JPH04184830A - Vacuum circuit breaker - Google Patents

Abstract

PURPOSE:To enhance an insulation characteristic and the installation area of a storing vessel by providing an opening part at least at a part opposite to an vertical end of a vacuum valve. CONSTITUTION:A pair of opening parts 4c, 4d opened in the U-shape upwards from the intermediate part between right and left sides are provided at a projecting insulation cylinder 4 vertically installed to a partition 21a of a box in insulation gas hermetically via an O ring 21b. Rectangular windows 4e, 4f are provided below an intermediate partition 7. A plurality of metal members 5h are embedded at an upward end face of upper-half support parts 4a, 4b of the insulation cylinder 4, and bored holes are provided on the upper outer circumference of an upper electrode 5A at the positions corresponding to the embedded metal members 4h. In a part between respective phase charging parts of respective valves 1, all the insulation gaps are in insulation gas by the opening parts 4c-4f, and an electric field is alleviated, thereby an insulation resistance value is increased.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Field of Application) The present invention relates to a vacuum circuit breaker used in particular in an insulating gas.

(Prior Art) In FIG. 5, which shows a conventional vacuum circuit breaker housed in a cubicle-type switchgear, a box 21 is provided with a door (not shown) on the front, and inside the box 21 is divided into upper and lower sections. A partition wall 21a is provided, and an insulating cylinder 22 having a substantially convex shape in a front view is placed on the partition wall 21a, and a flange portion 22 at the lower end is mounted on the partition wall 21a.
a, and the lower part of the partition wall 21a is a low-pressure operating mechanism part 2.
3, and a door 21a is fixed to the front with bolts.

In a vacuum circuit breaker configured and housed in this way,
The vacuum valve 1 is housed coaxially inside an insulating cylinder 22, and the movable side charging part 24 connected to the movable shaft at the bottom of the vacuum valve 1 is also housed inside the lower end of the insulating cylinder 22, and the upper end of the vacuum valve 1 The end plate 2 is also housed inside the upper end of the insulating cylinder 22, so that insulation is maintained by the gaps between the phases and the ground. On the other hand, the charging part for connecting an external conductor (not shown) exposed at the upper end has an elliptical cross-sectional and planar shape, as shown in FIGS.
Similarly, insulation is maintained by the air gap provided between the phases and the ground.

On the other hand, for example, in power receiving equipment with a receiving voltage of 72KV, in order to reduce the installation area,
Gas-insulated switchgear, which houses main circuit equipment such as vacuum circuit breakers and disconnectors inside a box filled with sulfur hexafluoride gas (hereinafter referred to as insulating gas), is increasingly being used.

(Problem to be solved by the invention) However, in the conventional vacuum circuit breaker, by covering the vacuum valve 1 with the insulating cylinder 22 for air insulation, the insulation distance between the phases and the ground is certainly shortened. and the insulating cylinder 22
Although it is possible to increase the mechanical strength of the insulating support by adopting it, if it is directly applied to a switchgear filled with insulating gas, the electric field inside the insulating cylinder will reduce the distance to ground and the dimension between the phases. It becomes an obstacle.

That is, the upper and lower end plates of the vacuum valve 1 and the movable side charging part 2
4 and the inner periphery of the insulating cylinder 22 is narrow, so there is a risk of dielectric breakdown due to the electric field concentrated on the end plate or the outer periphery of the movable live part. This impairs the features of the gas insulated switchgear.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a vacuum circuit breaker that can alleviate local electric field concentration, has a small external size, and reduces the installation area of the box in which it is housed, thereby making the best use of the features of gas-insulated switchgear. It is.

[Structure of the Invention] (Means and Effects for Solving the Problems) The present invention provides a vacuum circuit breaker provided in a container filled with an insulating gas and a vacuum valve housed in an insulating cylinder. By providing an opening at least in the part facing the upper and lower ends of the vacuum valve, the insulation characteristics between the vacuum valve and the ground in the insulating gas are improved, and the external size is small and the installation area of the box body is small. This is a vacuum circuit breaker that can take advantage of the features of gas-insulated switchgear.

(Example) Hereinafter, one example of the vacuum circuit breaker of the present invention will be described with reference to the drawings. However, parts that overlap with those in FIG. 5 are given the same reference numerals and their explanation will be omitted.

FIG. 1(a) is a plan view showing a state in which the vacuum circuit breaker of the present invention is housed inside a box 21 filled with insulating gas, and FIG. 1(b) is a front view of FIG. 1(a). It is a diagram.

In FIG. 1, an O-ring 2 is attached to the partition 21a of the box body 21.
The convex insulating cylinder 4, which is installed vertically in an airtight manner in an insulating gas via the insulating cylinder 1b, has a second insulating cylinder 4, which corresponds to one phase in the same figure (b).
As shown in the figure, a pair of U-shaped openings 4c and 4d opening upward from the middle of the left and right side surfaces are provided as shown in FIG. 3, which is a perspective view of the insulating cylinder 4.

This insulating cylinder 4 has an intermediate partition 7 in the middle that partitions the upper and lower parts.
, and rectangular windows 4e and 4t are provided at the bottom of the intermediate partition 7 on both the left and right sides, and a small rectangular window 4g is provided at the rear of the intermediate partition 7. A round hole 7a is formed in the center of the partition 7 for a movable energizing shaft that vertically passes through the intermediate partition 7, and support portions 4a and 4b are formed in an arc shape in the upper half of the insulating tube 4.
The opening end face of is chamfered semicircularly, and the partition 7 and the window 4e,
The end face of 4f' is also chamfered.

