JPS5875721A - Vacuum valve - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Technical Field of the Invention The present invention relates to a vacuum/group using a modified bearing for slidingly guiding a movable shaft.

(b) Prior Art In general, vacuum pulp is equipped with at least a pair of electrodes that can be moved toward and away from each other in an insulated container with a vacuum inside. The electrode is movable and is airtightly attached to an insulating container via a metal bellows. Since the pegs are made of a thin metal plate with a KO of about 91 to 0.2 mm and are formed in a hollow shape so that they stretch as the movable shaft moves, excessive twisting is prevented. It is sensitive to force, and when assembling the assembled vacuum pulp into the operating mechanism body, the movable shaft to which the bellows is attached must be assembled by twisting, which requires extreme care and is difficult to manufacture. . When excessive torsional force is applied, deformation strain occurs in the bellows, which reduces the opening/closing life of the vacuum valve and causes vacuum breakage. Therefore, as a means to prevent the bellows from twisting, the movable shaft has a hexagonal cross-section, and the bearing that is fixed to the insulating device opposite to this and that slides and guides the movement of the movable shaft also has a hexagonal hole to connect the two. There is a means of engaging. that's the first
Referring to FIGS. (a) and (a), an electrode 1 is disposed facing a fixed electrode (not shown), and is fixed to the tip of a movable shaft 2 that serves as an electric path. The movable shaft 2 has one end of a bellows 3 peeled off, and is inserted into a bearing 4 and slidably guided in the axial direction so that it can be opened and closed. Reference numeral 5 denotes an end plate constituting a part of the insulating container, to which the bearing 4 is fixed. With such a configuration, the bellows has a torsion-preventing effect because the hexagonal diagonal portions 41 of the movable shaft 2 and the bearing 4 protrude, so even if a torsional force is applied to the movable shaft 2, the bearing 4
receives that force, so no torsional force is applied to the bellows 3. However, since the portion of the bearing 4 and the movable shaft 2 that slides in the axial direction is in an embedded state, the pressure inside the bellows S changes greatly due to the volume change accompanying the movement of the movable shaft 2. 4IK When the movable shaft 2 is opened, that is, when the bellows 3 is contracted, the air inside the bellows 3 is swamped due to the sudden change in volume, resulting in a very small amount of sliding between the movable shaft 2 and the bearing. The pressure inside the reeds, Perot, and IeB will rise just because of the gap. When the pressure inside the bellows s increases in this manner, the bellows t8 formed of a thin plate cannot withstand the strength, reducing the opening/closing life of the vacuum pulp and causing vacuum breakage. Also, in order to increase the pressure resistance of the bellows 3, the wall thickness may be increased, but in this case, the amount of expansion and contraction will be small.
There are cases where a predetermined stroke of the movable shaft 2 cannot be obtained.

As the rated voltage has increased in recent years, the use of vacuum T4 loops has been considered to include longer strokes and reinforcement of external insulation, increasing the amount of expansion and contraction of the bellows, and using vacuum pulp during high pressure 81P61f gas. Under these conditions of use, the pressure applied to the bellows increases and the opening/closing life of the vacuum pulp is further reduced.

(c) Object of the Invention The object of the present invention is to provide a highly reliable vacuum pulp having a long opening/closing life by eliminating the above-mentioned drawbacks and preventing a rise in pressure inside the bellows.

Embodiment of the Invention An embodiment of the invention will be described below with reference to the drawings.Second
In the figure, the shape of the hole into which the hexagonal movable shaft 2 of the vacuum pulp bearing 8 is inserted is hexagonal, and each opposite side 61 of this hexagon has a circular arc portion 6b. The arc shape of this arc portion 6a is an arc shape having the same radius of curvature r centered on the thin center of the hexagon.

In this case, six gaps 6e are formed between the opposite side of the hexagonal movable shaft 20 and the circular arc portion 6b, with the hexagonal movable shaft 2 and the circular arc portion 6b serving as walls ml, and even if the peroz is contracted by opening and closing the movable shaft. The air inside the bellows can pass through this one gate 6a and be discharged, thereby preventing a rise in pressure inside the bellows. It also prevents pressure from rising.
Since the bellows has a thin wall thickness, it is possible to obtain a predetermined amount of expansion and contraction, and it is also possible to extend the stroke of the movable shaft. The reason why the arc shape of the bearing 60 is an arc centered on the thin center of the hexagon is that the outer diameter of the bearing 6 and the wall thickness of the hole are kept as small as possible, and the air flow is effectively This is rounding to increase the area. However, a circular arc with the center axis of a hexagon in the middle is easy to process, and has the advantage of being easily manufactured using a general-purpose processing machine.

The radius of curvature r of this arc is selected to be larger than the distance H across opposite sides of the hexagon and 4 smaller than the diagonal distance H, but it is most desirable to have a value approximately in the middle of these values.

(,) Effects of the Invention As described above, according to the present invention, the hole of the vacuum pulp bearing is hexagonal, and the opposite side of this hexagon is provided with an arcuate portion to provide air relief. Prevents internal pressure from increasing,
We can provide highly reliable vacuum pulp with a long opening/closing life.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing a conventional vacuum pulp bearing part, (a) is a front view, (b) is a plan view, and Fig. 2 is a diagram showing a vacuum/4 lube bearing part, which is an embodiment of the present invention. In the figures shown, (@) is a front view, and (b) is a plan view. 1... Electrode, 2... Movable shaft, 1... Bellows, 4
... Bearing, 5... End plate, e... Hexagonal bearing, 61
...1 opposite side of hexagon, gb...circular part, 6c...-Ichinoseki. Figure 1 (b) Figure 2 (a)

Claims (1)

[Claims] At least one pair of electrodes facing each other and movable toward and away from each other is housed in an insulating container, at least one electrode is fixed to a hexagonal movable shaft, and this movable shaft is airtightly attached to the insulating container via a bellows! A bearing having a hexagonal hole connected to the shaft and slidingly guiding the movable shaft is fixed to an insulating container, and in a nine-vacuum pulso, a circular arc centered on the axis of the hexagonal movable shaft is formed on each opposite side of the hexagonal shape of the bearing. Vacuum pulp is characterized by nine parts.