JPH1146410A - Interlock device for electrical facility - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely inhibit the movement of a circuit breaker to a connecting position when an earthing switch is in an earthing state without giving any influence to the operating mechanism of the earthing switch. SOLUTION: An operating shaft 7 is installed along the moving route of a circuit breaker 40 in a circuit breaker chamber 4, so that an earthing switch 6 in a transmission chamber 3 may be earthed and canceled from an earthing state by rotationally operating the shaft 7. A lock lever 8 which oscillates in association with the rotation of the shaft 7 is attached to the middle of the shaft 7, so that the lever 8 may project onto the floor plate 4b of the circuit breaker chamber 3, and restrict the movement of the circuit breaker 40 to a connecting position when the earthing switch 6 is set to an earthing state.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an interlock device for electrical equipment, comprising a circuit breaker for connecting and disconnecting a bus-side branch conductor and a load-side conductor, and a grounding switch for grounding and releasing the load-side conductor. .

[0002]

2. Description of the Related Art In a closed switchboard, a plurality of compartments are formed by partitioning the inside of an outer box constituted as a box made of a grounded metal from each other by a partition made of a grounded metal or an insulating material, and forming a plurality of compartments. , A bus-side branch conductor connected to a common bus, a load-side conductor connected to a power transmission cable for transmitting power to loads such as other electric rooms and load equipment, a switchgear that connects and separates both conductors, and monitoring control. The configuration accommodates internal devices such as necessary control devices.

In such a closed switchboard, it is necessary to eliminate the voltage of the internal equipment before the inspection in order to prevent an electric shock accident of the inspection operator due to the residual voltage of the internal equipment at the time of the internal inspection of each of the installation rooms. is there. In particular, in the installation room of the load-side conductor where high voltage may remain, a grounding switch for grounding and releasing the load-side conductor by an external operation is provided. After the circuit breaker is pulled out in the disposition room and the bus-side branch conductor and the load-side conductor are surely disconnected, the load-side conductor is made non-voltage by grounding the grounding switch.

However, in electrical equipment such as a closed switchboard provided with a circuit breaker and a grounding switch as described above, when the grounding switch is grounded without the circuit breaker being pulled out to the disconnection position, or when the grounding switch is operated. If the circuit breaker is moved to the connection position while the grounding operation is being performed, the bus may be grounded via the load-side conductor and the bus-side branch conductor. An interlock device as disclosed in JP-A-53-131449 and JP-A-63-100902 is provided.

[0005]

However, Japanese Patent Application Laid-Open No.
The interlock device disclosed in Japanese Patent Publication No. 131449 discloses that when a grounding switch is in a state where a grounding operation is performed, a lever connected to a movable portion of the grounding switch by a wire swings in a breaker room, and a disconnection occurs. This is merely to prevent the circuit breaker from moving from the position to the connection position, that is, to prevent the circuit breaker from being pushed in, and can prevent the grounding switch from being grounded without the circuit breaker being pulled out to the disconnection position. However, one of the problems described above is incomplete and cannot be solved.

Further, since the lever for preventing the movement of the circuit breaker is connected to the grounding switch itself by a wire, the impact applied to the lever when the circuit breaker is pushed is transmitted directly to the grounding switch, and the grounding switch is connected to the grounding switch. There was a problem that the durability of the switch was impaired.

On the other hand, the interlock device disclosed in Japanese Utility Model Laid-Open Publication No. 63-100902 moves a rod mechanically connected to an operating mechanism of a grounding switch into and out of a breaker room.
When the grounding switch is grounded, the rod protruding into the breaker chamber comes into contact with a guide plate provided on a part of the breaker to prevent the breaker from being pushed in while the breaker is connected. When the grounding switch is to be grounded in the position, the rod protruding into the circuit breaker chamber comes into contact with the guide plate, thereby preventing the rod from advancing.
The grounding operation is disabled, and the two problems described above can be solved together.

However, the grounding switch is configured as a link mechanism in which an operating lever that is oscillated and a movable portion of the grounding switch are connected via a link.
Since it is configured to be connected to the operation lever and move back and forth with the swing of the operation lever, as in the configuration disclosed in JP-A-53-131449, it is necessary to move to the connection position. When the breaker is pushed in, the impact applied to the rod is transmitted to the movable part of the grounding switch via the operating lever and link, and the durability of the operating mechanism of the grounding switch including the operating lever and link is impaired. There is.

