JPH05245643A - Arc stud welding machine - Google Patents

Abstract

PURPOSE:To quickly and easily adjust the quantity of pulling-out of a stud by arranging a moving quantity setting device capable of presetting the quantity of pulling-out of the stud and a drive control circuit to change the position of a holder according to a set value of the moving quantity setting device. CONSTITUTION:The moving quantity setting device 21a presets the quantity of pulling-out at the time of pulling out, the quantity of pressing-in or the quantity of pulling-down from a state with the tip of the stud ST in contact with materials W to be welded and outputs respective data according to requirements from an arithmetic processing circuit. A contact detector detects when the tip of the stud ST fitted on the holder 9 comes into contact with the materials W to be welded and a short-circuit current flows from an auxiliary power source, resets an up-and-down counter and sends a contact and detection signal to the arithmetic processing circuit to stop rotation of a motor 5. The arithmetic processing circuit stores primarily a set signal from the setting device 21a and further, executes sequence control for the motor 5 according to signals from a switch 2 for a starting command and the contact detector.

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 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 abutting the stud and the object to be welded, the stud is pulled up by a predetermined amount to generate an arc between the stud and the object to be welded, and after melting both members by this arc, the stud is welded to the object to be welded. The present invention relates to an improvement of a full-automatic and semi-automatic arc stud welding machine in which welding is performed by pushing it to the 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. 60-45989.

That is, in FIG. 12, 51 is a gun body 5.
A stud ST holder 9 is attached to one end of the shaft 51 in the Z ₂ direction via an electrically insulating material. .. 5
Reference numeral 3 denotes a compression spring arranged between a collar portion 510 fixed to the shaft 51 and a central protruding portion 521 provided substantially at the center of the cylindrical portion of the gun body 52, and 54 surrounds the periphery of the shaft 51. , 55 is an electromagnetic coil arranged in the outer core 54, 56 is a lid core closing the outer core 54,
Reference numeral 57 denotes a movable iron core that penetrates through the holes of the outer iron core 54 and the electromagnetic coil 55, and a through hole for allowing the shaft 51 to movably penetrate is formed in a substantially axial center portion of the movable iron core 57. 5
8 is a movable iron core 57 having a constant width in the circumferential direction.
This arm 58 is an arm protruding from the axial end of the
A claw 581 is provided at the end in the Z ₂ direction. A disc-shaped lifting ring 59 is loosely fitted to the shaft 51, and the lifting ring 59 is pressed against a seat portion 522 provided on the central protruding portion 521 by a compression spring 61 provided between the shaft 51 and the movable iron core 57. ing. For the claw 581, the arm 58 is Z
_It is provided so as to engage with the lifting ring 59 when displaced in _one direction, and is pressed toward the central projecting portion 521 by a compression spring 62 provided between the armoring iron core 54 and the arm 58. Reference numeral 63 denotes a stopper fitting screwed to the lid iron core 56 so that the position in the Z direction can be freely adjusted, and 64 is arranged so as to penetrate the substantially axial center portion of the stopper fitting 63 so as to be movable in the Z direction. The reading bar has a scale in the axial direction. Reference numeral 11 is a contact member disposed on the side surface of the gun body 52 at the end in the Z ₂ direction so as to be substantially parallel to the shaft 51. The contact member 11 is positioned in the Z direction by an appropriate fastener. Adjustably fastened.

In the stud gun shown in FIG. 12, when the electromagnetic coil 55 is in a non-excited state, the movable iron core 57 is used.
And the lifting ring 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 distance is maintained in the Z direction between the claw 581 of the arm 58 and the lifting ring 59. Further, when the electromagnetic coil 55 is in the non-excited state, the collar portion 510 is pressed in the Z ₂ direction by the compression spring 53, and the collar portion 510 and the lower plate 523 of the gun body 52 are in contact with each other. In this state, the holder 9 has a length L, for example.
The stud ST of _{No. 1} is attached, and the abutment member 11 is operated by operating the tightening tool so that the tip of the stud ST projects in the Z ₂ direction from the tip of the abutment member 11, for example, by δ _2.
Adjust the length of. By the way, when the electromagnetic coil 55 is excited in the state shown in FIG. 12, the movable iron core 57 is pulled up in the Z ₁ direction until it abuts on 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
Contacts a part of the circumference of the lifting ring 59 to incline the lifting ring 59, so that the round hole of the lifting ring 59 through which the shaft 51 penetrates contacts the outer peripheral surface of the shaft 51, and 51 and the lifting ring 59 are connected. Therefore, when the movable iron core 57 is pulled up in the Z ₁ direction, the pawl 581, the lifting ring 59 and the shaft 51 are immediately pulled up together in the Z ₁ direction, and the reading bar 64 also moves in the Z ₁ direction along with the shaft 51. Moving. Therefore, when the electromagnetic coil 55 is in the non-excited state, the stopper fitting 63 is screwed in the Z ₂ direction to bring the stopper fitting 63 into contact with the movable iron core 57, and thereafter, while checking the scale of the reading bar 64. The stopper fitting 63 is screwed in the Z ₁ direction by a distance δ ₁ to position the stopper fitting 63.

After the above adjustment, in FIG. 12, the length L ₁ held by the holder 9 with the electromagnetic coil 55 in a non-excited state is shown.
The gun body 52 is pressed in the Z ₂ direction while the tip of the stud ST of No. 1 is brought into contact with the workpiece W. In a state where the respective tips of the stud ST and the contact member 11 are in contact with the workpiece W (FIG. 13A), the flange portion 510 of the shaft 51 and the lower plate 5 are in contact with each other.
It is separated from 23 by a distance δ ₂ . When the electromagnetic coil 55 is energized in this state, the movable iron core 57 is pulled up in the Z ₁ direction, and along with the position displacement of the movable iron core 57, the pawl 581, the lifting ring 59, and the shaft 51 are integrated into Z _1.
In the direction by a distance δ ₁ . This state is shown in FIG.
It is indicated by (b). When the arc generated between the stud ST and the object to be welded W is appropriately maintained in the state of FIG. 13B, when the energization of the electromagnetic coil 55 is cut off, the shaft 51 and the holder 9 are separated. It is urged in the Z ₂ direction by the spring force of the compression spring 53. That is, as shown in FIG.
The stud ST and the holder 9 are pulled down in the Z ₂ direction by a distance δ ₃ (= δ ₁ + δ ₂ ) from the state shown in FIG. After all, 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 are in contact with the workpiece W (FIG. 13A), and the pushing amount of the stud ST is large. δ ₂ welding is performed.

