JPH0398224A - Gas breaker - Google Patents

Abstract

PURPOSE:To enhance gas blow-out speed and gas arc-extinguish performance by providing a pressure-rise room with a gas passage which leads gas, moved outside by arc revolution, through a space shielded from arc with an annular member to a nozzle side. CONSTITUTION:When a movable contact 23 is set apart from a fixed contact 15, arc A arises between both contacts. The arc is given revolving force by an arc revolving electrode 17 to cause adjacent gas to be also given high-speed revolution and pushed out by centrifugal force. The gas is guided through a gas passage (p) to a nozzle 20 side. The gas ionized due to arc occurrence is fully mixed with fresh gas which is in a space shielding from the arc with an annular member (an arc driving coil 16) while being moved along the gas passage (p), then recovering its arc-extinguish performance. While the movable contact 23 is engaged with the nozzle 20, a pressure-rise room 21 is kept is enclosed condition, so that pressure in the pressure-rise room is allowed sharp rise by strong arc energy.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an arc rotation type gas circuit breaker equipped with a pressurization chamber.

[Prior Art] A gas circuit breaker has been proposed that uses an arc drive coil and a pressurization chamber in combination to improve interrupting performance.

Figures 6 and 7 show the cutoff section of this type of gas circuit breaker that has been proposed in the past. Figure 6 shows the closed state, and Figure 7 shows the main parts in the cutoff state. .

In FIG. 6, 1 and 2 are main circuit conductors on a fixed side and a movable side, respectively, which are arranged facing each other at a predetermined distance and fixed to a circuit breaker container (not shown). A fixed contact 3 is fixed. Reference numeral 4 denotes an arc drive coil provided so as to concentrically surround the fixed contact 1, and one end of which is connected to the conductor 1. An annular arc rotating electrode 5 is connected to the other end of the arc drive coil, and a boosting chamber 6 is provided so as to surround the fixed contact 3, the arc drive coil 4, and the arc rotating electrode 5.

The boosting chamber 6 is provided with an insulating nozzle 6a that shares an axis with the fixed contact. A movable contact 8 is supported on the main circuit conductor 2 via a current collecting contact 7, and this movable contact enters into the boosting chamber 6 through a nozzle 6a and comes into contact with the fixed contact 3.

The above-mentioned interrupting section is housed in a circuit breaker container filled with SF6 gas, and the movable contact 8 is connected to an operating device through an insulated operating rod (not shown).

In the above circuit breaker, in the closed state where the movable contact 8 is in contact with the fixed contact 3, the main circuit conductor ■ - fixed contact 3 - movable contact 8 - current collector contact 7
It flows along the path of one main circuit conductor 2.

When the movable contact 8 separates from the fixed contact 3, an arc A is generated between both contacts, and when the arc moves to the arc rotating electrode 5, an arc current flows through the arc drive coil 4 and the arc drive coil is excited. When the arc drive coil 4 is excited, the magnetic flux generated from the coil interlinks with the arc, causing the arc to rotate at high speed along the arc rotating electrode 5. As a result, SF6 gas is blown relative to the arc, thereby cooling the arc.

Furthermore, the pressure inside the pressurizing chamber 6 increases due to the generation of the arc, but at this time, the gas near the arc R rotates at high speed with the rotation of the arc A, and is moved radially outward as shown by the arrow q due to centrifugal force. Increase the pressure in the space Q inside the pressurization chamber. When the movable contact 8 is separated from the nozzle 6a, the gas in the pressurizing chamber 6 is ejected from the nozzle 6a, and this gas is blown onto the arc A. The arc is extinguished by the synergistic effect of this gas blowing and the cooling effect of the arc due to the relative gas blowing caused by the rotation of the arc.

In the above-mentioned circuit breaker, the gas ionized by the arc is mixed with fresh gas in the space Q outside the arc drive coil and stirred to reduce the amount of gas blown onto the arc when the movable contact leaves the nozzle. It is intended to ensure arc-extinguishing performance.

