JP3134470B2 - 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 for performing stud welding while positioning a gun body with respect to an object to be welded. More specifically, the stud holder is attached to the stud gun body so that it can be displaced,
After the stud is brought into contact with the workpiece, the stud is pulled up by a predetermined amount to generate an arc between the stud and the workpiece, and the arc melts both members. TECHNICAL FIELD The present invention relates to an improvement in a fully automatic and semi-automatic arc stud welding machine for welding by pushing into a side.

[0002]

2. Description of the Related Art For example, a semi-automatic stud welding gun using an arc is disclosed in Japanese Patent Publication No. 60-5989.

[0003] That is, in FIG.
The shaft 51 is provided movably in the Z direction on the cylindrical portion 520 provided on the shaft _{2, and} a holder 9 for the stud ST is attached to one end of the shaft 51 in the Z ₂ direction via an electrical insulator. . 5
Reference numeral 3 denotes a compression spring disposed between a flange portion 510 fixed to the shaft 51 and a central protruding portion 521 provided at a substantially central portion in the cylindrical portion of the gun body 52. Reference numeral 54 surrounds the periphery of the shaft 51. Armor core 55 provided inside the armor core 54, a cover iron core 56 for closing the armor core 54,
Reference numeral 57 denotes a movable iron core that penetrates the holes of the armor core 54 and the electromagnetic coil 55, and a through hole for allowing the shaft 51 to freely pass therethrough is formed in a substantially axial core portion of the movable iron core 57. 5
8 is a movable iron core 57 having a constant width in the circumferential direction.
Arm 58 protruding from the axial end of the arm 58.
The of Z ₂ direction end claw 581 is provided. A disc-shaped lifting ring 59 is loosely fitted to the shaft 51, and the lifting ring 59 is pressed by a seat 522 provided on the central projection 521 by a compression spring 61 provided between the lifting ring 59 and the movable iron core 57. ing. The arm 581 is Z
_It is provided so as to be engaged with the lifting ring 59 when displaced in _one direction, and is pressed toward the central protruding portion 521 by a compression spring 62 provided between the armor core 54 and the arm 58. Reference numeral 63 denotes a stopper fitting screwed to the cover iron core 56 so that the position adjustment in the Z direction can be freely adjusted, and 64 is disposed so as to be movable in the Z direction by penetrating substantially through the axis of the stopper fitting 63. Further, the reading bar has a scale in the axial direction. Incidentally, 11 is a contact member which is disposed in the Z ₂ direction of the side surface of the gun body 52 so as to be substantially parallel to the axis 51, the abutting member 11 is positioned in the Z direction by a suitable fastener Adjustably fastened.

In the stud gun shown in FIG. 12, when the electromagnetic coil 55 is in a non-excited state, the movable core 57
And lifting rings 59 are compression springs 62 and 6, respectively.
Is directed in the Z ₂ direction by 1, A movable iron core 57 - with arm 58 is locked by the central projecting portion 581, riffs Thein toggling 59 is locked by the seat 522 of the central protrusion. In this case, a slight space is maintained between the claw 581 of the arm 58 and the lifting ring 59 in the Z direction. Furthermore, the electromagnetic coil 55 is when in the non-energized state, the flange portion 510 is pressed by Z ₂ direction by the compression spring 53, the lower plate 523 of the flange portion 510 and the gun body 52 is in contact therewith. In this state, the length of the holder 9 is, for example, L.
Attaching _a stud ST, in the Z ₂ direction than the tip of the tip abutment member 11 of the stud ST, for example [delta] ₂ by such a state projecting abutment member 11 by operating the fastener
Adjust the length of. However, when energizing the electromagnetic coil 55 in a state shown in FIG. 12, the movable iron core 57 is pulled in the Z ₁ direction until it abuts against the stopper fitting 63. At this time, the pawl 581 is moved in the Z ₁ direction together with the movable iron core 57, the pawl 581 is moved in the Z ₁ direction, the pawl 581
Abuts against a part of the circumference of the lifting ring 59 to tilt the lifting ring 59, so that the round hole of the lifting ring 59 through which the shaft 51 passes contacts the outer peripheral surface of the shaft 51, 51 and the lifting ring 59 are connected. Therefore, when the movable iron core 57 is pulled in the Z ₁ direction, immediately pawl 581, riffs Thein toggling 59 and shaft 51 is pulled in the Z ₁ direction together, the Z ₁ direction As the read bar -64 also axes 51 Moving. Accordingly, in the electromagnetic coil 55 is de-energized state, the stopper fitting 63 by screwing in the Z ₂ direction, the stopper fitting 63 is brought into contact with the movable core 57, thereafter, while confirming the scale reading bar -64 the stopper fitting 63 is screwed to the Z ₁ direction by a distance [delta] ₁ to position the stopper fitting 63.

After the above adjustment, in FIG. 12, the length L ₁ held by the holder 9 in a state where the electromagnetic coil 55 is not excited is shown.
The tip of the stud ST while contact with the object to be welded W, presses the gun body 52 in the Z ₂ direction. In a state where the respective tips of the stud ST and the contact member 11 contact the workpiece W (FIG. 13A), the flange 510 of the shaft 51 and the lower plate 5
23 are separated from each other by an interval δ ₂ . Is energized in this state to the electromagnetic coil 55, the movable iron core 57 is pulled in the Z ₁ direction, Z ₁ claw 581 with the position displacement of the movable iron core 57, riffs Thein toggling 59 and shaft 51 together form
In the direction by a distance δ ₁ . This state is shown in FIG.
(B). After the arc generated between the stud ST and the workpiece W is appropriately maintained in the state shown in FIG. 13 (b), when the energization to the electromagnetic coil 55 is cut off, the shaft 51 and the holder 9 are moved. It is biased in Z ₂ direction by the spring force of the compression spring 53. That is, as shown in FIG.
Studs ST and the retainer 9 13 distance from the state shown in _{(b) δ 3 (= δ 1 +} δ 2) is pulled by the Z ₂ direction. As a result, the stud ST protrudes by the distance δ _{2 in the} Z ₂ direction from the state where the respective tips of the stud ST and the contact member 11 abut on the workpiece W (FIG. 13A), and the stud ST is pushed in. welding of [delta] ₂ is performed.

[0006]

By the way, in the arc stud welding operation using a welding gun shown in FIG. 12, if the length L ₁ and the pushing amount δ ₂ of the target stud ST are selected, Since the position of the gun body 52 with respect to the workpiece W is uniquely determined, there are the following problems.

