EP4679472A1

EP4679472A1 - Opening/closing device

Info

Publication number: EP4679472A1
Application number: EP23927306.3A
Authority: EP
Inventors: Yuma SAKATA; Shinichiro Nakauchi; Taiki Donen
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2023-03-10
Filing date: 2023-03-10
Publication date: 2026-01-14
Also published as: JP7362007B1; WO2024189682A1; EP4679472A4; JPWO2024189682A1

Abstract

A switch includes: a linkage (60) fixed to a vacuum valve (40) electrically connected to a first conductor (10); a unidirectional rotational-transmitter (80) attached to the linkage (60); a fixed contact (31) electrically connected to the first conductor (10); and a movable contact (32) electrically connected to a second conductor (20), the movable contact (32) including a hook (322), wherein the linkage (60) includes: a first link (61); a second link (62) rotatably fixed to the first link (61); and a third link (63) having one end portion (631) and another end portion (632), the one end portion (631) being rotatably fixed to the second link (62), the another end portion (632) being rotatably fixed to a movable-side electrode (43), and the unidirectional rotational-transmitter (80) is electrically connected to the movable-side electrode (43), and is rotatably fixed to the second link (62) and disposed on a movement locus of the hook (322).

Description

Field

The present disclosure relates to a switch that interrupts current in a vessel filled with insulating gas.

Background

Switches, such as a disconnector and a grounding switch to be used in a gas-insulated switch, employ a structure in which opening operation and closing operation are performed by the linear drive or rotational drive of a movable contact.
As compared with a switch to be used in a gas-insulated switch using SF₆ gas as an insulating medium, a switch to be used in a gas-insulated switch using dry air as an insulating medium has a longer duration of arc generation and a longer arc distance when current is interrupted in opening operation. As a result, the apparatus increases in size.
In the field of an excitation current switch disconnector to be used in an air disconnector or a miniaturized small power receiving and transforming facility, the following structure is employed in some cases, as in the interrupter disclosed in Patent Literature 1: a vacuum valve is disposed in parallel with a disconnection portion, as countermeasures against an arc, and current is interrupted between electrodes of the vacuum valve.

Citation List

Patent Literature

Patent Literature 1: Japanese Examined Patent Application Publication No. 48-18311

Summary of Invention

Problem to be solved by the Invention

If the vacuum valve is disposed in parallel with the disconnection portion as countermeasures against an arc, it is necessary to perform opening operation and closing operation at two locations, that is, the disconnection portion and the electrodes of the vacuum valve. This complicates the structure of the switch.
In addition, when the vacuum valve is disposed in parallel with the disconnection portion, voltage is constantly applied to the electrodes of the vacuum valve at the time of opening. Therefore, when the vacuum valve is disposed in parallel with the disconnection portion, it is necessary to use a large vacuum valve so as to withstand the duty of voltage.
Due to the above reasons, the switch in which the vacuum valve is disposed in parallel with the disconnection portion as countermeasures against an arc has the problem of causing a complicated apparatus configuration and an increase in apparatus size.
The present disclosure has been made in view of the above, and an object of the present disclosure is to obtain a switch that enables an arc to be extinguished by a vacuum valve and suppresses a complicated apparatus configuration and an increase in apparatus size.

