JP3023929U - Electrode tip for resistance welding - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an electrode tip for resistance welding that can perform welding processing in a state where a holed part is accurately positioned and set at a place to be welded of a workpiece. [Structure] A guide pin 5 is inserted into a pin insertion hole 4 provided at the upper end of a hollow electrode tip body 1 and welded while pushing it up by compressed air supplied below a hollow portion 3 of the electrode tip body 1. In the resistance welding electrode tip configured as described above, the peripheral edge is closely held to the inner wall inside the hollow portion 3 under normal pressure, but when compressed air is supplied from the lower compressed air supply pipe 7, the compressed air supplied is hollow. A pressure-increasing valve 6 that works without leaking from the space between the inner wall of the guide 3 and slides up the hollow portion 3 is fitted to elastically support the guide pin 5 from below.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 INDUSTRIAL APPLICABILITY The present invention can always perform stable centering, and a holed part such as a nut can be correctly set in a portion to be welded of a workpiece and the welding process can be performed in an accurately positioned state. It relates to resistance welding electrode tips with guide pins.

[0002]

[Prior art]

 Insert a guide pin into the pin insertion hole provided at the upper end of the hollow electrode tip body and push it up into the hollow part of the electrode tip body with compressed air supplied through the compressed air supply pipe below to weld it. The resistance welding electrode tip with a guide pin is already known as seen in Japanese Utility Model Publication No. 54-34918 and Japanese Utility Model Publication No. 3-76671, but the conventional method The electrode tip for resistance welding uses a spring to prevent the guide pin from descending under normal pressure conditions where the push-up by compressed air has been released, or a rod and valve body are installed below the guide pin to raise the guide pin. It supplies compressed air for driving and descending, and operates in a blast type.In both cases, the structure is complicated and maintenance work is difficult. There is a problem that planted the running cost is high. In addition, there is a problem in that since the force for pushing up the guide pin is weak, there is backlash and it becomes slanted, and it is not possible to accurately position the workpiece.

[0003]

[Problems to be solved by the device]

 The present invention solves the above-mentioned conventional problems, the structure is extremely simple, maintenance work in use can be easily performed, the manufacturing cost is low, and the cost can be drastically reduced. The purpose of the present invention is to provide an electrode tip for resistance welding that can push the guide pin sufficiently and reliably even with a small force, prevent the guide pin from becoming oblique, and accurately position the workpiece. It has been completed.

[0004]

[Means for Solving the Problems]

 The electrode tip for resistance welding of the present invention, which has been made to solve the above-mentioned problems, has a guide pin inserted into a pin insertion hole provided at the upper end of a hollow electrode tip body, which is then inserted into the hollow body of the electrode tip body. In the resistance welding electrode tip, which is welded while being pushed up by the compressed air supplied through the compressed air supply pipe below, to the inner part of the hollow part under normal pressure, the peripheral edge is closely held to the inner wall, but When compressed air is supplied from the compressed air supply pipe, the compressed air supplied acts without leaking from between the inner wall of the hollow portion, slides up the hollow portion, and elastically supports the guide pin from below. It is characterized in that a boost valve is fitted.

[0005]

[Action]

 With this type of structure, although the welding process is performed with the guide pin protruding from the electrode tip body and centered, it is similar to the conventional resistance welding electrode tip of this type. In the hollow part of the electrode tip body, a booster valve is fitted so that the peripheral edge is kept in close contact with the inner wall under normal pressure, and when compressed air is supplied from the compressed air supply pipe, the compressed air supplied is supplied to the inner wall of the hollow part. Since it acts without leaking from between and rises to elastically support the guide pin from below, the guide pin is maintained in a positively pushed state in the presence of the booster valve, and the object to be welded Positioning will be done accurately.