[Problems to be Solved by the Invention] In the above-mentioned circuit breaker, since the upper end of the space Q outside the arc drive coil was closed, there was a problem that the ionized gas and the fresh gas in the space Q could not be sufficiently stirred. there were. Furthermore, the gas in the vicinity of the arc flows out of the nozzle 6a against the inertia of blowing in the direction of arrow q at the moment the movable contact passes through the nozzle 6a, so it is not possible to increase the gas blowing speed that much. Therefore, there was a problem in that it was difficult to spray gas effectively against the arc.

An object of the present invention is to improve the stirring of gas ionized by the generation of an arc and fresh gas, and to
To provide a gas circuit breaker capable of effectively blowing gas at the moment a movable contact leaves a nozzle.

[Means for Solving the Problems] The present invention comprises a fixed contact, a movable contact, an arc drive coil whose one end is electrically connected to the fixed contact, and an arc rotating electrode connected to the other end of the arc drive coil. a pressurizing chamber that is provided so as to surround an arc generation space and has a nozzle at one end that allows the movable contact to pass through, and the contact is arranged at a closing position where it contacts a fixed contact and a position where it is separated from the fixed contact and removed from the nozzle. This relates to a gas circuit breaker that can be displaced between a cutoff position and a cutoff position.

In order to achieve the above object, in the present invention, a gas flow path is provided in the pressurizing chamber to guide the gas moved outward by the rotation of the arc to the nozzle side through a space substantially shielded from the arc by an annular member. Ta.

The annular member is, for example, an arc drive coil, and in this case, the gas flow path includes a space outside the arc drive coil, a space between the other end of the arc drive coil and the inner surface of the boosting chamber, and a gas flow path between the space outside the arc drive coil and the space between the other end of the arc drive coil and the inner surface of the pressurization chamber. It is shaped so as to guide gas to the nozzle side through the inner space.

Furthermore, an annular member sharing an axis with the arc rotating electrode is particularly provided between the arc rotating electrode and the nozzle, and gas is supplied from the space between the arc rotating electrode and the annular member to the nozzle side through the space outside the annular member. The gas flow path can also be shaped to lead.

In this case, since the outer diameter of the annular member is set smaller than the outer diameter of the arc drive coil, the outer diameter of the pressurizing chamber can be made smaller.

[Function] As described above, if a gas flow path is provided in the pressurization chamber that guides the gas moved outward by the rotation of the arc to the nozzle side through the space shielded from the arc by the annular member, the movable contact will move away from the nozzle. At the moment of separation, the gas that has moved toward the nozzle through the gas flow path is jetted out in the same direction, so the gas jetting speed can be increased and the gas can be effectively sprayed against the arc.

It is also ionized by the generation of an arc. While moving through the gas flow path, the gas is mixed and stirred with fresh gas in the space shielded from the arc, so the moment the movable contact leaves the nozzle, the gas whose arc-extinguishing performance has been restored is transferred to the arc. In addition to being able to increase the gas blowing speed to the arc, the interrupting performance can be improved.

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

Figures 1 to 3 show the interrupting part of the gas circuit breaker according to the embodiment of the present invention, with Figure 1 showing the closed state and Figure 2 showing a sectional view taken along the line nn in Figure 1. ing. Moreover, FIG. 3 shows the cut-off state.

In FIGS. 1 and 2, 11 and 12 are a fixed side main circuit conductor and a movable side main circuit conductor, respectively, which are arranged facing each other at a predetermined distance and fixed to a circuit breaker container (not shown). . External terminals (not shown) are connected to both conductors.