[0006]

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

That is, as shown in FIG. 12, when the collar portion 510 of the shaft 51 is biased in the Z ₂ direction by the compression spring 53 and the collar portion 510 and the lower plate 523 are in contact with each other, for example, the length L The stud ST of _{No. 1} is attached to the holder 9, and the tip of the contact member 11 is Z ₁ from the tip of the stud ST.
The position of the contact member 11 is adjusted so that the contact members 11 are spaced apart in the direction by, for example, the interval δ ₂ . Therefore,
If the values of the stud length L ₁ and the pushing amount δ ₂ are selected, the position of the gun body 52 with respect to the workpiece W, for example,
The distance H ₁₀ between the work piece W and the lower end of the gun body 52 and the distance H ₂₀ between the work piece W and the holder of the gun body 52 are unique unless the components of the welding gun are replaced with different lengths. Is decided. Therefore, the holder 9 near the welding position
If the workpiece W ₁ is present in a region where it does not hinder the movement of the workpiece, but can interfere with the end of the gun body 52, the gun is welded when the height of the workpiece W ₁ is H ₁₀ or more. Since the main body 52 and the workpiece W ₁ come into contact with each other, the stud length L
_No welding of ₁ . That is, when the object to be welded W ₁ is present in the above-mentioned region, there is a problem that the length of the stud that can be welded is limited to a specific dimension or more. Further, for example, in a so-called semi-automatic arc stud welding operation in which an operator grips and holds the holder of the gun body 52, when the stud length L ₁ and the pushing amount δ ₂ are selected as described above, the welding target Since the distance H ₂₀ between the object W and the holder is determined, the work efficiency is poor.

On the other hand, in arc stud welding, the stud pull-up amount δ ₁ and the stud push-in amount δ ₂ must be appropriately selected depending on the stud material, diameter, welding conditions and the like. In particular, the stud size and the length of the arc that accompanies the pulling up of the stud have a delicate correlation, so it is necessary to maintain the pulling amount of the stud to a desired value. Therefore, in the conventional arc stud welding gun shown in FIG. 12, the pull-up amount δ ₁ and the push-in amount δ ₂ of the stud ST are visually adjusted while appropriately mechanically operating the components manually. Was there. Of course, if a mechanical positioning mechanism is provided on the arc stud welding gun, not only will the structure become complicated and the price will rise, but also manual mechanical adjustment work will be troublesome, and misadjustment due to eye measurement error will occur. Therefore, there is a problem that the welding quality is deteriorated.
Of course, in the welding operation, the pull-up amount δ ₁ and the push-in amount δ ₂ are changed every time the target stud size and welding conditions are changed.
The above-mentioned problem was magnified because the adjustment work of (1) had to be performed.

Further, in the arc stud welding work, since more than 700 studs are normally welded per day, repetitive force frequently acts on each part of the stud welding gun. Therefore, when the positioning of the mechanical adjustment part is uncertain, or when parts are worn, the pull-up amount δ ₁ and the push-in amount δ ₂
However, there is a problem that the welding quality deteriorates.

Furthermore, in the above-mentioned conventional arc stud welding gun, when stud welding of tens of thousands or more is performed, the fume generated during welding is slightly subdivided into the gun body 52.
Of the lifting ring 59 that flows into the interior of the shaft 51 and gradually adheres to the surfaces of the shaft 51 and the lifting ring 59 in the form of oil and fat, and abuts when the shaft 51 is pulled up.
Parts gradually wear. Therefore, when the stud ST is pulled up, an irregular sliding state occurs between the lifting ring 59 and the shaft 51, and in order to eliminate this sliding state, the lifting ring 59 is appropriately replaced with a new one. Or
It was necessary to remove the adhered oil and fat.

Further, in FIG. 12, the length is L ₁ -ΔL
When the stud ST of No. 1 is used, as shown in FIG. 13 (a), when the tips of the stud ST and the contact member 11 are in contact with the workpiece W, the flange portion 510 and the lower portion of the shaft 51 are The plate 523 is more than the predetermined distance δ ₂ by Δ.
It becomes smaller by L. That is, although the stud pull-up amount δ ₁ is as desired, the stud push-in amount is δ ₂ −ΔL, and thus the push-in amount may be insufficient.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a gun main body for a workpiece to be welded even when the length L _{1 of the} stud and the pushing amount δ ₂ are selected as desired values. The position can be set freely, and at least the pulling amount of the stud can be set accurately and freely purely and electrically without the need for mechanical adjustment of the components. It is an object of the present invention to provide an arc stud welding machine capable of changing the moving speed, in particular, the speed so that an optimum welding result can be obtained during the pushing stroke by electrically moving the stud holder.

[0013]

SUMMARY OF THE INVENTION The first aspect of the present invention is to provide a gun main body that is positioned with respect to an object to be welded, a holder that is disposed on the gun main body, and that holds a stud, to the object to be welded and the stud. The present invention is applied to an arc stud welding machine having a holding member drive mechanism that displaces at least the pulled-up state for generating an arc with respect to the contact position with and the pushed-in state after melting. The feature is that an electric drive machine that moves the holder in the longitudinal direction of the stud and a movement amount that is electrically connected to the drive machine and at least the pulling amount of the stud can be preset. The setting device and the driving machine control circuit for displacing the holder according to the set value of the movement amount setting device are arranged.

The second aspect of the present invention is directed to a gun body and a holder for holding the stud, which is arranged on the gun body, for generating an arc with respect to a contact position between the object to be welded and the stud. An operator has a holder drive mechanism that displaces at least a position between the upper state and the pushed state after melting, and an abutting member that abuts on an object to be welded to position the gun body. It is applied to an arc stud welding machine that welds while holding a holder. The feature is that an electric drive machine that moves the holder in the longitudinal direction of the stud and a movement amount that is electrically connected to the drive machine and at least the pulling amount of the stud can be preset. The setting device and the driving machine control circuit for displacing the holder according to the set value of the movement amount setting device are arranged.

According to a third aspect of the present invention, a gun main body positioned with respect to an object to be welded and a holder arranged on the gun main body for 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 holding member drive mechanism that displaces at least a pulled-up state for generating an arc and a pushed-in state after melting. The feature is that an electric drive machine that moves the holder in the longitudinal direction of the stud, a movement amount detector that detects a movement amount of the holder moved by the drive machine, and at least the stud. When the holding amount reaches the set value of the movement amount setter by inputting the set value of the movement amount setter and the detected value of the movement amount detector And a servo control circuit for stopping the movement of the holder.

A fourth aspect of the present invention is directed to a gun main body and a holder arranged on the gun main body for holding a stud for generating an arc with respect to a contact position between an object to be welded and the stud. An operator has a holder drive mechanism that displaces at least a position between the upper state and the pushed state after melting, and an abutting member that abuts on an object to be welded to position the gun body. It is applied to an arc stud welding machine that welds while holding a holder. The feature is that an electric drive machine that moves the holder in the longitudinal direction of the stud, a movement amount detector that detects a movement amount of the holder moved by the drive machine, and at least the stud. When the holding amount reaches the set value of the movement amount setter by inputting the set value of the movement amount setter and the detected value of the movement amount detector And a servo control circuit for stopping the movement of the holder.

According to a fifth aspect of the present invention, a gun main body positioned with respect to an object to be welded and a holder arranged on the gun main body for 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 holding member drive mechanism that displaces at least a pulled-up state for generating an arc and a pushed-in state after melting. The feature is that in the third invention, a speed setter for setting the speed at the time of pushing the stud is added, and the servo control circuit performs both position control and speed control.
It uses a control circuit.

A sixth aspect of the present invention is directed to a gun main body and a holding member arranged on the gun main body for holding a stud for generating an arc with respect to a contact position between an object to be welded and the stud. An operator has a holder drive mechanism that displaces at least a position between the upper state and the pushed state after melting, and an abutting member that abuts on an object to be welded to position the gun body. It is applied to an arc stud welding machine that welds while holding a holder. The feature is that in the fourth invention, a speed setter for setting the speed at the time of pushing the stud is added, and a servo control circuit performs both position control and speed control. It uses a control circuit.