Means to Solve the Problem

In order to solve the above-described problems and achieve the object, a switch according to the present disclosure is a switch adapted to open and close an electric circuit disposed in a tank in which insulating gas is enclosed, the switch including: a first conductor and a second conductor; a fixed contact electrically connected to the first conductor; a vacuum valve electrically connected to the first conductor; a linkage fixed to the vacuum valve; a unidirectional rotational-transmitter attached to the linkage; and a movable contact adapted to move rectilinearly between a closing position and an opening position, being electrically connected to the second conductor, being in contact with the fixed contact when located at the closing position, and being away from the fixed contact when located at the opening position. The vacuum valve includes: a vacuum vessel having a cylindrical shape; a fixed-side electrode disposed inside the vacuum vessel and electrically connected to the first conductor; a movable-side electrode disposed inside the vacuum vessel in such a way as to face the fixed-side electrode; and a bellows connecting the movable-side electrode and the vacuum vessel. The linkage includes: a first link fixed to the vacuum valve; a second link having one end portion rotatably fixed to the first link; and a third link having one end portion and another end portion, the one end portion being rotatably fixed to an intermediate portion of the second link, the another end portion being rotatably fixed to the movable-side electrode. The movable contact includes: a contact portion that is in contact with the fixed contact when located at the closing position; and a hook having a hook shape. The unidirectional rotational-transmitter: is rotatably fixed to another end portion of the second link and disposed on a movement locus of the contact portion; causes the second link to rotate about the one end portion of the second link by a force received from the hook in opening operation; and does not transmit the force received from the hook to the second link in closing operation, in which the movable contact moves from the opening position to the closing position.

Effects of the Invention

The switch according to the present disclosure achieves the effect of enabling an arc to be extinguished by a vacuum valve and enabling suppression of a complicated apparatus configuration and prevention of an increase in apparatus size.

Brief Description of Drawings

FIG. 1 is a diagram illustrating a configuration of a switch according to a first embodiment.
FIG. 2 is an enlarged view of a vacuum valve, a linkage, a unidirectional rotational-transmitter, a spring, and a linkage frame of the switch according to the first embodiment.
FIG. 3 is an enlarged view of the vacuum valve, the linkage, the unidirectional rotational-transmitter, the spring, and the linkage frame of the switch according to the first embodiment.
FIG. 4 is a diagram illustrating a state in which a hook is in contact with the unidirectional rotational-transmitter during opening operation of the switch according to the first embodiment.
FIG. 5 is a diagram illustrating a state in which a contact portion of a movable contact has come out of a hole in a fixed contact in the opening operation of the switch according to the first embodiment.
FIG. 6 is a diagram illustrating a state in which the hook of the movable contact has passed through the linkage frame in the opening operation of the switch according to the first embodiment.
FIG. 7 is a diagram illustrating a state in which the hook is in contact with the unidirectional rotational-transmitter during closing operation of the switch according to the first embodiment.
FIG. 8 is an enlarged view of a disconnection portion, a vacuum valve, a linkage, a unidirectional rotational-transmitter, a spring, and a linkage frame of a switch according to a second embodiment.
FIG. 9 is a diagram illustrating a configuration of a switch according to a third embodiment.
FIG. 10 is an enlarged view of a disconnection portion, a vacuum valve, a linkage, a unidirectional rotational-transmitter, a spring, and a linkage frame of the switch according to the third embodiment.
FIG. 11 is a diagram illustrating a state in which a hook is in contact with the unidirectional rotational-transmitter during opening operation of the switch according to the third embodiment.
FIG. 12 is a diagram illustrating a state in which the hook biases the unidirectional rotational-transmitter in a direction in which the unidirectional rotational-transmitter is pressed against a stopper during the opening operation of the switch according to the third embodiment.
FIG. 13 is a diagram illustrating a state in which the hook has come out of the linkage frame during the opening operation of the switch according to the third embodiment.
FIG. 14 is a diagram illustrating a state in which the hook is in contact with the unidirectional rotational-transmitter during closing operation of the switch according to the third embodiment.
FIG. 15 is an enlarged view of a disconnection portion, a vacuum valve, a linkage, a unidirectional rotational-transmitter, a spring, and a linkage frame of a switch according to a fourth embodiment.

Description of Embodiments

Hereinafter, switches according to embodiments will be described in detail with reference to the drawings.

First Embodiment.

