JP2762236B2 - Auxiliary gun device for spot welding - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spot welding auxiliary gun device for performing spot welding in cooperation with a welding gun of a spot welding welding robot.

[0002]

2. Description of the Related Art Conventionally, in a car manufacturing plant and various other manufacturing plants, etc., a work is conveyed by a pallet.
In many cases, spot welding is performed on each part of a workpiece by a spot welding gun mounted on a hand part of a welding robot.
When there is a part that cannot be welded due to restrictions such as the posture and space of the hand of the welding robot, welding is performed by the welding robot of the next station or welding is performed by changing the welding gun of the hand, which is not rare. .

On the other hand, in order to weld a portion that cannot be welded by a welding robot, a dedicated automated spot welding device may be provided on a pallet or a pallet conveyance path.
This spot welding apparatus is provided with at least a pair of spot welding electrodes so as to face each other at the distal ends of a pair of gun arms, and is configured to be able to conduct electricity to these spot welding electrodes from a welding power supply device. An air cylinder for driving the pair of gun arms to the welding position is provided, and at the time of welding, spot welding is performed by driving the pair of gun arms to the welding position and energizing the spot welding electrodes by the air cylinder.

[0004]

The dedicated spot welding apparatus is the same as the spot welding gun of the welding robot.
Since it is provided independently and configured to supply power from its own welding power supply device, and because it is configured to be controlled by another control device without controlling by the control unit of the welding robot, the equipment It is very disadvantageous in terms of cost and installation space. An object of the present invention is to provide a spot welding auxiliary gun apparatus such as wear and conduction function and a pressing function of the gun for spot welding of welding robots for spot welding in effective use.

[0005]

An auxiliary gun device for spot welding according to claim 1 is an auxiliary gun device for spot welding for performing spot welding in cooperation with a welding gun of a welding robot for spot welding. And the body frame,
1 each having a spot welding electrode at the opposite end
A pair of gun arms, a welding position at which both spot welding electrodes approach each other across the work,
A pressurizing force is applied to the pair of gun arms from a welding gun of a welding robot to the main body frame so as to be openable and closable over a non-welding position where both spot welding electrodes are separated from each other. and in order to be energized, a pair of gun arm
The pair of pressurizing and energizing sections formed at a position distant from the spot welding electrode and the pair of gun arms are fused.
Drive that includes an air cylinder that presses and drives to the welding position when in contact
Means.

[0006] Also, the pair of gun arm, may be a spring member elastically biased in the non-welding position is provided (according
Item 2 ). Further, the pair of gun arms may be formed in a straight shape in a side view ( claim 3).

[0007]

In the auxiliary gun device for spot welding according to the first aspect, the pair of gun arms have spot welding electrodes at opposite end portions, respectively, and the pair of gun arms are pivotally supported. By the mechanism, the two spot welding electrodes are pivotally supported on the main body frame so as to be openable and closable over a welding position at which the two electrodes come close to each other across a workpiece and a non-welding position at which the two spot welding electrodes are separated from each other. In order to apply a pressing force from the welding gun of the welding robot to the pair of gun arms and to energize the pair of gun arms, a pair of pressurizing and energizing sections is provided at a position distant from the spot welding electrode. Is formed.

Accordingly, in a state where the pair of gun arms are opened to the non-welding position and the work is set between the spot welding electrodes of the pair of gun arms, the welding robot is moved to the pair of pressurizing and energizing sections. When a pressing force is applied from the welding gun and the current is applied, the pair of gun arms closes to the welding position and is energized, so that spot welding can be performed by the spot welding electrodes of the pair of gun arms. Only
Also, press the pair of gun arms to the welding position during welding.
Drive means including an air cylinder
At this time, the pressing force of this driving means and the welding gas of the welding robot
The required pressing force is generated with the pressing force of
Can be secured.

As described above, since the pressurizing function and the energizing function of the welding gun of the welding robot can be effectively utilized, it is very advantageous in terms of equipment cost and installation space. In addition, since a portion remote from the pair of pressurizing and energizing portions that can be reached by the welding gun of the welding robot can be welded, the use efficiency of the welding robot can be improved. Furthermore, the main body frame,
Since it has a simple structure consisting mainly of a pair of gun arms, a pair of spot welding electrodes, a pivot mechanism, and a pair of pressurizing and energizing parts, it is compact, lightweight, easy to handle, and inexpensive. it can.

[0010] In the auxiliary gun device for spot welding of 請 Motomeko 2 due to the provision of the spring member for elastically urging the pair of gun arm in the non-welding position, after welding, by the spring member, the pair of gun arms non It can be automatically switched to the welding position. In the auxiliary gun device for spot welding according to the third aspect, the pair of gun arms are formed in a straight shape in a side view, but in this case, the structure of the pair of gun arms is simplified .

