JP2004103318A

JP2004103318A - Circuit breaker

Info

Publication number: JP2004103318A
Application number: JP2002261350A
Authority: JP
Inventors: Kazuhiro Matsuo; 松尾　和宏; Kosei Wakabayashi; 若林　孝生; Mitsutaka Honma; 本間　三孝; Hiroki Kagara; 加々良　弘樹
Original assignee: Toshiba Corp
Current assignee: Toshiba Corp
Priority date: 2002-09-06
Filing date: 2002-09-06
Publication date: 2004-04-02

Abstract

<P>PROBLEM TO BE SOLVED: To provide a circuit breaker with high reliability for frequent opening/closing without a bounce of a movable shaft in the progress of current breaking and without an occurrence of an insulation break phenomenon at a breaking part. <P>SOLUTION: The circuit breaker includes an operation shaft 16 of which one end is coupled loosely with a movable shaft 15 derived from a breaking part 1; a closed circuit state holding means 11 provided at the other end of the operation shaft 16 to hold a closing state of the breaking part 1; and an opened circuit operation means (3, 4) provided at the operation shaft 16 to drive the operation shaft 16 in a breaking direction by using electromagnetic repulsion. <P>COPYRIGHT: (C)2004,JPO

Description

【０００１】
【発明の属する技術分野】
本発明は、真空バルブ等の電気接点を有する遮断部を操作軸により開閉操作する遮断器に関する。
【０００２】
【従来の技術】
真空バルブ等の電気接点を有する遮断部を操作軸によって開閉操作する従来の遮断器は図３に示すようになっている。すなわち、真空バルブ１の可動軸１ａにはサポート２が取り付けられており、サポート２の上側にはドーナツ状銅板３が取り付けられている。ドーナツ状銅板３は、固定フレーム５に取り付けられたコイル４とある間隙を介して対向している。サポート２とロッド６はロッド６に取り付けられサポート２の長穴２ａを通るピン７にて連結されており、サポート２はばね８によって押し上げられている。
【０００３】
遮断器の投入時においてロッド６は真空バルブ１の接点が接触後もある程度投入方向に移動可能であり、真空バルブ１の接点の接触後は、ばね８により接点に接触圧力が与えられている。各相に設けられているロッド６は連結バー９により結合され、連結バー９は電磁アクチュエータ１１の操作軸１０に結合されている。
【０００４】
例えば、特開２００２−８４９８号公報に示されているように、遮断器投入後の投入状態の保持は、電磁アクチュエータ１１の内側に配置した永久磁石１２と磁性体１２ａの間の吸引力により行う。
【０００５】
遮断動作は次のように行われる。すなわち、コイル４に接続したコンデンサ１３には電荷が充電されており、遮断動作時にはサイリスタスイッチ１４を導通させることによりコイル４に電流を通電させる。この通電電流の電磁誘導作用によりドーナツ状銅板３にはコイル４と逆方向に電流が流れる。これによって、コイル４とドーナツ状銅板３には電磁反発力が発生しサポート２は下方向に力を受け、サポート２に結合された可動軸１ａは下方へ駆動されて真空バルブ１内の接点が解離される。同時に、下方向に力を受けたサポート２の長穴２ａの端部がピン７と衝突することにより、ロッド６、連結バー９および操作軸１０を介して永久磁石１２と磁性体１２ａの吸着が解除される。
【０００６】
【発明が解決しようとする課題】
上述した従来の遮断器においては、開路途中でのサポート２とピン７の衝突によって可動軸１ａが跳ね返り、真空バルブ１内の接点が必要間隙以下となり、電流遮断途中における絶縁破壊現象が発生し、信頼性に欠けるという問題がある。
【０００７】
この点を、分かりやすいように図４の単相簡易モデルによって説明すると以下のようになる。すなわち、まずコイル４による電磁反発力Ｆ１によってサポート２および可動軸１ａ（斜線部）は下向きに駆動される。サポート２および可動軸１ａは瞬時に動作するが、途中でピン７と衝突する。この衝突はロッド６と操作軸１０を経て磁性体１２ａに伝えられ、永久磁石１２と磁性体１２ａの間の磁気吸引力Ｆ２にうちかって両者を引き離す。これによって操作軸１０は開路方向へと動作する。しかしながら、サポート２および可動軸１ａは前記衝突により一時開路とは反対方向へ跳ね返る。
【０００８】
このとき電磁反発力Ｆ１はコンデンサ１３による瞬時エネルギであるため、すでに消滅している。また、この時間までコンデンサ１３の放電があったとしても電磁反発力を発生させるコイル４とドーナツ状銅板３の間のギャップは大きくなっており（開路方向へ移動しているため）電磁反発力Ｆ１は小さな値となる。従って、可動軸１ａのストロークは図４（ｂ）に示すように振動する。
【０００９】
また従来の遮断器においては、コイル４の抵抗値のばらつきにより、開路時発生させる電磁反発力に各相のばらつきが生じ、垂直方向動作のずれが発生し、操作軸１０と電磁アクチュエータ１１の軸受部との摩擦により、多頻度開閉したとき軸受部が摩耗するばかりでなく、開路時の力のロスが発生し開路に至らないこともあるという信頼性に欠ける問題がある。
【００１０】
そこで本発明は、電流遮断途中における可動軸のはね返りが無く、遮断部において絶縁破壊現象が発生せず、多頻度の開閉に対する信頼性の高い遮断器を提供することを目的とする。
【００１１】
【課題を解決するための手段】
請求項１の発明は、遮断部から引き出された可動軸に一端を遊びをもって結合された操作軸と、前記操作軸の他端に設けられ前記遮断部の閉路状態を保持する閉路状態保持手段と、前記操作軸に設けられ電磁反発作用を利用して前記操作軸を遮断方向へ駆動する開路操作手段とを備えた構成とする。
【００１２】
本発明によれば、電流遮断途中における可動軸のはね返りが無く、遮断部において絶縁破壊現象が発生せず、多頻度の開閉に対する信頼性の高い遮断器を提供することができる。
【００１３】
請求項２の発明は、請求項１の発明において、複数の遮断部に対して単一の開路操作手段および単一の閉路状態保持手段を備えた構成とする。
本発明によれば、電流遮断途中における可動軸のはね返りが無く、遮断部において絶縁破壊現象が発生せず、多頻度の開閉に対する信頼性の高い多相の遮断器を提供することができる。
【００１４】
【発明の実施の形態】
本発明の実施の形態の遮断器を図１，図２を参照して説明する。
図１（ａ）に示すように、３相に設けられているロッド６は連結バー９に結合され、連結バー９は、閉路状態保持手段である電磁アクチュエータ１１の操作軸１６に結合され、一体として上下動作を行う。操作軸１６にはサポート１７が結合されており、サポート１７の上側にはドーナツ状銅板３が、フレーム５に取り付けられたコイル４とある間隙を存して対向して取り付けられている。ドーナツ状銅板３とコイル４は開路操作手段を構成する。遮断器投入後の投入状態の保持は、電磁アクチュエータ１１の内側に配置した永久磁石１２と磁性体１２ａの間の吸引力により行う。
