JPS5828121A - Vacuum switching device - 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 The present invention relates to a vacuum switchgear, and in particular, a vacuum container is formed by closing both ends of a metal tube with insulating end plates, and a pair of electrodes are placed in the vacuum container by insulating end plates. This invention relates to a vacuum breaker which is provided with an increased external insulation strength, etc., and which is provided so as to be able to approach and separate via a pair of electrode rods introduced so as to be able to approach and separate from each other.

In general, a vacuum breaker 1B is constructed by opening both ends of an insulating cylinder made of glass or ceramics with metal shoulder plates to form a vacuum container, and 1a, in which a pair of electrodes are relatively approached from both metal end plates. It is constructed so that it can be moved toward and away from the electrodes through a pair of electrode rods that are introduced in a way that they can be moved apart, but in order to reduce the size and cost of the metal cylinder, both ends of the metal cylinder are made of insulating end plates made of ceramic. A vacuum container is formed by closing the vacuum container, and a pair of electrodes are installed in the vacuum container so as to be able to approach and separate from each other via a pair of electrode rods that are introduced from the insulating end plate so as to be able to approach and separate from each other. Proposed.

However, in the former vacuum breaker, the axial length of the insulating tube is the external insulation distance, and the vacuum breaker alone was able to pass the test voltage for each working voltage, but the latter vacuum breaker The length corresponding to the diameter of the insulating end plate is the external insulation distance, and at the same working voltage, the external insulation distance is about 1/2 of the former, so the test voltage cannot be cleared with a vacuum breaker alone. It was necessary to strengthen the external insulation to match the internal vacuum insulation strength.

The present invention was made in view of the above-mentioned problem, and its purpose is to have a strength comparable to that of the internal vacuum insulation of a vacuum container consisting of a metal tube and insulating end plates closing both shoulders of the vacuum container. It is an object of the present invention to provide a vacuum switchgear which can reduce thermal effects caused by arcing and mechanical shocks during closing and closing operations. Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a longitudinal sectional view of the @1 embodiment of the vacuum switchgear according to the present invention. In the figure, reference numeral 1 denotes an insulating case made of epoxy resin into a cylindrical shape with a bottom. Inside this insulating case 1, an IHIll of a cylindrical metal tube 2 is hermetically closed by an IM+4 plate 3.3 made of ceramic. A vacuum container is formed, and a pair of electrode rods 5 and 6 are introduced into the vacuum container from the center of the insulating end plate 3.3 so that they can approach and separate from each other. Via contact separation (contact 1Ii)
A freely provided vacuum breaker 6 guides the fixed electrode rod 6 (upper side in FIG. 1) through a hole 7 provided at the center of the bottom of the insulating case 1σ, and also connects the insulating end plate 3 on the side of the fixed electrode rod 6 to the insulating end plate 3. They are housed concentrically at an appropriate distance from the bottom of the insulating case 1.

The outer periphery of the metal tube 2, which faces the outer part near the middle of the metal tube 2 in the vacuum shield and the disconnector 6, in other words, the portion where an arc is generated due to contact and separation of the electrodes 4.4, is provided with a disconnection ItiU.
The heat dissipating member 8, which is formed into a cylindrical shape and has an outer diameter suitably smaller than the inner diameter of the insulating case 1, has its opening *T1 in FIG. 1 projecting from the open end of the insulating case 1. It is fitted. Flange portions 8a and 86 extending in the radial direction (left and right direction in FIG. A hole is provided through which the electrode rod 6 is inserted, and the outer diameter of the outwardly extending 7272 portion 8h is approximately the same as the outer diameter of the insulating case 1. The heat dissipating member 8 receives arc heat from the insulating case 1 and the vacuum barrier a6, which are integrated through the elastic body, as described later, by its elastic deformation, its own heat conduction, or heat dissipation by air flowing in and out of its hollow part. Negative effects, such as peeling of the brazed portion of the vacuum breaker 6 due to local expansion of the elastic body;
This item is used to cushion damage such as breakage of the insulating end plate 3 made of ceramic or breakage of the insulating case 1 made of epoxy resin.It has excellent thermal conductivity and insulation properties, and is flexible at room temperature. A combination of polypropylene and alumina that has a high temperature (approx.

And insulation case 1 and vacuum case 1? The cut 66 is made of silicone rubber, polybutadiene rubber, or epoxy rubber, which is made of silicone rubber, polybutadiene rubber, or epoxy rubber and has excellent heat resistance and insulation properties, and is made of silicone rubber, polybutadiene rubber, or epoxy rubber, which is cast and cured between the three insulating end plates of the movable electrode rod all. They are integrated by an elastic body 9 made of liquid rubber.

In the figure, 10 is a bellows, and 11 is an insulating case 1.
Insulation l71 at the bottom of the vacuum breaker 6 and the fixed electrode rod 6 side of the vacuum breaker 6
The backing is inserted between the fixed electrode rod 6 and the Ii plate 3, and is formed into a ring shape from rubber that is insulating and has the same degree of elasticity as the elastic body 9. Also, 12 is a fixed electrode protruding from hole 7 of insulating case 1. '
! It is a nut with 8K screws.

