JPH0544385U - Electrode structure of spot welding gun - Google Patents

Abstract

(57) [Summary] [Purpose] To prevent damage to the electrode holder that occurs when the electrode tip of the spot welding gun is replaced. [Structure] A rear part of a shank is fitted into a through hole provided in an electrode holder of a spot welding gun, and a cooling water path provided inside the electrode holder at this fitting part and a cooling water path penetrating inside the shank. And an electrode structure in which a cap chip is fitted to a taper-shaped tip insertion part formed on the front part of the shank, and a through hole for inserting the shank at the tip of the electrode holder of the fitting part and , The outer periphery of the rear part of the shank inserted into the inner diameter of the through hole, are detachably engaged with each other with a tapered wedge surface. Therefore, when replacing the electrode tip, the fitting part of the electrode holder is not damaged,
It is not necessary to replace the electrode holder every time the electrode tip is replaced.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an electrode structure for a spot welding gun. More specifically, it is designed so that the electrode holder will not be damaged when the electrode tip is replaced.

[0002]

[Prior Art]

 When welding with a welding gun inserted in a narrow place, the gun arm and work interfere with each other in a narrow place. To avoid this, the height of the electrode tip 43 attached to the tip of the gun arm ( H) should be as low as possible. For this reason, generally, as shown in FIG. 4, for example, an electrode in which the electrode holder 41 and the tip insertion portion 42 are integrated is used. In this case, a cooling water path 44 penetrating the shank tip is provided inside the electrode holder. Further, as shown in FIG. 3, for example, a fitting portion 35 in which the base portion of the electrode tip 33 is formed in a taper shape is inserted into the attachment hole 34 of the electrode tip penetrating the electrode holder 31 to cool the electrode holder. There is known an electrode structure in which the water passage 36 and a circumferential groove 37 provided around the base are communicated with each other.

However, in all of these conventional devices, when the electrode tip is replaced, it is removed with a strong force, so that the taper surface of the fitting portion may be damaged or damaged. This causes water leakage and electric contact damage. To avoid this, the entire electrode holder is often replaced with a new one. Since the electrode tip is frequently replaced as a consumable item, a non-negligible problem arises in that the expensive electrode holder must be replaced each time. For this reason, in the former case, if the hardness is to be increased only in the tip insertion part, an expensive material such as beryllium copper is used for the entire electrode holder.

[0004]

[Problems to be solved by the invention] The problem to be solved is that in the conventional one, if the fitting part is damaged when the electrode tip is replaced, not only the tip replacement but also the electrode holder must be replaced entirely. The point is that you have to do it.

[0005]

[Means for Solving the Problems]

 The present invention is designed so that only the tip of the electrode can be replaced without damaging the fitting part of the electrode holder.The gist of the present invention is to fit the rear part of the shank into the through hole provided in the electrode holder of the spot welding gun. In this fitting part, the IN and OUT cooling water passages provided inside the electrode holder and the cooling water passages penetrating the inside of the shank communicate with each other, and the taper formed at the front part of the shank. An electrode structure in which a cap chip is fitted into the tip-shaped tip insertion part, and a through hole for inserting the shank at the tip of the electrode holder of the fitting part and a shank to be inserted into the inner diameter of the through hole. It is at the point where it is removably engaged with each other with the taper-shaped wedge surface with the rear outer periphery.

[0006]

【Example】

 FIG. 1 is a cross-sectional view of a main part of one embodiment of the device of the present invention, in which 1 is an electrode holder attached to a gun arm of a spot welding gun, 2 is a shank inserted into the electrode holder, and 3 is a shank. A cap tip that fits on the shank.

A through hole 4 having a size into which the shank 2 can be inserted is provided at the tip of the electrode holder 1, and the inner diameter of the hole is a tapered tapered wedge surface. The shank 2 is engaged with the insertion portion 7 having a taper-shaped wedge surface formed on the outer periphery of the rear portion of the shank 2, and a force due to the wedge action acts on the fitting surface to firmly fix the two. A drill hole 5 is formed inside the electrode holder 1 to form a cooling water path for IN and OUT. Notches a and b are provided on both sides of the shank insertion portion, and a cooling water path 6 is provided through which the inside of the shank is cut out and penetrates from the notches a and b. The cooling water flowing through the gun arm is inserted into the tip insertion part 8 having a tapered surface with a tapered surface formed at the tip of the shank 2 through the drill hole 5 inside the electrode holder to the cooling water path 6 of the shank 2. It circulates to the street cap tip 3.

[0008]

[Effect of the device]

 As described above, according to the present invention, a through hole for inserting a shank is provided at the tip of the electrode holder of the spot welding gun, and the inner diameter of the through hole and the outer periphery of the shank to be inserted into the through hole have a low gradient. -Because the pad-shaped wedge surface engages detachably, even if the shank and cap tip are damaged when the cap chip is replaced, if the shank is replaced, it will be expensive as before. The entire electrode holder does not need to be replaced, and the cost can be reduced by using only the shank of a hard material instead of making the entire electrode holder of an expensive hard material. Further, since the height (H) of the electrode can be reduced, it is possible to avoid the interference of the work even in a narrow welding position, and it is possible to remarkably improve the workability and versatility of the welding.

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part showing an embodiment of the present invention.

2 is a front view showing the structure of the shank of the present invention, FIG.
The same figure (A) is a shank front view, (B) is a right side surface, (C) is a left side surface, and (D) is d of the same figure (A).
It is a -d arrow line view.

FIG. 3 is a cross-sectional view showing a conventional electrode structure.

FIG. 4 is a schematic view showing another conventional electrode structure.

[Explanation of symbols]

 1 Electrode holder 2 Shank 3 Cap tip (electrode tip) 4 Through hole 5 Drill hole 6 Cooling water path

Claims (1)

[Scope of utility model registration request] 1. A rear part of a shank is fitted into a through hole provided in an electrode holder of a spot welding gun, and IN and OUT cooling water paths provided inside the electrode holder at the fitting part and an inside of the shank. An electrode structure in which a cap chip is fitted to a taper-shaped tip insertion portion formed in the front portion of the shank, which communicates with each cooling water passage that penetrates through the tip of the electrode holder at the fitting portion. An electrode structure of a spot welding gun in which a through hole into which a shank is inserted and a rear outer periphery of the shank inserted into the inner diameter of the through hole are detachably engaged with each other with a tapered wedge surface.