JP2001347380A - Removing device for electrode chip for resistance welding - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a removing device having a simple structure with which an electrode chip is removed from a shank without scratching or deforming the shank or the electrode chip. SOLUTION: A first and a second thin parts 9 and 10 of a removing device 20 are inserted between the shank 2 of a welding electrode, which is composed of the electrode chip 3 engaged in the tip of the shank 2, and the electrode chip 3. The first and the second thin parts 9 and 10 are pressed together by a spring 13 so that the thin parts are brought into a close contact. An insertion part 16 is moved by turning a handle 15 downwards so that the first member 11 and the second member 12 are separated from each other. Thus the first and the second thin parts 9 and 10 are brought into contact in their faces with the shank 2 and the electrode chip 3, and a pressure is vertically applied on the contact surfaces. Thus the shank 2 and the electrode chip 3 are separated and the electrode chip 3 is removed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for removing an electrode tip for resistance welding.

[0002]

2. Description of the Related Art A resistance welding apparatus used for spot welding has a structure in which an electrode tip 3 is detachably taperedly fitted to a tapered tapered portion 5 at the tip of a cylindrical shank 4 as shown in FIG. is there. When the number of welding points increases, the tip of the electrode tip wears out, is gradually crushed and deformed, and an alloy layer (eg, a galvanized layer) of the material to be welded adheres due to heat, resulting in sludge on the electrode tip surface. Or forming a layer. When abrasion, deformation, or formation of a sludge layer occurs at the tip of the electrode tip, adverse effects such as a decrease in welding strength and an inability to perform uniform welding occur. Therefore, when a certain welding point is reached, the electrode tip is withdrawn from the shank and replaced with a new electrode tip. The used electrode tip is regenerated by turning or the like, and is used again.

[0003] The method of extracting the electrode tip from the shank is as follows: a) The electrode tip and the shank are respectively inserted with pliers, pliers, a pipe wrench, or the like, and extracted. B) As shown in FIG. 2 and between the electrode tip 3 and pull out (for example, actual open flat 7-334).
71), c) as shown in FIG. 6, a method of repeatedly shaking the electrode tip 3 from the side surface with a hammer 32 and pulling it out (see, for example, JP-A-6-170553) is known. I have.

[0004]

However, the above technique has the following problems.

In the method (a), the electrode tip and the shank are damaged or deformed, so that the electrode tip cannot be regenerated or the shank needs to be repaired.
Also, when a number of resistance welding devices are arranged close to each other, it is difficult to remove them by colliding with the adjacent device, or the adjacent device may be damaged.

According to the method (b), when inserting the forked wedge-shaped tool or removing the electrode tip by the lever principle after insertion, the tool hits only a part of the shank or the electrode tip, and the tool hits. Parts are damaged or deformed.

In the method (c), the fitting taper is damaged, and a problem occurs in the next fitting.

The present invention has been made in view of the above points, and an object of the present invention is to provide a detaching device having a simple structure for removing an electrode tip from a shank without damaging or deforming the shank or the electrode tip. That is.

[0009]

In order to achieve the above object, according to the present invention, there is provided a structure which is inserted between a shank and an electrode tip, comes into surface contact with the shank and the electrode tip, and is removed by applying pressure vertically. Device.

Specifically, the invention according to claim 1 is an apparatus for removing a resistance welding electrode tip taperly fitted to a shank from the shank, wherein the shank comprises:
The electrode tip has a large-diameter portion and a small-diameter tapered portion that follows the large-diameter portion through a step, and the electrode tip has an axial gap between the large-diameter portion and the large-diameter portion of the shank. The shank is fitted into the tapered portion of the shank, is inserted into a gap between the large-diameter portion of the shank and the electrode tip, and comes into surface contact with the large-diameter portion and the opposite end face of the electrode tip. A device for removing an electrode tip for resistance welding, comprising a pressurizing means for applying pressure perpendicularly to both end faces so that the tip comes out of a shank.

The welding electrode comprises a shank 2 and an electrode tip 3, as shown in FIG. The shank is composed of a large diameter portion 4 and a small diameter tapered portion 5. Since the diameter of the tapered portion is smaller than the diameter of the large diameter portion, a step 21 is formed on the surface at the tip of the large diameter portion. .

On the other hand, regarding the shape of the electrode tip, the surface 7 used for welding has a shape (a hemispherical shape in FIG. 1) corresponding to the use of the welding, and the base surface 6 on the opposite side is formed. Has a hole 8 in which the tapered portion is fitted. The shank and the electrode tip are tapered and
There is a gap between the step of the large diameter shank and the base end face of the electrode tip.

The pressurizing means of the removal device of the present invention is inserted between the surface of the step 21 of the shank and the base end surface of the electrode tip, and comes into surface contact with the surface of the step of the shank and the base end surface of the electrode tip. Pressure is applied perpendicular to the two faces. In this way, contact is made on the surface and pressure is applied perpendicular to that surface, so that the force does not concentrate on one part and the electrode tip is removed from the shank without damaging or deforming the shank or electrode tip. Can be pulled out.

[0014] In the removing device of the present invention, the width of the removing device in a state where the pressurizing means is inserted between the shank and the electrode tip is larger than the width of the welding device including the cooling device and the cover attached to the electrode. Preferably it is narrow. If the width of the removal device in the inserted state is smaller than the width of the welding device, remove the electrode tip without hitting the removal device even if there are other electrodes or devices near the electrodes of the welding device. Can be.

[0015] The thickness of the portion of the removal device of the present invention to be inserted into the gap of the pressurizing means should be smaller than the distance between the step surface of the shank and the base end surface of the electrode tip when inserted between the shank and the electrode tip. preferable. With such a thickness, the shank or the electrode tip does not hit at the time of insertion, so that they are not damaged. After being inserted, it may be expanded in the thickness direction so as to come into contact with the surface of the step of the shank and the surface around the fitting hole in the base end surface of the electrode tip.

According to a second aspect of the present invention, in the first aspect, each of the pressurizing means has a contact surface in surface contact with a large diameter portion of the shank and an opposite end surface of the electrode tip. An electrode for resistance welding, comprising: a pair of contact members provided so as to be able to be separated from each other; and a driving means for driving both of the contact members in the direction of separation so as to apply pressure vertically to the opposed end surfaces. It is a chip removal device.

According to such a configuration, since the structure is very simple, manufacturing and maintenance management are simplified.

[0018] Regarding the portion of the pair of contact members that is inserted into the gap between the shank and the electrode tip, the distance between the respective contact surfaces is preferably smaller than the distance between the step surface of the shank and the base end face of the electrode tip. However, the thickness and shape of other portions are not particularly limited. It is preferable that the portion driven in the separation direction by the driving means is reinforced so as to withstand the driving force.

The driving means for driving both contact members in the direction of separation is not particularly limited. It may be driven by an air cylinder, a motor, or the like.

Here, the two contact members are combined so as to be separated from each other by a predetermined distance in the shank axis direction and cannot be separated by guide pins perpendicular to the contact surfaces of the two contact members. A pair of insertion portions which are inserted from both sides between them and each have a dimension in the direction perpendicular to the shank axis larger than the dimension in the direction of the shank axis; It is preferable that the contact member be converted into an axial force to separate the two contact members. If the contact member and the driving means have such a structure, the purpose of removing the electrode tip can be achieved with a very simple mechanism. Since the pair of contact members are inseparably combined by the guide pins, one of them does not come off and fall. Since the size of the pair of insertion portions of the handle is larger in the direction perpendicular to the shank axis (this is also the direction of insertion into the gap between the shank and the electrode tip) than the size in the direction of the shank axis, the two insertion portions are When rotated between the contact members, the insertion portions come into contact with each other so as to separate the contact members, and apply pressure.

Further, it is preferable that the pressure means has a forked shape. This is because a bifurcated shape can be easily inserted, and the shank and the electrode tip can be removed from both the bifurcated portions and pressure can be applied, so that the electrode tip can be easily removed.

[0022]

Since the present invention has the above-described structure, the following effects can be obtained.

Since the pressing means comes into surface contact with the shank and the electrode tip and applies pressure perpendicularly to the surface to remove the electrode tip, the electrode tip is not damaged or deformed, and the processing for reproduction can be performed. It's easier, more views, and lower costs. In addition, since the shank is not damaged or deformed, there is no need to repair it, and the operation rate increases, thereby reducing the cost as a whole.

Since the pressurizing means is composed of a pair of contact members and a drive means for separating the two contact members, the structure is simple, easy to use, and the cost is reduced.

[0025]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is an exploded view of the detaching device 20 according to the embodiment of the present invention. The device 20 includes a first member 11 and a second member 12 that are a pair of contact members, a handle 15 that is a driving unit that drives these members in a separating direction, and an insertion portion 1.
6 is provided. Insert part 16 is handle 1
5 is formed at the tip.

The first member 11 and the second member 12 are bifurcated and include first and second thin portions 9 and 10.
The first and second thin portions 9 and 10 are urged by a spring 13 so that the surfaces thereof are in close contact with each other, and are fixed by bolts 14. The bolt 14 plays a role of a guide pin, and the first member 11 and the second member 12 move so as to separate along the axis of the bolt 14, and the bolt 14 stops so that both members do not come off. I have.

Here, the first thin portion 9 is formed so as to protrude in a flange shape on the lower surface side of the forked inner side surface of the first member 11. The second thin portion 10 is formed on the upper surface side of the second member 12 in the same shape as the first thin portion 9. Since the lower surface of the first member 11 and the upper surface of the second member 12 are assembled so as to overlap with each other, the first and second thin portions 9 and 10 come into close contact with each other.