[0007] That is, as shown in FIG. 12, by urging the flange portion 510 of the shaft 51 by a compression spring 53 in the Z ₂ direction, in the state and the flange portion 510 and the lower plate 523 is in contact, for example, the length L ₁ stud ST is attached to the holder 9, and the tip of the abutting member 11 is Z ₁ from the tip of the stud ST.
The position of the contact member 11 is adjusted in the direction so as to be, for example, a position separated by the interval δ ₂ . Therefore,
If the values of the length L _{1 of the} stud and the pushing amount δ ₂ are selected, the position of the gun body 52 with respect to the workpiece W, for example,
Distance H ₂₀ between the holder of the object to be welded W and spacing H ₁₀ and welded object W and the gun body 52 between the lower end of gun body 52, primarily unless replaced with different lengths the components of the welding gun Is determined. For this reason, the holder 9 near the welding position
Does not prevent the movement of the region that may interfere with the end of the gun body 52, for example, when the object to be welded W ₁ is present, when the height of the object to be welded W ₁ is H ₁₀ or more, Cancer since the main body 52 and the weld object W ₁ abuts the stud length L
₁ welding is not possible. That is, when the object to be welded W ₁ is present in the area, the length of weldable stud there is a problem that is limited to more than a specific size. Furthermore, for example, a worker to weld while gripping the holder of the gun body 52, the arc stud welding of the so-called semi-automatic, when selecting the length L ₁ and the depression depth [delta] ₂ of the above as a stud, to be welded the interval H ₂₀ between the goods W and the holder has been determined, resulting in poor working efficiency.

On the other hand, A - in Kusutaddo welding, pulling amount [delta] ₁ and push amount [delta] ₂ of the stud in the stud material of the stud, the diameter, it is necessary to select appropriately according to the welding conditions. In particular, since the size of the stud and the length of the arc generated when the stud is pulled up have a delicate correlation, it is necessary to maintain the stud pulling amount to a desired value. For this reason, in the conventional arc stud welding gun shown in FIG. 12, the pulling amount δ ₁ and the pushing amount δ ₂ of the stud ST are visually adjusted while mechanically operating the components manually. I was Of course, if a mechanical positioning mechanism is provided on the arc stud welding gun, the structure becomes complicated and the cost rises. In addition, the manual mechanical adjustment work is troublesome, and the adjustment is poor due to an eye measurement error. Therefore, there is a problem that welding quality is deteriorated.
Of course, the welding operation, each time changing the dimensions and welding conditions of the stud in question, the pulling amount [delta] ₁ and depression depth [delta] ₂
The above problem has been magnified because adjustment work must be performed.

Further, in the arc stud welding work, since 700 or more studs are usually welded per day, a repetitive force frequently acts on each part of the stud welding gun. Therefore, when mechanical adjusting portion of the positioning condition uncertain cases and parts wear, pulling amount [delta] ₁ and depression depth [delta] ₂
However, there has been a problem that the welding quality gradually changes to cause a decrease in welding quality.

Further, in the above conventional arc stud welding gun, when tens of thousands of studs are welded, the fume generated during welding is slightly reduced.
Into the inside of the shaft, and gradually become oily and greasy on the surfaces of the shaft 51 and the lifting ring 59, and come into contact with the drilling hole of the lifting ring 59 which comes into contact when the shaft 51 is pulled up.
The part gradually wears. Therefore, when the stud ST is pulled up, an irregular sliding state occurs between the lifting ring 59 and the shaft 51, and the lifting ring 59 is appropriately replaced with a new one in order to eliminate the sliding state. Or
It was necessary to perform the work of removing the attached oil and fat.

In FIG. 12, the length is L ₁ − 1L
When the stud ST is used, as shown in FIG. 13 (a), the flange 510 of the shaft 51 and the lower part of the shaft 51 are in a state where the respective ends of the stud ST and the contact member 11 are in contact with the workpiece W. The plate 523 is more than the predetermined distance δ ₂ △
It becomes smaller by L. That is, the stud pulling amount δ ₁ is as desired, but the stud pushing amount is δ ₂ -ΔL, so that the pushing amount may be insufficient.

[0012] The present invention has been made in view of the above problems, and an object, even when selecting the length L ₁ and the depression depth [delta] ₂ of the stud to a desired value, the gun body with respect to the welded The position can be freely set, and at least the stud pulling amount can be set accurately and freely purely electrically without requiring a mechanical adjustment operation of the component parts. An object of the present invention is to provide an arc stud welding machine capable of changing a moving speed, particularly a speed during a pushing process, so as to obtain an optimum welding result by electrically moving a stud holder.

[0013]

According to a first aspect of the present invention, there is provided a gun body positioned with respect to an object to be welded, and a holder provided on the gun body for holding a stud. The present invention is applied to an arc stud welding machine having a holder driving mechanism for displacing at least a pulling state for generating an arc with respect to a contact position with the holding member and a pushing state after melting. It is characterized by an electric driving device that moves the holding tool in the longitudinal direction of the stud, and a moving amount that is electrically connected to the driving device and that allows at least a pulling amount of the stud to be preset. A setting device and a drive control circuit for displacing the holder in accordance with a set value of the movement amount setting device are provided.

According to a second aspect of the present invention, a gun body and a holder disposed on the gun body for holding a stud are pulled to generate an arc with respect to a contact position between the workpiece and the stud. A holder driving mechanism for at least displacing the upper state and the pushed state after melting, and a contact member that is in contact with the workpiece to perform positioning of the gun main body, and that an operator operates the gun main body. It is applied to an arc stud welding machine that performs welding while holding a holder. It is characterized by an electric driving device that moves the holding tool in the longitudinal direction of the stud, and a moving amount that is electrically connected to the driving device and that allows at least a pulling amount of the stud to be preset. A setting device and a drive control circuit for displacing the holder in accordance with a set value of the movement amount setting device are provided.

According to a third aspect of the present invention, a gun body positioned with respect to an object to be welded, and a holder disposed on the gun body and holding a stud are provided at a contact position between the object to be welded and the stud. On the other hand, the present invention is applied to an arc stud welding machine having a holder driving mechanism for displacing at least a lifting state for generating an arc and a pushing state after melting. It is characterized by an electric driving device that moves the holding tool in the longitudinal direction of the stud, a movement amount detector that detects a moving amount of the holding tool moved by the driving device, and at least the stud. When the holding amount reaches the set value of the moving amount setting device, the moving amount setting device which can preset the lifting amount of the moving amount and the setting value of the moving amount setting device and the detection value of the moving amount detector are input. And a servo control circuit for stopping the movement of the holder.

According to a fourth aspect of the present invention, a gun body and a holder provided on the gun body for holding a stud are pulled to generate an arc with respect to a contact position between the workpiece and the stud. A holder driving mechanism for at least displacing the upper state and the pushed state after melting, and a contact member that is in contact with the workpiece to perform positioning of the gun main body, and that an operator operates the gun main body. It is applied to an arc stud welding machine that performs welding while holding a holder. It is characterized by an electric driving device that moves the holding tool in the longitudinal direction of the stud, a movement amount detector that detects a moving amount of the holding tool moved by the driving device, and at least the stud. When the holding amount reaches the set value of the moving amount setting device, the moving amount setting device which can preset the lifting amount of the moving amount and the setting value of the moving amount setting device and the detection value of the moving amount detector are input. And a servo control circuit for stopping the movement of the holder.