Further, it is necessary to provide the guide plate, which is a component unnecessary for its original operation, on the circuit breaker side, and there is a problem that a special design is required.

The present invention has been made in view of such circumstances, and it is possible to reliably prevent the breaker from being pushed to the connection position without affecting the operation mechanism of the grounding switch. An object of the present invention is to provide an interlock device that does not impair the durability of an operation mechanism by a simple configuration that does not require any special parts on the circuit breaker side.

[0011]

According to a first aspect of the present invention, there is provided an interlock device for electric equipment, wherein an operation shaft for operating a grounding switch by rotation about an axis is erected along a moving path of the circuit breaker. The lock lever attached in the middle of the operation shaft is configured to move back and forth into the movement path.

In the present invention, when the grounding switch is grounded by turning the operation shaft with the circuit breaker pulled out to the disconnecting position, the lock lever projects into the movement path of the circuit breaker. When the circuit breaker is to be pushed into the connection position in this state, the lock lever comes into contact with a part of the circuit breaker to prevent further pushing. When the grounding switch is to be grounded while the circuit breaker is in the connection position, the lock lever projecting into the movement path of the circuit breaker in accordance with the turning operation of the operation shaft for this purpose is moved to the connection position. A part of the circuit breaker, and prevents further rotation of the operating shaft to disable the grounding operation.

According to a second aspect of the present invention, there is provided an interlock device for electric equipment, wherein an operation shaft is disposed at a position below a movement path of a circuit breaker.

According to the present invention, the operating shaft of the grounding switch is arranged below the moving path of the circuit breaker, and the lock lever attached to this operating shaft is securely connected to the circuit breaker on the moving path from the lower surface thereof. Abut.

According to a third aspect of the present invention, there is provided an interlock device for electrical equipment, wherein a contact piece having a length corresponding to a movement stroke of a circuit breaker is provided at a protruding end of a lock lever to a movement path of the circuit breaker. It is a thing.

According to the present invention, when the lock lever protrudes in accordance with the grounding operation of the grounding switch, the contact piece provided at the protruding end portion moves from the disconnection position of the circuit breaker to the connection position on the moving path. And reliably prevents the circuit breaker from being pushed in at the disconnection position when the grounding switch is in the grounded state, and the circuit breaker is located at an intermediate position between the disconnection position and the connection position. Even in a state in which the grounding switch is in an appropriate position, the grounding operation of the grounding switch is disabled by the contacting piece contacting the circuit breaker.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the drawings showing the embodiments. FIG. 1 is a side sectional view schematically showing the overall configuration of a closed switchboard provided with an interlock device according to the present invention.

The closed switchboard includes a rectangular box-shaped outer case 1 made of a grounding metal, which is partitioned by a partition wall made of a grounding metal or an insulating material, and a busbar room 2 in which a busbar-side branch conductor 20 is disposed, and a load. A cable room 3 in which the side conductor 30 is disposed, a circuit breaker room 4 in which a circuit breaker 40 as a switchgear is stored, and a control device room 5 in which a control device (not shown) is stored are formed. I have.

A circuit breaker room 4 is formed in the lower part of the front half (the left part of FIG. 1) of the outer box 1 and a control equipment room 5 is formed in the upper part thereof. Front doors 10, 11
The cover is openable and closable. The rear half of the circuit breaker room 4 extends in the height direction along the rear side of the control device room 5,
The upper part thereof is connected to the top plate of the outer box 1. The extension 4a serves as an air passage for releasing the internal pressure rise when an accident inside the circuit breaker room 4 occurs. It is used as a radiating air path for the circuit breaker 40.

