JP2855494B2 - X type welding gun - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-type welding gun used for additional welding of an automobile body.

[0002]

2. Description of the Related Art There are two types of welding guns: an X-type welding gun in which a pair of gun arms supported by a common pivot are opened and closed by a pressure cylinder provided between the tail ends of both gun arms; There is a C-type welding gun in which a movable gun arm attached to a piston rod of a pressurizing cylinder is opposed to a fixed gun arm fixed to the cylinder body. In a conventional X-type welding gun, a pair of gun arms are provided so as to face both sides in a pressing direction with respect to a work, and an electrode tip attached to a tip of both gun arms when both gun arms are closed so as to approach each other. The striking point of the work is pressed and clamped between them.

[0003]

When the conventional X-type welding gun is used for welding an opening flange or the like inside the outer edge of a work, one of the gun arms is used for the front side space of the work and the other gun arm is used for the welding. It is necessary to advance inward from the outer edge of the work so as to face the space behind the work respectively.Even if there is an obstacle in only one side of the work, the welding gun can not advance any further, making it impossible to perform welding Also, when moving the welding gun to weld multiple spots on the opening flange, if there is an obstacle in the gun movement path in one side of the work, once the welding gun is retracted outward to cross the obstacle If the work is not efficient, the efficiency will be worse, and if there is a bulge on the outer edge of the work, the pair of gun arms must be opened wider than the normal opening / closing stroke to move the welding gun forward and backward. The no longer obtained, will have to use a complex that with a stroke switching mechanism as welding gun. When the opening flange of the work is welded with the C-type welding gun, even if there is an obstacle in the front and back sides of the work, for example, the space on the back side, the welding gun can be moved in the space on the front side of the work, so that the above-described problem does not occur. However, since the entire gun body including the pressurizing cylinder needs to enter the front side space of the work, it cannot be applied when the front side space of the work is not widely opened, and the use is limited. Further, the wheel arch portion A ₁ of the rear wheel house A motor vehicle bodies, as shown in FIG. 2, although the conventional X-type welding gun is welded with C-type welding gun shown in phantom in FIG can not cope In this case, a part of the gun main body enters the wheel house A, so that it is easy to cause interference with the vehicle body. In view of the above, the present invention provides an X-type welding gun having the same advantages as the C-type welding gun and requiring less space for interference escape than the C-type welding gun. The purpose is.

[0004]

In order to achieve the above object,
The present invention relates to an X-type welding gun having a pair of gun arms extending forward by being supported by a common pivot, wherein both gun arms are juxtaposed on one side in a pressing direction with respect to a work, and
At the front end of the gun arm, a first electrode tip that comes into contact with the workpiece from one side is attached, and at the front end of the other second gun arm, a bent portion that extends in the longitudinal direction of the first electrode tip is formed. A second electrode tip facing the first electrode tip is attached to the tip.

[0005]

Since a pair of gun arms are arranged side by side on one side in the pressing direction with respect to the work, if there is a space for moving the gun arm on one side of the work, for example, the space on the front side, there is an obstacle in the space on the back side. Can also move both gun arms to any position on the work in the space on the front side. Then, when the distal ends of both gun arms reach the opening inside the work, the bent portion of the second gun arm is inserted into the opening, and the distal end of the bent portion is turned around the back side of the work, so that the first electrode chip is connected to the work. And the second electrode tip is positioned on the back side of the work, and the opening flange is pressed and clamped by the two electrode tips from the front and back to perform welding. Also, the wheel arch portion of the rear wheel house of the vehicle body can be welded with the bent portion of the second gun arm wrapped around the back side of the wheel arch portion. In this case, only the front end portion of the gun arm needs to be inserted into the rear wheel house. Since there is no need to insert the gun body into the rear wheel house unlike a C-type welding gun, there is no problem of interference with the vehicle body. By the way, when welding the flange portion on the near side when viewed from the outer edge of the work at the opening of the work, the bent portion of the second gun arm is formed so as to be located forward of the front end of the first gun arm, and the first and second gun arms are formed. If the mounting position of both electrode tips is located behind the bent part, the bent part is located in front of the flange part, and the flange part can be pressed and clamped by the two electrode tips. When welding the flange portion and the lateral flange portion, if the gun arm is kept facing forward, the bent portion interferes with the flange portion and the electrode tip cannot press and clamp the flange portion. In this case, the bent portion of the second gun arm is
It is formed so as to be located behind the front end of the gun arm, so that the mounting positions of the first and second electrode tips are on the front side of the bent portion, or the bent portion of the second gun arm is located beside the front end of the first gun arm. If it is formed so as to be located on one side in the direction and the mounting position of the first and second electrode tips is on the other side in the lateral direction of the bent portion, the flange portion on the back side with the gun arm facing forward or The lateral flange portion can be pressed and clamped between the two electrode tips without causing interference of the bent portion with the flange portion. Thus, various welding locations can be accommodated by changing the positional relationship between the bent portion and the electrode tip.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, reference numeral 1 designates a gun bracket attached to an operating end of a robot. A pair of gun arms 3, 4 extending forward on a pivot 2 attached to the bracket 1 are pivoted at their rear ends. The pressurizing cylinder 5 is attached to a lever portion 3a extending to the rear end of one of the first gun arms 3, and the piston of the cylinder 5 is attached to a lever portion 4a extending to the rear end of the other second gun arm 4. The rod 5a was connected via the link 5b, thus constituting an X-type welding gun which was opened and closed by the cylinder 5. In order to prevent swinging of the two gun arms 3 and 4 due to their own weight, springs 7 and 7 for holding the two gun arms 3 and 4 in a neutral position by holding a tongue piece 6 projecting from a lever portion 4a from above and below the gun body 1. Is provided.

