JPS6144355Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a vacuum valve having an improved bearing mounting structure for a movable shaft of the vacuum valve. Generally, a vacuum valve is constructed by housing a pair of electrodes in an insulating container whose interior is evacuated, and having a metal bellows to enable the electrodes to be connected and separated while maintaining the vacuum. And, this bellows has a thickness of 0.1 so that it can be expanded and contracted freely.
Since it is formed into a bellows shape with a thin plate of about 0.2 mm, it is susceptible to expansion and contraction movements in irregular directions, so when the vacuum valve is incorporated into the operating mechanism and operated, the bellows will move in a straight line. The movable shaft connected to the bellows is supported by a bearing. The movable shaft moves linearly along this bearing, and therefore the bellows can move linearly, so this bearing plays an important role, and its installation must be strong so that it does not come off during opening and closing operations. It is necessary to do so.

A conventional bearing mounting structure will be described with reference to the vacuum valve shown in FIGS. 1a and 1b.

In the figure, 1 is an insulating container, and end plates 2a and 2b attached to both ends of the insulating container constitute a vacuum container. Reference numerals 3a and 3b are electrodes, and an arc shield 5 is provided to surround the electrodes. A fixed shaft 4, which serves as an electric path, is attached to one electrode 3b, and closely penetrates the one end plate 2b, protruding to the outside to form an electric path.

Further, a movable shaft 6 is attached to the other electrode 3a to form an electric path, and a bellows 7 is provided between the movable shaft 6 and the one end plate 2a, and the movable shaft is attached to the other electrode 3a while maintaining a vacuum. 6 vertical movements are possible.

Reference numeral 8 denotes a bearing, into which a movable shaft 6 having a protrusion 6a extending in the axial direction is inserted into the outer surface, and the vertical movement of this movable shaft 6 is caused to move linearly, so that the bellows 7 expands and contracts in irregular directions. is prevented.

This bearing 8 is placed in a recess provided in the end plate 2a, and its end is held down by a disc-shaped holding plate 9 formed with a diameter larger than that of the bearing 8, and the peripheral portion of this holding plate 9 is placed on the end plate 2a. It is fixed by spot welding. To explain this spot welding method with reference to FIG. The other electrode 12 is brought into contact with the surface of the presser plate 9 at a distance of about 10 mm, a current is applied, spot welding is performed, and the bearing 8 is fixed to the end plate 2a. The shapes of the bearing 8 and the holding plate 9 are as shown in FIG. 2b and FIGS. 2c and d, respectively.

Incidentally, the dimensional relationship of the above-mentioned conventional bearing mounting portion is as follows. That is, dimension a shown in FIG. 3a was set larger than dimension b. This is because if the a dimension is made smaller than the b dimension, even if the presser plate 9 is attached, there will be a gap between the guide 8 and the presser plate 9, so the bearing 8 cannot be fixed. This is because it is impossible to make dimension a and dimension b the same in terms of processing tolerance.

Therefore, when installing the bearing 8, as shown in Fig. 3b, the end of the holding plate 9 is bent by the difference between dimensions a and b in Fig. 3a, and spot welded to the end plate 2a. It had been done.

However, if such a method is adopted, when spot welding the holding plate 9, the electrode of the spot welding machine must be pressed against it and the end of the holding plate must be bent. , which was difficult to bend and was unfavorable from the viewpoint of workability. Also, as is well known, in order to perform spot welding, pressure must be applied with an electrode, but the force required for bending naturally depends on where in the radial direction the electrode is brought into contact with the end of the disc-shaped presser plate. There was a concern that the welding conditions would be uneven and welding defects would occur.

Further, spot welding between the holding plate 9 and the end plate 2a is normally performed at several equally spaced locations on the circumference (for example, four equally spaced locations), but if the holding plate is disc-shaped as in the past, This has disadvantages in that it is difficult to position the welding location, which tends to result in uneven welding, and is also difficult to work with. If the welding points are uneven, the stress applied to the welded portion will be uneven when the movable shaft is operated, which is also undesirable because the stress will be concentrated on a specific welded portion.

