negative or zero (ΔV ≦ 0), the shortage of the actual pushing amount with respect to the appropriate pushing amount is equal to or less than the allowable value, and ΔV is positive. (ΔV> 0)
Indicates that the shortage of the pushing amount exceeds the allowable value. Therefore, in the embodiment shown in FIG. 2, a high-level signal when ΔV = V _a − (| V ₁ −V ₂ |)> 0 is used instead of the comparison operation circuit 322, the allowable value setting unit 324 and the comparator 323. And a circuit that outputs a low-level signal when ΔV ≦ 0 is used, the circuit can be simplified.

FIG. 3 is a connection diagram showing an embodiment of the present invention when in this way, the minimum necessary amount of depression depth instead of proper depression depth setting device in the embodiment of FIG. 2 V _a (V _a = V ₀
-.Alpha., however, V ₀ is a proper depression depth, alpha is provided a setting device 31 'for setting the pushing amount error tolerance), also read from the output V _a, the memory circuit 321 of the pusher amount setter 31' welded The position signal V ₁ of the holder 9 at the start and the position signal V ₂ at the end of welding are input and the pushing amount error ΔV = V _a −
(| V ₁ −V ₂ |) is provided, and a comparison judgment circuit 322 ′ that outputs a high-level signal when ΔV> 0 and outputs a low-level signal when ΔV ≦ 0 is provided. The value setter 324 and the comparator 323 have been removed. The other elements in the figure have the same functions as those in the embodiment shown in FIG.

In the embodiment shown in FIG. 3, the position V ₁ of the holder 9 is stored in the storage circuit 321 at the start of welding, and the position signal V ₂ of the holder 9 at that time is determined by the welding end signal WF.
The previous set value V _a stored value V ₁ and the push amount setter 31
Are processed by the comparison and judgment circuit, and the pressing amount error ΔV = V _a
− | V ₁ −V ₂ | is calculated. When the error ΔV> 0, the insufficient amount of the necessary pushing amount is equal to or more than the allowable value, and it is a welding defect. A high-level signal is output, the flip-flop circuit 326 is set via the AND circuit 325, and the alarm 15 is set. Drives to report poor welding. ΔV ≦ 0
In the case of, since the shortage of the pushing amount is within the allowable value, it is determined that the welding is good, and the alarm 15 is not driven.

FIG. 4 is a connection diagram mainly showing a control circuit of an alarm device according to another embodiment of the present invention. In the figure, a movement amount detecting means 13 is provided on a rack 13 attached to a holder 9.
3 and a pinion 134 meshing with the rack 133 and a rotary encoder 135 that is driven to rotate by the pinion 134 and outputs a pulse of a different sign depending on the rotation direction for each unit rotation angle. The control circuit 32 includes an up / down counter 332, a comparison operation circuit 322, and a comparator 32.
3, tolerance setting unit 324, AND circuits 325 and 33
0, flip-flop circuit 326, reset switch 3
27, an inverter circuit 328, a signal delay circuit 329, and a monomultivibrator 331. Further, the display 17 has a display 17 for displaying for a certain period of time when welding is successfully performed by the output of the monomultivibrator 331. The other elements in the figure have the same reference numerals as those in the embodiment shown in FIGS.

In FIG. 4, when the operation switch 16 is pressed while the tip of the stud S is pressed against the workpiece W, the moving shaft 8 on which the holder 9 is attached is moved in the same manner as described with reference to FIG. Pulled up. At the same time, a welding power supply (not shown) supplies an output to the stud S and the workpiece W, so that an arc is generated. The up / down counter 332 is reset by the welding start signal WS output when the operation switch 16 is closed, and the counted content becomes zero.
Thereafter, when the holder 9 is pulled up, the rotary encoder 135 generates a negative pulse, and the up / down counter 332 counts this negative pulse. (Count down.) When the holder 9 stops at the position where the predetermined amount has risen and the set time has elapsed from the start of welding, the welding power supply stops supplying the output and the arc is cut off. At this time, the amount of movement of the holder is δ ₁ upward from the position where the tip of the stud S was in contact with the workpiece W, and the up / down counter counts down the number of pulses corresponding to this amount of movement. , the count value V _c has become a -δ _1.