The main circuit conductor 11 is formed in the shape of an upside-down cup, and conductive support ribs 1 are provided at intervals in the circumferential direction on the inner surface of the ceiling portion of the main circuit conductor, as shown in FIG.
An annular conductor 14 is connected via 3. Annular conductor 1
A cylindrical fixed contact 15 is fixed to 4, and a contact portion 15a is provided at the tip of the fixed contact 15. An arc drive coil 16 is provided so as to concentrically surround the fixed contact 1, and one end of this coil is connected to the annular conductor 14. At the other end of the arc drive coil is an annular arc rotating electrode 1.
7 is connected.

The upper end of an insulating cylinder 18 is connected to the lower end of the main circuit conductor 11, and the bottom plate 19 is connected to the lower end of the insulating cylinder 18. An insulating nozzle 20 that shares an axis with the fixed contact 15 is provided at the center of the bottom plate 19, and is connected to the main circuit conductor 11 and the insulating tube 1.
8 and a bottom plate 19 provided with a nozzle 20 constitute a pressurizing chamber 21.

A gas guide member 22 that shares an axis with the fixed contact 15 is attached to the center of the inner surface of the ceiling portion of the main circuit conductor 11 . This gas guide member 22 is made of a conical body that is convex toward the annular conductor 14 side, and has a gas guide surface 22a having a smooth curved longitudinal section on its outer periphery.

Reference numeral 23 denotes a movable contact formed in the shape of a rod. The movable contact q 10 is supported by penetrating the main circuit conductor 12, and is in the closing position where it contacts the fixed contact 15 from the inside through the nozzle 20, as shown in FIG. and a blocking position where the contact 15 is separated from the nozzle 20 as shown in FIG.

A current collecting contact 24 that makes sliding contact with the movable contact 23 is attached to the main circuit conductor 12, and the movable contact 23 is electrically connected to the main circuit conductor 12 via the current collecting contact 24.

The above-mentioned interrupting section is housed in a circuit breaker container filled with SF6 gas, and the movable contact 23 is connected to an operating device through an insulated operating rod (not shown).

In the above embodiment, the drive coil 16 is used as an annular member that shields the space constituting the gas flow path from the arc, and as shown by the arrow p in FIGS. Space S outside the drive coil → Space T between the annular conductor 14 and main circuit conductor 11 → Space U inside the arc drive coil 16 → Gas that guides gas near the arc to the nozzle 20 along the path of the nozzle 20 A flow path is configured.

When the above-mentioned gas circuit breaker is in the closed state shown in FIG.
A main circuit current flows through the path of 4-main circuit conductor 12. When the movable contact 23 is driven upward and downward in the drawing and moves away from the fixed contact, an arc A is generated between both contacts. When this arc contacts the arc rotating electrode 17, an arc current flows through the arc drive coil 16.
The magnetic flux generated from the coil interlinks with the arc A. This gives a rotational force to the arc, causing the arc to rotate at high speed along the arc rotating electrode 17. As the arc rotates, gas in the vicinity also rotates at high speed and is pushed outward in the radial direction by centrifugal force. This gas is guided to the nozzle 20 side through the gas flow path p. While the gas ionized by the generation of the arc moves along the gas flow path p, it is sufficiently mixed and stirred by the annular member (arc drive coil 16 in this example) with fresh gas in the space shielded from the arc. The arc-extinguishing performance is restored. While the movable contact 23 is fitted to the nozzle 20, the pressurization chamber 2
1 is in a substantially hermetically sealed state, the pressure within the pressurization chamber is rapidly increased by the intense energy of the arc.

When the movable contact 23 separates from the nozzle 20, the pressurizing chamber 21 is opened through the nozzle 20, so that the pressurizing chamber 2
A gas flow exits from 1 to the outside through a nozzle 20 . When the nozzle 20 is opened, the gas that has flowed to the nozzle 20 side through the gas flow path directly flows through the nozzle 2.
Since the gas flows out from the nozzle 20, the flow rate of the gas flowing out from the nozzle 20 can be made sufficiently high. Therefore, at the moment when the movable contact 23 leaves the nozzle 20, a large amount of gas whose arc-extinguishing performance has been restored by mixing with fresh gas can be sprayed onto the arc A at once, and the arc can be surely extinguished at the current zero point. I can do it.