In a seventh aspect of the present invention, in the fifth and sixth aspects of the invention, the setting signal of the speed setter is set to two stages, and the latter half of the speed setting value of the first half of the pushing stroke is set when the stud is pushed. It is characterized in that the speed setting value of is set to a slow setting value.

In the eighth invention, in the fifth and sixth inventions, the set value of the speed setter is a signal that continuously changes, and the latter half of the stud pushing stroke is gradually changed from the first half. The feature is that the set value becomes slower.

The ninth invention is characterized in that, in the fifth and sixth inventions, the speed setting signal is determined in relation to the moving amount.

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

[0023]

The present invention will be described in detail below with reference to the embodiments shown in the drawings. For example, the semi-automatic arc stud welding will be described. In FIGS. 1 to 3, which is the first embodiment, 1 is a gun body having a holder 101 to be gripped by an operator. An operation switch 2 for welding work is provided, and various cables are appropriately supported. Reference numeral 3 denotes a rotary member rotatably supported by the gun body 1 via a bearing 4.4. A female screw 301, optimally a so-called ball nut, is integrated with the rotary member 3 at the shaft core of the rotary member 3. It is installed in. 5
Is an electric drive machine supported by the gun body 1, for example, a rotary electric machine. The output shaft of the electric machine 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 is a detector for detecting the drive amount of the electric motor 5, for example, a rotary encoder.

Reference numeral 7 denotes a male screw 701 which is screwed into the female screw 301 of the rotary member 3, and optimally a protective shaft provided with a ball screw, and at least one axial groove 702 is provided outside the protective shaft 7. Are arranged. Reference numeral 8 is a locking member supported by the gun body 1, for example, a sliding key.
The holding shaft 7 is movably supported by the gun body 1 only in the axial direction, that is, in the Z direction. A holding tool 9 holds the stud ST, and is supported by the holding shaft 7 via an appropriate electrical insulating member. Reference numeral 11 is an abutting member for abutting against the object W to be welded to position the gun body 1. In the case shown in the drawing, the abutting member 11 is the gun body 1
It is supported by the gun body 1 so that the position in the major axis direction of the, i.e., the Z direction can be set freely. Reference numeral 20 is a control circuit of the driving machine 5 for displacing the holder 9, and reference numeral 21a is a movement amount setter for setting 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 uses the movement amount setting device 21a.
The set value of 1 and the output of the movement amount detector 6 are input, and the holder 9 is positioned at a position where both inputs match. The semi-automatic arc stud welding gun 30 is configured by the above 1 to 11, and the servo control circuit that controls the movement amount of the holder 9 is configured by the movement amount setting device 21a, the movement amount detector 6, and the driving machine control circuit 20. This welding gun 30, a servo control circuit, and a welding power source (not shown) constitute a stud welding machine.

Next, a semi-automatic arc stud welding operation using the stud welding gun 30 will be described. Figure 1
First, at a position where 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 by 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 Is moved up to. That is, the operation of the operation switch 2 drives 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 shaft 7 is screwed into the female screw 301 of the rotating member 3. The shaft 7 is moved in the Z ₁ direction.

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

By the way, if the stud ST is specified to have a desired material and size, the stud pull-up amount δ ₁ and the stud push-in amount δ ₂ are known as welding data. On the other hand, the resolution of the rotation amount 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 movement amount of the holder 9 with respect to the unit detection value of the detector 6 is the stud welding gun 30.
Is known as Therefore, with reference to the state in which the tip of the stud ST and the tip of the abutting member 11 are in contact with the workpiece W, the pull-up amount δ ₁ and the pull-down amount δ ₃ (= the pull-up amount δ
Set the value corresponding to ₁ + pushing amount δ ₂ ) as the preset value. Of course, as described above, since the movement amount of the holder 9 with respect to the unit detection value of the detector 6 is known, 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 is the detection pulse equivalent value of the detector 6, Δ1,
It is possible to preset as Δ3 or Δ2, or set the pull-up amount δ ₁ and the pull-down amount δ ₃ or the push-in amount δ ₂ and convert them into detection pulse equivalent values Δ1, Δ3 or Δ2 in the setter 21. it can.

As described above, after the tip of the stud ST contacts the object W to be welded, the stud ST and the holder 9 can be moved in the Z ₁ direction automatically or by appropriate switch operation. 5 is reversed. That is, the drive amount of the electric motor 5 is detected by the detector 6, and the electric motor 5 is reversely driven until the detection signal reaches the pulling amount δ ₁ . The electric motor 5 is stopped when the lifting amount of the stud ST reaches δ ₁ . The output of the welding power source is the same as in the conventional case, and after the stud ST contacts the workpiece W, the position displacement of the stud ST in the Z ₁ direction starts at the same time.
Alternatively, the arc is generated between the stud ST and the workpiece W at the moment when the stud ST is supplied just before it is started and pulled up from the workpiece W.

The supply of the welding current is interrupted immediately after the amount of pull-up of the stud ST reaches δ ₁ after the above, or after that in consideration of the molten state of the stud ST and the workpiece W. After that, the electric motor 5 is driven in the normal direction so that the stud ST and the holder 9 move in the Z ₂ direction, and the stud ST is moved in the Z ₂ direction by the set amount δ ₃ by the detector 6 and the control circuit. , Arc stud welding is completed. Of course, in this case, the pushing amount of the stud ST into the workpiece W is δ ₂ (= δ ₃ −δ ₁ ). After welding
The holder 9 is appropriately moved in the Z ₁ direction automatically or by operating the operation switch 2 to complete the welding work for one cycle. The holder 9 may be moved in the Z ₁ direction after welding, and may be carried out before or after the next stud mounting.

Next, an example of a control circuit for automatically adjusting the pulling amount δ ₁ and the pushing amount δ ₂ will be described. Figure 3
FIG. 4 is a connection diagram showing an example of a device in which the electric motor 5 is automatically operated so that the pulling amount δ ₁ and the pushing amount δ ₂ are preset so as to have these set values. In the figure, the control circuit 20 includes a movement amount setter 21a, a comparator 22a, D / A converters 23a and 23b, an up / down counter 24, an arithmetic processing circuit 26, a contact detector between the stud ST and the workpiece W. 27 and an auxiliary power supply 28. Further, E is a welding power source to which electric power is supplied from the 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 of the example shown in FIG.