FIG. 1 is a diagram illustrating a configuration of a switch according to a first embodiment. A disconnector 100, which is the switch according to the first embodiment, includes: a tank 50 in which insulating gas is enclosed; and a first conductor 10, and a second conductor 20 disposed inside the tank 50. Furthermore, the disconnector 100 includes: a disconnection portion 30 including a fixed contact 31 and a movable contact 32; and a vacuum valve 40 adapted to interrupt a current. In addition, the disconnector 100 includes: a linkage 60 disposed at an end of the vacuum valve 40 on a side opposite to a side fixed to the first conductor 10; and a linkage frame 70 adapted to cover the linkage 60. The movable contact 32 is fixed to the second conductor 20. A hole 311 is formed on a surface of the fixed contact 31 facing the movable contact 32. The movable contact 32 moves rectilinearly when a driving force is transmitted from an operation device (not illustrated). The movable contact 32 has a bifurcated end, and includes a contact portion 321 and a hook 322. The contact portion 321 can be inserted into the hole 311 in the fixed contact 31. The hook 322 is disposed in parallel with the contact portion 321. Note that the movable contact 32 having a bifurcated end is described here as an example, but the movable contact 32 just needs to include the contact portion 321 and the hook 322, and is not limited to a shape with a bifurcated end.
The disconnector 100 is incorporated in a gas-insulated switch 300, and is separated from other devices by an insulating spacer 200.
The disconnector 100 illustrated in FIG. 1 is in a closed state in which the movable contact 32 is in contact with the fixed contact 31 and thus, current flows between the first conductor 10 and the second conductor 20 through the movable contact 32 and the fixed contact 31. When the movable contact 32 is separated from the fixed contact 31 by the driving force from the operation device (not illustrated) and no current flows between the first conductor 10 and the second conductor 20, the disconnector 100 enters an open state. Hereinafter, operation for shifting from the closed state to the open state is referred to as opening operation, and operation for shifting from the open state to the closed state is referred to as closing operation.
FIGS. 2 and 3 are enlarged views of the vacuum valve, the linkage, a unidirectional rotational-transmitter, a spring, and the linkage frame of the switch according to the first embodiment. FIG. 3 illustrates the vacuum valve 40, the linkage 60, a unidirectional rotational-transmitter 80, a spring 90, and the linkage frame 70, as viewed from a direction of arrow A in FIG. 1. The vacuum valve 40 includes: a vacuum vessel 41 having a cylindrical shape; a fixed-side electrode 42 disposed inside the vacuum vessel 41; a movable-side electrode 43 disposed inside the vacuum vessel 41 in such a way as to face the fixed-side electrode 42; and a bellows unit 44 that connects the movable-side electrode 43 and the vacuum vessel 41. The fixed-side electrode 42 includes: a fixed-side electrode rod 421 that extends like a rod; and a fixed-side contact 422 that is provided at one end 421a of the fixed-side electrode rod 421. The movable-side electrode 43 includes: a movable-side electrode rod 431 that penetrates another end 412 of the vacuum vessel 41, and extends to the outside of the vacuum vessel 41; and a movable-side contact 432 provided at one end 431a of the movable-side electrode rod 431. The bellows unit 44 includes: an end plate 441 fixed to the movable-side electrode rod 431; and a bellows 442 that connects the another end 412 of the vacuum vessel 41 and the end plate 441. Another end 421b of the fixed-side electrode rod 421 is connected to the first conductor 10. Another end 431b of the movable-side electrode rod 431 is connected to the linkage 60 at outside the vacuum vessel 41.
The linkage 60 includes: a first link 61 fixed to the another end 412 of the vacuum vessel 41; a second link 62 of which one end portion 621 is rotatably fixed to the first link 61; and a third link 63 having one end portion 631 that is rotatably fixed to an intermediate portion 624 between the one end portion 621 and another end portion 622 of the second link 62. The linkage 60 includes: the unidirectional rotational-transmitter 80 rotatably fixed to the another end portion 622 of the second link 62; and the spring 90 that connects the second link 62 and the unidirectional rotational-transmitter 80. Another end portion 632 of the third link 63 is rotatably fixed to the another end 431b of the movable-side electrode rod 431. A stopper 623 that restricts rotation of the unidirectional rotational-transmitter 80 is formed at the another end portion 622 of the second link 62. The unidirectional rotational-transmitter 80 can rotate up to a position where the unidirectional rotational-transmitter 80 comes into contact with the stopper 623. The spring 90 biases the unidirectional rotational-transmitter 80 by an elastic force in a direction in which the unidirectional rotational-transmitter 80 comes into contact with the stopper 623. The second link 62, the third link 63, and the unidirectional rotational-transmitter 80 are formed of electrically conductive material. Therefore, the movable-side electrode 43 and the unidirectional rotational-transmitter 80 are electrically connected by the third link 63 and the second link 62. The unidirectional rotational-transmitter 80 is disposed on an operation locus of the hook 322.
The linkage 60, the unidirectional rotational-transmitter 80, and the spring 90 are covered with the linkage frame 70 that is dome-shaped. The linkage frame 70 is formed of electrically conductive material, and shields the linkage 60, the unidirectional rotational-transmitter 80, and the spring 90 from an electric field in the tank 50. A gap 71 through which the hook 322 can pass is formed in the linkage frame 70.
In a state where no external force is applied to the linkage 60, the bellows 442 extends due to pressure of the insulating gas in the tank 50, and the movable-side contact 432 is in contact with the fixed-side contact 422.