According to a fifth aspect of the present invention, a gun body positioned with respect to an object to be welded, and a holder provided on the gun body and holding a stud are provided at a contact position between the object to be welded and the stud. On the other hand, the present invention is applied to an arc stud welding machine having a holder driving mechanism for displacing at least a lifting state for generating an arc and a pushing state after melting. It is characterized in that a speed setting device for setting the speed at the time of pushing the stud is added to the third invention, and a servo control circuit for performing both position control and speed control.
In this example, a control circuit is used.

According to a sixth aspect of the present invention, there is provided a gun body and a holder provided on the gun body for holding a stud, wherein a pull for generating an arc with respect to a contact position between the workpiece and the stud is provided. A holder driving mechanism for at least displacing the upper state and the pushed state after melting, and a contact member that is in contact with the workpiece to perform positioning of the gun main body, and that an operator operates the gun main body. It is applied to an arc stud welding machine that performs welding while holding a holder. It is characterized in that a speed setting device for setting the speed at the time of pushing the stud is added to the fourth invention, and a servo control circuit for performing both position control and speed control as a servo control circuit. It uses a control circuit.

According to a seventh aspect of the present invention, in the fifth and sixth aspects of the present invention, the setting signal of the speed setting device is set to two stages, and when the stud is pushed, the speed setting value of the first half of the pushing stroke in the latter half of the pushing stroke is reduced. Is set to a low setting value.

According to an eighth aspect of the present invention, in the fifth to seventh aspects, the set value of the speed setting device is a signal that changes continuously, and the latter half of the stud pushing stroke is gradually slower than the first half of the pushing stroke. It is characterized in that the set values are as follows.

According to a ninth aspect, in the fifth to eighth aspects, the speed setting signal is determined in relation to the moving amount.

According to a tenth aspect of the present invention, in the first to ninth aspects of the present invention, as the movement amount setting device, a setting device capable of presetting both a stud pull-up amount and a pushing amount is used. Things.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the illustrated embodiments. For example, a description will be given of semi-automatic arc stud welding. In FIGS. 1 to 3 of the first embodiment, reference numeral 1 denotes a gun main body having a holder 101 gripped by an operator. In addition, an operation switch 2 for welding operation is provided, and various cables are appropriately supported. Reference numeral 3 denotes a rotating member rotatably supported by the gun body 1 via a bearing 4.4. A female screw 301, most preferably a so-called ball nut, is integrally formed with the rotating member 3 at the axis of the rotating member 3. It is arranged in. 5
Is an electric driving device supported by the gun body 1, for example, a rotary electric motor. The output shaft of the electric motor 5 and the rotating member 3 are appropriately connected via a speed reducer and a rotation transmitting member such as a belt or a gear. ing. Reference numeral 6 denotes a detector for detecting a driving amount of the electric motor 5, for example, a rotary encoder.

Reference numeral 7 denotes a holding shaft provided with a male screw 701 screwed to the female screw 301 of the rotating member 3, optimally a ball screw. At least one shaft is provided outside the holding shaft 7. A direction groove 702 is provided. Reference numeral 8 denotes a locking member supported by the gun body 1, for example, a slide key.
02, the holding shaft 7 is supported on the gun body 1 so as to be movable only in the axial direction, that is, only in the Z direction. Reference numeral 9 denotes a holder for holding the stud ST, which is supported on the holding shaft 7 via an appropriate electrically insulating member. Reference numeral 11 denotes an abutting member for abutting on the workpiece W to position the gun body 1.
Is supported by the gun body 1 so that the position in the long axis direction, that is, the Z direction can be set freely. Reference numeral 20 denotes a control circuit of the driving device 5 for displacing the holder 9, and reference numeral 21a denotes a movement amount setting device that sets the movement amount of the holder 9 as an electric signal by a variable resistor, a push button switch, a rotary switch, or the like. And the control circuit 20 controls the movement amount setting device 21a.
And the output of the movement amount detector 6 are input, and the holder 9 is positioned at a position where both inputs coincide. A semi-automatic arc stud welding gun 30 is constituted by the above 1 to 11, and a servo control circuit for controlling the movement amount of the holder 9 by the movement amount setting device 21a, the movement amount detector 6, and the driving machine control circuit 20 is constituted. A stud welding machine is constituted by the welding gun 30, a servo control circuit, and a welding power supply not shown.

Next, a semi-automatic arc stud welding operation using the stud welding gun 30 will be described. FIG.
First, when the holder 101 of the gun body 1 is easily gripped, for example, the distance between the workpiece W and the holder 101 is H _21.
After adjusting the position of the contact member 11 so that
1 is integrally supported on the gun body 1. Thereafter, while gripping the operator the holder 101 of the gun body 1, for example, by operating the operation switch 2, an appropriate position of the holding shaft 7 Z ₁ direction, for example, the position of the moving end of the Z ₁ direction Moved to That is, the operation of the operation switch 2 causes the electric motor 5 to rotate in the reverse direction, thereby rotating the rotating member 3 via the rotation transmitting member. By the way, since the holding shaft 7 is supported by the locking member 8 so as to be movable only in the Z direction with respect to the gun body 1, when the rotating member 3 rotates in the reverse direction, the holding screw 7 is screwed into the female screw 301 of the rotating member 3. shaft 7 is moved in the Z ₁ direction.

In this state, the operator mounts a desired stud ST on the holder 9. Thereafter, while the tip end of the contact member 11 is brought into contact with the workpiece W to position the gun body 1, for example, the operation switch 2 is appropriately operated to rotate the electric motor 5 forward, thereby holding shaft 7 and studs ST is moved in _{Z 2} direction. In this case, for example, a voltage is applied between the stud ST and the workpiece W, and when the tip of the stud ST and the workpiece W are electrically short-circuited, the electric motor 5 is stopped.

By the way, if the stud ST is specified to have a desired material and dimensions, the stud lifting amount δ ₁ and the stud pushing amount δ ₂ are known as welding data. On the other hand, the rotation amount resolution of the detector 6, for example, P pulse / 1
Since the rotation is known and the reduction ratio from the electric motor 5 to the holding shaft 7 and the rotation lead angle are known, the amount of movement of the holder 9 with respect to the unit detection value of the detector 6 is determined by the stud welding gun 30
It is known as Therefore, the pulling amount δ ₁ and the pulling amount δ ₃ (= the pulling amount δ) based on the state in which the tip of the stud ST and the tip of the contact member 11 abut on the workpiece W.
Set the value corresponding to ₁ + the push amount δ ₂ ) as a preset value. Of course, as described above, the amount of movement of the holder 9 with respect to the unit detection value of the detector 6 is known, so the set values are the pull-up amount δ ₁ and the pull-down amount δ ₃ or the push-in amount according to a separately prepared conversion table. δ ₂ and the detected pulse equivalent value Δ1,
Or preset as Δ3 or Delta] 2, or by setting the pulling amount [delta] ₁ and cuts the amount [delta] ₃ or depression depth [delta] _2, the detection pulse equivalent value in the setter 21 .DELTA.1, be converted into Δ3 or Delta] 2 it can.