The circuit breaker 40 is mounted on a carriage 41 which can move back and forth along the bottom plate 4b of the circuit breaker room 4. On the rear wall of the breaker room 4, disconnecting portions 42 and 43 of the main circuit are fixed at predetermined intervals vertically with the connection opening facing forward, and the breaker 40 is A connection position in which connection terminals 44, 44 (only one of them is shown) which are pushed into the inner side of the circuit breaker chamber 4 together with 41 and project from the rear surface are engaged with the disconnecting portions 42, 43;
It is pulled out to the front position of the circuit breaker room 4 together with the carriage 41, and can be moved between the disconnecting portions 42 and 43 and a disconnecting position separated by a sufficient insulating distance.

The busbar chamber 2 is formed on the rear side of the circuit breaker chamber 4 and includes a projecting position of the disconnecting portion 42 at a lower portion thereof.
In the upper part of the bus chamber 2, three bus-side branch conductors 20, 20, 20 connected to three-phase buses (not shown) are respectively provided with insulators 21, 20.
The lower portions of the bus-bar-side branch conductors 20, 20, 20 are connected to the disconnecting section 42. FIG. 1 shows single disconnecting portions 42 and 43, respectively, which are juxtaposed in the thickness direction of the drawing so as to correspond to each of the three phases. 20,
Reference numerals 20, 20 are connected to corresponding disconnecting portions 42, 42, 42, respectively.

The cable room 3 is formed on the rear side of the bus room 2 over substantially the entire height of the outer box 1. The lower portion of the cable room 3 is separated by the lower wall of the bus room 2 and extends forward. The disconnecting portion 43 faces the rear side of the circuit breaker chamber 4. A power transmission cable C is drawn into the cable chamber 3 from the bottom surface of the outer box 1, and the power transmission cable C is connected to a load-side conductor 30 that is insulated and supported in the middle by insulators 31 and 32. .

The load-side conductors 30 are juxtaposed in the thickness direction of the paper so as to correspond to each of the three phases, similarly to the disconnecting portions 42 and 43. It is connected. An intermediate portion of the load-side conductor 30 is inserted into a transformer 33 disposed between the insulators 31 and 32, and the current transmitted to the load-side conductor 30 in response to turning on of the circuit breaker 40 is changed by the transformer. It is modified by 33 and is sent to the control equipment inside the control equipment room 5.

A connecting conductor 34 is connected to the projecting portion of the disconnecting portion 43 into the cable chamber 3 together with the load-side conductor 30 so as to project rearward and downward. The grounding switch 6 is attached to the lower side of the rear end of the connection conductor 34. The grounding switch 6 is mounted on a base 60 fixed to the bottom surface of the outer box 1 in a grounded state, as shown in FIG.
A conductor 62 insulated and supported by an insulator 61 and resiliently contacts the connection conductor 34 from below, and a contact 63 swinging around a support shaft extending in the left-right direction are provided. By operating the contact 63 from the front position of the chamber 4, the contact 63 is erected as shown by a broken line in the figure, and the tip of the contact 63 is brought into contact with the conductor 62. The operation of grounding 30 is performed.

The rear side of the cable room 3 as described above is
The cable room 3 including the load-side conductor 30 is covered with a pair of upper and lower back lids 12 and 13 attached to the back of the
Inspection of the internal equipment of the back cover 12 as an inspection cover,
13 is removed and the back of the cable room 3 is opened,
The grounding switch 6 is operated to ground the load-side conductor 30 prior to the inspection work.

FIGS. 2 and 3 are explanatory views of the operation of the interlock device according to the present invention, in which the vicinity of the positions where the circuit breaker chamber 4 and the earthing switch 6 are disposed is enlarged. As described above, the grounding switch 6 performs an operation of grounding the connection conductor 34 and the load-side conductor 30 by bringing the tip of the contact 63 supported on the base 60 into contact with the conductor 62 arranged above. It is. The base end of the contact 63 is pivotally supported by a substantially horizontal support shaft 64 extending in the width direction of the outer box 1 so as to be swingable with respect to the base 60. The support shaft 64 protruding toward
A base end of a swing lever 65 is fixed to an end of the swing lever 65. A lever 67 that swings around a support shaft 66 parallel to the support shaft 64 is provided at a position slightly in front of the grounding switch 6.
Is connected to the tip of the swing lever 65 via a connection link 68.