[0006]

【Example】

 The present invention will now be described in detail with reference to the illustrated embodiment. In the figure, reference numeral 1 is a hollow electrode tip body, and the electrode tip body 1 is composed of a holder 2 and a cap 2a screwed onto the upper end thereof, and is further provided on the upper end of the electrode tip body 1. A guide pin 5 made of ceramics is provided in the pin insertion hole 4 so as to be movable in the axial direction, and the above points are substantially the same as those of the conventional electrode tip of this kind.

Further, in the present invention, a booster valve 6 capable of moving up and down in the pin insertion hole 4 is disposed below the guide pin 5, and the guide pin 5 is disposed below the electrode tip body 1. A compressed air supply pipe 7 for raising a guide pin that pushes up together with the booster valve 6 is provided. The pressure-increasing valve 6 has its peripheral edge closely contacted with the inner wall under normal pressure, but when compressed air is supplied from the lower compressed air supply pipe 7, the supplied compressed air leaks from between the inner wall of the hollow portion 3. It acts on the lower surface of the booster valve 6 without any action, and slidably moves up the hollow portion 3 to elastically support the guide pin 5 from below. Is configured to be pushed up via the boost valve 6 instead of being pushed up.

As shown in FIG. 2, the booster valve 6 shown in the embodiment has a packing member 6c in a fitting groove formed on an outer peripheral wall of a doughnut-shaped valve body 6a made of metal having a central hole 6b. The packing member 6c is made of rubber or synthetic resin elastomer having a hardness and an outer diameter such that the peripheral edge of the packing member 6c is in close contact with the inner wall of the hollow portion 3 and can be slid up by the supply pressure of compressed air. And a buffer member 6d for relaxing the contact pressure with the guide pin 5 is provided on the upper surface of the booster valve 6, so that the central hole 6b has a buffer member 6d for the upper portion with the guide pin 5. It is assumed that it is closed by a plug body 6f made of elastic material such as rubber, which is enlarged and formed, and the packing member 6c closely contacts the pin insertion hole 4 with a slight pressure supplied from the compressed air supply pipe 7. The pin insertion hole 4 can be surely raised even by compressed air. Here, the valve body 6a is formed in a donut shape and the central hole 6b is closed by the plug 6d so that the pressurizing valve 6 can be easily attached to and detached from the pin insertion hole 4 by using the center hole 6b. Therefore, in order to facilitate the attachment / detachment, the lower portion of the center hole 6b is formed as a recess 6e that is not closed by the plug 6f. Reference numeral 8 denotes a hole for introducing cooling water, which is provided in the axial direction from the lower end of the electrode tip body 1 as required.

In such a structure, compressed air is supplied from the compressed air supply pipe 7 to raise the guide pin 5 along the guide hole 3a of the cap 3 sufficiently and accurately, and When the object to be welded, for example, the through hole of the plate material and the screw hole of the welding nut are fitted to the guide pin 4 for centering and positioning, and the upper electrode (not shown) is lowered from above, the upper electrode The guide pin 5 is pushed down by the upper electrode against the air pressure so as not to interfere with the welding pressurization by the above, and the welding process is performed by pressing the object to be welded and energizing it. This type of resistance welding electrode tip is similar to the electrode tip body 1 except that the hollow portion 3 of the electrode tip body 1 is fitted with a booster valve 6 in a state in which the peripheral edge of the electrode tip body 1 is held in close contact with the inner wall under normal pressure. Compressed air from the air supply pipe 7 When air is supplied, the supplied compressed air acts without leaking from the space between the inner wall of the hollow portion 3 and rises, and the guide pin 5 inserted into the pin insertion hole 4 of the electrode tip body 1 is repulsed from below. Since the guide pin 5 is supported and lifted, the guide pin 5 maintains a positive push-up state in the presence of the booster valve 6 even with a small push-up force, and the work piece is accurately positioned at a predetermined position without rattling or slanting. It will be positioned. Further, even if the supply of compressed air from the compressed air supply pipe 7 is stopped, the booster valve 6 does not have a spring or a mechanism for returning by air to keep the peripheral edge in close contact with the inner wall at normal pressure. However, since it is always above the hollow portion 3, the next operation can be performed quickly. Also, in the work of inserting / removing the booster valve 6 into / from the hollow portion 3, it is necessary to remove the cap 2a screwed into the holder 2 and then insert or remove it at a predetermined position by using the center hole 6b of the valve body 6a. Therefore, the maintenance work can be performed in a short time and easily.

In addition, as in the embodiment, the stopper 6f for relaxing the contact pressure with the guide pin 5 is provided on the upper surface of the booster valve 6 by attaching the plug 6f of the booster valve 6 to the center hole 6b from the upper side. If provided, it is preferable that the guide pin 4 is prevented from being scratched by the cushioning action, but the plug 6f may be mounted from the lower side of the central hole 6b.

[0011]

[Effect of device]

 As is clear from the above description, the present invention has an extremely simple structure, can easily perform maintenance work during use, and also can be manufactured at a low cost with a large cost down. Even if the amount is reduced, the total pressure works properly, so the guide pin can be pushed up sufficiently and reliably, and the guide pin can be positioned accurately without the guide pin becoming inclined. . Furthermore, since the booster valve holds its peripheral edge in close contact with the inner wall at normal pressure, there is no need for a spring-type or Biston-type restoring mechanism to prevent the guide pin from descending under normal pressure conditions. It is extremely simple, maintenance work is easy, and both initial cost and running cost are low, which is economically advantageous. Therefore, the present invention has an extremely large practical value as an electrode tip for resistance welding that eliminates the conventional problems.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an embodiment of the present invention when a guide pin is raised.

FIG. 2 is a perspective view showing a packing member according to an embodiment of the present invention.

[Explanation of symbols]

 1 chip body 3 hollow part 4 pin insertion hole 5 guide pin 6 booster valve 6a valve body 6b center hole 6c packing member 6d buffer 6e recess 6f plug 7 compressed air supply pipe

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[Procedure amendment]

[Submission date] October 11, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 6

[Correction method] Change

[Correction content]

Claims (6)

[Scope of utility model registration request] 1. A guide pin (5) is inserted into a pin insertion hole (4) provided at the upper end of a hollow electrode tip body (1), and the guide pin (5) is inserted into the hollow portion (3) of the electrode tip body (1). ) In the electrode tip for resistance welding, in which the welding is performed by pushing up with the compressed air supplied through the compressed air supply pipe (7) below, the peripheral edge is held close to the inner wall inside the hollow part (3) under normal pressure. However, when compressed air is supplied from the lower compressed air supply pipe (7), the compressed air supplied acts without leaking from between the inner wall of the hollow part (3) and slides on the hollow part (3). Booster valve that rises and elastically supports the guide pin (5) from below
An electrode tip for resistance welding, characterized in that (6) is fitted. 2. A shock absorber (6d) for relaxing contact pressure with a guide pin (5) is provided on the upper surface of the booster valve (6).
The electrode tip for resistance welding according to 1. 3. A pressurizing valve (6) is provided with a central hole (6b), and the central hole (6b) is enlarged to form a buffer body (6d) with a guide pin (5). 1) or 2)
The electrode tip for resistance welding according to 1. 4. The resistance welding electrode tip according to claim 3, wherein a lower portion of the center hole (6b) is formed in a recess (6e) which is not closed by the plug (6f). 5. The booster valve (6) has a packing member (6c) mounted in a fitting groove formed in an outer peripheral wall of a valve body (6a), and a peripheral edge of the packing member (6c) is a hollow portion (3). (1) or (2) or (3) or (4) is slid upward while the peripheral edge is in close contact with the inner wall
The electrode tip for resistance welding according to 1. 6. The packing member (6c) is a ring having a circular cross section having a hardness and an outer diameter such that the peripheral edge of the packing member (6c) is in close contact with the inner wall of the hollow portion (3) and can be slid up by the supply pressure of compressed air. Item 6. The electrode tip for resistance welding according to Item 6.