[0028] As described above, after the leading end of the stud ST is in contact with the object to be welded W, automatically, or by appropriately switching operation, the motor so that the studs ST and the retainer 9 is moved in the Z ₁ direction 5 is reversed. That is, the driving of the electric motor 5 is detected by the detector 6, the motor 5 is driven in the reverse direction until the detection signal becomes pulling amount [delta] _1. Motor 5 is stopped when the pulling amount of the stud ST becomes [delta] _1. The output of the welding power source, like the prior art, after the stud ST comes into contact with the object to be welded W, the positional displacement in the Z ₁ direction of the stud ST are started simultaneously,
Alternatively, an arc is generated between the stud ST and the workpiece W at the moment when the stud ST is supplied from the workpiece W just before the start, and is pulled up from the workpiece W.

[0029] After appropriate considering the molten state and just before pulling of the stud ST after the above is [delta] _1, or later studs ST and the weld object W, for example, stack
After the metal enters the molten portion of the workpiece, the supply of the welding current is cut off. Then, with the electric motor 5 is rotated forward so that the stud ST and the retainer 9 is moved in the Z ₂ direction, studs ST by a detector 6 the control circuit is moved in the Z ₂ direction setting amount [delta] ₃ The arc stud welding is completed. Needless to say, in this case, the pushing amount of the stud ST into the workpiece W is δ ₂ (= δ ₃ −δ ₁ ). After welding,
Automatically or by operating the operation switch 2, suitably moved in the Z ₁ direction retainer 9 welding one cycle is completed. Incidentally, the movement of the Z ₁ direction of the holder 9 may be a post-welding can be done before the next stud mounted or after.

Next, an example of a control circuit for automatically adjusting the pulling amount δ ₁ and the pushing amount δ ₂ will be described. FIG.
FIG. 4 is a connection diagram showing an example of a device in which the electric motor 5 is operated by presetting a pulling amount δ ₁ and a pushing amount δ ₂ so that these values are automatically set. In the figure, a control circuit 20 includes a movement amount setting device 21a, a comparator 22a, D / A converters 23a and 23b, an up / down counter 24, an arithmetic processing circuit 26, and a contact detector for detecting a contact between the stud ST and the workpiece W. 27 and an auxiliary power supply 28. E denotes a welding power source to which electric power is supplied from an AC power source A, and an output terminal is connected to the holder 9 and the workpiece W by a cable. In the other parts of the figure, those having the same functions as those in the example shown in FIG.

In the apparatus shown in FIG. 3, the moving amount setting device 21a
Presets a pull-up amount δ ₁ , pushing-in amount δ ₂ or pull-down amount δ ₃ (= δ ₁ + δ ₂ ) when pulling up from the state where the tip of the stud ST is in contact with the workpiece W, and calculates Each data is output in response to a request from the processing circuit 26. The contact detector 27 has a stud ST attached to the holder 9.
When the short-circuit current flows from the auxiliary power supply 28 when the tip of the motor comes into contact with the workpiece W, this is detected, the up / down counter 24 is reset, and the contact detection signal is sent to the arithmetic processing circuit 26 to Stop rotation of 5. The arithmetic processing circuit 26 sets the setting signals δ ₁ and δ from the setting unit 21a.
₂ or δ ₃ is temporarily stored , and in response to signals from the start command switch 2 and the contact detector 27, the motor 5
And a sequence control for sequentially outputting forward and reverse command signals to the controller, for example, a circuit using a microcomputer is used.

The operation of the apparatus of FIG. 3 will be described with reference to the flowchart of FIG. Prior to the work, the lifting amount δ ₁ and the pushing amount δ ₂ (or the lowering amount δ ₃ ) are set according to the diameter, material, required welding quality, etc. of the stud ST to be welded. The holder 9 is assumed to be moved to an appropriate position in the Z ₁ direction beforehand FIG. When a start command is given by the operation switch 2 in this state, the arithmetic processing unit 26 outputs a forward rotation signal to the electric motor 5 by this, and the electric motor 5 rotates forward by this signal to move the holder 9 downward in the figure.
That is moved in the Z ₂ direction. When the tip of the stud ST comes into contact with the workpiece W by the forward rotation of the electric motor 5, a short-circuit current flows from the auxiliary power supply 28 to this contact portion, and the contact detector 2
7 detects this and sends a contact detection signal s to the arithmetic processing circuit 26.
Outputs ₁ . The arithmetic processing circuit 26 thereby reads out the pull-up amount signal δ ₁ and outputs it to the comparator 22 a via the D / A converter 25.

On the other hand, the contact detection signal s ₁ is also supplied to the counter 24 to reset the counting content of the counter 24. As a result, the output of the counter 24 becomes zero, and the other input of the comparator 22a becomes zero. In this state, the servo amplifier reverses the electric motor 5 and moves the holder 9 upward (Z ₁
Direction). The stud S is raised by raising the holder 9.
When the short circuit between T and the workpiece W is eliminated, the contact detection signal s
_{When 1} disappears, the counter 24 is released from the reset state, and starts counting output pulses of the detector 6.

On the other hand, simultaneously with the generation of the contact detection signal s ₁ ,
Alternatively, the arithmetic processing circuit 2 is simultaneously
6 outputs an output start command signals s ₂ with respect to the welding power source E. As a result, the output of the welding power source E is supplied between the stud ST and the workpiece W, and a short-circuit current flows because the two are short-circuited. Arcs occur when leaving. Motor 5, increasing only holder 9 pulling amount [delta] ₁ that is set, both inputs of the comparator 22a is balanced, and stops at that position. During this time, the arc continues for the set time of the energization timer set by the arithmetic processing circuit 26. Signal s ₂ disappears the energization timer expires, the welding power source E is to cut off the output A - click disappears. At the same time, the arithmetic processing circuit 26 reads out the data of the depression amount δ ₂ and supplies an analog signal (sign is opposite to the previous signal δ ₁ ) corresponding to the signal δ ₂ to the comparator 22 a, thereby making a comparison. Vessel 22a
When the input signal becomes unbalanced, the motor 5 rotates forward to move the holder 9 downward. The amount of movement is detected by the detector 6, the up-down counter 24 by the output signal is down-counting in contrast to the previous count value is sequentially decreased from the previous [delta] _1, - [delta ₂ Strain through zero Is reached, the two input signals of the comparator 22a are balanced and stopped.
(End of push-in operation)

At this time, the stud ST first moves the workpiece W
The tip becomes pushed position by downward (Z ₂ direction) [delta] ₂ than when in contact, the depression depth [delta] ₂ is penetration of the stud ST to. Pushing is held by directly setting time of the holding timer after the electric motor 5 to complete the stop, then the electric motor 5 is holder 9 is reversed again driven in the Z ₁ direction, the next stop in the appropriate position Prepare for welding.
Note that after mounting studs ST, holder 9 while stopped at an appropriate position in the Z ₁ direction, it is possible to zero the count contents by resetting the counter 24. . in this case,
The detector 6 obtains a moving amount δ ₀ from the start position to the stud ST moving in the Z ₂ direction and coming into contact with the workpiece W. The moving amount data δ ₀ and the set data δ ₁ ,
pulling and pushing of the stud ST appropriately using the [delta] ₂ is performed.

