JP2523549Y2 - Welding gun equipment - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a welding gun device having a gun arm which is opened and closed by an air cylinder and suitable for projection welding.

[0002]

2. Description of the Related Art Conventionally, various types of welding guns such as X type and C type having a gun arm which is opened and closed by an air cylinder are known. In this case, the air cylinder is constituted by a double-acting cylinder in which the gun arm is closed by supplying air to one pressure chamber partitioned by a piston in the cylinder and the gun arm is opened by supplying air to the other pressure chamber.

[0003]

When projection welding is performed with the above-mentioned conventional welding gun, poor welding may occur. The reason is considered as follows. That is, the projection welding, as shown in FIG.
One of the two workpieces W to be welded, one of which has a height of 1 mm to 3 mm
The projections Wa of about mm are formed, and the projections Wa are melted when the pressure is applied, and as shown in FIG.
In the conventional welding gun, in which the gun arm is closed only by the air pressure acting on the piston, when the gap between the two works W and W is reduced due to the penetration of the protrusion Wa due to the pipeline resistance of the air circuit or the like. Instantaneously delays the supply of air, the followability of the gun arm to the penetration of the projection Wa is deteriorated, and the molten metal generated by the penetration is scattered as spatter from the gap between the two works W, W,
As a result, it is considered that poor welding occurs. In view of the above, it is an object of the present invention to provide a welding gun device capable of improving the followability of a gun arm with respect to penetration of a projection and performing satisfactory projection welding.

[0004]

In order to achieve the above object,
The present invention provides a welding gun device having a gun arm which is opened and closed by an air cylinder, wherein a spring for urging a piston of the air cylinder in a closing direction of the gun arm is provided, and the gun arm is closed by air pressure and spring force acting on the piston. It is characterized by the following.

[0005]

When projection welding is performed, even if air supply is delayed when the projection is melted in, the gun arm moves to the closing side while pressing the work by the spring force, and the followability of the gun arm to the penetration of the protrusion is improved. . The spring may be provided inside the air cylinder.However, a rod extending from the piston in the closing direction of the gun arm and projecting to the outside of the air cylinder is provided, and the spring is attached to the rod projecting to the outside of the air cylinder. If a seat plate for receiving the end of the spring is provided at the end of the rod so as to be able to advance and retreat freely, the spring force can be adjusted according to the work by adjusting the seat plate.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, reference numeral 1 designates a gun body having a two-plate structure which is elongated in a vertical direction. A fixed gun arm 2 is fixed to the gun body 1 and a cam groove formed in the gun body 1. 3
An arm holder 4 which engages via a pair of upper and lower guide rollers 4a, 4a is provided, an upper movable gun arm 5 facing the fixed gun arm 2 is attached to the holder 4, and an air cylinder is provided at the lower end of the gun body 1. 6, a piston rod 8 connected to a piston 7 in the cylinder 6 is protruded above the cylinder 6, and the upper end thereof is pivotally attached to the arm holder 4. The movable gun arm 5 is moved by the vertical movement of the piston 7. By being guided by the cam groove 3, it can be freely opened and closed between an open position shown in FIG. 1A and a closed position shown in FIG. 1B. Then, the movable gun arm 5 is closed, and the workpieces W, W are clamped between the fixed gun arm 2 and the electrode tips 2a, 5a of the movable gun arm 5, as shown in FIG. Power was supplied to the fixed gun arm 2 via the power supply plate 10 fixed to the movable gun arm 1 and to the movable gun arm 5 via the ounce copper plate 11 to perform projection welding. In the figure, reference numeral 12 denotes a gun mounting bracket fixed to the gun body 1.

The air cylinder 6 opens the movable gun arm 5 by moving the piston 7 upward by supplying air to the lower chamber 6a, and lowers the movable gun arm 5 by moving the piston 7 downward by supplying air to the upper chamber 6b. The cylinder 6 is configured to be closed and double-acting.
The movable gun arm 5 is pressurized to the lower closed side by the air pressure of the upper chamber 6 b acting on the piston 7 and the urging force of the spring 13. According to this, when projection welding is performed, the movable gun arm 5 receives the urging force of the spring 13 to allow the workpiece W to work even if there is a momentary delay in the supply of air to the upper chamber 6b when the projection Wa is melted.
Is moved down while pressurizing, the followability of the movable gun arm 5 with respect to the penetration of the projection Wa is improved, the generation of spatter is suppressed, and good projection welding is performed.

In the above embodiment, the spring 13 is provided inside the air cylinder 6, but it is also possible to provide the spring 13 outside the air cylinder 6, and such an embodiment is shown in FIG. In this embodiment, the piston rod 8 is extended downward to form a rod 14 projecting below the air cylinder 6, the spring 13 is extrapolated to the rod 14, and the spring 13 is attached to the lower end of the rod 14. A pair of upper and lower adjuster nuts 1 for the seat plate 15 receiving the lower end
6 and 16 are attached so as to be adjustable up and down in the vertical direction. Also in this embodiment, the movable gun arm 5 is pressurized to the lower closing side by the air pressure of the upper chamber 6b acting on the piston 7 and the urging force of the spring 13, and the movable gun arm 5 against the penetration of the projection Wa as in the above embodiment. 5 can be improved,
Further, the urging force of the spring 13 can be adjusted according to the workpiece by adjusting the movement of the seat plate 15. When a spring is provided outside the air cylinder in a welding gun that closes the gun arm by movement of the piston rod of the air cylinder toward the extension side, such as an X-type gun, the spring may be externally inserted into the piston rod.

[0009]

As is apparent from the above description, according to the present invention, the followability of the gun arm to the penetration of the projection is improved by the spring, and the projection welding can be performed satisfactorily. According to this, the spring force can be adjusted, and the spring force can be set to a value suitable for the work according to the work.

[Brief description of the drawings]

FIG. 1 is a side view of a first embodiment of the present invention,
(A) shows an open state, (b) shows a closed state

FIG. 2 is a side view of a second embodiment of the present invention,
(A) shows an open state, (b) shows a closed state

3A and 3B are cross-sectional views of a workpiece on which projection welding is performed, in which FIG. 3A illustrates a state before penetration and FIG. 3B illustrates a state after penetration.

[Explanation of symbols]

5 Movable gun arm 6 Air cylinder
7 Piston 13 Spring 14 Rod
15 Seat plate

Claims (3)

(57) [Scope of request for utility model registration] In a welding gun device having a gun arm which is opened and closed by an air cylinder, a spring for urging a piston of the air cylinder in a closing direction of the gun arm is provided, and the gun arm is closed by air pressure and spring force acting on the piston. A welding gun device characterized in that: 2. The welding gun device according to claim 1, wherein the spring is provided inside the air cylinder. 3. A rod extending from the piston in the closing direction of the gun arm and projecting to the outside of the air cylinder is provided. A spring is externally inserted into a part of the rod projecting to the outside of the air cylinder, and a rod is provided at an end of the rod. The welding gun device according to claim 1, wherein a seat plate that receives an end of the spring is provided so as to be able to move forward and backward freely.