In the above embodiment, the arc drive coil 16 was provided as an annular member that shielded the space constituting the gas flow path for flowing the gas moved outward by the rotation of the arc from the arc. A special annular member may be provided to shield the space constituting the space from arcs.

4 and 5 show another embodiment of the present invention, in which the main circuit conductor 11' is shaped like a flat plate, and the fixed contact 15 and the arc drive coil are connected to the main circuit conductor 11'. One end of 16 is directly connected. A first arc rotating electrode 17 is connected to the other end of the arc drive coil l6.

Further, in this example, the upper end of the insulating tube l8- is hermetically connected to the main circuit conductor 11', and a booster chamber 2 is placed inside the insulating tube 18'.
l is constructed. An insulating nozzle 20 is provided at the bottom of the insulating tube.

An annular member 25 is provided in a space between the arc rotating electrode 17 and the nozzle 20 so as to share an axis with the arc rotating electrode. The annular member 25 includes an annular body 25a made of an insulating material and a second arc rotation 13 17i electrode 25b provided so as to cover the outer surface of the annular body 25a. The second arc rotating electrode 25b is an annular conductive plate 25 connected back to both ends of the annular body 25a.
bl, 25b2, and a conductive cylinder 25b3 provided so as to cover the inner periphery of the annular body, and the annular body 25a covers the inner periphery of the insulating cylinder 18' by a plurality of insulating support arms 26 provided radially. is supported by

The arc rotating electrodes 17 and 25b are made of arc-resistant material such as Cu--W sintered alloy or graphite.

Further, the space between the first arc rotating electrode 17 provided on the arc drive coil side and the annular member 25, the space outside the annular member 25, and the space between the annular member 25 and the nozzle 20, A gas flow path p is configured to guide nearby gas to the nozzle 20 side.

In the embodiment shown in FIGS. 4 and 5, after the movable contact 23 is separated from the fixed contact 15, the tip of the movable contact is connected to the conductive plate 25 of the second arc rotating electrode 25b.
Until the position b1 is reached, an arc is generated between the tip of the movable contact 23 and the arc rotating electrode 17, and the arc rotates at high speed along the arc rotating electrode 17. When the tip of the movable contact 23 reaches the position of the conductive plate 25b1, the arc comes into contact with the second arc rotating electrode 25b, and when the tip of the movable contact 23 moves closer to the nozzle than the conductive plate 25b2, the first arc Arcs A1 and A2 are generated between the rotating plate 17 and the second arc rotating plate 25b and between the second arc rotating electrode 25b and the movable contact 23, respectively. These arcs rotate at high speed along arc rotating electrodes 17 and 25b.

The gas moved radially outward by the rotation of the arc generated between the movable contact 23 and the arc rotating electrode 17 is guided to the nozzle side through the gas flow path p.

When the movable contact 23 separates from the nozzle 20, the gas in the boosting chamber 21 flows out of the nozzle 20 all at once, and this gas is sprayed onto the arc, so that the arc is extinguished at the current zero point.

In the circuit breaker to which the present invention is directed, since the arc drive coil 16 receives a large electromagnetic mechanical force, it is necessary to make its mechanical strength sufficiently high. Therefore, it is inevitable that the diameter of the arc drive coil 16 increases to some extent. Therefore, when the gas flow path p is formed around the arc drive coil 16 as in the embodiment shown in FIGS. 1 to 3, it is possible to avoid increasing the diameter of the insulating tube 18. do not have.

On the other hand, as shown in FIGS. 4 and 5, if an annular member 25 is particularly provided between the arc drive coil 16 and the nozzle 20 and the gas flow path is formed by this annular member, the annular The member 25 is simply for ensuring a gas flow path, and does not need to be constructed in a large size to ensure strength like the arc drive coil 16, so the outer part of this annular member 25 is The diameter can be set smaller than the outer diameter of the arc drive coil 16. Therefore, the insulation tube↑
The gas flow path p can be formed without increasing the outer diameter of 8'.

