JPH01134829A - Gas-blasted circuit breaker - Google Patents

Abstract

PURPOSE:To exhaust hot gas flow well diffused, by providing a fixed electrode with an exhaust hole covering the area from its drum to the side end, and thereby securing a sufficient gas cooling space between the wall surface of a grounding tank and the exhaust hole. CONSTITUTION:When current is shut off, the hot gas 2b after passing an arc passes inside of a fixed contact piece 15 and is exhausted well diffused from an exhaust hole 33 formed in the coverage from the drum 32 of a fixed side electrode 14 to the side end 31, to then be cooled quickly. An insulation support 19 is protected by an electric field shield 14c and the side end, thus being free of risk of being exposed to the hot gas, that should prevent possible deterioration.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a buffer type gas circuit breaker that sprays compressed arc-extinguishing gas onto an arc.

[Prior Art] FIG. 4 is a sectional view showing an isolation chamber of a conventional gas circuit breaker. In Figure 4, the grounded tank (1) is filled with, for example, SF6 gas as an arc-extinguishing gas (2), and the side plates (3) and (4) seal the openings at both ends of the grounded tank (1). are doing. Movable side @ f! i (5) is supported in the ground tank (1) by an insulating support member (not shown) so as not to come into contact with the ground tank (1), and the fixed side electrode (
14) together form a current-carrying path.

A current-carrying contact (6) and a piston (7) are provided at the tip of the movable electrode (5). The movable part (5A) includes a buffer cylinder (8) movably housing a piston (7), a movable contact (9) and an insulating nozzle (10) provided at the tip of the buffer cylinder (8). , a movable arc contactor (11), and a piston rod (12) connected to a rod (13) passing through the side plate (3), and the rod (13) is a drive unit that operates the rod (13). (not shown). Figure 5(a)
and (b) show an enlarged front view and an enlarged side view of the main part of Fig. 4. In Figs. Support member (19
) (19) so as not to come into contact with the inner wall of the grounded tank (1). The fixed side type fft (14) has exhaust ports (14a) on both left and right sides of its body (32), and further has an exhaust port (14a) on the side end (31) perpendicular to the axial direction.
14b). The side end (31) of the fixed side electrode (14)
) is formed around the electric field shield (14c) to protect the insulating support member (19). Furthermore, a fixed contact (15) and a fixed arc contact (16) are provided at the tip of the fixed electrode (14). Furthermore, the fixed side electrode (14) is provided with an adapter (18) connected to a conductor (17) for drawing current to the outside of the grounded tank (1). When shutting off, the compressed arc extinguishing gas (2a) compressed by the piston (7) and buff/r cylinder (8) is
It passes through an insulating nozzle (10) and is blown onto the arc (20) generated between the movable and fixed arc contacts (11) and (16).

The compressed gas (2a) that has passed through the arc (20) becomes hot gas (2b) due to the heat of the arc (20) as shown in Figure 5 (C).
As shown, the air holes (14a) (14b) of the fixed side electrode (14) mainly pass through the inside of the fixed contact (15).
are discharged from the ground tank (1) in a direction perpendicular to the central axis and in the direction of the central axis, respectively.

[Problems to be Solved by the Invention] However, gases subjected to high pressure and high temperature generally have reduced dielectric strength and may even have electrical conductivity. Therefore, it is necessary to discharge the hot gas in a dispersed manner so as not to increase the density polarity of the hot gas flow, and it is also desirable to quickly cool the hot gas. Hot gas
14b) and (14a) are intensively discharged in the direction of the central axis of the grounded tank (1) and in the direction perpendicular to the central axis, and the wall surface of the grounded tank (1) and the fixed side electrode (14) have particularly short insulation distances. Exhaust port (14a) provided in the body (32) of
If the dielectric strength is extremely low between the two and the voltage is high, there is a risk of a ground fault occurring between the two. Therefore, a large-diameter grounded tank must be used to secure the necessary insulation distance and gas cooling space, resulting in the problem that the gas circuit breaker becomes large and the manufacturing cost increases.

This invention was made in order to solve the above-mentioned problems, and there is no need to use a large-sized grounded tank (1), and there is a sufficient space between the wall of the grounded tank (1) and the exhaust port (14a). The gas circuit breaker has excellent withstand voltage performance during current interruption, which secures a gas cooling space, and allows the hot gas flow to be sufficiently dispersed and discharged without being concentrated and blown onto the wall of the grounded tank (1). The purpose is to obtain.

C. Means for Solving Problems] The gas circuit breaker of the present invention includes a grounded tank filled with arc-extinguishing gas, a movable electrode housed in the grounded tank, and a body part that is housed in the grounded tank. A fixed side electrode having a plurality of exhaust ports extending from the side end that does not face the movable side electrode, and a part of the side end of the fixed side electrode where no exhaust port is formed, and connects the fixed side electrode to a grounded tank. It includes an insulating support member that supports the insulating support member so as not to come into contact with the inner surface, and an electric field shield that is divided and formed on the outer periphery of the side end of the stationary side electrode and protects the insulating support member.

