JPH0629866Y2 - Gas switch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> This invention relates to a gas switch (also used as a concept including a circuit breaker), and more specifically, a movable contact is separated from a fixed contact. The present invention relates to a gas switch that guides an arc generated in some cases to a coil and extinguishes the arc by the action of a magnetic field generated by the coil.

<Prior Art> Conventionally, for the purpose of improving arc extinguishing performance when an electric circuit is opened, a gas excellent in arc extinguishing characteristics such as SF ₆ gas is provided inside an insulating container having a fixed contact and a movable contact. There is provided a switch which encloses.

However, there is a problem in that sufficient arc extinguishing performance cannot be exhibited because the arc and gas are relatively stationary by simply enclosing the gas. In order to further improve the arc extinguishing performance, guide the current that is the source of the arc generated between the movable contact and the fixed contact to the coil and rotate the arc by the action of the magnetic field formed by the coil. It has come to provide the gas switch which was made into.

FIG. 5 is a schematic view showing a conventional example of a gas switch in which an arc is rotated to improve arc extinguishing performance. A fixed contact (32) and a movable contact (33) are provided inside an insulating container (31). ) And a coil (34) and a coil electrode (35) are provided around the fixed contact (32). And, the inside of the insulating container (31) is filled with SF ₆ gas as an arc extinguishing gas.

In the case of the gas switch configured as described above, the movable contactor (33) opens the arc (A) generated between the fixed contactor (32) and the movable contactor (33) during the cutting operation at a predetermined interval. At the time of separation, it is moved between the coil electrode (35) and the movable contactor (33), and the magnetic field is generated by the coil (34), and the magnetic field and the arc are generated.
Using the force acting between (A) (Fleming's left-hand rule) to rotate the arc (A) at high speed, and to blow the arc-extinguishing gas relative to the arc (A). Nigiri
The arc (A) can be extinguished relatively early.

<Problems to be solved by the invention> However, according to the above switch, at the time of the cutting operation,
The gas near the arc expands due to the arc heat and occupies most of the volume of the insulating container. Therefore, until a predetermined time elapses, a gas having a low density (hot gas) at a high temperature directly affected by the arc heat is blown relatively to the arc, which is sufficient for the arc. There was a problem that the cooling effect could not be obtained and the arc extinguishing performance and the insulation recovery characteristics after arc extinguishing were not enough.

<Purpose> The present invention has been made in view of the above problems, and it is possible to rapidly blow cold gas to an arc, and to improve arc extinction performance and insulation recovery characteristics after arc extinction. An object is to provide a gas switch that can be used.

<Means for Solving the Problems> As a gas switch of the present invention for achieving the above object, a first booster chamber enclosing a fixed contact, a movable contact, and a coil inside an insulating container is provided. And a first gas flow passage for guiding the gas in the first pressurizing chamber to the outside is formed inside the movable contactor, and at a predetermined portion of the first pressurizing chamber via a vent hole. A second pressurizing chamber communicating with the pressurizing chamber, a puffer chamber that is thermally separated from the arc, contracts when the second pressurizing chamber pressurizes, and releases the contracted state when depressurizing; The second to guide the gas in the chamber to the arc side
And a gas flow passage of.

<Operation> With the gas switch having the above configuration, during the cutting operation, the arc can be rotated by the coil to blow the arc-extinguishing gas relative to the arc, and at the same time, the arc heat causes It is possible to raise the pressure of the first pressure chamber and also the pressure of the second pressure chamber which is communicated with the first pressure chamber, and the pressure of the second pressure chamber causes the puffer chamber to contract to heat the arc. The cold gas (low temperature and high density) in the puffer chambers that are separated from each other can be pressurized to a predetermined pressure.