The smaller the diameter of the insulating tube 18', the easier it is to ensure its strength. Accordingly, according to the embodiments shown in FIGS. 4 and 5, the insulating tube 18' can withstand the pressure increase when an arc occurs. can be easily obtained.

[Effects of the Invention] As described above, according to the present invention, a gas flow path is provided in the pressurizing chamber to guide the gas moved outward by the rotation of the arc to the nozzle side through the space shielded from the arc by the annular member. Therefore, the moment the movable contact leaves the nozzle, the gas that has moved toward the nozzle through the gas flow path can be jetted out in the same direction, thereby increasing the gas jetting speed.

In addition, the gas ionized by the arc is mixed and stirred with fresh gas in the space shielded from the arc while moving through the gas flow path, so the arc extinguishing performance is achieved the moment the movable contact leaves the nozzle. The recovered gas can be effectively blown onto the arc, and together with the ability to increase the speed at which the gas is blown onto the arc, there is an advantage that the interrupting performance can be improved.

In particular, according to the third aspect of the invention, an annular member having an outer diameter smaller than the arc drive coil is disposed between the arc drive coil and the nozzle, and a gas flow path is formed outside the annular member. This has the advantage that the outer diameter of the pressurization chamber can be reduced, and a pressurization chamber that can withstand the pressure increase when an arc occurs can be easily designed.

[Brief explanation of drawings]

1 to 3 show embodiments of the present invention,
Figure 1 is a vertical sectional view of the main part in the loaded state, Figure 2 is the n of Figure 1.
-n line cross-sectional view, Figure 3 is a vertical cross-sectional view of the main part in the cut-off state, Figure 4
5 and 5 are longitudinal cross-sectional views of main parts showing the closing and closing states of other embodiments of the present invention, respectively, and FIGS. 6 and 7 show the closing and closing states of a conventional circuit breaker, respectively. It is a longitudinal cross-sectional view of the main part. 11.11-. 12... Main circuit conductor, 15... Fixed contact, 16... Arc drive coil, 17...
Arc rotating electrode, 18.18-...Insulating cylinder, 19...
- Insulating plate, 20... Insulating nozzle, 21... Boosting chamber,
23... Movable contact, 25... Annular member, 25
b...Arc rotating electrode. 19 20 Fig. 4 Fig. 6 Fig. 5 Fig. 7

Claims (3)

[Claims] (1) A fixed contact, a movable contact, an arc drive coil whose one end is electrically connected to the fixed contact, an arc rotating electrode connected to the other end of the arc drive coil, and an arc generating space surrounding the arc generating space. a pressurizing chamber provided at one end with a nozzle for penetrating the movable contact; a closing position in which the movable contact contacts the fixed contact through the nozzle; and a blocking position in which the movable contact is separated from the fixed contact and detached from the nozzle. In the gas circuit breaker, the gas moved radially outward by the rotation of the arc is passed through a space substantially shielded from the arc by an annular member to the nozzle. A gas circuit breaker, characterized in that a gas flow path leading to the side is provided in the pressure boosting chamber. (2) The annular member is the arc drive coil,
The gas flow path guides gas to the nozzle side through a space outside the arc drive coil, a space between the other end of the arc drive coil and an inner surface of the boosting chamber, and a space inside the arc drive coil. The gas circuit breaker according to claim 1, wherein the gas circuit breaker is formed as follows. (3) The annular member is provided in a space between the arc rotating electrode and the nozzle so as to share an axis with the arc rotating electrode, and the outer diameter of the annular member is larger than the outer diameter of the arc drive coil. is also set small, and the gas flow path is formed to guide gas from the space between the arc rotating electrode and the annular member to the nozzle side through the space outside the annular member. The gas circuit breaker according to claim 1.