Of course, when it is necessary to change the set values of the stud pull-up amount δ ₁ and the push-in amount δ ₂ , the input set value to the movement amount setting unit 21 a may be appropriately selected, that is, Since adjustments can be made purely electrically using resistors, pushbutton switches, rotary switches, etc., adjustments can be made quickly and extremely easily compared to the case where mechanical adjustments of components are performed as in the past. And the conventional positioning mechanism by mechanical abutment is not adopted, so that the structure of the arc stud welding gun can be simplified and manufactured at a low cost. And the welding quality is not degraded due to looseness of the positioning mechanism, etc.
For each stud welding, accurate welding according to the set value input to the movement amount setting device 21a is performed.

Further, since the position of the gun body 1 in the Z direction can be freely set by adjusting the position of the contact member 11 prior to welding, the arc stud welding can be efficiently performed by setting the posture suitable for the worker. be able to.

[0038] Furthermore, even if there is welded object W ₁ protruding Z ₁ direction in the vicinity of the welding position, the contact member 11 as the gun body 1 is positioned in the Z ₁ direction than welded object W ₁ By adjusting, the desired arc stud welding can be performed.

Further, since the stud lifting amount δ ₁ and the pushing amount δ ₂ are set based on the state where the contact member 11 and the stud ST are in contact with the workpiece W, the stud length varies. Stud pulling amount δ ₁
And the pushing amount δ ₂ are not affected at all. Therefore, the desired uniform quality welding is performed.

[0040] Note that after pulling the stud ST, when moving the stud ST in Z ₂ direction, i.e. the stud S
If the moving speed after the stud ST comes into contact with the molten portion on the side of the work to be welded during the pushing of T is high, the molten metal is scattered and a good welding result cannot be obtained. For this reason, at the time of pushing, the speed after the stud is pushed into the vicinity of the contact position between the stud and the work to be welded before pulling is substantially lower than the initial speed of pushing the stud. If this is the case, the tact time at the time of pushing can be shortened, and high-quality welding that does not scatter the molten metal can be performed.

FIG. 5 shows that the position and the speed are automatically set to the set values by presetting the pulling amount δ ₁ and the pushing amount δ ₂ and setting the moving speed of the stud ST to a different speed in each stroke. FIG. 2 is a connection diagram showing an example of a device in which an electric motor 5 is operated. In the figure, a control circuit 20 controls the control circuit shown in FIG. 3 by changing the output pulse of the moving speed setting unit 21b and the detector 6 into a voltage corresponding to the pulse frequency and using the frequency / voltage as a speed detection signal. A conversion circuit (F / V conversion circuit) 29, a D / A converter 23c for converting a speed command signal into an analog signal, a comparator 22b, and an electric drive by adding both outputs of the comparator 22a and the comparator 22b An adder 25 to be supplied to the machine 5 is added. In the other parts of the figure, those having the same functions as those of the examples shown in FIGS.

In the apparatus shown in FIG. 5, the moving amount setting unit 21a
The pulling amount δ ₁ , the pushing amount δ ₂ or the pulling amount δ ₃ (= δ ₁ + δ ₂ ) when pulling up from the state where the tip of the stud ST is in contact with the workpiece W, The moving amount δ ₂₁ (δ ₂₁ <δ ₃ ) before the change is preset, and the speed setting unit 21b moves the moving speeds s ₁₁ and s ₁₂ when pulling up, and the moving speeds s ₂₁ and s ₂₂ when pulling down and pushing. , S ₂₃ (s ₂₂ > s ₂₃ )
And outputs each data in response to a request from the arithmetic processing circuit 26. The contact detector 27 detects when the tip of the stud ST attached to the holder 9 comes into contact with the workpiece W and a short-circuit current flows from the auxiliary power supply 28, resets the counter 24, and Then, the contact detection signal s ₁ is sent to the arithmetic processing circuit 26 to stop the rotation of the electric motor 5. The arithmetic processing circuit 26 temporarily stores the moving amount setting signals δ ₁ , δ ₂ or δ ₃ from the setting devices 21 a and 21 b and the moving speed setting signals s ₁₁ , s ₁₂ , s ₂₁ , s ₂₂ , s ₂₃ and starts up. In accordance with signals from the command switch 2 and the contact detector 27, sequence control for sequentially outputting forward and reverse rotation command signals to the electric motor 5 is performed. For example, as in the embodiment of FIG. −
A circuit using the data is used.

The operation of the apparatus of FIG. 5 will be described with reference to the flowchart of FIG. Prior to the work, the lifting amount δ ₁ and the pushing amount δ ₂ (or the descending amount δ ₃ ), the moving amount until the speed is changed at the time of pushing (the moving amount in the first half of the pushing stroke) δ ₂₁ , and the stud ST are welded. The moving speed (first descending speed) s ₂₁ when lowering until contact with the object W, the first pulling speed s ₁₁ when pulling up from the contact state, and the moving amount from the beginning of the pushing stroke becomes δ ₂₁ . the speed of the first half, which corresponds to reach (the second lowering speed) s _22, the second half of the speed rate of the s ₂₃ and when the retainer 9 after the end of welding for pulling to the retracted position (third descending speed) of the push stroke ( the second increase rate) s ₁₂ of the diameter of the stud ST welding, set in accordance with the welding quality and the like which are materials and requirements. In addition, the holder 9 is previously set to Z _{1 in the} figure.
It is assumed that it has been moved to an appropriate position in the direction.

[0044] When the start command in this state is given by the operation switch 2, the processing unit 26 thereby to output a normal rotation signal of the speed s ₂₁ to the electric motor 5, positive by the electric motor 5 is set speed s ₂₁ by this signal rolling and drawing the lower the holder 9, i.e., is moved in the Z ₂ direction. When the tip of the stud ST comes into contact with the workpiece W due to the forward rotation of the electric motor 5, a short-circuit current flows from the auxiliary power supply 28 to this contact portion, and the contact detector 27 detects the short-circuit current, and the arithmetic processing circuit 26 detects the contact. and outputs a signal s _1. The arithmetic processing circuit 26 thereby reads out the pulling-up amount signal δ ₁ and the first pulling-up speed signal s ₁₁ , and outputs the signals via the D / A converters 23 a and 23 b.
22b.

On the other hand, the contact detection signal s ₁ is also supplied to the counter 24 to reset the counting content of the counter 24. As a result, the output of the counter 24 becomes zero, and the other inputs of the comparators 22a and 22b become zero. The output of the order comparator 22a is - [delta _1, and the addition output of the comparator 22b is a -s _11, whereby the motor 5 is reversed, upward in FIG retainers 9 at set speed s ₁₁ ( Z ₁ direction)
Move to Contact detection signal s ₁ and short-circuit between the stud ST and the welded object W is eliminated disappears by the rise of the holder 9, the counter 24 starts counting the output pulses of the detector 6 exits the reset state .