In FIGS. 1 to 4, the upper end of the vacuum bulb 1, in which the outer periphery of the insulating tube is housed above the partition 7 inside the insulating tube 4 with a gap, is placed in a recess formed on the lower surface of the upper electrode 5A. The fixed shaft that is inserted and passes through the center of the upper end plate 8 of the vacuum valve 1 is inserted into a small diameter counterbore provided at the center of the recess of the upper electrode 5A, and is inserted into a small diameter counterbore provided at the center of the recess of the upper electrode 5A. It is fastened to the upper electrode 5A with a bolt inserted through the hole.

On the other hand, a plurality of filler metals 4h are embedded in the upper end surface of the support portions 4a and 4b of the upper half of the insulating cylinder 4, and counterbore holes are provided in the outer periphery of the upper surface of the upper electrode 5^ at positions corresponding to the filler metals 4h. A collar 17 is inserted between the filler metal 4h and the upper electrode 4, and the upper electrode 5A is connected to the insulating tube 4 through the collar 17 with a bolt (not shown) inserted from above into a countersunk hole on the outer periphery.
is firmly fixed.

Further, the lower end of the cylindrical cover ring 1O, which is embedded in the upper end of the insulating container 1a of the vacuum valve 1 and whose upper end is brazed to the outer periphery of the upper end plate 8, is at the same height as the lower end surface 5a of the upper electrode 5^. There is.

On the other hand, a lower end plate 9 at the lower end of the vacuum valve 1 is also provided with a lower electrode 5B having the same shape as the upper electrode 5A shown in FIG. A movable shaft passing through the lower end plate 9 passes through the center of the electrode 5B, and a connection terminal 18 for external connection whose rear end protrudes rearward from the small window 4g is connected to the recess of the lower electrode 5B. ,
A bell-shaped hollow shield ring is fixed to the intermediate partition 7 at the connection between the movable shaft and the insulated operating rod 16.

Furthermore, a connecting terminal 14B having a gutter-like groove formed on the upper surface is fixed to the center of the upper surface of the upper electrode 5A with a bolt (not shown) inserted into a counterbore (not shown) in the upper surface. On the top surface, there is a hollow connection terminal 1 for tightening the round rod-shaped connection conductor 15 disposed in the box body 21 from above.
A connecting terminal 14A having the same shape as 4B is similarly fastened to the connecting terminal 14B with a bolt (not shown).

Now, in the vacuum circuit breaker configured in this way, all insulation gaps are provided between the live parts of each phase of each vacuum valve 1 shown in FIG. 1 by the openings 4c, 4d, 4e, and 4f. Since it is in gas, the electric field is relaxed and the dielectric strength value can be increased compared to a conventional vacuum circuit breaker in which a vacuum valve is inserted into an insulating cylinder.

Therefore, the phase-to-phase dimensions of the vacuum valve 1 can be reduced, so the external size can be reduced, and the installation floor area of the gas-insulated switchgear in which this vacuum circuit breaker is housed can be reduced. This is a vacuum circuit breaker that can take advantage of the

In the above embodiment, the insulating tube 4, the vacuum valve 1, and the operating mechanism section 23 were constructed to be assembled separately as shown in FIG. , the insulating cylinder 4, the vacuum valve 1 and the operating mechanism part 2
3 are each made into a unit, a square flange is provided at the lower end of the high pressure side, and a seal groove is provided in this flange.
This flange portion may be placed from above on a partition wall provided with a square hole and fixed airtightly.

Further, in the above embodiment, the openings 4c and 4d are U-shaped, but the openings may be provided only at the charging portions at the upper and lower ends of the vacuum valve 1.

[Effects of the Invention] As described above, according to the present invention, in a vacuum circuit breaker provided in a container filled with an insulating gas and a vacuum valve housed in an insulating cylinder, at least the upper and lower ends of the vacuum valve of the insulating cylinder By providing openings in the opposing parts, we have improved the insulation properties between the phases of the vacuum valve in the insulating gas and between the ground.
It is possible to obtain a vacuum breaker whose external size can be reduced and the installation area of a storage container can be reduced.

[BRIEF DESCRIPTION OF THE DRAWINGS] Fig. 1 is a diagram showing an embodiment of the vacuum circuit breaker of the present invention, in which Fig. 1(a) is a plan view, Fig. 2(b) is a front view, and Fig. 2 is a diagram showing an embodiment of the vacuum circuit breaker of the present invention. 3 is a perspective view showing the main parts of the vacuum circuit breaker of the present invention, FIG. 4 is a partial vertical sectional view of the vacuum circuit breaker of the present invention, and FIG. FIG. 2 is a diagram showing a conventional vacuum circuit breaker, in which FIG. 1A is a plan view and FIG. 1B is a front view. 1... Vacuum valve 4... Insulating tube 4c, 4
d, 4e, 4f...Opening 23...Operation Mechanism Department Representative Patent Attorney Noriyuki Chika (Q) Figure 1 Figure 2 Figure 4

Claims (1)

[Scope of Claims] A vacuum circuit breaker provided in a container filled with insulating gas and having a vacuum valve housed in an insulating cylinder, further comprising an opening in at least a portion of the insulating cylinder facing the upper and lower ends of the vacuum valve. A vacuum circuit breaker characterized by having a section.