【００１５】
図１（ｂ）に示すように、ロッド６に取り付けられたピン７は、遮断部である真空バルブ１の可動軸１５に形成された長穴１５ａに挿通されており、遮断器の投入時においてロッド６は、真空バルブ接点が接触後もある程度投入方向に動作可能である。従って、接点接触後は、ばね８により接触加圧力が接点に与えられている。
【００１６】
遮断動作は次のように行われる。すなわち、コイル４に接続したコンデンサ１３には電荷が充電されており、遮断動作時にはサイリスタスイッチ１４を導通させることによりコイル４に電流を通電させる。この通電電流の電磁誘導作用によりドーナツ状銅板３にはコイル４と逆方向に電流が流れる。これによって、コイル４とドーナツ状銅板３の間には図２（ａ）に示すように電磁反発力Ｆ１が発生し、サポート１７は下方向に力Ｆ１を受ける。この力Ｆ１は操作軸１６を経て磁性体１２ａに伝わり、永久磁石１２と磁性体１２ａの間の磁気吸引力Ｆ２にうちかって両者を解離する。この解離によって操作軸１６、連結バー９およびロッド６は下方向に駆動される。そして、ロッド６に取り付けられたピン７が可動軸１５の長穴１５ａと衝突することで可動軸１５は開路動作を行う。このとき、可動軸１５のストロークの経時変化は図２（ｂ）のようになり、可動軸１５ははね返りを生じない。
【００１７】
本実施の形態の遮断器においては、ピン７と長穴１５ａの衝突後も可動軸１５の投入方向へのはね返りがなく、遮断途中での絶縁破壊が発生しない。
また、本実施の形態の遮断器においては、操作軸１６に垂直方向に力を伝達することができ、アクチュエータ１１の軸受け部の摩耗を抑制し、かつ開路時の力のロスが無くなり、信頼性を向上させることができる。
【００１８】
なお、本発明は上記実施の形態のみに限定されず、例えば、３相に限らず、２相、単相で構成される形態においても可動軸１５の跳ね返りを無くすことができかつ操作軸１６は垂直方向のみに力を与えられることができる。
【００１９】
また、上記実施の形態のような永久磁石１２により投入保持を行なう場合のみならず、いかなる投入保持形態においても可動軸１５の跳ね返りを無くすことができかつ操作軸は垂直方向のみに力を与えられることができる。さらに、遮断部は真空バルブ１の代りに気中や油中の遮断部であってもよい。また、ロッド６と操作軸１６は同じものであってもよい。
【００２０】
【発明の効果】
本発明によれば、電流遮断途中における可動軸のはね返りが無く、遮断部において絶縁破壊現象が発生せず、多頻度の開閉に対する信頼性の高い遮断器を提供することができる。
【図面の簡単な説明】
【図１】本発明の実施の形態に係る遮断器を示し、（ａ）は全体の正面図、（ｂ）は（ａ）の要部側面図。
【図２】本発明の実施の形態に係る遮断器の作用を説明し、（ａ）は単相簡易モデル図、（ｂ）は可動軸のストロークを示す曲線図。
【図３】従来の遮断器を示し、（ａ）は全体の正面図、（ｂ）は（ａ）の要部側面図。
【図４】従来の遮断器の作用を説明し、（ａ）は単相簡易モデル図、（ｂ）は可動軸のストロークを示す曲線図。
【符号の説明】
１…真空バルブ、１ａ…可動軸、２…サポート、２ａ…長穴、３…ドーナツ状銅板、４…コイル、５…フレーム、６…ロッド、７…ピン、８…ばね、９…連結バー、１０…操作軸、１１…電磁アクチュエータ、１２…永久磁石、１２ａ…磁性体、１３…コンデンサ、１４…サイリスタスイッチ、１５…可動軸、１５ａ…長穴、１６…操作軸、１７…サポート、Ｆ１…電磁反発力、Ｆ２…磁気吸引力。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a circuit breaker that opens and closes a breaking unit having an electrical contact such as a vacuum valve with an operating shaft.
[0002]
[Prior art]
FIG. 3 shows a conventional circuit breaker in which a breaking unit having an electric contact such as a vacuum valve is opened and closed by an operating shaft. That is, the support 2 is attached to the movable shaft 1 a of the vacuum valve 1, and the donut-shaped copper plate 3 is attached above the support 2. The donut-shaped copper plate 3 is opposed to the coil 4 attached to the fixed frame 5 via a certain gap. The support 2 and the rod 6 are connected to each other by a pin 7 attached to the rod 6 and passing through the elongated hole 2 a of the support 2, and the support 2 is pushed up by a spring 8.
[0003]
When the circuit breaker is closed, the rod 6 can be moved to some extent in the closing direction even after the contact of the vacuum valve 1 contacts, and after the contact of the contact of the vacuum valve 1, a contact pressure is applied to the contact by a spring 8. The rods 6 provided in each phase are connected by a connecting bar 9, and the connecting bar 9 is connected to an operation shaft 10 of an electromagnetic actuator 11.
[0004]
For example, as shown in Japanese Patent Application Laid-Open No. 2002-8498, the closing state after the closing of the circuit breaker is maintained by the attractive force between the permanent magnet 12 disposed inside the electromagnetic actuator 11 and the magnetic body 12a. .
[0005]
The shut-off operation is performed as follows. That is, the capacitor 13 connected to the coil 4 is charged with electric charge, and the electric current is supplied to the coil 4 by turning on the thyristor switch 14 during the cutoff operation. The current flows in the donut-shaped copper plate 3 in the opposite direction to the coil 4 due to the electromagnetic induction of the current. As a result, an electromagnetic repulsive force is generated in the coil 4 and the donut-shaped copper plate 3, and the support 2 receives a downward force, and the movable shaft 1a coupled to the support 2 is driven downward, so that the contacts in the vacuum valve 1 are closed. Dissociated. At the same time, the end of the elongated hole 2a of the support 2 which has received a downward force collides with the pin 7, so that the permanent magnet 12 and the magnetic body 12a are attracted via the rod 6, the connecting bar 9 and the operating shaft 10. It is released.