On the other hand, simultaneously with the generation of the contact detection signal s ₁ ,
Alternatively, the arithmetic processing circuit 2 is simultaneously
6 outputs an output start command signals s ₂ with respect to the welding power source E. As a result, the output of the welding power source E is supplied between the stud ST and the workpiece W, and a short-circuit current flows because the two are short-circuited. Arcs occur when leaving. Motor 5, increasing only holder 9 pulling amount [delta] ₁ that is set, both inputs of the comparator 22a is balanced, and stops at that position. During this time, the arc continues for the set time of the energization timer set by the arithmetic processing circuit 26. Signal s ₂ disappears the energization timer expires, the welding power source E is to cut off the output A - click disappears. At the same time, the arithmetic processing circuit 26 reads out the data of the pushing amount δ ₂ , the moving amount δ ₂₁ up to the speed change, the first half speed s ₂₂ and the second half speed s ₂₃ , and sends each signal to the comparators 22 a and 22 b. Are supplied to the comparators 22a, 2a.
2b, when the input signal becomes unbalanced, the motor 5 is rotated forward to move the holder 9 downward at the set speed. The amount of movement is detected by the detector 6, the counter 24 by the output signal is down-counting in contrast to the previous count value is sequentially decreased from the previous [delta] _1, when the amount of movement becomes [delta] ₂₁ the third is changed the speed setting signal to the lowering speed s _23, further continues to descend at a slower rate than the first half of the push stroke, compared to when the count value of the counter 24 becomes - [delta ₂ Strain through zero Both input signals of the device 22a are balanced and stopped. (End of push-in operation)

At this time, the stud ST first moves the workpiece W
Δ than when its tip touches _TwoOnly downward (Z_TwoOne
Direction) and the pushing amount δ_TwoIs stuck
Degree of penetration of ST. When the pushing is completed, the motor 5
Holds for the set time of the holding timer after stopping
After that, the motor 5 is again turned to the speed s₁₂Reverse the holding with
9 to Z₁Direction, stop when the upper limit is reached, and
Prepare for welding. Note that the studs are the same as in the embodiment of FIG.
After mounting ST, the holder 9₁Stop at the appropriate position in the direction
Resets the counter 24 and counts
Can be set to zero. . In this case, the stud ST
Z from start position_TwoMoves in the direction and contacts the workpiece W
Travel distance δ₀Is obtained by the detector 6, and this movement
Quantity data δ₀And set data δ₁, Δ_Two, Δ_{twenty one}And
Pull up and push in stud ST as needed
It is.

Of course, when it is necessary to change the set values of the stud pull-up amount δ ₁ , the push-in amounts δ ₂ and δ ₂₁ as in the embodiment shown in FIG. 3, the input set values to the setter 21 are changed. What is necessary is just to select suitably by a variable resistor, a push button switch, a rotary switch, etc. In FIG. 5, an F / V conversion circuit for converting the frequency of the output pulse of the movement amount detector 6 into a voltage is used as a means for detecting the movement speed. The tachogenerator may be coupled so that a voltage proportional to the speed of movement is obtained directly. In this case, since the speed detection signal is obtained as an analog signal, the F / V converter used for the speed detection circuit in the apparatus of FIG. 5 becomes unnecessary, and the output of the tachogenerator can be used as it is or through a suitable amplifier or attenuator. What is necessary is just to input into 22b.

Here, the set values s ₁₁ , s ₁₂ , s of the moving speed
₂₁ not about to s ₂₃ will be described. First lowering speed setpoint s ₂₁ because the tip by first lowering the stud ST was set in the holding device 9 is intended to determine the moving speed until the contact with the object to be welded W, shock at the time of contact Needs to be set relatively late to reduce At this time, it is also necessary to reduce the force generated by the driving device to prevent damage at the time of contact. For this purpose, when the driving machine is constituted by an electric motor, the supply current may be limited so as to limit the torque (or thrust) generated by the motor.

The first rising speed set value s ₁₁ is set to a high speed within a range in which the arc generated at the start of the rising due to the short-circuit current supplied from the welding power source E at the time of contact grows sufficiently and the arc does not break. The speed at the time of lowering after completion of the pulling may be high until the tip of the stud ST comes into contact with the molten metal pool of the work to be welded by the arc. The generated molten metal portion is prevented from scattering due to impact. For this purpose, the second step of determining the speed of the first half of the stroke (from the previous pulling position to a position lowered by δ ₂₁ ) at the time of pushing is performed.
Lowering speed setpoint s ₂₂ of faster, third lowering speed setpoint s ₂₃ that determines the speed of the latter half of the stroke is set slower. Furthermore, since the time of pulling after welding completion not at all affect the weld quality second rising speed s ₁₂ of attained a reduction in tact time by setting a high speed without affecting the durability of the drive motor system. To illustrate the relationship of each set speed, s ₁₁
The _{<s 12, s 22> s} 23 >> s 21. The ascent speed s ₁₁
And s ₁₂ may be substantially the same value, so can be performed even approximately welding as equivalence opposite only sign to the s ₂₂ and s _11, 3 kinds of the signal s ₁₁ is a set value when, s _21, s ₂₃ Is good. _{(S 11 = s 12 = -s} 22)

[0051] Further speed setting during indentation well as signals that change in the number stages of polygonal line in addition to the two stages as signal s ₂₂ and s ₂₃ as described above, or from pushing the start to push complete The setting signal may be determined so that the interval changes continuously from high speed to substantially zero. In these cases, the speed setting signal s _2n indicates the amount of movement δ of the holder 9 at the time of pushing.
_2n , the function s _2n = f (δ _2n ) of the moving amount may be determined. Further, these speed setting signals may be prepared in advance by preparing several kinds of signals having different changes which are programmed in advance, and may be selected according to the material and diameter of the stud to be welded, required welding quality and the like.

In FIGS. 3 and 5, the stud ST is moved after the stud is mounted, and the contact state between the tip of the stud ST and the workpiece W is electrically detected. Regardless of the position of the previous holder 9 or the setting position of the abutment member 11 with respect to the gun body 1, it is possible to set the stud ST up and down after contact between the tip of the stud ST and the workpiece W as desired. It can be implemented automatically to be in a state.

Further, the tip of the stud ST and the workpiece W
Abutment can be performed manually as described below. That is, the gun body 1 on which the stud ST is mounted,
When the stud ST is disposed as shown in FIG. 1 through the contact member 11 that comes into contact with the workpiece W, the tip end of the stud ST is Z _1.
When the rotary member 3 is rotatable by providing the motor 5 itself free of rotation or providing an appropriate clutch in the drive system,
The holder 9 and stud ST operator in manually moved in the Z ₂ direction, the leading end of each of the stud ST and the contact member 11 can be brought into contact with the welding subject W.

On the other hand, when mounting the stud ST, when the tip of the stud ST is positioned at Z ₂ direction side than the tip of the contact member 11 is in a state of being rotatable rotary member 3 in the same manner as described above, The operator holds the holder 101 of the gun body 1.
Gripping the, while abutting the front end of the stud ST to be welded W, presses the gun body 1 in the Z ₂ direction, the stud S
The tip of T and the tip of the contact member 11 can be brought into contact with the workpiece W. As described above, when the respective tips of the stud ST and the contact member 11 are brought into contact with the workpiece W by human power, the content of the output counter 24 of the detector 6 is set to zero in this contact state. By resetting, the stud ST can be raised and lowered based on the set values preset in the setting devices 21a and 21b.