[Function] In the gas circuit breaker of the present invention, the hot gas is sufficiently dispersed and discharged from the plurality of exhaust ports formed on the fixed electrode extending from the body to the side end, and the hot gas is discharged from the side of the fixed electrode. An electric field shield formed in segments on the outer periphery of the end portion prevents deterioration of the insulating support member.

[Example] Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of the present invention, and FIGS. 2(a) and 2(b) are a front sectional view and a side sectional view showing essential parts of an embodiment of the invention. be.

The fixed side electrode (14) is an insulating support member (19) (19)
is supported so as not to come into contact with the wall surface of the grounded tank (1). The stationary side mold 1i (14) has exhaust ports (33) on both left and right sides thereof, each having a gentle shape with a chamfered end extending from the body (32) to the side end (31).

Electric field shields (14c) (14c) each having a partially cylindrical shape with a gentle end are formed at the upper and lower parts of the periphery of the side end (31) of the fixed side electrode (14). Two insulating support members (19) that support the fixed side electrode (14)
(19) is the exhaust port (33) (
33) is fixed to the unformed upper and lower parts. This arrangement of the insulating support members (19) (19) is desirable from the viewpoint of mechanical strength for supporting the fixed side electrode (14).

In the above embodiment, when the current is interrupted, the hot gas (2b) passing through the arc will
The fixed side electrode (14) passes through the inside of the fixed contact (15).
The air is discharged in a well-distributed manner through the exhaust ports (33) formed from the body (32) to the side end (31), and is rapidly cooled. Also, the insulation support member (19)
(L9) is the electric field shield (14c) and the side end (31)
Since it is protected by heat gas and is not directly exposed to hot gas, its deterioration is prevented.

FIGS. 3(a) and 3(b) are front and side sectional views showing another embodiment of the present invention. In this embodiment, the insulating support member (19) (19) is made thinner by narrowing the side that is connected to the side end (31) of the stationary electrode (14) within a range that mechanical strength allows, and also as an electric field shield. (14
c) is reduced within a range that can protect the insulating support member (19), and the area of the exhaust port (33) is increased. This further improves the dispersion of the hot gas (2b) and further improves the withstand voltage performance during current interruption.

Although the above embodiment shows a gas circuit breaker having two exhaust ports, the same effect can be obtained even if there are three or more exhaust ports. Regarding insulating support members,
It is also possible to support the fixed side electrode at one location on the side end using one insulating support member, and it is also possible to support it at multiple locations using a plurality of insulating support members. Furthermore, it is also possible to branch one insulating support member and support the fixed electrode at multiple locations on the side end.

[Effects of the Invention] As described above, according to the present invention, by forming an exhaust port extending from the body to the side end of the fixed electrode, the area of the exhaust port is increased, and the insulating support member is protected by an electric field shield. Since it is configured to protect the tank, it improves withstand voltage performance during current interruption without using a large grounding tank.
This has the effect of preventing ilh interference.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an embodiment of the invention, Fig. 2(a)
and FIG. 2(b) are a front sectional view and a side sectional view showing the main parts of a gas circuit breaker according to an embodiment of the present invention, respectively, and FIG. 2(C) is a planar sectional view of the main parts showing the flow of hot gas. 3(a) and 3(b) are respectively a front sectional view and a side sectional view showing essential parts of another embodiment of the present invention, and FIG. 4 is a sectional view showing a conventional gas circuit breaker. , FIG. 5(a) and FIG. 5(b) are respectively a front sectional view and a side sectional view showing the main parts of the gas circuit breaker of FIG. 4, and FIG. 5(C) is a main part showing the flow of hot gas. FIG. As shown in the figure, (14) is the fixed side electrode, (14a) (1
4b) (33) is an exhaust port, (19) is an insulating support member,
(14c) is an electric field shield.

Claims (3)

[Claims] (1) A grounded tank filled with arc-extinguishing gas, a movable electrode housed in the grounded tank, and a side end that is housed in the grounded tank and does not face the movable side electrode from the body. a fixed-side electrode having a plurality of exhaust ports extending across the fixed-side electrode; and an insulating support provided at a side end portion of the fixed-side electrode where no exhaust port is formed, and supporting the fixed-side electrode so as not to come into contact with the inner surface of the grounded tank. A gas circuit breaker, comprising: a member; and an electric field shield that is dividedly formed on the outer periphery of the side end portion of the fixed side electrode and protects the insulating support member. (2) The fixed electrode has two exhaust ports extending from both left and right sides of the body to the side ends, and the insulating support member has an upper and a lower part of the side ends where the exhaust ports are not formed. The fixed side electrode is supported in the grounded tank at two locations, and the electric field shield is provided on the outer periphery of the upper and lower side ends of the fixed side electrode where the insulating support member is provided. The gas circuit breaker according to claim 1, characterized in that: (3) The gas circuit breaker according to claim 1 or 2, wherein the insulating support member is configured to become thinner as the side connected to the fixed electrode approaches the tip.