[0011]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, the spot welding auxiliary gun device 1 is fixed to a pallet 9 for setting and transporting a workpiece W in advance, and is mounted in an upright state in this embodiment. In order to weld a portion which cannot be directly welded by the spot welding machine 5, a predetermined welding point of the work W is set in advance in a state where it can be welded by the auxiliary gun device 1 for spot welding, and the pallet 9 on which the work W is set is transferred to the pallet. While being conveyed along the line, at a predetermined station, spot welding is performed in cooperation with the spot welding auxiliary gun device 1 and the spot welding machine 5.

A spot welding machine 5 is mounted on a hand unit 4 of an articulated robot 2 which is a robot body of the welding robot. The spot welding machine 5 comprises a spot welding gun 6, an air cylinder 8, and the like. A pair of electrodes 7 are exchangeably mounted on the output tip of the welding gun 6 so as to face each other. The spot welding gun 6 is driven to open and close by an air cylinder 8, and is driven by a pair of electrodes 7 to pressurize and energize the pressurizing and energizing section 19 of the spot welding auxiliary gun device 1. Apparatus 1
Thus, spot welding is performed on the work W. The spot welding gun 6 and the air cylinder 8 of the spot welding machine 5 are connected to the control unit 3 via a power supply cable, a control signal line, a pressurized air supply hose, and the like. The drive is controlled by the unit 3.

As shown in FIGS. 2 to 4, the auxiliary gun device 1 for spot welding is composed of a main body frame 10 and a pair of gun arms 15 each having an electrode 17 for spot welding at opposing distal ends. A pair of gun arms 15 having a pair of pressurizing and energizing portions 19 for applying a pressing force and energizing from the spot welding gun 6 of the spot welding machine 5;
A pair of gun arms 15 is connected to a pair of electrodes 17 for spot welding.
A pivot mechanism 30 that pivotally supports the main body frame 10 so as to be freely opened and closed over a position where the pair of electrodes 17 approach each other across the work W and a non-welding position where the pair of spot welding electrodes 17 are separated from each other;
The pair of gun arms 15 are configured by an opening / closing drive mechanism 41 that drives the pair of gun arms 15 to open and close over a welding position and a non-welding position.

First, the main body frame 10 will be described (see FIGS. 2 to 6). The main body frame 10 includes a plate-shaped base plate 11 having a rectangular shape in a plan view, a U-shaped pivot bracket 12 in a front view, and a plate-shaped support member 13 for fixing the pivot bracket 12 to the base plate 11. ing. The pivot bracket 12 has its upper wall portion 12u and lower wall portion 12w parallel to the base plate 11, and is fixedly supported on the base plate 11 via a support member 13. Upper wall 12u and lower wall 1
2w, a pair of pivot holes 12a penetrate in a plane orthogonal to each other and are formed in opposing shapes.
Is concentric with the pivot hole 12a and has a large diameter.
A pivot shaft 31 described later is rotatably mounted in these pivot holes 12a.

Next, the pair of gun arms 15 will be described (see FIGS. 2 and 3). The pair of gun arms 15 are made of a copper alloy having excellent electrical conductivity, are arranged in parallel with and opposite to the base plate 11, and the pair of gun arms 15 are formed symmetrically to the left and right. Left gun arm 15
More specifically, the gun arm 15 includes an output tip 16 having a spot welding electrode 17 and a pressurizing and energizing unit 1.
A wide portion 18 having a base 9 and a base end portion 20 fixed to a pivot portion to be described later are provided.

The inner surface of the output tip 16 is formed in a tapered shape. The output tip 16 has an electrode 17 made of copper alloy.
Is installed. This electrode 17 has an electrode base 17a.
And an electrode tip 17b, and an electrode base 17a
Is fixedly attached to the output tip 16 by fitting, and the electrode tip 17b is attached to the electrode base 17a in a replaceable manner. The wide portion 18 is formed with a concave portion 18a having an open outer side and an upper side. The inner wall portion of the wide portion 18 located inside the concave portion 18a has a pressurizing and energizing member formed of a detachably mounted energizing piece. A part 19 is provided.

As shown in FIG. 6, the left gun arm 15
Is fixed to the first pivot 33 of the first opening / closing body 32 via the insulating plate 22. Further, an insulating plate 23 is provided on the outer surface of the base end 20. The base end 20 is fixed to the first pivot 33 by four bolts 24 together with the two insulating plates 22 and 23 and the holding plate 21. Note that these bolts 24 are insulated sleeves 25.
Insulated. The right gun arm 15 is also fixed to the second pivot 37 in the same manner as the left gun arm 15. The first opening / closing body 32 includes a first pivotal support 33 and a first cylinder arm 34 integrally formed therewith.
The second opening / closing body 36 is composed of a second pivot portion 37 and a second cylinder arm 38 integrally formed therewith.