The present invention was proposed in order to eliminate the above-mentioned conventional drawbacks, and includes a presser plate that facilitates pressure welding to the presser plate during spot welding and allows for easy positioning of the welding location. It is an object of the present invention to provide a vacuum valve which has good workability and enables reliable mounting of a bearing against welding.

An embodiment of the present invention will be described below with reference to the drawings. FIG. 4 is a plan view of the guide attachment part according to the present invention. A feature of this figure is that notches 9a and 9b are provided on the outer periphery of the presser plate 9.
That is, there are two notches 9a adjacent to each other at positions 90° apart from each other on the outer periphery of the presser plate 9.
9b is provided. For this reason, these notches 9a, 9b
A protrusion 9c will be formed in between. The connection between the presser plate 9 and the end plate 2a is made at the location marked with an x on the protrusion 9c in the figure. In the above configuration, when performing spot welding, by setting the positional relationship between the two electrodes of the spot welding machine to a predetermined value in advance, it is possible to accurately position the welding point.

That is, one electrode is held in the notch 9a of the holding plate 9.
The other electrode can be placed at a predetermined position on the protrusion 9c by simply placing it on the end plate 2a along with the protrusion 9c (middle of the figure). Since this protrusion 9c is in the shape of an elongated plate, it can be easily bent by pressing the electrode of a spot welder against it, and since the position where the electrode contacts is always constant, the force required for bending is also constant. Therefore, the pressure during spot welding can be made more uniform, and stable welding can be achieved.

Further, since the presser plate 9 is usually manufactured by press working, the desired number of cutouts 9a and 9b can be equally spaced. Therefore, by aligning one electrode of the spot welding machine with the notch 9a, the spot welding position can be easily determined, and stable welding can be performed with good workability.

It should be noted that the present invention is not limited to the embodiments described above, and can be applied in various ways without changing its gist. That is, FIG. 5 shows another embodiment of the present invention.
In this embodiment, four approximately circular notches 9d are provided at equal intervals on the outer periphery of the presser plate 9. In this embodiment, one electrode of the spot welding machine is placed on the illustrated mark in the notch 9d, and the other electrode is brought into contact with the illustrated It is possible to weld between the presser plate 9 and the end plate 2a at this point. In this case as well, the same effect as described in the embodiment of FIG. 4 can be obtained.

As explained above, according to the present invention, by using a presser plate consisting of a notch on the outer periphery and a protrusion formed by providing this notch,
It is possible to perform highly reliable welding, and therefore the bearing can be firmly fixed. Therefore, the shaft can be mounted with high reliability even after many opening and closing movements, and a vacuum valve with excellent longevity can be provided.

[Brief explanation of the drawing]

Figures 1a and b are a plan view and a sectional view of a conventional vacuum valve, Figure 2a is a sectional view of the main part of Figure 1, Figure 2b is a perspective view of the bearing, and Figures 2c and d are A plan view and a sectional view of the presser plate, FIGS. 3a and 3b are explanatory views for explaining the assembly shown in FIG. 2, FIG. 4 is a plan view showing an embodiment of the presser plate according to the present invention, and FIG.
The figure is a plan view showing another embodiment of the present invention. 1... Insulating container, 2a, 2b... End plate, 3a,
3b... Electrode, 4... Fixed shaft, 5... Arc shield, 6... Movable shaft, 7... Bellows, 8... Bearing, 9... Holding plate, 9a, 9b... Notch, 9c... ... protrusion, 10 ... spot welding machine, 11,
12...electrode.

Claims (1)

[Claims for Utility Model Registration] A pair of electrodes is provided in a vacuum container consisting of an insulating container and both ends of which are closed with end plates, and at least one of the electrodes is provided with a movable shaft in order to allow the electrodes to move freely toward and away from each other. In the vacuum valve in which a bellows is installed between the movable shaft and the end plate, a bearing into which the movable shaft is inserted is engaged with the end plate, and this bearing is fixed by a retainer plate, the retainer plate A vacuum valve characterized in that a plurality of notches are provided on the outer circumferential portion of the vacuum valve, and the notches are used as positioning portions, and the protrusion formed by the notches and the end plate are fixed by welding.