On the other hand, the handle 15 is in the form of one long plate, one end of which is bifurcated, and the tip of which protrudes so as to face each other to form an insertion portion 16. When the surfaces of the first and second thin portions 9 and 10 are in close contact with each other, the insertion portion 16 is inserted in the direction perpendicular to the shank axis rather than the dimension in the shank axis direction (this is due to insertion into the gap between the shank and the electrode tip). Direction) is larger. As shown in FIG. 3B, when viewed from the side while being inserted between the shank and the electrode tip, the insertion portion 16 has a rectangular cross section, and the horizontal side is longer than the vertical side. The handle 15 may be rod-shaped, and may have any other shape as long as it is easy to grasp.

The insertion portion 16 of the handle 15 is provided with the recesses 1 formed facing the first member 11 and the second member 12, respectively.
7 so that it does not come off.

The depression 17 of the first member 11 is
Are formed so as to cut off a part of a side formed by the outer side surface and the lower surface of the fork. The depression 17 of the second member 12 is
Similarly to the first member 11, it is formed on the upper surface side so as to face the depression 17 of the first member 11. When the lower surface of the first member 11 and the upper surface of the second member 12 are in close contact with each other, both the recesses 17 form one recess 18 as shown in FIG. The concave portion 18 holds the insertion portion 16 so as not to come off, and rotates the insertion portion 16 so that the first member 1
The first member 12 and the second member 12 are shaped so that they can be opened by applying force. Specifically, the width between the first member 11 and the second member 12 of the concave portion 18 is equal to or greater than the vertical width which is the thickness of the insertion portion 16, and the gap between the upper and lower portions of the concave portion 18 when the insertion portion 16 is rotated. Is smaller than the length of

Next, a method of removing the electrode tip 3 fitted to the shank 2 using the removal device 20 assembled as described above will be described.

As shown in FIG. 3A, between the shank 2 of the welding electrode and the electrode tip 3, the first and second thin portions 9, 10 of the removing device 20 which are in close contact with each other are inserted. FIG. 3B shows a state in which the detaching device 20 at this time is viewed from the side.
It is. In this state, since the force by which the spring 13 presses the upper first member 11 is stronger than the force by which the two plates are opened, the upper and lower first members 11 and the second member 12 remain in close contact with each other. Therefore, the thickness of the first and second thin portions 9 and 10 that are in close contact with each other is smaller than the gap between the shank 2 and the electrode tip 3, and the first and second thin portions 9 and 1 at the time of insertion are smaller.
0 does not hit the shank 2 or the electrode tip 3 and is not damaged.

Then, the handle 15 is turned up or down. In FIG. 4, it is rotated downward. By doing so, the two members are moved so that the insertion portion 16 opens between the first member 11 and the second member 12. At this time spring 1
3 shrinks. Then, the first and second thin portions 9 and 10 are in surface contact with the shank 2 and the electrode tip 3, and pressure is applied vertically to the contact surface, so that the shank 2 and the electrode tip 3 are separated.
Thus, the electrode tip 3 is removed.

[Brief description of the drawings]

FIG. 1A is a view in which a shank and an electrode tip are fitted, and FIG. 1B is a view in which the electrode tip is detached from the shank.

FIG. 2 is an exploded view of the apparatus according to the embodiment of the present invention.

FIG. 3A is a front view in which a removing device is inserted between a shank and an electrode tip, and FIG. 3B is a side view of the removing device inserted.

FIG. 4 (A) is a front view in which a shank and an electrode tip are removed, and FIG. 4 (B) is a side view of an inserted removal device.

FIG. 5A is a front view in which a conventional forked wedge-shaped tool is inserted, and FIG.

FIG. 6 (A) is a front view in which a conventional repeated impact hammer is applied to an electrode tip, and FIG. 6 (B) is a top view.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Resistance welding apparatus 2 Shank 3 Electrode tip 4 Large diameter part 5 Tapered taper part 6 Electrode tip base end face 7 Electrode tip welding surface 8 Fitting hole 9 First thin part 10 Second thin part 11 First member 12 Second member 13 Spring 14 Bolt 15 Handle 16 Insertion part 17 Depression 18 Depression 20 Detachment device 21 Step at tip of shank cylindrical part 31 Bifurcated wedge-shaped tool 32 Repeated hammer

Claims (2)

[Claims] 1. A device for removing an electrode tip for resistance welding taper-fitted to a shank from the shank, wherein the shank has a large-diameter portion and a small-diameter taper taper connected to the large-diameter portion via a step. The electrode tip is fitted into the tapered portion of the shank so that an axial gap is formed between the electrode tip and the large-diameter portion of the shank. It is inserted into the gap between the large-diameter portion and the electrode tip, makes surface contact with the opposite end face of the large-diameter portion and the electrode tip, and applies pressure perpendicular to both end faces so that the electrode tip comes off the shank. A device for removing an electrode tip for resistance welding, comprising pressure means. 2. The pressurizing means according to claim 1, wherein each of the pressurizing means has a contact surface that comes into contact with a large-diameter portion of the shank and an opposing end surface of the electrode tip, and is provided so as to be separated from each other in a shank axial direction. An apparatus for removing an electrode tip for resistance welding, comprising: a pair of contact members; and driving means for driving both contact members in a direction of separation so as to apply pressure vertically to the opposing end surfaces.