JPS6239899Y2 - - Google Patents

Description

Detailed Description of the Invention The present invention relates to a seam welding device, and more particularly to a seam welding device having an improved workpiece fixing mechanism and electrode pressure mechanism.

Figure 1 is a side view of a conventional seam welding device, Figure 2
The figure is an air circuit diagram for pressurizing the electrode. In FIGS. 1 and 2, a workpiece 1 to be welded is set on a workpiece positioning table 2. In FIG. In order to hold the workpiece 1, the workpiece is held down and clamped by the workpiece presser 3 by the pressurizing cylinder 4. The work positioning table 2 is
The workpiece 1 is floated vertically by a spring 22 and a guide device 23, and the flange 25 of the workpiece 1 is lightly pressed against the lower electrode 15 by the pressing force of the workpiece holder 3.

Reference numerals 12 and 13 determine the locus of the weld line to be seam welded to the flange 25 of the workpiece 1 using a small guide for the seam weld line and a small pin.

Reference numeral 5 denotes a small device mounting base, which is coaxial with the workpiece holder 3 and is designed to be able to rotate easily and freely. The work positioning frame 6 has a bearing 7,
7', attached via arm 8 and shaft 9;
Further, the arm 8 is connected to a bearing bracket 10 by a shaft 11, so that each arm can rotate easily and freely.

Reference numeral 14 denotes an upper electrode which is lowered by an air cylinder 16 to sandwich the flange 25 and perform seam welding. Reference numerals 18 and 19 denote an upper electrode guide and a lower electrode guide, which are constructed so that the electrodes 14 and 15 can smoothly and lightly slide up and down.

Further, a frame 20 has a structure that can sufficiently withstand the pressure applied by the upper and lower electrodes 14 and 15, and is connected to the holding mechanism of the workpiece 1 by a base 21 to ensure a relative position. 24 is a jack that moves the lower electrode 15 up and down when the lower electrode 15 is worn out.

When welding the workpiece 1, the lower electrode 15
The upper electrode 14 is fixed in the vertical direction, and after adjusting and holding the workpiece with such force that the flange of the workpiece lightly contacts the lower electrode 15 with the workpiece presser 3, the upper electrode 14 is pressed down with the pressure adjustment valve 27 (see Fig. 2). Adjust the pressure and pressurize. In FIG. 2, 26 is a direction switching valve that switches between pressurizing and releasing the upper electrode; 28
is a pressure gauge.

However, the following problems have been pointed out in the conventional device configured as described above.

When holding down the workpiece 1, it is necessary to press the workpiece vertically with the pressure cylinder 4 with a force that overcomes the spring 22, and to make delicate adjustments so that the flange 25 lightly touches the lower electrode 15. If the pressing force of the pressurizing cylinder 4 is too strong or too weak, the flange 25 will not come into contact with the electrodes 14, 15 at right angles, which may cause welding defects. Therefore, the force for holding the workpiece cannot be made too strong.

The flange 25 of the workpiece is connected to the upper and lower electrodes 14, 15.
Because welding is performed while clamping and pulling, if the above clamping force is weak, work 1 will shift and the weld line will come off the flange or the trajectory will shift. When welding while rotating a workpiece, the workpiece is swung around, which adds inertia to the workpiece, making it more likely to shift and causing welding defects.

When the electrodes are worn out due to welding or shaved off for electrode shaping, the diameters of the electrodes 14 and 15 become smaller. Therefore, the vertical positions of the electrodes 14 and 15 must be adjusted individually according to the workpiece 1.

The distance from the rotation axis of the workpiece positioning table 2 and the small device mounting table 5 to the electrodes 14 and 15 changes depending on the shape of the workpiece 1. Therefore, the spring 22
Even if the clamping force is delicately adjusted, an eccentric load will be applied to the workpiece pedestal 2 and the fragile device mounting base 5, and the flange 25 and the electrode will not be pressurized at right angles, which may cause the workpiece to shift and cause the welding trajectory to shift. .

The purpose of the present invention is to solve the problems of the conventional device described above, to be able to securely hold the workpiece, to provide excellent welding quality, and to facilitate the adjustment of the device.
The purpose of the present invention is to provide a seam welding device with high work efficiency.

The seam welding device of the present invention includes a workpiece holding mechanism and disc electrodes arranged in pairs above and below, wherein the workpiece holding mechanism holds the placed workpiece at a constant height. a workpiece positioning table capable of pressing the workpiece placed on the workpiece positioning table downward; It is characterized by being provided with an air cylinder for causing

Examples will be described below with reference to the drawings.

FIG. 3 is a side view of the apparatus according to the present invention, and FIG. 4 is an air circuit diagram thereof.

In the apparatus shown in FIG. 3, the workpiece positioning table 2 and the small device mounting table 5 are integrated to form a small device mounting table 5', on which the workpiece positioning table 2' is mounted.

Similarly to the upper electrode 14, a lower electrode guide 19 and an air cylinder 17 are attached to the lower electrode 15, and the workpiece 1 can be firmly moved up and down by the workpiece positioning table 2' and the workpiece holder 3 without floating up and down. Fixed. Also, electrodes 14, 15
is configured so that it can be followed according to the workpiece 1. In this case, the upper and lower electrodes 14 and 15 are connected to pressure regulating valves 24a and 24'a with check valves 24a and 24'a so that there is no difference in the force of pressing the flange 15 of the workpiece due to gravity, etc.
4 and 24', the upper and lower sides are balanced so that the flange 25 is clamped with the same force.

The rest of the structure is the same as in FIGS. 1 and 2, and the same parts are designated by the same reference numerals.

In the seam welding device configured in this way, there is no floating of the workpiece 1, so the workpiece 1 does not shift from a predetermined position during welding, and no eccentric load is applied to the workpiece 1, so the welding There is no risk of line misalignment or welding defects. Further, there is no need to delicately adjust the contact between the workpiece 1 and the electrodes 14 and 15. Furthermore, since the upper and lower electrodes 14 and 15 move up and down following the workpiece 1, there is no need to adjust the heights of the electrodes 14 and 15 individually in response to variations in the electrode diameters 14 and 15.

As detailed above, according to the seam welding apparatus of the present invention, welding quality is excellent and welding workability is dramatically improved.

[Brief explanation of the drawing]

Figure 1 is a side view of a conventional seam welding device, Figure 2
3 is a side view of a seam welding apparatus according to an embodiment of the present invention, and FIG. 4 is a diagram of the same air circuit. 1... Work, 2, 2'... Work positioning table, 3... Work holder, 4... Pressure cylinder, 6
... Work positioning frame, 12 ... Short guide, 13 ... Short pin, 14 ... Upper electrode, 15
...Lower electrode, 16, 17...Air cylinder, 2
0...Frame, 21...Base, 24, 24'
...Pressure regulating valve with check valve, 26...Direction switching valve,
27...Pressure regulating valve, 28, 28', 28''...pressure gauge.

Claims (1)

[Claims for Utility Model Registration] (1) A seam welding device equipped with a workpiece holding mechanism and a pair of upper and lower disc electrodes,
The work holding mechanism includes a work positioning table capable of holding a placed workpiece at a constant height, and a workpiece presser capable of pressing downward the workpiece placed on the workpiece positioning table. A seam welding device characterized in that the disc electrodes are provided with air cylinders that synchronously move the electrodes toward and away from each other. (2) The seam welding according to claim 1 of the utility model registration claim, characterized in that the system for supplying air to the air cylinder is provided with a pressure regulating valve in which check valves are arranged in parallel. Device.