In the embodiment shown in FIGS. 3 and 5, the output of the setting devices 21a and 21b and the output of the detector 6 of the electric motor 5 are compared and controlled by the control circuit 20. -Because of the feedback control, it is possible to perform arc stud welding with a high performance set value. Of course, the present invention is not limited to the above, and the arc stud welding is performed by controlling the so-called open loop system based on the set values of the setting devices 21a and 21b electrically connected to the electric motor 5. You can do it.

Next, a case where a so-called ferrule F that covers the tip of the stud ST is used will be described. In FIGS. 7 to 10 of the second embodiment, 11, 11
Is is bridged via bridge members 111 at the ends of the Z ₂ direction, at the contact member into contact with one or more locations of the positions to be welded W, in the illustrated case, the object to be welded W 2 Point contact member 1
13, 114 are provided. The bridging member 111
Is provided with a notch 112 for pressing the shoulder of the ferrule. Further, Z ₁ direction of the end portion of the contact member 11, 11 is supported on the gun body 1. Preferably,
Z ₁ direction end positions gun body of the contact member 11, 11 1
Are supported so that the position can be freely set in the Z direction. Reference numeral 12 denotes a rotary shaft rotatably supported by the gun body 1 via bearings 13 and 13, and is provided with a male screw 121a, most preferably a ball screw. End of the Z ₁ direction of the rotary shaft 12 is coupled to the electric motor 5 for rotating through the appropriate reducer. A detector 6 for detecting a driving amount of the electric motor 5 is connected to the electric motor 5. 14 is the contact member 1
A frame body that is movable in the Z-direction while being positioned by the first and the eleventh, and a female screw 141 that is screwed to the male screw 121a of the rotating shaft 12, optimally a ball nut, and the contact members 11, 11
Guides 142, 142 that slide along are provided. The holding member 9 for holding the stud ST is provided on the frame body 14.

In the second embodiment, the contact member 11
7 and FIG. 9 when the tip of
As shown in FIG. 10, the ferrule F is pressed in the vicinity of the notch 112 of the contact member 11. It should be noted that a setting device for presetting the pulling amount, pulling amount or moving speed of the stud ST is provided, and a control circuit 2 similar to that shown in FIG.
The configuration of 0 is the same as in the first embodiment. The arc stud welding operation is exactly the same as that of the first embodiment except for the matters relating to the ferrule, so that the description of the operation and the modification are omitted. In addition,
In the first and second embodiments, the stud welding start signal is provided by providing a dedicated operation switch on the gun body 1 or a foot-operated operation box, or by providing the gun body 11 with a changeover switch in addition to the operation switch 2. By providing a plurality of switches in a foot-operated or manual operation-type operation box without providing operation switches on the gun body 1 or using a timer together with the operation of the operation switch 2, Can be implemented. Of course, in the second embodiment, the notch 112 may be provided at the tip of the contact member 11 or may be omitted depending on whether or not the ferrule is used.

As described above, in the first and second embodiments,
Although the semi-automatic arc stud welding has been described, the same applies to the fully automatic arc stud welding. That is, in a fully automatic stud welding apparatus, at the time of stud welding, the position of the tip support member supporting the stud welding gun is moved in the Z direction by using, for example, a Z-direction drive mechanism provided as the welding apparatus. If this is attempted, the vibration of the welding device accompanying the drive of the large drive mechanism will be transmitted to the stud welding gun, or the stud will be pulled up due to backlash or response delay of the large drive mechanism. The amount and the pushing amount cannot be set to a desired state.

For this reason, even in the fully automatic arc stud welding apparatus, the gun body positioned with respect to the work to be welded, and the holder provided on the gun body for holding the stud are arranged in the longitudinal direction of the stud. A stud welding machine having a holder driving mechanism for displacing the position, an electric driving machine for moving the holding tool in the longitudinal direction of the stud, and an electric drive connected to the driving machine, An arc stud welding machine provided with a control circuit capable of presetting a displacement amount and a speed is used.

In this case, as shown in FIG. 11, for example, in an arc stud welding apparatus 40 provided with a drive mechanism 41 in the Z direction and an appropriate drive mechanism, for example, a turning mechanism 42, the drive is performed by the drive mechanism 41. Tip support member 4
11, the gun body 1 of the stud welding gun 30 is integrally supported. When the ferrule F is used, the stud welding gun 30 has a stud welding gun 3 shown in FIGS.
0 is used. Of course, the setting conditions of the stud ST lifting amount δ ₁ , pulling amount δ ₂ , δ ₂₁ , δ ₃ and moving speeds s ₁₁ , s ₁₂ , s ₂₁ to s ₂₃ are the same as in the previous embodiment. .
On the other hand, when the ferrule F is not used, the stud welding gun 30 is obtained by removing the contact member 11 in FIG. 1 or by using the members 113 and 114 that contact the workpiece W in FIG. The deleted one is used.

As described above, as the stud welding gun 30,
A case in which a member abutting on the workpiece W is not provided will be described. In FIG. 11, when the driving mechanism 41 of the welding device 40 positions the distal end support member 411 at the welding position, the distal end of the stud ST is connected to the distal end. Preset values corresponding to the stud pull-up amounts δ ₁ and the pull-down amounts δ ₂ , δ ₂₁ , δ ₃ by driving the holder 9 in the stud welding gun 30 are set based on the state of contact with the workpiece W. be able to. In this case, in advance by applying a voltage between the stud ST and the weld object W, and the tip support member 411 and the stud welding gun 30 is driven in the Z ₂ direction by the drive mechanism 41, the stud ST and welded The drive mechanism 41 is stopped when the object W is electrically short-circuited.

In order to finely position the stud ST, the tip support member 411 is fixed at an appropriate position by the drive mechanism 41, and then the stud holder 9 is moved to the Z position by the drive mechanism provided on the stud welding gun 30. It is preferable to drive in _two directions to detect the contact between the stud ST and the workpiece W by an electric short circuit. Contact between the tip of the stud ST and the workpiece W is automatically performed, and, as shown in FIG. 3 or FIG. 6, arc stud welding is automatically performed according to the set value after the contact.

In each of the above embodiments, an example has been described in which both the stud pull-up amount and the push-in amount are preset to control the entire stroke of the stud movement. Is preset, and the pressing operation is performed without performing the position control. In this case, at the time of pressing, the stud is pressed at a predetermined pressing force, so that the stud stops at a position where the reaction force from the welded portion and the pressing force are balanced. In this case, since the pulling amount that most affects the welding is accurately controlled, the amount of heat supplied to the welded portion is accurately controlled, and the stud and the amount of melting of the workpiece are accurate. Therefore, when the stud is pushed into the fusion portion with a predetermined pushing force, the stop position can be almost fixed. Of course, at the time of pushing, the moving speed of the stud is changed stepwise or continuously in the middle of the pushing process, so that the stud is substantially in contact with the work to be welded before the pulling-up at the initial pushing speed. If the speed after being pushed into the vicinity of the contact position is controlled to be small, the tact time at the time of pushing is shortened and high-quality welding that does not scatter the molten metal can be performed.