The two gun arms 3 and 4 are arranged on one side in the pressing direction with respect to the work, that is, on the upper side in the drawing. At the front end of the first gun arm 3, a first electrode tip 3b which comes into contact with the work from above is mounted. A bent portion 4c which bends downward and extends is formed at the front end portion of the 2-gun arm 4, and a second electrode chip 4b facing the first electrode chip 3b is attached to the tip of the bent portion 4c. When the piston rod 5a of the pressurizing cylinder 5 is driven to extend downward to swing the second gun arm 4 upward, the second electrode tip 4b comes into contact with the workpiece from below, and this contact is made. The first gun arm 3 is swung downward by the contact force, and the first electrode tip 3
b comes into contact with the work from above, and the work is pressed and held between the two electrode chips 3b and 4b. In the present embodiment, the bent portion 4c is connected to both electrode tips 3b, 4b
Is formed in front of the front end of the first gun arm 3 so that the mounting position of the first gun arm 3 is on the rear side of the bent portion 4c.

[0008] By using the X-type welding gun of the above-described configuration, the electrode by wrap around the tip of the bent portion 4c on the back side of the wheel arch portion A ₁ of the rear wheel house A motor vehicle bodies, as shown in FIG. 2 chips 3b , 4b, the arch portion A ₁
Can be clamped under pressure. In this case, a C-type welding gun a indicated by a virtual line
Unlike the above, since the main body of the gun including the pressurizing cylinder 5 does not need to be inserted into the rear wheel house A, it does not easily interfere with the work, and even if the radius of curvature of the wheel arch A ₁ is small, Additional welding can be performed reliably over the entire length.

[0009] It is also possible to Zoda welding opening flange portion B ₁ of the window B in the automobile body as shown in FIG. 3 by using the X-type welding gun, C-type welding gun a in this case a virtual line shows In this case, since the gun body enters the front of the window B, the welding robot equipped with the welding gun a easily interferes with another welding robot that performs additional welding in the engine room. Such a problem does not occur because the main body portion can be positioned on the side of the vehicle body.

[0010] Figure 4 shows a state in which welding the inner flange C ₁ of the workpiece C to be set to the jig 9 is attached through a leg 9a on the jig base 8 in the X-type welding gun.
When the conventional C type welding gun having a pair of gun arms facing up and down the flange C ₁ to perform additional welding at a plurality of locations in the longitudinal direction of the work C, the lower side of the jig 9 which enters into the lower space. In order to prevent the gun arm from interfering with the leg piece 9a, the welding gun has to be retracted once at the position where the leg piece 9a is disposed, thereby lowering the work efficiency. Work C together
Through the upper space by entering the inner flange C ₁ electrode tips 3b of, since it pressurized圧挾lifting between 4b, longitudinal direction of the workpiece C without saving operation outward in the arrangement position of the leg 9a to the welding gun And the flange C ₁ can be efficiently welded by additional hitting. Further, when the gun arms 3 and 4 are moved forward and backward with respect to the work C, it is not necessary to open the gun C 3 like a conventional X-type welding gun. Becomes unnecessary.
Further, in the case of welding the flange C ₁ with C-type welding gun a, it is necessary to enter the entire gun body to the upper space of the workpiece C, the upper space of the workpiece C is not wide open upwardly Although welding cannot be performed, only the gun arms 3 and 4 need to be inserted into the upper space of the work C with the X-type welding gun, and the space for disposing the transfer equipment and the like (the range indicated by hatching in FIG. 4) and the work C The welding can be performed even if the space for the interference escape between them is narrow.