When the boosting action of the boosting chamber is reduced near the current zero point, the pressure difference between the first boosting chamber and the outside thereof causes the first boosting chamber to pass outside the boosting chamber through the first gas flow passage. A gas flow can be formed towards the
The gas in the booster chamber can be blown to the arc. When the pressure in the first pressurizing chamber drops due to the generation of the gas flow, the pressure in the second pressurizing chamber follows and drops. At this time, the pressure drop in the second pressurizing chamber can be delayed more than the pressure drop in the first pressurizing chamber due to the throttling action of the vent hole. Therefore, even if the pressure in the first pressurizing chamber drops,
The cold gas in the puffer chamber can be kept under pressure for a predetermined time. This allows the cold gas in the puffer chamber to be blown into the arc through the gas flow passage.

<Examples> Hereinafter, detailed description will be given with reference to the accompanying drawings illustrating examples.

FIG. 1 is a schematic view showing a main part of a gas switch, including a coil (10) having a coil electrode (10a) attached inside an insulating container (11) formed of an insulating material such as synthetic resin, and The fixed contact (12) is provided immovably, and the movable contact (13) is attached by airtightly penetrating the central part of the lower surface plate of the insulating container (11), and further the partition member (14). Thus, the fixed contactor (12), the movable contactor (13), and the coil (10) are surrounded, and the fixed contactor (12) side is used as the first pressurizing chamber (15), and the movable contactor (13) The side is the exhaust chamber (16). And partition member
The movable contactor (13) is introduced into the first pressurizing chamber (15) through the nozzle (n) fixed to the bottom of (14). Further, the movable contactor (13) has an upper portion formed in a tubular shape, and an exhaust port (17a) for gas flow is formed in a lower portion of the tubular portion, whereby the first gas flow passage (17) is formed. ) Is composed. The insulating container (11) is filled with SF ₆ gas as an arc extinguishing gas.

Further, the first pressurizing chamber (15) is provided with a cylindrical partition wall (18a) concentric with the nozzle (n) and surrounding the nozzle (n), and the upper end portion of the partition wall (18a). An annular partition wall (18b) is provided so as to intersect with. The cylindrical partition (18a)
Has a lower end connected to the bottom of the partition member (14) and an upper end airtightly connected to the annular partition (18b). Further, the annular partition wall (18b) is airtightly connected to the partition member (14) at the outer peripheral portion and airtightly connected to the vicinity of the upper end portion of the nozzle (n) at the inner peripheral portion. Has been done. Further, an annular piston (19) that divides the space into upper and lower parts is inserted into the space surrounded by the partition walls (18a) and (18b) and the partition member (14). This piston (1
9) is brought into airtight contact with the partition member (14) and the partition wall (18a) in a vertically slidable manner. The upper side of the piston (19) in the above space is configured as the second pressurizing chamber (20), and the lower side thereof is configured as the puffer chamber (21), and the cylindrical partition wall (18a) and the nozzle (n) are provided. 2) is configured as a second gas flow passage (22).

The second pressure raising chamber (20) communicates with the first pressure raising chamber (15) through a first vent hole (h1) formed in the annular partition wall (18b), and its internal pressure is It is possible to follow the pressure change in the first pressure increasing chamber (15). Further, the puffer chamber (21) communicates with the second gas flow passage (22) via the second ventilation port (h2) formed at the lower end of the cylindrical partition wall (18a). further,
The second gas flow passage (22) communicates with the first pressure raising chamber (15) via a third vent hole (h3) formed near the inner circumference of the partition wall (18b). The respective vent holes (h1) (h2) (h3) are formed at a plurality of locations on the circumference, and the total opening area of the first vent holes (h1) is the third vent hole. It is set to be a predetermined multiple of the total opening area of (h3). Furthermore, the cross-sectional areas of the second pressurizing chamber (20) and the puffer chamber (21) are set to be larger than the cross-sectional area of the second gas flow passage (22). The piston (19) is elastically biased upward by a coil spring (19a). The biasing force of the coil spring (19a) is set within a range in which the piston (19) can be moved downward by the pressure increasing action of the second pressure increasing chamber (20) described later.