When the stud S starts to descend at the same time as or before or after the output of the welding power source or before or after a command from a welding control circuit (not shown), the rotary encoder generates a positive pulse in reverse to the above, and Down counter 3
32 counts up this, the count value is slide into changes toward the positive direction from - [delta _1. When the stud S continues to descend and the holder 9 descends to the position at the start of welding, the count value becomes zero, but the holder 9 continues to descend and the force for lowering the moving shaft 8 and the force of the stud S When the tip and the melted portion of the workpiece W melt and pass through the melt-softened portion, they stop when the reaction force for deformation and burying of both is balanced. At this time, the position of the holder 9, that is, the difference between the welding start position and the welding end position, is managed as a stud pushing amount under welding conditions. At this time, the count content V _c of the up / down counter is equal to V _c = + Δ ₂ corresponds to this pushing amount.

Therefore, the welding end signal WF may be output after a lapse of a fixed time (set slightly longer than the time required for the stud descent to stop) from the time when the welding control circuit outputs the stud descent command. In response to the welding end signal WF, the up-down counter 332
Loaded into the counting contents V _c is the comparison operation circuit 322, the count value V _c is compared with a set value V ₀ which pusher amount setter 31 error signal ΔV = V ₀ -V _c is calculated. The error signal ΔV is input to the comparator 323 and compared with the set value α of the allowable value setter 324. The comparator 323 outputs a high-level signal when | ΔV |> α, and outputs a low-level signal when | ΔV | ≦ α. The high level signal of the comparator 323 sets the flip-flop circuit 326 via the AND circuit 325 opened by the welding end signal WF,
The alarm 15 is driven by the output of the flip-flop circuit. The output of the comparator 323 is also supplied to an inverter circuit 328, and the level is inverted.

As a result, when the error signal ΔV is | ΔV |> α (poor welding), the output of the inverter circuit 328 becomes low level and the AND circuit 330 remains closed.
On the other hand, when the error signal ΔV is | ΔV | ≦ α, the error of the pushing amount is equal to or less than the allowable value and the welding is good, so that the comparator 3
The output of 23 is at a low level, the AND circuit 325 is closed, and the AND circuit 330 is opened. As a result, a high-level signal is supplied to the mono-multi vibrator 331, and a high-level signal having a fixed time width is supplied to the display 17 to drive it to inform that the welding result is good.

When an alarm is issued with | ΔV |> α, the alarm is held by the flip-flop circuit 326, so that the operator confirms a welding defect, removes the cause of the defect, and then resets the reset switch 327. Continue to warn until pressed. Note that the signal delay circuit 329 provided at the other input terminal of the AND circuit 330 is used to output the comparison operation circuit 322 when the signal WF is supplied at the end of welding.
Calculates ΔV = V ₀ −V _c , and the result determines the output of the comparator 323 within the time required for the comparator to compare | ΔV | with the allowable value α, that is, from the input of the signal WF. During this period, the AND circuit 330 is opened to prevent the monomultivibrator 331 from outputting an erroneous signal.

In the embodiment shown in FIGS. 2 and 4, when an operation circuit having a characteristic having a small dead band before and after ΔV = 0 is used as the comparison operation circuit 322, the tolerance α is substituted by the dead band portion. May be. In this case, by using a circuit configured to output a high-level signal when ΔV = 0 (and in the dead zone) and to output a low-level signal at other times as the comparison operation circuit 322, The difference setting unit 324 may be omitted, and the output of the comparison operation circuit 322 may be directly supplied to the AND circuit 325 and the inverter circuit 328. Further, in FIG. 4, the inverter circuit 328,
It is not always necessary to provide a circuit for indicating good welding composed of the delay circuit 329, the AND circuit 330, the monomultivibrator 331, and the display 17.

Further, in each of the above-described embodiments, the alarm control circuit 32 is not only configured as hardware by elements and circuits having the respective functions as illustrated, but also a part or most of the software is implemented by a microcomputer. It may be realized by wear.

The stud welding start signal is provided by a dedicated operation switch provided on the gun body 1 or a foot-operated operation box, a changeover switch provided on the gun body 1 in addition to the operation switch 16, or an operation switch 16. The operation can be performed appropriately by using a combination of the operation and a timer, or providing a plurality of switches in a foot-operated or manual operation type operation box without providing operation switches in the gun body 1. .

Further, the moving axis detecting means can be implemented by attaching a direct-rotation / rotation conversion mechanism to the moving axis, and by providing a detector such as an encoder or a resolver.

Further, as the arc stud welding gun, various conventionally known ones are applied, and of course, the arc stud welding gun can also be applied as shown in FIG. The arc stud welding machine according to the present invention can be a fully automatic arc stud welding machine in which a robot holds an arc stud welding gun. In the case of full automatic,
In the case of poor welding, the alarm is activated and the arc stud welding is disabled unless a reset operation is performed. However, the same can be applied to the case of semi-automatic welding.