W, which manufactures the vacuum switchgear having the above configuration, firstly, the backing 11 attached to the fixed electrode rod 5 is sandwiched between the bottom of the insulating case 1 and the end plate 3 on the side of the fixed electrode rod 6. The vacuum breaker 6 is housed concentrically in the insulating case 1 as shown in FIG. Temporarily fix it to 1. Next, place the insulating case 1 with its opening facing upward, and
After injecting an appropriate amount of cast liquid rubber between the two and confirming that the cast liquid rubber is sufficiently liquid and free of voids, fit the heat dissipating member 8 to the outer periphery of the metal cylinder 2σ), and then heat the heat dissipating member 8 with the cam.
A movable electrode rod is placed between the inner peripheral side of the vacuum breaker 6 and the vacuum breaker 6! Injection port (not shown) provided on the flange portion 8α for casting liquid rubber with a force 1 for coating the insulated electric plate 91 (3σ) outside [Tri missing coating force 1]
Inject liquid rubber into the mold.

Then, the insulating case 1 is heated and cured by casting liquid rubber.
By integrating the vacuum breaker 6 and the vacuum breaker 6, a desired vacuum switchgear is completed. Here, the liquid level of the cast liquid rubber first injected between the insulating case 1 and the vacuum breaker 6 rises to near the opening shoulder of the insulating case 1 due to the fitting of the heat dissipating member 8σ) into the metal cylinder 2. It is something.

In the above-mentioned embodiment, a case was described in which the outer diameter of the material 8 was appropriately smaller than the inner diameter of the insulating case 1, but the invention is not limited to this.
As in the second embodiment shown in the figure, the heat dissipating member 8' may have an outer diameter that is approximately the same as the inner diameter of the insulating case 1. In such a case, the heat dissipating member B' serves as a vacuum breaker for the insulating case 1. 6 positioning can be performed.

In addition, the heat dissipating member 8.8'σ) fitted into the metal cylinder 2 may be pre-formed with an axial flow groove (not shown) on the inner peripheral portion. In such a case, the cast liquid rubber may be injected after the heat radiating member 8,8' is fitted into the metal cylinder 2.

As described above, the vacuum switchgear according to the present invention has a vacuum breaker formed by a metal cylinder and an insulating end plate that closes both ends of the vacuum container, and the outer surface of the vacuum breaker is covered with an elastic body made of cast liquid rubber. External flash value compared to that of ? 5~
It can be increased to about 10 times. In addition, since the insulation case and the vacuum breaker are integrated by an elastic body interposed between them, the mechanical shock when the vacuum breaker is turned on or off can be quickly attenuated. Brazing can prevent parts from peeling off due to fatigue. In particular, if the vacuum switchgear is a sealed type in which an insulating case and a vacuum breaker housed concentrically within the cliff case are integrated by an elastic body made of cast liquid rubber interposed between the two. In this case, the elastic body facing the arc generating part expands locally due to the heat of the arc generated by the contact and separation of the electrodes of the vacuum breaker, and this expansion acts as pressure on the vacuum container or insulating case, causing the vacuum breaker to expand. Brazing may cause parts to peel off, breakage of the ceramic insulating end plate, or breakage of the insulating case. Since the heat dissipating member formed in a cylindrical shape is fitted in such a way that its open end protrudes from the open end of the insulating case, the air in the hollow portion is circulated with the outside air and radiates arc heat. The elastic body interposed between the insulating case and the vacuum breaker does not expand locally, and the vacuum breaker σ) brazing may cause peeling of parts, breakage of the ceramic insulating end plate, or damage to the insulating case. This has the advantage that there is no risk of breakage.

[Brief explanation of the drawing]

Fig. 1 is a vertical cross-sectional view of the first embodiment of the vacuum switchgear σ) according to Himi Akeban, and Fig. 2 is the second embodiment of the vacuum switchgear according to Himi #4.
It is a half-cut sectional view of an example. 1... Insulating case, 2... Metal tube, 3... Insulating end plate, 4... Electrode, 6... Electrode rod, 6... Vacuum breaker, 8° 8'... Heat dissipation member, 9... elastic body. Figure 1 Figure 2

Claims (1)

[Claims] In a cylindrical insulating case with a bottom, both I11 of the gold plate are closed with insulating end plates to form a vacuum container, and a pair of electrodes can be moved relatively toward and away from the insulating end plates in this vacuum container. A vacuum breaker, which is provided so as to be able to come into contact with and separate from it through a pair of electrode rods introduced into the vacuum breaker, is housed concentrically with the breaker plate on the fixed electrode rod side spaced apart from the bottom of the insulating case. A heat dissipating member having a U-shaped cross section and a cylindrical shape is fitted on the outer periphery of a metal tube facing the arc generating part of the breaker so that its open end protrudes from the open end of the insulating case, The insulating case and the vacuum breaker are integrated by an elastic body made of hardened cast liquid rubber between them, such that the insulating end plate on the movable electrode side of the vacuum breaker is coated. vacuum switchgear.