With the above configuration, the movable contact (13) is replaced with the fixed contact (12).
First, an arc (A) is generated between the contacts (12) and (13), and the movable contact (13) is further separated from the fixed contact (12) to separate the arc (A). It can be transferred to the coil electrode (10a), the arc (A) is rotated by the magnetic field formed by the coil (10), and the gas in the first pressurizing chamber (15) is directed to the arc (A). Can be sprayed relatively.

At this time, the pressure of the first pressure chamber (15) rises due to the arc heat, so that the pressure of the second pressure chamber is increased through the first vent (h1).
The pressure of (20) rises, and the pressure of the second gas flow passage (22) also rises through the third vent hole (h3). However, the first vent
The sum of the opening areas of (h1) is larger than the sum of the opening areas of the third vent holes (h3), and the pressure in the second pressure chamber (20) is increased before the second gas flow passage (22). To do. As a result, the piston (19)
Can be pushed down by a predetermined distance to pressurize the gas in the puffer chamber (21).

Then, at the time when the current is near the zero point and the boosting action of the first booster chamber (15) is reduced, the first booster chamber (15) and the exhaust chamber (1
A gas flow (23) corresponding to the pressure difference between it and 6) is formed, which allows the gas in the first pressurizing chamber (15) to be blown onto the arc. With the generation of the gas flow (23), the pressure in the first pressurizing chamber (15) drops, and following this pressure drop,
The pressure in the second pressurizing chamber (20) also drops. Therefore, the piston (19) is pushed back upward by the coil spring (19a), and the pressure in the puffer chamber (21) drops. However, due to the throttling action of the first vent hole (h1), the pressure drop in the second pressurizing chamber (20) is delayed compared to the pressure drop in the first pressurizing chamber (15), so the puffer chamber (21) The pressure drop of will also be delayed. That is, the pressure in the puffer chamber (21) can be maintained for a predetermined time even if the pressure in the first pressurizing chamber (15) drops. As a result, the gas in the puffer chamber (21) can be blown to the arc (A) through the second gas flow passage (22). There, the puffer chamber (21) has a partition (18a) and a piston.
The gas in the puffer chamber (21), which is thermally separated from the arc (A) at (19), etc., is cold gas that is not directly affected by the arc heat. (A) can be cooled effectively.

And finally, the piston (19) returns to the original position, the contracted state of the puffer chamber (21) is released, and the hot pressure remaining in the first pressurizing chamber (15), the puffer chamber (21), etc. The gas is replaced with fresh cold gas in the exhaust chamber (16) through the first gas flow passage (17) of the movable contactor (13).

In addition, as the puffer chamber (21), as shown in FIG.
A plurality of independent bellows (24) may be arranged at predetermined intervals, and in this case, a cylindrical partition (18
Since sliding resistance does not occur with respect to a) and the partition member (14), the puffer chamber (21) can be contracted very smoothly. Incidentally, (24a) is a coil spring provided for each bellows (24) in order to release the contracted state.

FIG. 4 is a sectional view showing another embodiment. The basic structure is the same as that of the above-mentioned embodiment, but the movable contactor () is attached to the upper end portion of the second gas flow passage (22). Second in collaboration with 13)
Gas flow passage opening / closing nozzle (25) for opening and closing the gas flow passage (22) of
The feature is that they are connected in series.

The opening / closing nozzle (25) has a short tubular structure with the upper part curved inward, and the inner peripheral part (25a) on the upper end side of the movable contactor (13) is fixed during the cutting operation. Until the contacts (12) are separated by a predetermined distance, they can be brought into airtight and slidable contact with the outer peripheral surface of the movable contact (13).
That is, the inner peripheral portion (25a) of the opening / closing nozzle (25) is located near the upper end of the movable contact (13) in a state where the movable contact (13) is lowered to the open / close end. When the upper end of the movable contactor (13) is located above the inner peripheral portion (25a) of the nozzle (25), the nozzle (2
The movable contactor (13) and the movable contactor (13) can be brought into contact with each other.

