JPH0327739Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a small welding gun mainly used for arc welding of studs.

(Prior Art) As shown in FIG. 2, in a conventional welding gun, the piston rod 1 is long, and the main spring 2 and the pull-up coil 3 are disposed on the same axis, so that the overall length L of the gun body 4 is long. Overall, it had the disadvantage of being bulky.

To this end, it is conceivable to shorten the piston rod 1 or to simply make the main spring 2 and the pull-up coil 3 smaller, but this would have the disadvantage of making it difficult to perform accurate welding.

(Technical Problem) The present invention was developed in view of the shortcomings of the conventional technology, and the technical problem is to provide a small welding gun that is small, easy to handle, and has good welding accuracy. .

(Technical means) In order to solve the above technical problem, the present invention adopts a short piston and rod assembly, and also supports the cylinder slidably by a bearing, and While the connected flange portion is brought into pressure contact with the main coil spring, inside the main coil spring,
A lifting electromagnetic coil is provided, the overall length of the gun body is shortened, and the joint of the air hose is incorporated into the gun body for ease of use.

Specifically, as shown in FIG. 1, the configuration is as follows.

Reference numeral 10 denotes a welding gun body made of synthetic resin to strengthen insulation, and a cylinder 13 into which a piston 11 and a piston rod 12 move in and out is slidable in the axial direction within the welding gun body 10 via a bearing 14. It is provided. That is, the piston 11 and the piston rod 12 move in the left-right direction within the chamber 13A of the cylinder 13, and the cylinder 13 also moves smoothly in the left-right direction via the bearing 14. 15 is a pneumatic inlet/outlet provided in the front part of the cylinder 13, and 16 is a pneumatic inlet/outlet provided in the rear part of the cylinder 13. By selectively supplying air pressure to both the pneumatic inlets 15, 16, the piston rod 12 makes timing movements in the left and right directions. .

Reference numeral 17 denotes a flange that is integrally attached to the cylinder 13 and has a contact protrusion 18 and a spring receiving portion 19 formed therein.

Reference numeral 20 denotes a contact position adjustment member disposed opposite to the contact protrusion 18 of the flange 17, and its position is adjusted by a threaded portion 21.

22 is an electromagnetic coil for pulling up the flange 1.
The flange 17 is positioned partially outside the contact protrusion 18 and the contact position adjustment member 20 of No. 7, and when the lifting electromagnetic coil 22 is energized, the flange 17 is attracted integrally with the cylinder 13 and pulled up in the direction of arrow A. .

23 is a coil-shaped main spring disposed outside the electromagnetic coil 22 for pulling, a part of which is connected to the spring receiving part 19 of the flange 17 and the fixed part 24.
It is placed between.

Thus, both the flange 17 and the cylinder 13 are constantly pushed out in the direction of arrow B by the expansion elasticity of the main spring 23.

One key point of the present invention is that by arranging the main spring 23 outside the electromagnetic coil 22, the overall length of the gun can be shortened.

Reference numeral 25 denotes a chuck having grooves in the longitudinal direction, which always provides elasticity in the direction of arrow C.

26 is a stud, and 27 is a spark shield. When the stud 26 is held between the chucks 25, a portion of the stud 26 protrudes from the front surface 27A of the spark shield 27 by a distance ΔP.

28 is a chuck adapter having the chuck 25 and is integrally connected to the cylinder 13. The distance ΔG is the gap between the contact protrusion 18 of the flange 17 and the contact position adjusting member 20, and the distance ΔL is the gap between the flange 1
7 shows the lifting distance. Therefore, ΔG=ΔP+
ΔL. ΔG=0 means that the contact protrusion 18 of the flange 17 and the contact position adjusting member 20 are in contact with each other. 29 is a stud inlet portion of the chuck adapter 28, which receives the stud 26 fed from the feed tube extension assembly 30.

31 is a feed tube for feeding the studs 26.

(effect) The above technical means works as follows.

By supplying air pressure from the air pressure inlet/outlet 15, the piston 11 and piston rod 12 move in the direction of arrow D and once stop.

At that time, Stud 26 becomes Feed Tube 3.
1. Feed tube extension assembly 30, chuck adapter 28 inlet part 2
9 and is fed into the chuck 25.

Next, when air pressure is supplied from the air pressure inlet/outlet 16, air exits from the air pressure inlet/outlet 15, so the piston 11 and the piston rod 12 move in the direction of arrow E, and the chuck 25 is expanded, as shown in FIG. Push out the stud 26 to the tip of the chuck and clamp it as shown in the figure. At that time, a part of the stud 26 is attached to the front surface 2 of the spark shield 27 by a distance ΔP.
It is made to protrude from 7A. Welding preparation is completed in this state. Next, while maintaining this state, the welding gun body 10 is brought to the welding position and the front surface 27A of the spark shield 27 is pressed until it hits the welding surface (not shown). At this time, the stud 26 is pushed into the welding gun body 10 in the direction of arrow A by a distance ΔP protruding from the front surface 27A of the spark shield 27.

In other words, the stud 26 is held between the chuck 25 and pushed by the piston rod 12, and the piston rod 12 is connected to the cylinder 13 connected to the chuck adapter 28, so that the stud 26 is connected to the welding gun body 10. Being pushed inward in the direction of arrow A means that the cylinder 13 moves in the direction of arrow A.

Distance ΔP of this cylinder 13 in the direction of arrow A
The movement of the main spring 23 is carried out smoothly by the bearing 14, and the flange 17 integrally connected to the cylinder 13 compresses the main spring 23 via the spring receiving part 19. At that time, the distance ΔG between the contact protrusion 18 of the flange 17 and the contact position adjustment member 20
(gap) decreases by distance ΔP from the initial state.

Next, when a welding start operation is performed, the pulling electromagnetic coil 22 is energized, and the flange 17 connected to the cylinder 13 is further attracted and moved in the direction of arrow A, so that the distance ΔG is 0, that is, the contact protrusion 18 of the flange 17 is moved until it comes into contact with the contact position adjustment member. At this time, the stud 26 is pulled up from the base metal surface (not shown), and the stud 26 is pulled up from the base metal surface (not shown).
An arc is generated between 6 and the base metal surface, and for a certain period of time,
After the arc is generated, the excitation to the electromagnetic coil 22 is extinguished, and the restoring force of the main spring 23 presses the stud 26 against the base metal surface, completing welding.

(Effects) The present invention has the following unique effects.

(a) Since the main spring 23 is disposed outside the electromagnetic coil 22 for pulling up, the length of the welding gun body 10 can be made as short as possible compared to conventional products.
The product can be made more compact.

(b) Since the cylinder 13 is made slidable by the bearing 14, the cylinder 13 can be moved smoothly and stud welding can be performed with high precision.

[Brief explanation of the drawing]

Figure 1 is a partial longitudinal side view of the main parts of the present invention, Figure 2
The figure is a vertical side view of a conventional product. 10... Welding gun body, 13... Cylinder, 1
4...Bearing bearing, 17...Flange, 2
2... Electromagnetic coil, 23... Main spring, 26
... Stud.

Claims (1)

[Scope of utility model registration request] A cylinder 13 having a piston 11 and a piston rod 12 is made slidable by a bearing 14, and a contact protrusion 18 of a flange 17 formed integrally with the cylinder 13 is loosely fitted into an electromagnetic coil 22 for pulling. A small welding gun in which a part of a main spring 23 disposed outside the electromagnetic coil 22 is pressed against the flange 17 while facing the contact position adjusting member 20.