The opening operation will be described. When the movable contact 32 having received the driving force from the operation device (not illustrated) moves in a direction to be away from the fixed contact 31, the hook 322 passes through a gap 71 in the linkage frame 70, and comes into contact with a unidirectional rotational-transmitter 80 disposed inside the linkage frame 70. FIG. 4 is a diagram illustrating a state in which the hook is in contact with the unidirectional rotational-transmitter during the opening operation of the switch according to the first embodiment. When the hook 322 comes into contact with the unidirectional rotational-transmitter 80, the contact portion 321 has not come out of the hole 311 in the fixed contact 31. Thus, current flows between the first conductor 10 and the second conductor 20 on both a path through the fixed contact 31 and the contact portion 321 and a path through the vacuum valve 40, the linkage 60, the unidirectional rotational-transmitter 80, and the hook 322.
FIG. 5 is a diagram illustrating a state in which the contact portion of the movable contact has come out of the hole in the fixed contact in the opening operation of the switch according to the first embodiment. When the movable contact 32 further moves in the direction away from the fixed contact 31, the contact portion 321 comes out of the hole 311 in the fixed contact 31, and the hook 322 biases the unidirectional rotational-transmitter 80 in a direction in which the unidirectional rotational-transmitter 80 is pressed against a stopper 623. As a result of the contact portion 321 having come out of the hole 311 in the fixed contact 31, current flows between the first conductor 10 and the second conductor 20 only on the path through the vacuum valve 40, the linkage 60, the unidirectional rotational-transmitter 80, and the hook 322. As a result of the unidirectional rotational-transmitter 80 being pressed against the stopper 623, the second link 62 rotates about a portion rotatably fixed to the first link 61. The rotation of the second link 62 causes the third link 63 to move the movable-side electrode rod 431 in a direction in which the movable-side electrode rod 431 is pulled out of the vacuum vessel 41. As a result, the movable-side contact 432 is separated from the fixed-side contact 422. Separation of the movable-side contact 432 from the fixed-side contact 422 interrupts the current flowing between the first conductor 10 and the second conductor 20. When the movable-side electrode rod 431 moves in the direction in which the movable-side electrode rod 431 is pulled out of the vacuum vessel 41, the bellows 442 is compressed.
FIG. 6 is a diagram illustrating a state in which the hook of the movable contact has passed through the linkage frame in the opening operation of the switch according to the first embodiment. When the hook 322 is separated from the unidirectional rotational-transmitter 80, no external force is applied to the linkage 60. When application of external force to the linkage 60 is stopped, the bellows 442 compressed during the opening operation is extended by pressure of the gas in the tank 50. As a result, the movable-side electrode rod 431 drawn out of the vacuum vessel 41 is drawn into the vacuum vessel 41. Drawing the movable-side electrode rod 431 into the vacuum vessel 41 causes the third link 63 to rotate the second link 62, so that the hook 322 returns to a position where the hook 322 has not yet been brought into contact with the unidirectional rotational-transmitter 80. When the movable-side contact 432 is in contact with the fixed-side contact 422, the movable-side contact 432 and the fixed-side contact 422 are at the same electric potential.
Next, the closing operation will be described. FIG. 7 is a diagram illustrating a state in which the hook is in contact with the unidirectional rotational-transmitter during the closing operation of the switch according to the first embodiment. When the movable contact 32 moves toward the fixed contact 31 by the driving force from the operation device (not illustrated), the hook 322 passes through the gap 71 in the linkage frame 70, and comes into contact with the unidirectional rotational-transmitter 80 disposed inside the linkage frame 70. In the closing operation, the hook 322 comes into contact with the unidirectional rotational-transmitter 80 from a direction opposite to that in the opening operation. Since the unidirectional rotational-transmitter 80 does not come into contact with the stopper 623 in the closing operation, the unidirectional rotational-transmitter 80 does not transmit a turning force to the second link 62.
As a result of the movable contact 32 moving toward the fixed contact 31, the contact portion 321 is inserted into the hole 311 in the fixed contact 31. Insertion of the contact portion 321 into the hole 311 in the fixed contact 31 causes current to flow between the first conductor 10 and the second conductor 20 through the contact portion 321 and the fixed contact 31.
When the hook 322 has passed through the linkage frame 70, the unidirectional rotational-transmitter 80 is returned to a position where the unidirectional rotational-transmitter 80 is in contact with the stopper 623 by the elastic force of a spring 90.
The disconnector 100, which is the switch according to the first embodiment, includes the first link 61, the second link 62, and the third link 63. The first link 61 is fixed to the another end 412 of the vacuum vessel 41. The second link 62 has the one end portion 621 rotatably fixed to the first link 61. The third link 63 has the one end portion 631 rotatably fixed to the intermediate portion 624 between the one end portion 621 and the another end portion 622 of the second link 62. Therefore, it is possible to open the vacuum valve 40 by using the driving force applied to the movable contact 32, so that the vacuum valve 40 can enter the open state by using the pressure of the insulating gas in the tank 50. Therefore, it is not necessary to provide a mechanism for transmitting, to the vacuum valve 40, a driving force from an operation device for the vacuum valve 40 different from an operation device for opening and closing the disconnection portion 30. Thus, the configuration of the apparatus can be simplified. Furthermore, the movable-side contact 432 and the fixed-side contact 422 of the vacuum valve 40 are in contact with each other and at the same electric potential in the open state, so that no voltage is applied therebetween. Therefore, it is not necessary to use the vacuum valve 40 that is large in size and thus, the apparatus can be downsized.

Second Embodiment.

FIG. 8 is an enlarged view of a disconnection portion, a vacuum valve, a linkage, a unidirectional rotational-transmitter, a spring, and a linkage frame of a switch according to a second embodiment. The disconnector 100 that is the switch according to the second embodiment includes a flexible conductor 91 that electrically connects the movable-side electrode rod 431 and the unidirectional rotational-transmitter 80. In the disconnector 100 according to the second embodiment, the second link 62 and the third link 63 are formed of insulating material. That is, the entire linkage 60 is formed of insulating material in the disconnector 100 according to the second embodiment. Except for this point, the disconnector 100 according to the present embodiment is the same as the disconnector 100 according to the first embodiment.
In the disconnector 100 according to the second embodiment, the entire linkage 60 is formed of insulating material. Therefore, it is possible to prevent generation of conductive abrasion powder due to friction during operation of the linkage 60.
As with the disconnector 100 according to the first embodiment, the disconnector 100 according to the second embodiment does not require a mechanism for transmitting, to the vacuum valve 40, a driving force from an operation device for the vacuum valve 40 different from an operation device for opening and closing the disconnection portion 30. Thus, the configuration of the apparatus can be simplified. Furthermore, the movable-side contact 432 and the fixed-side contact 422 of the vacuum valve 40 are in contact with each other and at the same electric potential in the open state, so that no voltage is applied therebetween. Therefore, it is not necessary to use the vacuum valve 40 that is large in size and thus, the apparatus can be downsized.