Next, the pivot mechanism 30 will be described (see FIGS. 2, 3 and 6). The pivot mechanism 30 moves the pair of gun arms 15 to a welding position where the two spot welding electrodes 17 approach each other across the workpiece W, and to the two spot welding electrodes 17.
Are pivotally supported on the main body frame 10 so as to be openable and closable over a non-welding position where the phases are separated from each other.
The upper wall portion 12u, the lower wall portion 12w, the pivot 31 and the first
The first pivot portion 33 of the opening / closing body 32 and the second
It is composed of a pivot portion 37 and the like. The first pivot 33 is formed in a U-shape when viewed from the rear, and is formed in a U-shape smaller than the pivot bracket 12, and a pair of insulating sleeves 35 are fitted in holes in upper and lower walls of the first pivot 33. , A pair of upper and lower pivot holes 33a are formed, and the inner diameter of the insulating sleeve 35 is formed to be substantially the same diameter as the pivot shaft 31.

The second pivot portion 37 is formed in a rectangular parallelepiped shape.
An insulating plate sleeve 39 is fitted in the hole of the second pivotal support 37 in a direction perpendicular to the plane to form a pivotal support hole 37a. The inner diameter of the insulating sleeve 39 is formed to be substantially the same as the pivot shaft 31. ing. The first pivot portion 33 is rotatably mounted between the upper wall portion 12 u and the lower wall portion 12 w of the pivot bracket 12 in an inverted U-shape with respect to the pivot bracket 12, and the second pivot portion 37.
Is rotatably mounted between upper and lower walls of the first pivot portion 33, and the pivot shaft 31 has a vertical pivot hole 27 (which is composed of pivot holes 12a, 33a, 37a). It is inserted and installed. The first pivot 33 and the second pivot 37
Is rotatably mounted on the pivot 31 via insulating sleeves 35 and 39.

The large diameter portion at the upper end of the pivot shaft 31 is
b, the pivot shaft 31 is locked, and the key plate 40 mounted on the upper surface of the pivot bracket 12 restricts the pivot shaft 31 from moving upward. The base end 20 of the left gun arm 15 is fixed to the side of the first pivotal support 33 via an insulating plate 22,
The base end 20 of the right gun arm 15 is fixed to the side of the pivot 37 via an insulating plate 22.

Next, the opening / closing drive mechanism 41 will be described (see FIGS. 2 to 5). The opening / closing drive mechanism 41 drives the pair of gun arms 15 to open and close between a welding position and a non-welding position, and includes a first opening / closing body 32, a second opening / closing body 36, an air cylinder 42, and an air cylinder. It comprises a piston rod 43 extending from 42. The first cylinder arm 34 of the first opening / closing body 32 is formed in a U-shape in a side view, and is formed integrally with the first pivot support 33. A pair of first connecting portions 34a is provided on upper and lower walls of the first cylinder arm 34.
Is provided, and the air cylinder 42 includes a pair of first connecting portions 3.
4a, it is rotatably connected through a pivot piece 44. A spring is mounted inside the air cylinder 42 to urge the piston in a piston rod retreating direction.

The second cylinder arm 38 is formed in a square rod shape, and is formed integrally with the second pivot 37. The second cylinder arm 38 is provided with a second connection portion 38a, and a connection recess is formed in the second connection portion 38a, and the distal end of the piston rod 43 of the air cylinder 42 is mounted in the connection recess. , And is connected to the second connecting portion 38a by a joint pin 42b so as to be horizontally rotatable. Further, in order to adjust the interval between the pair of electrodes 17 at the time of the non-welding position, a locking plate 45 for regulating the positions of the first cylinder arm 34 and the second cylinder arm 38 is provided,
The locking plate 45 is fixed to the base plate 11, and the first cylinder arm 34 and the second cylinder arm 38
In each of the non-welded states, a locking bolt 46 that comes into contact with the locking plate 45 is mounted so as to be adjustable in position.

Next, the operation of the spot welding auxiliary gun device 1 will be described. In a state where the work W is set between the electrodes 17 of the auxiliary gun device 1 for spot welding, the spot welding gun 6 of the spot welding machine 5 applies a normal pressure to the pressurizing and energizing section 19 of the auxiliary gun device 1 for spot welding. A pressing force is applied in the same manner as in the case of spot welding, but the lever length from the pivot shaft 31 to the pressurizing and energizing portion 19 is changed to the pivot shaft 3.
Since it is about 1/2 of the lever length from 1 to the electrode 17,
A pressing force of about の of the pressing force input to the pressing and energizing section 19 acts on the pair of electrodes 17.