In the apparatus of FIG. 3, the movement amount setting device 21a
Is calculated by presetting the pull-up amount δ ₁ , the push-in amount δ ₂ or the pull-down amount δ ₃ (= δ ₁ + δ ₂ ) when the tip of the stud ST is in contact with the workpiece W. Each data is output in response to a request from the processing circuit 26. The contact detector 27 is a stud ST attached to the holder 9.
Of the auxiliary power source 28 detects a short-circuit current flowing from the auxiliary power source 28, resets the up-down counter 24, and sends a contact detection signal to the arithmetic processing circuit 26 to send a motor to the motor. Stop the rotation of 5. The arithmetic processing circuit 26 uses the setting signals δ ₁ , δ from the setter 21a.
₂ or δ ₃ is temporarily stored, and in response to signals from the switch 2 and the contact detector 27 for the start command, the electric motor 5
The sequence control for sequentially outputting the forward / reverse rotation command signals is performed. 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 pull-up amount δ ₁ and the push-in amount δ ₂ (or the pull-down amount δ ₃ ) are set according to the diameter, material, required welding quality and the like of the stud ST to be welded. Further, it is assumed that the holder 9 has been moved to an appropriate position in the Z ₁ direction in the figure in advance. When a start command is given by the operation switch 2 in this state, the arithmetic processing unit 26 outputs a normal rotation signal to the electric motor 5 by this, and the electric motor 5 is normally rotated by this signal, and the holder 9 is moved downward in the drawing.
That is, it is moved in the Z ₂ direction. When the tip of the stud ST comes into contact with the workpiece W due to the normal rotation of the electric motor 5, a short-circuit current flows from the auxiliary power source 28 to this contact portion, and the contact detector 2
7 detects this and sends the contact detection signal s to the arithmetic processing circuit 26.
Output ₁ As a result, the arithmetic processing circuit 26 reads the pull-up amount signal δ ₁ and outputs it to the comparator 22a 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 count 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 to move the holder 9 upward (Z ₁
Direction). The stud S is lifted 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 the output pulses of the detector 6.

On the other hand, at the same time when the contact detection signal s ₁ is generated,
Alternatively, at the same time when the holding tool 9 is pulled up, the arithmetic processing circuit 2
6 outputs an output start command signal s ₂ 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 both are short-circuited, and the holder 9 is pulled up by the reverse rotation of the electric motor 5, and the two are Generates an arc when leaving. When the electric motor 5 raises the holder 9 by the set pull-up amount δ ₁ , both inputs of the comparator 22a are balanced and stopped at that position. During this time, the arc continues for the duration of the energization timer set by the arithmetic processing circuit 26. When the energization timer ends, the signal s ₂ disappears and the welding power source E cuts off the output, so that the arc disappears. At the same time, the arithmetic processing circuit 26 reads out the data of the pushing amount δ ₂ and supplies the analog signal corresponding to the signal δ ₂ (the sign is opposite to the signal δ ₁ ) to the comparator 22a. Container 22a
Causes the input signals to become unbalanced, causing the electric motor 5 to rotate normally and the holder 9 to move downward. This amount of movement is detected by the detector 6, and the output signal thereof causes the up / down counter 24 to count down in the opposite manner, the count value is sequentially decreased from the previous δ ₁ , and passes through zero to −δ _2. Then, both input signals of the comparator 22a are balanced and stopped.
(End of pushing operation)

At this time, the stud ST first comes into contact with the workpiece W.
The position is pushed downward by δ ₂ (Z ₂ direction) than when the tip of the stud ST comes into contact with the tip, and this pushing amount δ ₂ becomes the penetration amount of the stud ST. After the pushing has been completed and the electric motor 5 has stopped, the electric motor 5 is held as it is for the set time of the holding timer. After that, the electric motor 5 is reversely rotated again to drive the holder 9 in the Z ₁ direction, and stopped at an appropriate position to move to the next position. Prepare for welding.
It should be noted that the counter 24 can be reset to zero the count content when the holder 9 is stopped at an appropriate position in the Z ₁ direction after mounting the stud ST. . in this case,
The detector 6 obtains the amount of movement δ ₀ until the stud ST moves in the Z ₂ direction from the start position to come into contact with the workpiece W, and the movement amount data δ ₀ and the set data δ ₁ ,
The stud ST is appropriately pulled up and pushed in by using δ ₂ .

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 values to the movement amount setter 21a can be selected appropriately, that is, the variable values can be set. Since it can be set purely electrically using resistors, pushbutton switches, rotary switches, etc., adjustment work can be performed quickly and extremely easily compared to the conventional mechanical adjustment work of components. In addition, since the conventional positioning mechanism by mechanical contact is not used, the structure of the arc stud welding gun can be simplified and can be manufactured at low cost. And deterioration of welding quality due to loosening of the positioning mechanism, etc.
For each stud welding, accurate welding according to the set value input to the movement amount setter 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, it is possible to efficiently perform arc stud welding by making the posture suitable for the operator. be able to.

Furthermore, even if there is an object to be welded W ₁ protruding in the Z ₁ direction near the welding position, the abutting member 11 is arranged so that the gun body 1 is located in the direction Z _{1 with} respect to the object to be welded W _1. The desired arc stud welding can be performed by adjusting.

Further, since the stud pull-up amount δ ₁ and push-in amount δ ₂ are set on the basis of the state in which the contact member 11 and the stud ST are in contact with the workpiece W, the stud length varies. Even if there is, the amount of stud pull-up δ ₁
And the indentation amount δ ₂ are not affected at all. Therefore, the desired quality of welding is achieved.

After the stud ST is pulled up, when the stud ST is moved in the Z ₂ direction, that is, the stud S
If the moving speed of the stud ST after the contact with the molten portion on the side of the object to be welded is high at the time of pushing in the T, the molten metal is scattered and a good welding result cannot be obtained. Therefore, at the time of pushing, it is necessary to control so that the speed after the stud is pushed into the vicinity of the contact position between the work piece before pulling up and the stud is smaller than the initial velocity of the stud. For example, the tact time at the time of pushing can be shortened, and high quality welding can be performed without scattering molten metal.

In FIG. 5, the pulling amount δ ₁ and the pushing amount δ ₂ are preset and the moving speed of the stud ST is set to different speeds in each stroke so that the position and the speed are automatically set to the set values. FIG. 3 is a connection diagram showing an example of a device that allows the electric motor 5 to operate. In the figure, the control circuit 20 uses the control circuit shown in FIG. 3 to convert the output pulses of the moving speed setter 21b and the detector 6 into a voltage according to the pulse frequency to obtain 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 both outputs of the comparator 22a and the comparator 22b are added to drive electrically. The 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 in the examples shown in FIGS.

In the apparatus of FIG. 5, the movement amount setting device 21a
Is the amount of pull-up δ ₁ , the amount of push-in δ ₂ or the amount of pull-down δ ₃ (= δ ₁ + δ ₂ ) when the tip of the stud ST is in contact with the workpiece W, and the speed at the time of push-in. The moving amount δ ₂₁ (δ ₂₁ <δ ₃ ) until the change is preset, and the speed setter 21b moves the moving speeds s ₁₁ and s ₁₂ during pulling up, and the moving speeds s ₂₁ and s ₂₂ during pulling down and pushing. , S ₂₃ (s ₂₂ > s ₂₃ )
Is preset and each data is output in response to a request from the arithmetic processing circuit 26. The contact detector 27 detects when a 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 source 28, and resets the counter 24. , 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 and the moving speed setting signals s ₁₁ , s ₁₂ , s ₂₁ , s ₂₂ , s ₂₃ from the setters 21a and 21b, and also starts. According to signals from the command switch 2 and the contact detector 27, sequence control for sequentially outputting forward and reverse command signals to the electric motor 5 is performed. For example, similar to the embodiment of FIG. −
The 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 work, the amount of pull-up δ ₁ and the amount of push-in δ ₂ (or the amount of pull-down δ ₃ ), the amount of movement until the speed is changed during pushing (the amount of movement in the first half of the pushing stroke) δ ₂₁ , the stud ST being welded Moving speed (first descending speed) s ₂₁ when pulling down to contact the object W, first lifting speed s ₁₁ when pulling up from the contact state, and moving amount is δ ₂₁ from the beginning of the pushing stroke. The speed in the first half (second lowering speed) s ₂₂ , which corresponds to the speed of reaching, the speed (third lowering speed) s _{23 in} the latter half of the pushing stroke, and the speed at which the holding tool 9 is pulled up to the retracted position after welding ( The second rising speed) s ₁₂ is set according to the diameter, material, required welding quality and the like of the stud ST to be welded. In addition, the holder 9 is previously Z _{1 in the} figure.
It has been moved to an appropriate position in the direction.