[0006]
[Problems to be solved by the invention]
In the above-described conventional circuit breaker, the movable shaft 1a rebounds due to the collision between the support 2 and the pin 7 during the opening, the contact in the vacuum valve 1 becomes smaller than the required gap, and a dielectric breakdown phenomenon occurs during the current interruption. There is a problem of lack of reliability.
[0007]
This point will be described below with reference to the single-phase simplified model of FIG. 4 for easy understanding. That is, first, the support 2 and the movable shaft 1a (shaded portion) are driven downward by the electromagnetic repulsion force F1 by the coil 4. The support 2 and the movable shaft 1a operate instantaneously, but collide with the pin 7 on the way. This collision is transmitted to the magnetic body 12a via the rod 6 and the operation shaft 10, and separates them by the magnetic attraction F2 between the permanent magnet 12 and the magnetic body 12a. As a result, the operation shaft 10 moves in the opening direction. However, the support 2 and the movable shaft 1a rebound in the direction opposite to the temporary opening due to the collision.
[0008]
At this time, since the electromagnetic repulsion F1 is instantaneous energy by the capacitor 13, it has already disappeared. Further, even if the capacitor 13 is discharged until this time, the gap between the coil 4 and the donut-shaped copper plate 3 that generate the electromagnetic repulsion is large (because it moves in the opening direction), and the electromagnetic repulsion F1 is generated. Is a small value. Therefore, the stroke of the movable shaft 1a vibrates as shown in FIG.
[0009]
Further, in the conventional circuit breaker, variations in the resistance value of the coil 4 cause variations in each phase in the electromagnetic repulsive force generated at the time of opening, causing a shift in the vertical operation, and a bearing between the operating shaft 10 and the electromagnetic actuator 11. Due to friction with the parts, not only does the bearing part wear out when it is frequently opened and closed, but also there is a problem of lack of reliability that a loss of force at the time of opening occurs and the circuit may not be opened.
[0010]
SUMMARY OF THE INVENTION It is an object of the present invention to provide a circuit breaker that has no rebound of a movable shaft during current interruption, does not cause an insulation breakdown phenomenon in an interruption part, and has high reliability for frequent switching.
[0011]
[Means for Solving the Problems]
The invention according to claim 1 is an operation shaft, one end of which is coupled with play to a movable shaft pulled out from a blocking portion, and closed state holding means provided at the other end of the operation shaft for holding a closed state of the blocking portion. And an open-circuit operating means provided on the operating shaft for driving the operating shaft in a blocking direction by utilizing an electromagnetic repulsion.
[0012]