Further, in the present invention, since the driving mechanism of the holder driving mechanism is controlled by an electric driving machine, fine position control and variable control of the driving force can be easily performed at low cost. Of course, in arc stud welding,
Since the amount of pulling or pushing of the stud is variously changed, and it is necessary to finely adjust the amount of pulling or pushing, so-called pressure fluid type driving machine such as hydraulic or compressed air is used. In addition, it is not practical to make the structure finely adjustable in accordance with the amount of pull-up or push-in which is variously changed, because not only the structure becomes extremely complicated, but also the temperature rises.

In addition to the moving amount and the moving speed, it is possible to control so that the driving force immediately before the completion of the pushing into the molten portion becomes smaller or larger than the driving force in other portions. By this control, a freely welded portion can be selected.

Further, as a detector of the amount of movement of the holder moved by the driving device, an appropriate detector such as a rotary encoder, a potentiometer, and a differential transformer can be freely selected.

[0067]

As is apparent from the above description, the arc stud welding machine according to the first and second inventions is particularly suitable for:
An electric driving device for moving the stud holder in the longitudinal direction of the stud, a moving amount setting device electrically connected to the driving device and capable of presetting at least a stud lifting amount; and a moving amount setting device. Since a drive control circuit for displacing the holder in accordance with the set value of the holder is provided, a mechanical positioning mechanism as in the prior art is not required, and the structure of the Arkstad welding machine is simplified and the cost is reduced. In addition to being able to be manufactured, unlike the conventional case, the welding quality is not degraded due to the wear of the contact member or the loosening of the positioning mechanism, and the desired arc stud welding is performed by pure electric control for each stud welding. It can be performed reliably, and at least the work of adjusting the lifting amount of the stud before welding can be performed by selecting the input set value to the setting device. In comparison with the case of mechanically adjusting the gun components can be performed quickly and very easily adjusting operation.

Further, since the position of the gun body 1 in the Z direction can be freely set by adjusting the position of the contact member 11 prior to welding, the arc stud welding can be performed efficiently by setting the posture suitable for the worker. be able to. Of course, it is welded object W ₁ protruding Z ₁ direction in the vicinity of the welding position is also present, the gun body 1 to adjust the abutting member 11 so as to be positioned in the Z ₁ direction than welded object W ₁ Thereby, desired arc stud welding can be performed.

Further, the arc stud welding machine according to the third and fourth aspects of the present invention includes an electric driving machine for moving the stud holding tool in the longitudinal direction of the stud, and a holding tool moved by the driving machine. A movement amount detector for detecting the movement amount of
When at least the stud lifting amount can be preset and the setting value of this movement amount setting device and the detection value of the movement amount detector are input and the holder reaches the setting value of the movement amount setting device Since the servo control circuit for stopping the movement of the holder is provided, in addition to the effects of the first and second aspects of the invention, an arc stud according to a high-performance set value is obtained by electric control of a feedback system. Welding can be performed.

Further, the arc stud welding machine according to the fifth and sixth aspects of the present invention includes an electric driving machine for moving the stud holding tool in the longitudinal direction of the stud, and a holding tool moved by the driving machine. A movement amount detector for detecting the movement amount of
A movement amount setting unit at least in which the stud lifting amount can be preset, and a setting value of the setting unit and a detection value of the detector as inputs, and the holding unit holds the setting value when the holding unit reaches the setting value of the setting unit. When the stud is pushed into the vicinity of the contact position between the stud and the workpiece before pulling up, the speed is lower than the initial speed of the stud during the pushing. In addition to the effects of the third and fourth inventions, a desired arc stud welding can be performed irrespective of the variation of the stud length, since the servo control circuit controlled so that Tact time at the time of indentation can be shortened, and high-quality welding that does not scatter molten metal can be performed.

[Brief description of the drawings]

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

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a connection diagram illustrating an example of a control circuit used in FIG.

FIG. 4 is a flowchart for explaining the operation of the control circuit of FIG. 3;

FIG. 5 is a connection diagram showing another example of the control circuit used in FIG. 1;

FIG. 6 is a flowchart for explaining the operation of the control circuit of FIG. 5;

FIG. 7 is a front sectional view showing a second embodiment of the present invention.

8 is a sectional view taken along line VIII-VIII in FIG. 7;

9 is a sectional view taken along line IX-IX in FIG. 7;

10 is a sectional view taken along the line XX in FIG. 7;

FIG. 11 is a front view showing a third embodiment of the present invention.

FIG. 12 is a front sectional view showing a conventional example.

FIG. 13 is an explanatory diagram of a state of general arc stud welding.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gun main body 2 Operation switch 5 Electric drive 6 Detector 9 Stud holder 11 Contact member 20 Control circuit 21a Moving amount setting device 21b Speed setting device 22a, 22b Comparator 23a, 23b, 23c D / A conversion Instrument 26 Arithmetic processing circuit 27 Contact detector 28 Auxiliary power supply 29 F / V converter 30 Stud welding gun E Welding power supply ST Stud F Ferrule

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B23K 9/20

Claims (5)

(57) [Claims] A gun body positioned with respect to an object to be welded , and a holder provided on the gun body for holding a stud, wherein an arc is generated at a contact position between the object to be welded and the stud. An arc stud welding machine having a holder driving mechanism for at least displacing a lifted state for pushing and a pushing state after melting, the gun being brought into contact with an object to be welded.
A contact member for positioning the main body and near the welding position
There is a work piece protruding in the long axis direction of the stud beside
Set the distance so that the gun body does not interfere with the workpiece
A contact member position adjusting mechanism, an electric driving device that moves the holding tool in the long axis direction of the stud, a movement amount detector that detects a movement amount of the holding tool moved by the driving device,
A moving amount setting device capable of presetting at least a pull-up amount of the stud; a speed setting device capable of presetting at least a moving speed when the stud is pushed; a setting value of at least the moving amount setting device; and the moving amount detector An arc stud welding machine having a servo control circuit that receives the detected value of the speed setting device and the set value of the speed setting device as input and controls the amount and speed of movement of the holder when the holder is moved so as to match the set values. . Wherein said speed setting instrument, claims a setter for outputting a set value of the two stages that slow the latter half than the first half of the push stroke of at least the stud
2. The arc stud welding machine according to 1. 3. The arc stud welding machine according to claim 2, wherein the speed setter is a setter that outputs a signal that the speed is continuously reduced at least in the latter half of the stud pushing stroke. 4. The speed setting device is a setting device that outputs a signal that changes in accordance with the amount of displacement of the holder, and the servo control circuit includes a setting value of the movement amount setting device and the speed setting device. A servo control circuit that controls a moving amount and a speed by inputting a set value of the moving amount detector and a detection value of the moving amount detector.
The arc stud welding machine according to any one of claims 1 to 3 . Wherein said movement amount setter claim 1乃 pulling amount and the amount of pushing the stud are both presettable
The arc stud welding machine according to any one of claims 4 to 5 .