When a start command is given by the operation switch 2 in this state, the arithmetic processing unit 26 outputs a normal rotation signal of the speed s _{21 to} the electric motor 5, which causes the electric motor 5 to be positive at the set speed s ₂₁ . The holder 9 is rotated to move it downward in the figure, that is, in the Z ₂ direction. When the tip of the stud ST comes into contact with the workpiece W due to the normal rotation of the electric motor 5, a short-circuit current flows from the auxiliary power source 28 to this contact portion, and the contact detector 27 detects this and the arithmetic processing circuit 26 detects contact. The signal s ₁ is output. As a result, the arithmetic processing circuit 26 reads out the pull-up amount signal δ ₁ and the first pulling speed signal s ₁₁ and, via the D / A converters 23a and 23b, the comparator 22a,
22b.

On the other hand, the contact detection signal s ₁ is also supplied to the counter 24 to reset the count 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. Therefore, the output of the comparator 22a becomes −δ _{1 and} the output of the comparator 22b becomes −s ₁₁ , which causes the electric motor 5 to rotate in the reverse direction and the holder 9 to move upward at the set speed s _{11 in the} figure. Z ₁ direction)
Move to. When the short-circuit between the stud ST and the workpiece W is eliminated by the rise of the holder 9, the contact detection signal s ₁ disappears, the counter 24 is released from the reset state, and the counting of the output pulse of the detector 6 is started. ..

On the other hand, simultaneously with the generation of the contact detection signal s ₁ ,
Alternatively, at the same time when the holding tool 9 is pulled up, the arithmetic processing circuit 2
6 outputs an output start command signal s ₂ 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 both are short-circuited, and the holder 9 is pulled up by the reverse rotation of the electric motor 5, and the two are Generates an arc when leaving. When the electric motor 5 raises the holder 9 by the set pull-up amount δ ₁ , both inputs of the comparator 22a are balanced and stopped at that position. During this time, the arc continues for the duration of the energization timer set by the arithmetic processing circuit 26. When the energization timer ends, the signal s ₂ disappears and the welding power source E cuts off the output, so that the arc disappears. At the same time, the arithmetic processing circuit 26 reads the data of the pushing amount δ ₂ , the movement amount δ ₂₁ until the speed change, the first half speed s ₂₂ and the second half speed s ₂₃ , and outputs the respective signals to the comparators 22a and 22b. Corresponding to the comparators 22a, 2
In 2b, the input signals become unbalanced, the electric motor 5 is rotated in the normal direction, and the holder 9 is moved downward at the set speed. This movement amount is detected by the detector 6, and the output signal thereof causes the counter 24 to down-count, contrary to the above, and when the count value decreases from the previous δ ₁ and the movement amount reaches δ ₂₁ , Compared when the speed setting signal is changed to the third lowering speed s ₂₃ , the lowering continues further at a speed slower than the first half of the pushing stroke, and the count value of the counter 24 passes zero and becomes −δ _2. Both input signals of the device 22a are balanced and stopped. (End of pushing operation)

At this time, the stud ST first comes into contact with the workpiece W.
Than when the tip touches ₂Just below (Z₂Person
Direction) and the pushing amount δ₂Is stupid
It becomes the penetration amount of ST. When pushing is completed, the electric motor 5
After stopping, it is held as it is for the set time of the hold timer.
And then the electric motor 5 is again moved to the speed s₁₂Reversing with and holding
9 for Z₁Drive in the direction, stop when the upper limit is reached, and then
Prepare for welding. Note that the studs are the same as in the embodiment of FIG.
After mounting ST, the holder 9 becomes Z₁Stop at the appropriate position in the direction
The counter 24 is reset while counting
Can be zero. . In this case, the stud ST
Z from the start position₂Moves in the direction and contacts the workpiece W
Amount of movement until₀This is obtained by the detector 6
Quantity data δ₀And the set data δ₁, Δ₂, Δ_{twenty one}And
The stud ST can be pulled up and pushed in as appropriate.
Be done.

Of course, when it is necessary to change the set values of the stud pull-up amount δ ₁ , push-in amount δ ₂ and δ ₂₁ as in the embodiment shown in FIG. 3, the input set value to the setter 21 is changed. It may be appropriately selected by a variable resistor, a push button switch or a rotary switch. Further, 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 the means for detecting the movement speed, but instead of these, a rotary shaft of the driving machine 5 is used. The tachogenerator may be coupled so that a voltage proportional to the speed of movement is directly obtained. In this case, since the speed detection signal is obtained as an analog signal, the F / V converter used in the speed detection circuit in the device of FIG. 5 becomes unnecessary, and the output of the tachogenerator is used as it is, or a comparator is provided via an appropriate amplifier or attenuator. 22b.

Here, the set values of the moving speed s ₁₁ , s ₁₂ , s
₂₁ to s ₂₃ will be described. The first descending speed set value s ₂₁ determines the moving speed until the tip of the stud ST first set on the holder 9 is lowered and the tip of the stud ST comes into contact with the object W to be welded. It is necessary to set it relatively late in order to reduce. At this time, it is also necessary to reduce the force generated by the driving machine to prevent damage at the time of contact. For this purpose, if the driving machine is composed of an electric motor, the supply current may be limited so as to limit the torque (or thrust) generated by the driving machine.

Further, 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 rising is sufficiently grown by the short-circuit current supplied from the welding power source E at the time of contact and no arc breakage occurs. The pulling speed after completion of pulling may be high until the tip of the stud ST comes into contact with the molten metal pool of the workpiece to be welded by the arc, and then relatively slow down to the molten pool and the stud tip. The generated molten metal portion is prevented from scattering due to impact. For this reason, the speed of the first half stroke (from the previous pulling position to the place where it has descended by δ ₂₁ ) during pushing is determined.
The descending speed set value s _{22 of} is set to be high, and the third descending speed set value s ₂₃ that determines the speed of the second half stroke is set to be slow. Further, since the welding quality is not affected at all when pulling after the completion of welding, the tact time can be reduced by setting the second rising speed s ₁₂ to a high speed within a range that does not affect the durability of the drive system. To illustrate the relationship between the set speeds, s ₁₁
<S ₁₂ , s ₂₂ > s ₂₃ >> s ₂₁ . Also the rising speed s ₁₁
And s ₁₂ may have substantially the same value, and since the signs of s ₂₂ and s ₁₁ are opposite and welding can be performed substantially even if they have the same value, in this case, there are three types of set values: signal s ₁₁ , s ₂₁ , s ₂₃ . Will be good. (S ₁₁ = s ₁₂ = -s ₂₂ )

Further, the speed setting at the time of pushing may be a signal that changes in a polygonal line of several steps in addition to the two steps such as the signals s ₂₂ and s ₂₃ as described above, or from the start of pushing to the completion of pushing. The setting signal may be set so as to continuously change from high speed to substantially zero during the interval. In these cases, the speed setting signal s _2n is the amount of movement δ of the holder 9 during pushing.
Corresponding to _2n , it may be determined as a function of movement amount s _2n = f (δ _2n ). Further, as these speed setting signals, several kinds of preprogrammed signals having different changes may be prepared and selected according to the material and diameter of the stud to be welded, the required welding quality and the like.

In FIGS. 3 and 5, the stud ST is moved after the stud is mounted to electrically detect the contact state between the tip of the stud ST and the workpiece W. Therefore, the stud is mounted. Regardless of the position of the holding tool 9 in front and the setting position of the abutting member 11 with respect to the gun body 1, desired setting of pulling up and down of the stud ST after contact between the tip of the stud ST and the workpiece W is performed. It can be carried out automatically so as to be in a state.

Further, the tip of the stud ST and the object to be welded W
The contact with can be performed manually as described below. That is, the gun body 1 equipped with the stud ST is
When arranged as shown in FIG. 1 through the abutting member 11 that contacts the workpiece W, the tip of the stud ST is Z ₁
When the rotary member 3 is positioned on the directional side, the rotating member 3 can be freely rotated by freeing the electric motor 5 itself against rotation, or by appropriately providing a clutch in the drive system.
An operator can manually move the holder 9 and the stud ST in the Z ₂ direction to bring the tip ends of the stud ST and the contact member 11 into contact with the workpiece W.

On the other hand, when the stud ST is mounted and the tip of the stud ST is located closer to the Z ₂ direction side than the tip of the abutting member 11, the rotary member 3 is rotatable as described above. The operator is the holder 101 of the gun body 1.
While holding the tip of the stud ST against the workpiece W while pressing 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 tip portions of the stud ST and the contact member 11 are brought into contact with the workpiece W by human power, the contents of the output counter 24 of the detector 6 are set to zero in this contact state. When reset, the stud ST can be pulled up and down based on the preset values preset in the setters 21a and 21b.

In the embodiment shown in FIG. 3 and FIG. 5, both outputs of the setters 21a and 21b and the output of the detector 6 of the electric motor 5 are comparatively controlled by the control circuit 20, that is, a so-called ?? -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 arc stud welding is performed by the control of a so-called open loop system based on each set value of the setters 21a and 21b electrically connected to the electric motor 5. You can also do it.

Next, a case where a so-called ferrule F that covers the tip of the stud ST is used will be described. 7 to 10, which is the second embodiment, 11, 11
Is an abutting member that is bridged through the bridging member 111 at the end in the Z ₂ direction and abuts against the workpiece W at one or more positions. Member 1 that abuts at a point
13, 114 are provided. The bridging member 111
Is provided with a notch portion 112 for pressing the shoulder portion of the ferrule. In addition, the ends of the contact members 11, 11 in the Z ₁ direction are supported by the gun body 1. Preferably,
The end positions of the contact members 11, 11 in the Z ₁ direction are the gun body 1
It is supported so that its position can be freely set in the Z direction. Reference numeral 12 is a rotary shaft rotatably supported by the gun body 1 via bearings 13, 13 and is provided with a male screw 121a, optimally a ball screw. An end of the rotary shaft 12 in the Z ₁ direction is appropriately connected to the rotating electric motor 5 via a speed reducer. A detector 6 that detects the drive amount of the electric motor 5 is connected to the electric motor 5. 14 is a contact member 1
A frame body that is movable in the Z direction while being positioned by 1, 1 and 11, is a female screw 141 that is screwed into a male screw 121a of the rotary shaft 12, optimally a ball nut, and the contact members 11, 11.
Guide portions 142, 142 that slide along are provided. A holder 9 for holding the stud ST is arranged on the frame body 14.

In the second embodiment, the contact member 11
7 and FIG.
Further, as shown in FIG. 10, the ferrule F is pressed near the notch 112 of the contact member 11. A control circuit 2 similar to that shown in FIG. 3 or 5 is provided with a setting device for presetting the pull-up amount, the pull-down amount or the moving speed of the stud ST.
The configuration of 0 is the same as in the first embodiment. The arc stud welding work is exactly the same as that of the first embodiment except for the above-mentioned matters relating to the ferrule, and therefore the explanation of the operation and the modification will be omitted. In addition,
In the first and second embodiments, the stud welding start signal is provided with a dedicated operation switch on the gun body 1 or the foot-operated operation box, or the gun body 11 is provided with a changeover switch in addition to the operation switch 2. By installing the switch, using the operation of the operation switch 2 and a timer together, or providing multiple switches on the foot-operated or manual operation type operation box without providing the operation switches on the gun body 1, Can be carried out. Of course, in the second embodiment, the notch 112 may be provided at the tip of the contact member 11 or 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 full-automatic arc stud welding. That is, in the fully automatic stud welding apparatus, the position of the tip support member that supports the stud welding gun is moved in the Z direction at the time of stud welding by using, for example, the Z-direction drive mechanism provided as the welding apparatus. If you try to do so, the vibration of the welding equipment that accompanies the drive of the large drive mechanism is transmitted to the stud welding gun, and the backlash or response delay of the large drive mechanism causes the stud to rise. The amount and the pushing amount cannot be set to desired states.

Therefore, even in a fully automatic arc stud welding apparatus, a gun main body positioned with respect to an object to be welded and a holder provided on the gun main 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 a position, wherein an electric driving machine for moving the holder in the longitudinal direction of the stud, and an electric driving machine electrically connected to the driving machine, An arc stud welder provided with a control circuit capable of presetting the amount of displacement and speed is used.

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

In this way, as the stud welding gun 30,
Explaining the case where no member that abuts on the workpiece W is provided, in FIG. 11, when the drive mechanism 41 of the welding device 40 positions the tip support member 411 at the welding position, the tip of the stud ST and A preset value corresponding to the stud pull-up amount δ ₁ and the pull-down amounts δ ₂ , δ ₂₁ , and δ ₃ driven by the holder 9 in the stud welding gun 30 is set on the basis of the state of contact with the welded object W. be able to. In this case, a minute voltage is applied between the stud ST and the object W to be welded, and the tip support member 411 and the stud welding gun 30 are moved to Z ₂ by driving the drive mechanism 41.
Drive in the direction, and the drive mechanism 41 is stopped when the stud ST and the workpiece W are electrically short-circuited.

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

In each of the above-described embodiments, an example in which both the pull-up amount and the push-in amount of the stud are preset to control the entire stroke of the movement of the stud has been described, but the present invention is limited to the pull-up amount only. It is also applicable to the case of presetting and performing without pressing the position control. In this case, at the time of pushing, by pushing with a predetermined pushing force, the stud stops at a position where the reaction force from the welded portion and the pushing force are balanced. In this case, the amount of pull-up that most affects welding is accurately controlled, so that the amount of heat supplied to the weld is accurately controlled and the amount of melting of the stud and the work piece is accurate. Therefore, when the stud is pushed into the fusion zone 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 during the pushing stroke so that the stud is substantially in contact with the workpiece and the stud before pulling up with respect to 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 can be shortened and high-quality welding can be performed in which molten metal is not scattered.

Further, in the present invention, since the holder driving mechanism is driven and controlled by the electric driving machine, fine position control and variable control of driving force can be carried out inexpensively and easily. Of course, in arc stud welding,
Since the pulling amount and pushing amount of the stud are variously changed, and moreover, it is necessary to finely adjust the pulling amount and pushing amount. Therefore, in a so-called pressure fluid type drive machine such as hydraulic pressure or compressed air However, it is not practical to make it possible to finely adjust in correspondence with variously changed pull-up amount and push-in amount, since not only the structure becomes extremely complicated but also the price rises.

In addition to the moving amount and moving speed, the driving force immediately before the completion of pushing into the melted portion can be controlled to be smaller or larger than the driving force in other portions. With this control, it is possible to freely select an already welded portion.

Further, as the movement amount detector of the holder moved by the driving machine, an appropriate detector such as a rotary encoder, a potentiometer or a differential transformer can be freely selected. Furthermore, a rotary electric motor or a direct drive electric motor, for example, a linear motor can be adopted as an electric drive machine for moving the holder.

[0067]

As is apparent from the above description, the arc stud welding machine according to the first and second aspects of the present invention is
An electric drive machine that moves the stud holder in the long axis direction of the stud, a movement amount setter that is electrically connected to the drive machine, and that can preset at least the stud lift amount, and this movement amount setting Since a drive machine control circuit for displacing the holder according to the set value of the tool is provided, the conventional mechanical positioning mechanism is not required, and the structure of the arc stud welding machine is simple and inexpensive. In addition to being able to be manufactured, the desired arc stud welding can be performed by pure electrical control for each stud welding without causing deterioration of welding quality due to wear of the abutting member or loosening of the positioning mechanism as in the conventional case. It can be performed reliably, and at least the amount of stud lifting before welding can be adjusted by selecting the input set value to the setter. 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, it is possible to efficiently perform arc stud welding by making the posture suitable for the operator. be able to. Of course, even if there is a workpiece W ₁ protruding in the Z ₁ direction near the welding position, the contact member 11 should be adjusted so that the gun body 1 is located in the Z ₁ direction relative to the workpiece W _1. As a result, desired arc stud welding can be performed.

Further, the arc stud welding machine according to the third and fourth aspects of the present invention is an electric drive machine for moving the stud holder in the longitudinal direction of the stud, and a holder moved by the drive machine. A movement amount detector for detecting the movement amount of
When the retainer reaches the set value of the travel amount setting device by inputting at least the travel amount setting device that can preset the stud pull-up amount and the set value of this travel amount setting device and the detection value of the travel amount detector. 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, the arc stud of a high-performance set value is achieved by the electric control of the feedback system. Welding can be performed.

Further, in the arc stud welding machine according to the fifth and sixth aspects of the invention, an electric drive machine for moving the stud holder in the longitudinal direction of the stud, and a holder moved by the drive machine. A movement amount detector for detecting the movement amount of
At least the movement amount setter capable of presetting the pull-up amount of the stud, and the holding device when the holding device reaches the setting value of the setting device by inputting the setting value of the setting device and the detection value of the detector When the tool movement is stopped and the stud is pushed in, the speed after the stud is pushed into the vicinity of the contact point between the stud and the workpiece to be welded before pulling up is smaller than the initial speed of the stud. Since the servo control circuit is controlled so that the desired arc stud welding can be performed regardless of variations in the stud length, in addition to the effects of the third and fourth inventions, The tact time at the time of pushing can be shortened, and high quality welding can be performed without scattering molten metal.

[Brief description of 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 showing an example of a control circuit used in FIG.

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

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

6 is a flow chart for explaining the operation of the control circuit of FIG.

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

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

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

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

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 a state explanatory view of general arc stud welding.

[Explanation of symbols]

 1 gun body 2 operation switch 5 electric drive 6 detector 9 stud holder 11 contact member 20 control circuit 21a movement amount setter 21b speed setter 22a, 22b comparator 23a, 23b, 23c D / A conversion Unit 26 Arithmetic processing circuit 27 Contact detector 28 Auxiliary power source 29 F / V converter 30 Stud welding gun E Welding power source ST Stud F Ferrule

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] May 14, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 8

[Correction method] Change

[Correction content]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0020

[Correction method] Change

[Correction content]

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

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction content]

The ninth invention is characterized in that, in the fifth to eighth inventions, the speed setting signal is determined in relation to the moving amount.

[Procedure amendment 4]

[Document name to be amended] Statement

[Correction target item name] 0024

[Correction method] Change

[Correction content]

Reference numeral 7 denotes a male screw 701 which is screwed into the female screw 301 of the rotary member 3, and optimally a holding shaft provided with a ball screw. At least one shaft is provided outside the holding shaft 7. Directional grooves 702 are provided. Reference numeral 8 is a locking member supported by the gun body 1, for example, a sliding key.
The holding shaft 7 is movably supported by the gun body 1 only in the axial direction, that is, in the Z direction. A holding tool 9 holds the stud ST, and is supported by the holding shaft 7 via an appropriate electrical insulating member. Reference numeral 11 is an abutting member for abutting against the object W to be welded to position the gun body 1. In the case shown in the drawing, the abutting member 11 is the gun body 1
It is supported by the gun body 1 so that the position in the major axis direction of the, i.e., the Z direction can be set freely. Reference numeral 20 is a control circuit of the driving machine 5 for displacing the holder 9, and reference numeral 21a is a movement amount setter for setting 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 uses the movement amount setting device 21a.
The set value of 1 and the output of the movement amount detector 6 are input, and the holder 9 is positioned at a position where both inputs match. The semi-automatic arc stud welding gun 30 is configured by the above 1 to 11, and the servo control circuit that controls the movement amount of the holder 9 is configured by the movement amount setting device 21a, the movement amount detector 6, and the driving machine control circuit 20. This welding gun 30, a servo control circuit, and a welding power source (not shown) constitute a stud welding machine.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction content]

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

[Procedure correction 6]

[Document name to be amended] Statement

[Name of item to be corrected] 0029

[Correction method] Change

[Correction content]

After the above, immediately before the pulling up amount of the stud ST becomes δ ₁ , or after that, after an appropriate consideration of the molten state of the stud ST and the workpiece W, for example,
The supply of the welding current is cut off after the weld plunges into the molten portion of the workpiece . After that, the electric motor 5 is driven in the forward direction so that the stud ST and the holder 9 move in the Z ₂ direction, and the stud ST is moved in the Z ₂ direction by the set amount δ ₃ by the detector 6 and the control circuit. , Arc stud welding is completed. Of course, in this case, the pushing amount of the stud ST into the workpiece W is δ ₂ (= δ ₃ −δ ₁ ). After welding
The holder 9 is appropriately moved in the Z ₁ direction automatically or by the operation of the operation switch 2 to complete the welding work for one cycle. The holder 9 can be moved in the Z ₁ direction after welding, and can be performed before or after the next stud is attached.