With the above configuration, when the movable contact (13) is lowered from the energized state to cut off the electric path, the movable contact (1
Until the 3) passes through the inner peripheral portion (25a) of the nozzle (25), the movable contact (13) and the nozzle (25) cooperate with each other so that the second gas flow passage (22) By closing the upper end portion, it is possible to suppress the hot gas in the first pressurizing chamber (15) from entering the second gas flow passage (22). That is, the gas in the second gas flow passage (22) can be maintained as cold gas. Then, when the movable contactor (13) passes through the inner peripheral portion (25a) of the nozzle (25), the closed state of the second gas flow passage (22) is released, and the second gas flow passage (22 ) And the cold gas of the puffer chamber (21) can be blown onto the arc (A). in this way,
The cold gas in the second gas flow passage (22) can also be blown against the arc (A), so the arc (A)
Can be cooled more effectively. Moreover, since the upper side of the opening / closing nozzle (25) is curved inward, the cold gas can be guided by the curved portion and sprayed directly and efficiently to the arc (A).

In addition, in any of the above examples, the first ventilation port (h
A check valve capable of allowing the flow of gas from the first pressure-increasing chamber (15) to the second pressure-increasing chamber (20) and restricting the flow of gas in the opposite direction to a predetermined amount or less in part (1). May be provided, and in this case, the time delay of the pressure drop in the second pressurizing chamber (20) with respect to the pressure drop in the first pressurizing chamber (15) can be further increased. After the pressure in the first pressure increasing chamber (15) drops, cold gas can be blown for a longer time.

The gas switch of the present invention is not limited to the above-mentioned embodiment. For example, the inside of the insulating container (11) is divided into two parts, the upper part is the pressurizing chamber (15) and the lower part is the exhaust chamber (15). 16), the nozzle (n) is not configured, and the second gas flow passage (2) is provided between the cylindrical partition wall (18a) and the movable contactor (13).
Various design changes can be made within the range not changing the gist of the present invention, such as configuring 2).

<Effect of device> As described above, according to the gas switch of the present invention, the cold gas in the puffer chamber can be quickly blown to the arc, so that the arc extinguishing performance and the insulation recovery characteristics after the arc extinguishing are achieved. Has the unique effect of being able to improve.

[Brief description of drawings]

FIG. 1 is a sectional view showing an energized state of a gas switch according to an embodiment of the present invention, FIG. 2 is a sectional view showing a cutting operation state, and FIGS. 3 and 4 are sectional views showing other embodiments. FIG. 5 is a sectional view showing an example of a conventional gas switch. (10) …… coil, (11) …… insulating container (12) …… fixed contact, (13) …… movable contact (15) …… first booster chamber (16) …… exhaust chamber, ( 17) …… First gas flow passage (19) …… Piston, (20) …… Second pressurization chamber (21) …… Puffer chamber, (22) …… Second gas flow passage (A)… … Arc, (h1) …… Vent

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masayuki Sudo 47 Umezu Takaune-cho, Ukyo-ku, Kyoto City, Nissin Electric Co., Ltd. (56) References: 58-159137

Claims (1)

[Scope of utility model registration request] 1. A gas switch equipped with a fixed contact, a movable contact, and an arc rotating coil inside an insulating container filled with an arc-extinguishing gas, wherein the fixed contact and the movable contact are inside the insulating container. A first booster chamber surrounding the contactor and the coil is provided, and a first gas flow passage for guiding the gas in the first booster chamber to the outside is formed inside the movable contactor. In a predetermined portion of the pressure increasing chamber, a second pressure increasing chamber that is communicated with the pressure increasing chamber through a vent and is thermally separated from the arc, and contracts as the pressure of the second pressure increasing chamber decreases to reduce the pressure. Accordingly, a gas switch which is provided with a puffer chamber whose contracted state is released and a second gas flow passage for guiding the gas in the puffer chamber to the arc side.