Third Embodiment.

FIG. 9 is a diagram illustrating a configuration of a switch according to a third embodiment. FIG. 10 is an enlarged view of a disconnection portion, a vacuum valve, a linkage, a unidirectional rotational-transmitter, a spring, and a linkage frame of the switch according to the third embodiment. In the disconnector 100 which is the switch according to the third embodiment, the linkage frame 70 covers the entire vacuum valve 40 in addition to the linkage 60, the unidirectional rotational-transmitter 80, and the spring 90. A hole 72 is formed in the linkage frame 70, and the fixed contact 31 that is a tulip-type fixed contact is disposed at an edge of the hole 72. The fixed contact 31 is electrically connected to the first conductor 10 through the linkage frame 70. The hook 322 of the movable contact 32 is disposed at a tip of the contact portion 321 that is round bar-shaped. Except for this point, the disconnector 100 according to the present embodiment is the same as the disconnector 100 according to the first embodiment.
The opening operation will be described. When the movable contact 32 having received a driving force from the operation device (not illustrated) moves in a direction in which the contact portion 321 comes out of the fixed contact 31, the hook 322 comes into contact with the unidirectional rotational-transmitter 80 disposed inside the linkage frame 70. FIG. 11 is a diagram illustrating a state in which the hook is in contact with the unidirectional rotational-transmitter during the opening operation of the switch according to the third embodiment. When the hook 322 comes into contact with the unidirectional rotational-transmitter 80, the contact portion 321 is in contact with the fixed contact 31. Thus, current flows between the first conductor 10 and the second conductor 20 on both: a path through the fixed contact 31 and the contact portion 321; and a path through the vacuum valve 40, the linkage 60, the unidirectional rotational-transmitter 80, the hook 322, and the contact portion 321.
When the movable contact 32 further moves in the direction in which the contact portion 321 comes out of the fixed contact 31, the contact portion 321 comes out of the fixed contact 31, and the hook 322 biases the unidirectional rotational-transmitter 80 in a direction in which the unidirectional rotational-transmitter 80 is pressed against the stopper 623. FIG. 12 is a diagram illustrating a state in which the hook biases the unidirectional rotational-transmitter in the direction in which the unidirectional rotational-transmitter is pressed against the stopper during the opening operation of the switch according to the third embodiment. As a result of the contact portion 321 having come out of the fixed contact 31, current flows between the first conductor 10 and the second conductor 20 only on the path through the vacuum valve 40, the linkage 60, the unidirectional rotational-transmitter 80, the hook 322, and the contact portion 321. As a result of the unidirectional rotational-transmitter 80 being pressed against the stopper 623, the second link 62 rotates about a portion rotatably fixed to the first link 61. The rotation of the second link 62 causes the third link 63 to move the movable-side electrode rod 431 in a direction in which the movable-side electrode rod 431 is pulled out of the vacuum vessel 41. As a result, the movable-side contact 432 is separated from the fixed-side contact 422. Separation of the movable-side contact 432 from the fixed-side contact 422 causes the current flowing between the first conductor 10 and the second conductor 20 to be interrupted.
FIG. 13 is a diagram illustrating a state in which the hook has come out of the linkage frame during the opening operation of the switch according to the third embodiment. When the hook 322 is separated from the unidirectional rotational-transmitter 80, no external force is applied to the linkage 60. When application of external force to the linkage 60 is stopped, the bellows 442 compressed during the opening operation is extended by pressure of the gas in the tank 50. As a result, the movable-side electrode rod 431 drawn out of the vacuum vessel 41 is drawn into the vacuum vessel 41. Drawing the movable-side electrode rod 431 into the vacuum vessel 41 causes the third link 63 to rotate the second link 62, so that the hook 322 returns to a position where the hook 322 has not yet been brought into contact with the unidirectional rotational-transmitter 80. When the movable-side contact 432 is in contact with the fixed-side contact 422, the movable-side contact 432 and the fixed-side contact 422 are at the same electric potential.
Next, the closing operation will be described. The movable contact 32 moves toward the fixed contact 31 by the driving force from the operation device (not illustrated). FIG. 14 is a diagram illustrating a state in which the hook is in contact with the unidirectional rotational-transmitter during the closing operation of the switch according to the third embodiment. The hook 322 enters the inside of the linkage frame 70 through the hole 72 in the linkage frame 70, and comes into contact with the unidirectional rotational-transmitter 80 disposed inside the linkage frame 70. In the closing operation, the hook 322 comes into contact with the unidirectional rotational-transmitter 80 from a direction opposite to that in the opening operation. Since the unidirectional rotational-transmitter 80 does not come into contact with the stopper 623 in the closing operation, the unidirectional rotational-transmitter 80 does not transmit a turning force to the second link 62.
As a result of the movable contact 32 moving toward the fixed contact 31, the contact portion 321 is inserted into the fixed contact 31. Insertion of the contact portion 321 into the fixed contact 31 causes current to flow between the first conductor 10 and the second conductor 20 through the contact portion 321 and the fixed contact 31. The unidirectional rotational-transmitter 80 is returned to a position where the unidirectional rotational-transmitter 80 is in contact with the stopper 623 by the elastic force of the spring 90.
Similarly to the disconnectors 100 according to the first and second embodiments, the disconnector 100 according to the third embodiment does not require a mechanism for transmitting, to the vacuum valve 40, a driving force from an operation device for the vacuum valve 40 different from an operation device for opening and closing the disconnection portion 30. Thus, the configuration of the apparatus can be simplified. Furthermore, the movable-side contact 432 and the fixed-side contact 422 of the vacuum valve 40 are in contact with each other and at the same electric potential in the open state, so that no voltage is applied therebetween. Therefore, it is not necessary to use the vacuum valve 40 that is large in size and thus, the apparatus can be downsized.

Fourth Embodiment.

FIG. 15 is an enlarged view of a disconnection portion, a vacuum valve, a linkage, a unidirectional rotational-transmitter, a spring, and a linkage frame of a switch according to a fourth embodiment. The disconnector 100 that is the switch according to the fourth embodiment includes a flexible conductor 91 that electrically connects the movable-side electrode rod 431 and the unidirectional rotational-transmitter 80. In the disconnector 100 according to the fourth embodiment, the second link 62 and the third link 63 are formed of insulating material. That is, the entire linkage 60 is formed of insulating material in the disconnector 100 according to the fourth embodiment. Except for this point, the disconnector 100 according to the present embodiment is the same as the disconnector 100 according to the third embodiment.
In the disconnector 100 according to the fourth embodiment, the entire linkage 60 is formed of insulating material. It is thus possible to prevent generation of conductive abrasion powder due to friction during operation of the linkage 60.
Similarly to the disconnectors 100 according to the first, second, and third embodiments, the disconnector 100 according to the fourth embodiment does not require a mechanism for transmitting, to the vacuum valve 40, a driving force from an operation device for the vacuum valve 40 different from an operation device for opening and closing the disconnection portion 30. Thus, the configuration of the apparatus can be simplified. Furthermore, the movable-side contact 432 and the fixed-side contact 422 of the vacuum valve 40 are in contact with each other and at the same electric potential in the open state, so that no voltage is applied therebetween. Therefore, it is not necessary to use the vacuum valve 40 that is large in size and thus, the apparatus can be downsized.
Note that it is also possible to use the switches according to the first, second, third, and fourth embodiments as a grounding switch by adopting a configuration in which the movable contact 32 can move to a grounding position where the movable contact 32 is grounded.
The configurations set forth in the above embodiments show examples of the subject matter, and it is possible to combine the configurations with another known technique, and is also possible to partially omit or change the configurations without departing from the scope of the present disclosure.

Reference Signs List

10 first conductor; 20 second conductor; 30 disconnection portion; 31 fixed contact; 32 movable contact; 40 vacuum valve; 41 vacuum vessel; 42 fixed-side electrode; 43 movable-side electrode; 44 bellows unit; 50 tank; 60 linkage; 61 first link; 62 second link; 63 third link; 70 linkage frame; 71 gap; 72, 311 hole; 80 unidirectional rotational-transmitter; 90 spring; 91 flexible conductor; 100 disconnector; 200 insulating spacer; 300 gas-insulated switch; 321 contact portion; 322 hook; 411, 421a, 431a one end; 412, 421b, 431b another end; 421 fixed-side electrode rod; 422 fixed-side contact; 431 movable-side electrode rod; 432 movable-side contact; 441 end plate; 442 bellows; 621, 631 one end portion; 622, 632 another end portion; 623 stopper; 624 intermediate portion.

Claims

A switch adapted to open and close an electric circuit in a tank in which insulating gas is enclosed, the switch comprising:
a first conductor and a second conductor;

a fixed contact electrically connected to the first conductor;

a vacuum valve electrically connected to the first conductor;

a linkage fixed to the vacuum valve;

a unidirectional rotational-transmitter attached to the linkage; and

a movable contact:
electrically connected to the second conductor; and

adapted to move rectilinearly between a closing position and an opening position that is away from the fixed contact, wherein

the vacuum valve includes:
a vacuum vessel having a cylindrical shape;

a fixed-side electrode disposed inside the vacuum vessel and electrically connected to the first conductor;

a movable-side electrode disposed inside the vacuum vessel in such a way as to face the fixed-side electrode; and

a bellows connecting the movable-side electrode and the vacuum vessel,

the linkage includes:
a first link fixed to the vacuum valve;

a second link having one end portion rotatably fixed to the first link; and

a third link having one end portion rotatably fixed to an intermediate portion of the second link, and another end portion rotatably fixed to the movable-side electrode,

the movable contact includes:
a contact portion that is in contact with the fixed contact when located at the closing position; and

a hook having a hook shape, wherein

the unidirectional rotational-transmitter:
is rotatably fixed to another end portion of the second link and disposed on a movement locus of the contact portion;

causes the second link to be rotated about the one end portion of the second link by a force received from the hook in opening operation; and

does not transmit the force received from the hook to the second link in closing operation in which the movable contact moves from the opening position to the closing position.
The switch according to claim 1, wherein
the second link includes a stopper adapted to restrict rotation of the unidirectional rotational-transmitter by coming into contact with the unidirectional rotational-transmitter during the opening operation.
The switch according to claim 2, comprising:
a spring adapted to bias the unidirectional rotational-transmitter in a direction in which the unidirectional rotational-transmitter is pressed against the stopper, the spring being disposed in the tank.
The switch according to claim 1, wherein
the second link and the third link are formed of electrically conductive material.
The switch according to claim 1, comprising:
a flexible conductor adapted to connect the movable-side electrode and the unidirectional rotational-transmitter, the flexible conductor being located in the tank.
The switch according to claim 1, wherein
when no external force is applied to the linkage, the bellows is extended by pressure of the insulating gas, to bring the movable-side electrode into contact with the fixed-side electrode.
The switch according to any one of claims 1 to 6, wherein
the hook and the contact portion are disposed side by side in a direction orthogonal to a direction of rectilinear movement of the movable contact.
The switch according to any one of claims 1 to 6, wherein
the hook and the contact portion are disposed along a direction of rectilinear movement of the movable contact.