In the above embodiment, the second gun arm 4 is located above the first gun arm 3. However, as in the embodiment shown in FIG.
A slit 4d for receiving the first gun arm 3 is formed on the side of the gun arm 3 side by side or as in the embodiment shown in FIG. 6, so that the first gun arm 3 and the second gun arm 4 are horizontally may be overlap in the direction, it can be welded space be narrower as shown in FIG. 4 of the workpiece C inner flange C ₁ for interference relief According to this. In the above embodiment, the pivot 2 is located on the same plane as the pressing surface P between the electrode tips 3b and 4b. However, depending on the application, the pivot 2 is located above the pressing surface P as shown in FIG. Alternatively, the pivot 2 may be located below the pressing surface P as shown in FIG.

In the above embodiment, the electrode tips 3b, 4b
Although the mounting position of b was set to the rear side of the bent portion 4c,
As shown in FIG. 9, the bent part 4c is formed so as to be located behind the front end of the first gun arm 3, and the electrode tips 3b, 4c are formed.
b mounting position of may be such that the front side of the bent portion 4c, the opening flange portion D ₁ of the entering direction inner side of the welding gun relative to the workpiece D will be able to readily weldable According to this, Matazu 10 As shown in FIG.
Is formed so as to be located on one side in the lateral direction of the front end of the workpiece E, and the mounting position of the electrode tips 3b and 4b is located on the other side in the lateral direction of the bent portion 4c. suitable welding gun is obtained to weld an opening flange portion E _1.

[0013]

As is apparent from the above description, according to the present invention, even if there is an obstacle in the space on one side of the front and back of the work, the inner flange of the work can be welded without being obstructed by the obstacle. It has the same advantages as the C-type welding gun, and can perform welding even in a place where the space for interference escape is different unlike the C-type welding gun. Can be welded without getting the gun body into the rear wheel house, making it less likely to cause interference.
This has the effect of reducing work restrictions for preventing interference and improving workability.

[Brief description of the drawings]

FIG. 1 is a view showing a first embodiment of a welding gun according to the present invention;
(A) is a side view, (b) is a plan view

FIG. 2 is a view showing an example of use of the welding gun of FIG. 1;

FIG. 3 is a view showing another example of use of the welding gun of FIG. 1;

FIG. 4 is a view showing still another example of use of the welding gun of FIG. 1;

FIG. 5 is a view showing a second embodiment of the welding gun of the present invention;
(A) is a side view, (b) is a plan view

FIG. 6 is a view showing a third embodiment of the welding gun of the present invention;
(A) is a side view, (b) is a plan view

FIG. 7 is a side view showing a fourth embodiment of the welding gun of the present invention.

FIG. 8 is a side view showing a fifth embodiment of the welding gun of the present invention.

FIG. 9 is a side view showing a sixth embodiment of the welding gun of the present invention.

FIG. 10 is a perspective view of a main part of a seventh embodiment of the welding gun of the present invention.

[Explanation of symbols]

 2 Axis 3 First Gun Arm 3b First Electrode Tip 4 Second Gun Arm 4b Second Electrode Tip 4c Bend

Claims (4)

(57) [Claims] Claims: 1. An anteriorly extending shaft 1 supported by a common pivot.
In an X-type welding gun having a pair of gun arms, both gun arms are juxtaposed on one side in a pressurizing direction with respect to the work, and a first electrode tip which comes into contact with the work from one side is attached to the front end of one first gun arm, and the other is mounted on the other end. A bent portion extending in the longitudinal direction of the first electrode tip is formed at a front end portion of the second gun arm, and a second electrode tip facing the first electrode tip is attached to a tip of the bent portion. X
Mold welding gun. 2. The first and second gun arms are formed such that a bent portion of the second gun arm is located forward of a front end of the first gun arm.
2. The X-type welding gun according to claim 1, wherein the mounting position of the two electrode tips is located on the rear side of the bent portion. 3. The first and second gun arms are formed such that a bent portion of the second gun arm is located rearward of a front end of the first gun arm.
2. The X-type welding gun according to claim 1, wherein the mounting position of the two electrode tips is set in front of the bent portion. 4. The bent portion of the second gun arm is formed so as to be located on one side in the lateral direction of the front end of the first gun arm, and the mounting position of the first and second electrode tips is on the other side in the lateral direction of the bent portion. 2. The X-type welding gun according to claim 1, wherein: