JPH0327748Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention is applied to a welding device that is sandwiched between a pair of electrodes of a seam welding machine and rotates and welds the workpiece by the circumferential speed due to the knurl of the electrode pair. It is something to do.

(Prior Art) In an apparatus for welding an object to be welded, such as a fuel tank, which has end plates fitted to both open ends of a cylindrical body, between a pair of electrodes of a seam welding machine, using the rotational speed of the knurls of the pair of electrodes. The center of gravity of the workpiece changes constantly, unless the workpiece has a perfect circular cross section. There is a drawback that the electrode slips relative to the electrode pair and rotates behind the electrode pair, and the welding of the seam weld line is not uniform, which impairs the quality of the weld. Nothing has been done, and at most the welding speed delay can be monitored and corrected.

(Problems to be Solved by the Invention) The present invention attempts to solve these problems by using a simple device.

(Means for Solving the Problems) The purpose of the present invention is to solve the problems mentioned in the previous section. In a device that welds a workpiece by sandwiching it between a pair of electrodes of a seam welder and using the rotational speed due to the knurl of the pair of electrodes,
A balance weight that is provided with a rod that is pivotally supported on the welding machine side and whose front end protrudes from the lower surface of the object to be welded held between the electrode pairs, and that moves the front end upward to the rear side of the axis of the rod; The present invention relates to a seam welding balancer characterized in that a cylinder is provided for timely lifting up the rear end of the bar shaft and lowering the front end thereof.

A preferred embodiment of the invention will now be described.

(Example) The object to be welded d is an example of a fuel tank for a truck, etc. Welding flanges C bent at 90 degrees are provided at both open ends of a body a having a rectangular cross section with arcuate corners. The welding edges at both ends are sandwiched from the inside and outside by the pair of welding electrodes 2 and 3 of the seam welding machine 1, and welding is performed by the pair of welding electrodes 2 and 3 rotated by the knurl. Welding electrode pair 2, 3
The edge on the opposite side supports the inside of the welding flange C by a contact roll 4.

On the side of the seam welding machine 1, a U-shaped bar 6 that can swing is supported by a shaft 5, and a balance weight 8 is mounted behind the shaft 5 of the bar 6 (to the right in FIGS. 1 and 2).
is provided, and the front end 7 on the left side of the shaft 5 is brought into contact with the lower surface of the workpiece d by means of a balance weight 8. A cylinder 9 is provided rearward (to the left) of the shaft 5 to push down the front end 7 of the bar 6 as shown by the chain line by means of a rod 10 that extends at appropriate times. The height of the shaft 5 and the cylinder 9 can be freely changed depending on the cross-sectional shape of the workpiece d.

(Function) In the present invention, the workpiece d is welded by the welding electrodes 2 and 3.
As shown in Figure 3, it rotates counterclockwise and the center of gravity is 0.
is moved to the left or right of the vertical line L of the axis of the welding electrodes 2, 3 as shown in Figures 3 and 4, and the distance between the welding electrodes 2, 3 and the front end 7 of the bar 6 is varied. ,
Depending on the fluctuation, it sometimes descends against the balance weight 8, and sometimes rises due to the balance weight 8 to support the workpiece d. Also, the object to be welded d
When replacing rod 1 of cylinder 9,
0 and lower the front end 7.

(Effects) As is clear from the above, the present invention horizontally supports the lower part of the welding electrodes 2 and 3 by the front end 7 of the bar 6 that supports the lower surface of the workpiece, and the workpiece d The balance weight 8 acts on the bar 6 and changes the center of gravity 0 of the welded workpiece d in any position, causing the welding electrode 2 , 3 to ensure stable welding quality. Furthermore, by providing a cylinder 9 that lowers the front end 7 of the bar 6 in a timely manner, replacement of the workpiece d to be welded is simplified.

[Brief explanation of the drawing]

1 to 4 show an embodiment of the present invention; FIG. 1 is a perspective view, FIG. 2 is a side view, and FIGS. 3 and 4 are action explanatory views. d → object to be welded, 1 → seam welding machine, 2, 3 → welding electrode pair, 4 → contact roll, 5 → shaft, 6 → bar,
7 → front end, 8 → balance weight, 9 → cylinder.

Claims (1)

[Claim for Utility Model Registration] An object to be welded, such as a fuel tank with end plates fitted to both open ends of a cylindrical body, is sandwiched between a pair of electrodes of a seam welding machine and welded by the rotational speed of the knurl of the pair of electrodes. In the apparatus for performing the process, a bar 6 is provided on the side of the welding machine 1, which is supported by a shaft 5, and whose front end 7 protrudes and supports the lower surface of the workpiece d sandwiched between the pairs of electrodes 2 and 3. A balance weight 8 that moves the front end 7 upward to the rear side of the shaft 5
A seam welding balancer characterized in that it is provided with: and a cylinder 9 that raises the rear end of the bar 6 from the shaft 5 in a timely manner and lowers the front end 7 of the bar 6.