[Procedure Amendment 7]

[Document name to be amended] Statement

[Correction target item name] 0031

[Correction method] Change

[Correction content]

In the apparatus of FIG. 3, the movement amount setting device 21a
Is calculated by presetting the pull-up amount δ ₁ , the push-in amount δ ₂ or the pull-down amount δ ₃ (= δ ₁ + δ ₂ ) when the tip of the stud ST is in contact with the workpiece W. Each data is output in response to a request from the processing circuit 26. The contact detector 27 is a stud ST attached to the holder 9.
Of the auxiliary power source 28 detects a short-circuit current flowing from the auxiliary power source 28, resets the up-down counter 24, and sends a contact detection signal to the arithmetic processing circuit 26 to send a motor to the motor. Stop the rotation of 5. The arithmetic processing circuit 26 uses the setting signals δ ₁ , δ from the setter 21a.
₂ or δ ₃ is temporarily stored , and in response to signals from the switch 2 and the contact detector 27 for the start command, the electric motor 5
The sequence control for sequentially outputting the forward / reverse rotation command signals is performed. For example, a circuit using a microcomputer is used.

[Procedure Amendment 8]

[Document name to be amended] Statement

[Correction target item name] 0061

[Correction method] Change

[Correction content]

In this way, as the stud welding gun 30,
Explaining the case where no member that abuts on the workpiece W is provided, in FIG. 11, when the drive mechanism 41 of the welding device 40 positions the tip support member 411 at the welding position, the tip of the stud ST and A preset value corresponding to the stud pull-up amount δ ₁ and the pull-down amounts δ ₂ , δ ₂₁ , and δ ₃ driven by the holder 9 in the stud welding gun 30 is set on the basis of the state of contact with the welded object W. be able to. In this case, a voltage is applied between the stud ST and the object W to be welded, and the driving mechanism 41 drives the tip support member 411 and the stud welding gun 30 in the Z ₂ direction to weld the stud ST and the object to be welded. The drive mechanism 41 is stopped when the object W is electrically short-circuited.

[Procedure Amendment 9]

[Document name to be amended] Statement

[Name of item to be corrected] 0066

[Correction method] Change

[Correction content]

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

Claims (10)

[Claims] 1. A gun main body which is positioned with respect to an object to be welded, and a holder which is arranged on the gun main body and holds a stud, and an arc is generated at a contact position between the object to be welded and the stud. In an arc stud welding machine having a holder driving mechanism for displacing at least the pulled state for pushing and the pushed state after melting, in an arc stud welding machine, an electric drive machine for moving the holder in the long axis direction of the stud, A movement amount setting device that is electrically connected to the driving device and is capable of presetting at least the pull-up amount of the stud, and a driving device control circuit that displaces the holder according to a set value of the movement amount setting device. An arc stud welding machine characterized by having and. 2. A gun main body and a holder arranged on the gun main body, for holding a stud, in a pulled-up state for generating an arc with respect to a contact position between an object to be welded and the stud and after melting. The holder drive mechanism for displacing at least the position of the gun body and the contact member for contacting the object to be welded to position the gun body, while the operator grips the holder of the gun body. In an arc stud welding machine for welding, an electric drive machine that moves the holder in the longitudinal direction of the stud and a movement that is electrically connected to the drive machine so that at least the pull-up amount of the stud can be preset. An arc stud welding machine, comprising: an amount setting device; and a drive device control circuit for displacing the holder according to a set value of the movement amount setting device. 3. A gun main body positioned with respect to an object to be welded, and a holder arranged on the gun main body for holding a stud, and an arc is generated at a contact position between the object to be welded and the stud. In an arc stud welding machine having a holder driving mechanism for displacing at least the pulled state for pushing and the pushed state after melting, in an arc stud welding machine, an electric drive machine for moving the holder in the long axis direction of the stud, A movement amount detector for detecting the movement amount of the holder moved by the drive machine, a movement amount setting device capable of presetting at least the lifting amount of the stud, a set value of the movement amount setting device and the movement amount. An arc stud characterized by being provided with a servo control circuit which receives the detection value of the detector as input and stops the movement of the holder when the holder reaches the set value of the movement amount setter. welding Machine. 4. A gun main body and a holding member arranged on the gun main body for holding a stud, in a pulled state for generating an arc with respect to a contact position between a workpiece and the stud, and after melting. The holder drive mechanism for displacing at least the position of the gun body and the contact member for contacting the object to be welded to position the gun body, while the operator grips the holder of the gun body. In an arc stud welding machine for welding, an electric drive machine that moves the holder in the longitudinal direction of the stud, a movement amount detector that detects a movement amount of the holder moved by the drive machine, and at least the above The amount of movement of the stud can be preset, and the set value of the moving amount setter and the detected value of the moving amount detector are input, and the holder reaches the set value of the moving amount setter. Sometimes the holder And a servo control circuit for stopping the movement of the arc stud welding machine. 5. A gun main body which is positioned with respect to an object to be welded, and a holder which is arranged on the gun main body and holds a stud, and an arc is generated at a contact position between the object to be welded and the stud. In an arc stud welding machine having a holder driving mechanism for displacing at least the pulled state for pushing and the pushed state after melting, in an arc stud welding machine, an electric drive machine for moving the holder in the long axis direction of the stud, A movement amount detector that detects the movement amount of the holder moved by the drive machine, a movement amount setting device that can preset at least the lifting amount of the stud, and at least a movement speed when the stud is pushed can be preset. A speed setting device, and at least the set value of the moving amount setting device, the detection value of the moving amount detector and the setting value of the speed setting device are input, and the holding device moves when the holding device moves. An arc stud welder equipped with a servo control circuit for controlling a moving amount and a moving speed so as to match a set value. 6. A gun main body and a holding member which is disposed on the gun main body and holds a stud, is in a pulling state for generating an arc with respect to a contact position between the object to be welded and the stud, and after melting. The holder drive mechanism for displacing at least the position of the gun body and the contact member for contacting the object to be welded to position the gun body, while the operator grips the holder of the gun body. In an arc stud welding machine for welding, an electric drive machine that moves the holder in the longitudinal direction of the stud, a movement amount detector that detects a movement amount of the holder moved by the drive machine, and at least the above A movement amount setting device capable of presetting the amount of pulling up of a stud, a speed setting device capable of presetting a movement speed at least when the stud is pushed in, at least a set value of the movement amount setting device, and the movement amount detector. And a set value of the speed setter are inputted, and an arc stud welder equipped with a servo control circuit for controlling the moving amount and moving speed of the holding tool so as to match the set value when the holding tool is moved. .. 7. The speed setting device is a setting device which outputs a two-step set value that slows down the speed of at least the first half portion of the pushing stroke of the stud, rather than the first half portion. Arc stud welder described in. 8. The speed setting device is a setting device that outputs a signal that the speed continuously decreases at least in the latter half of the pushing stroke of the stud.
The arc stud welding machine according to any one of 1. 9. The speed setter is a setter that outputs a signal that changes in accordance with the displacement amount of the holder, and the servo control circuit sets the set value of the movement amount setter and the speed setter. 9. The arc stud welding machine according to claim 5, wherein the arc stud welding machine is a servo control circuit for controlling a moving amount and a speed by inputting a set value of the above and a detected value of the moving amount detector. 10. The movement amount setting device is capable of presetting both a pull-up amount and a push-in amount of a stud.
An arc stud welder according to claim 9.