Therefore, the opening / closing drive mechanism 41 is configured to generate insufficient pressing force. When the spot welding is performed, the air cylinder 4 of the opening / closing drive mechanism 41 is used.
When the pressurized air is supplied to 2, the piston rod 43 is driven forward. As a result, the first cylinder arm 34 and the second
The cylinder arm 38 horizontally oscillates in the phase-separated direction, and the pair of left and right output tips 16 horizontally oscillates in the phase approach direction.
The pressing force acts on the pair of left and right electrodes 17 at the same time.

In this manner, the pressing force (for example, about 250 kg) necessary for spot welding is generated by the pressing force of the spot welding gun 6 of the spot welding machine 5 and the pressing force generated by the opening / closing drive mechanism 41. At the same time that the work W is pressed between the pair of electrodes 17, the welding current supplied from the spot welding gun 6 of the spot welding machine 5 is applied to one of the pair of electrodes 17. Part 19, one output tip 16, one electrode 17, work W, the other electrode 17, the other output tip 16, the other pressurizing and energizing section 19
, And spot welding of the welding target portion of the work W is performed.

When the spot welding is completed, the spot welding gun 6 of the spot welding machine 5 separates from the pressurizing and energizing section 19, but at the same time, the pressurized air of the air cylinder 42 is discharged, and the inside of the air cylinder 42 is discharged. The piston rod 43 is driven to retract by the spring. as a result,
The first cylinder arm 34 and the second cylinder arm 38 are driven in a phase approaching direction, and the pair of gun arms 15
It is oscillated in the phase separation direction and switched to the non-welding position. At this time, the first cylinder arm 34 and the second
The swinging position of the cylinder arm 38, that is, the swinging position of the pair of gun arms 15 is determined by the locking plate 45 and the locking bolt 4.
6 regulated.

According to the auxiliary gun device 1 for spot welding, the pair of gun arms 15 are opened to the non-welding position and the work W On the other hand, in parallel with the application of the pressing force from the spot welding gun 6 of the spot welding machine 5 and the energization, the pair of gun arms 15
The spot welding can be performed by applying a pressing force to the steel sheet. As described above, the spot welding auxiliary gun device 1 having a simple configuration can perform spot welding by effectively utilizing the pressurizing function and the energizing function of the spot welding gun 6 of the spot welding machine 5, so that equipment cost and installation space are reduced. It is very advantageous. Furthermore, the opening / closing drive mechanism 41 can apply welding force to the pair of gun arms 15 with a shortage and apply welding force as desired, thereby ensuring welding quality. In addition, since a portion of the spot welding machine 5 that is distant from the pair of pressurizing and energizing sections 19 to which the spot welding gun 6 can reach can be welded, the use efficiency of the spot welding machine 5 can be improved .

The spot auxiliary gun device according to the present invention may be used while being mounted on the pallet 9, may be used while being mounted on the work W on the pallet, or may be used on the pallet transport path. It may be provided. Further, according to the shape and structure of the work W, the scope of the present invention is not deviated from the scope of the present invention.
It is a matter of course that the spot auxiliary gun device of the embodiment can be implemented in a mode in which various changes are added.

[Brief description of the drawings]

FIG. 1 is a perspective view of an auxiliary gun device for spot welding and a welding robot according to an embodiment of the present invention.

FIG. 2 is a perspective view of the spot welding auxiliary gun device.

FIG. 3 is a plan view of the spot welding auxiliary gun device.

FIG. 4 is a right side view of the auxiliary gun device for spot welding.

FIG. 5 is a rear view of the spot welding auxiliary gun device.

FIG. 6 is a sectional view taken along line VI-VI of FIG. 3;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Auxiliary gun device for spot welding 10 Main body frame 15 Gun arm 16 Output tip part 17 Electrode 18 Wide part 19 Pressurizing and conducting part 20 Base end part 30 Pivot mechanism 31 Pivot shaft 32 First open / close body 36 Second open / close body 41 Open / close drive mechanism

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B23K 11/11

Claims (3)

(57) [Claims] 1. A spot welding auxiliary gun device for performing spot welding in cooperation with a welding gun of a spot welding welding robot, comprising: a main body frame; 1 with electrodes
The main body is configured such that the pair of gun arms can be opened and closed freely over a welding position at which the two spot welding electrodes approach each other across the workpiece and a non-welding position at which the two spot welding electrodes are separated from each other. A pivot mechanism pivotally supporting the frame; and a pair of gun arms for applying a pressure to the pair of gun arms from a welding gun of a welding robot and energizing the pair of gun arms.
A pair of pressurizing and energizing portions formed at a position distant from the spot welding electrode and the pair of gun arms are pressurized to a welding position during welding.
And a driving means including an air cylinder that performs the welding. 2. The spot welding auxiliary gun device according to claim 1, wherein a spring member for elastically biasing the pair of gun arms to a non-welding position is provided. Wherein said pair gun arm, the spot welding auxiliary gun device according to claim 1 or claim 2, characterized in that formed in the side view straight.