According to the present invention, it is possible to provide a circuit breaker that has no rebound of the movable shaft during current interruption, does not cause an insulation breakdown phenomenon in the interruption section, and has high reliability for frequent switching.
[0013]
According to a second aspect of the present invention, in the first aspect of the present invention, a single opening operation means and a single closed state holding means are provided for the plurality of blocking portions.
According to the present invention, it is possible to provide a multi-phase circuit breaker that has no rebound of the movable shaft during current interruption, does not cause an insulation breakdown phenomenon in the interruption section, and has high reliability for frequent opening and closing.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
A circuit breaker according to an embodiment of the present invention will be described with reference to FIGS.
As shown in FIG. 1A, the rods 6 provided in three phases are connected to a connecting bar 9, and the connecting bar 9 is connected to an operating shaft 16 of an electromagnetic actuator 11 as a closed state holding means, and is integrally formed. Up and down operation. A support 17 is connected to the operation shaft 16, and a donut-shaped copper plate 3 is mounted above the support 17 so as to face the coil 4 mounted on the frame 5 with a certain gap. The donut-shaped copper plate 3 and the coil 4 constitute an opening operation means. After the circuit breaker is closed, the closed state is maintained by the attractive force between the permanent magnet 12 disposed inside the electromagnetic actuator 11 and the magnetic body 12a.
[0015]
As shown in FIG. 1 (b), the pin 7 attached to the rod 6 is inserted into a long hole 15a formed in the movable shaft 15 of the vacuum valve 1 which is a breaking part, and when the breaker is turned on. The rod 6 is operable to some extent in the closing direction even after the vacuum valve contact comes into contact. Therefore, after the contact of the contact, the contact pressure is applied to the contact by the spring 8.
[0016]
The shut-off operation is performed as follows. That is, the capacitor 13 connected to the coil 4 is charged with electric charge, and the electric current is supplied to the coil 4 by turning on the thyristor switch 14 during the cutoff operation. The current flows in the donut-shaped copper plate 3 in the opposite direction to the coil 4 due to the electromagnetic induction of the current. As a result, an electromagnetic repulsion force F1 is generated between the coil 4 and the donut-shaped copper plate 3, as shown in FIG. 2A, and the support 17 receives the force F1 in the downward direction. This force F1 is transmitted to the magnetic body 12a via the operation shaft 16, and dissociates the permanent magnet 12 and the magnetic body 12a due to the magnetic attraction force F2. By this disengagement, the operation shaft 16, the connecting bar 9 and the rod 6 are driven downward. When the pin 7 attached to the rod 6 collides with the elongated hole 15a of the movable shaft 15, the movable shaft 15 performs an opening operation. At this time, the change over time of the stroke of the movable shaft 15 is as shown in FIG. 2B, and the movable shaft 15 does not rebound.
[0017]
In the circuit breaker according to the present embodiment, the movable shaft 15 does not rebound in the closing direction even after the collision between the pin 7 and the elongated hole 15a, and no dielectric breakdown occurs during the interruption.