Incidentally, the alarm device may be a digital display device such as "poor welding" or "defective welding" so that the operator can confirm the display. In this case, since there is a possibility that the display of the worker may be overlooked, when the welding failure occurs, electrical control is performed so that the subsequent welding is disabled. It will be.

[0037]

As is apparent from the above description, in the arc stud welding machine according to the present invention, in particular, the moving amount detecting means of the moving shaft for holding the stud and the alarm are provided on the gun body, and the stud of the stud is provided. A push-in amount setting device in which the push-in amount can be preset, and a control circuit that activates the alarm device when a difference between the push-in amount detection value and the push-in amount set value by the movement amount detecting means during welding is equal to or more than an allowable value. With this arrangement, an alarm is activated when a defective weld occurs, which allows the operator to know that the weld completed immediately before near the welding position was defective, and immediately started reworking the stud welding. Can be implemented. Further, when the alarm is actuated again when the stud welding is performed again, the cause of the defect can be eliminated early by the investigation. Of course, according to the arc stud welding machine according to the present invention, since all of the resulting welds are high quality welds without defective welds, there is no work for repairing defective welds after the end of welding work. It is possible to perform an arc stud welding operation with good workability and capable of reliably obtaining a desired welded portion.

[Brief description of the drawings]

FIG. 1 is a front sectional development view showing an embodiment of the present invention.

FIG. 2 is a connection diagram mainly showing an example of an alarm control circuit used in the present invention together with peripheral circuits;

FIG. 3 is a connection diagram showing another example of the alarm control circuit used in the present invention.

FIG. 4 is a connection diagram showing another example of the alarm control circuit used in the present invention.

FIG. 5 is a diagram showing a first conventional example.

FIG. 6 is a diagram showing a second conventional example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 Gun body 8 Moving axis 13 Moving amount detecting means 15 Alarm 20 Arc stud welding gun 31 Stud pushing amount setting device 32 Alarm device control circuit 321 Storage circuit 322 Comparison operation circuit 323 Comparator 324 Permissible value setting device 327 Reset switch 332 Up / down counter

Claims (2)

(57) [Scope of request for utility model registration] An arc stud welding machine in which a control device is connected to an arc stud welding gun for changing a position of a moving shaft holding a stud to a contact position, a pulling position, and a pushing position between an object to be welded and the stud. In the gun body
Means for detecting the amount of movement of the moving shaft,
Depression depth setter for presetting a set value V ₀ which is the amount of pushing
When a storage circuit for storing the output V ₁ of the welding start of the movement amount detecting means, the output V ₁ of the output V ₂ and the storage circuit of the moving amount detecting means at the welding end of said pusher amount setter From the set value V ₀ , the pushing amount error ΔV = V ₀ − (| V ₁ −V ₂
|), And the allowable value α of the push-in amount error
And a preset allowable value setting unit for the comparison in comparison with the output [Delta] V of the operational circuit and a tolerance value alpha of the allowable value setter, | ΔV |> α defect determination determines that defective welding when the
A comparison and judgment circuit that outputs a signal, and that is attached to the gun body
An alarm that issues an alarm when the failure determination signal is input
Arc stud welding machine equipped with a vessel . 2. A moving shaft for holding a stud is provided on a workpiece to be welded.
At the contact position, pull-up position and push-in position between
Control device is connected to arc stud welding gun to change position
Arc stud welding machine
The rack attached to the holder of the moving shaft
Rotated and driven by pinion meshing with rack
Rotary that outputs pulses with different signs depending on the direction
Moving amount detecting means comprising an encoder, and pushing of the stud.
A push-in amount setting device for presetting a set value V ₀ of an indentation amount; an up-down counter which is reset at the start of welding and counts up or down the output pulse of the movement amount detecting means according to the sign during welding; At the time, a comparison operation circuit that calculates a push amount error ΔV = V ₀ −V _c from the output V _c of the up / down counter and the set value V ₀ of the push amount setting device, and an allowable amount α of the push amount error is set in advance. And an output Δ of the comparison operation circuit .
V is compared with the set value α of the allowable value setting device, and | ΔV |
> If α, determine welding failure and output failure determination signal
A comparison judgment circuit, which is attached to the gun body and judges the defect.
An alarm device for issuing an alarm when a signal is input .