Further, in the circuit breaker according to the present embodiment, the force can be transmitted in the vertical direction to the operation shaft 16, the wear of the bearing portion of the actuator 11 can be suppressed, and the loss of force at the time of opening the circuit is eliminated, and the reliability is improved. Can be improved.
[0018]
Note that the present invention is not limited to the above-described embodiment. For example, the movable shaft 15 can be prevented from rebounding even in a form of not only three phases but also two phases and a single phase. The force can be applied only in the vertical direction.
[0019]
In addition, not only when the closing and holding is performed by the permanent magnet 12 as in the above-described embodiment, but also in any closing and holding mode, the rebound of the movable shaft 15 can be eliminated and the operation shaft can be given a force only in the vertical direction. be able to. Further, the shutoff unit may be an air or oil shutoff unit instead of the vacuum valve 1. Further, the rod 6 and the operation shaft 16 may be the same.
[0020]
【The invention's effect】
According to the present invention, it is possible to provide a circuit breaker that has no rebound of the movable shaft during current interruption, does not cause an insulation breakdown phenomenon in the interruption section, and has high reliability for frequent switching.
[Brief description of the drawings]
1A and 1B show a circuit breaker according to an embodiment of the present invention, wherein FIG. 1A is a front view of the entire circuit, and FIG. 1B is a side view of a main part of FIG.
FIGS. 2A and 2B illustrate the operation of the circuit breaker according to the embodiment of the present invention, in which FIG. 2A is a single-phase simplified model diagram, and FIG. 2B is a curve diagram showing a stroke of a movable shaft.
3A and 3B show a conventional circuit breaker, wherein FIG. 3A is a front view of the whole circuit, and FIG. 3B is a side view of a main part of FIG.
4A and 4B illustrate the operation of a conventional circuit breaker, in which FIG. 4A is a single-phase simplified model diagram, and FIG. 4B is a curve diagram showing a stroke of a movable shaft.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Vacuum valve, 1a ... Movable shaft, 2 ... Support, 2a ... Long hole, 3 ... Donut-shaped copper plate, 4 ... Coil, 5 ... Frame, 6 ... Rod, 7 ... Pin, 8 ... Spring, 9 ... Connection bar, DESCRIPTION OF SYMBOLS 10 ... operation shaft, 11 ... electromagnetic actuator, 12 ... permanent magnet, 12a ... magnetic substance, 13 ... capacitor, 14 ... thyristor switch, 15 ... movable shaft, 15a ... long hole, 16 ... operation shaft, 17 ... support, F1 ... Electromagnetic repulsion, F2: magnetic attraction.

Claims

遮断部から引き出された可動軸に一端を遊びをもって結合された操作軸と、前記操作軸の他端に設けられ前記遮断部の閉路状態を保持する閉路状態保持手段と、前記操作軸に設けられ電磁反発作用を利用して前記操作軸を遮断方向へ駆動する開路操作手段とを備えたことを特徴とする遮断器。An operation shaft, one end of which is coupled with a play to the movable shaft drawn out of the blocking portion; a closed state holding means provided at the other end of the operation shaft for holding a closed state of the blocking portion; and A circuit breaker comprising: an open circuit operating means for driving the operation shaft in a breaking direction by utilizing an electromagnetic repulsion.

複数の遮断部に対して単一の開路操作手段および単一の閉路状態保持手段を備えたことを特徴とする請求項１記載の遮断器。2. The circuit breaker according to claim 1, further comprising a single open-circuit operating means and a single closed-circuit state maintaining means for a plurality of interrupters.