On the other hand, inside the circuit breaker room 4 in which the circuit breaker 40 is housed,
An operation shaft 7 is installed with the axial direction facing forward and backward. The operating shaft 7 is rotatably supported around its axis, and its front end is protruded at a suitable position in front of the circuit breaker room 4 covered with the front door 10, and its rear end is The lever 67 extends to the front lower portion of the cable chamber 3 and faces the support shaft 66 of the lever 67.

FIG. 4 is a plan view showing the connection between the operation shaft 7 and the support shaft 66. As shown, the rear end of the operation shaft 7 is
The shaft ends are abutted on the shaft end of the support shaft 66 so that their respective axial length directions are substantially orthogonal to each other. Bevel gears 70 and 69 fitted to these shafts are meshed with each other, and the operation shaft 7 is rotated around the shaft. When rotating, the rotation is transmitted to the support shaft 66 by changing the direction by the meshing portions of the bevel gears 70 and 69, and the support shaft 66 rotates.

The operating shaft 71 is fitted with an operating handle 71 as shown by a two-dot chain line in FIG. 2 at the front end exposed at the front lower portion of the circuit breaker chamber 4 when the front door 10 is opened.
Rotational operation can be performed via 71. FIG. 2 shows a case where the grounding switch 6 is in the ground release state. At this time, the contact 63 of the grounding switch 6 is tilted with its tip facing backward, and has a sufficient insulation distance from the upper conductor 62. And the connection conductor 34 and the load-side conductor 30 are not grounded.

In this state, when the operation handle 71 is fitted and the operation shaft 7 is rotated clockwise, the lever 67 is rotated by the rotation of the support shaft 66 connected to the rear end of the operation shaft 7 so that the lever 67 2, swings counterclockwise as indicated by the arrow, and this swing is transmitted to the swing lever 65 via the connecting link 68, and the swing lever 65 swings counterclockwise together with the support shaft 64. The contact 63 rises on the base 60 as shown in FIG. 3, and the tip of the contact 63 elastically contacts the upper conductor 62,
The connection conductor 34 and the load-side conductor 30 are grounded via the conductor 62. The grounding state of the grounding switch 6 is determined by a closing spring interposed between the base 60 and the swing lever 65.
It is held by the spring force of 65a.

The operation of the earthing switch 6 as described above is based on the fact that the circuit breaker 40 in the circuit breaker chamber 4 is connected to the disconnecting section as shown in FIG.
This is possible only in a state where the circuit breaker is pulled out to a disconnection position sufficiently distant from 43 (and 42), and when the grounding switch 6 is grounded, the circuit breaker 40 is moved to the connection position.
, That is, the circuit breaker 40 cannot be pushed in. In the present invention, such an interlock operation is performed by a lock lever 8 attached in the middle of the operation shaft 7. .

As shown in FIG. 2 and FIG.
Is mounted on the operation shaft 7 at a position below the bottom plate 4b of the circuit breaker room 4. FIG. 4 shows a plan view of the lock lever 8. The lock lever 8 has a pair of front and rear lever bodies 80, a base of which is fixed in the middle of the operation shaft 7.
80, and a contact piece 81 erected along the axial length direction of the operation shaft 7 at the distal end thereof.

FIG. 5 is a view taken along the line VV in FIG. This figure also shows a cross section of the bottom plate 4b of the circuit breaker room 4. As shown, the lever body 80 of the lock lever 8 is
An extension 80b is provided extending in a direction substantially perpendicular to one side of the base 80a fitted to the operation shaft 7, and the extension 80b
Is exposed to the inside of the circuit breaker chamber 4 through a long hole 4c formed in the bottom plate 4b.

As shown in FIG. 4, the elongated hole 4c is formed at a position corresponding to each of the pair of lever main bodies 80, 80 so as to have a width corresponding to their thickness. Is the bottom plate 4b
It is installed between the lever bodies 80 and 80 on the upper side. As a result, when no operating force is applied to the operating shaft 7, the lever body 80 moves as shown by a solid line in FIG.
Of the circuit breaker 40 located on the bottom plate 4b (shown by a broken line in the figure). They are facing each other at a distance.

In the state where the circuit breaker 40 is located above the contact piece 81, the grounding switch 6 is operated to ground.
When the operation shaft 7 is operated to rotate clockwise as described above, the lock lever 8 which is generated clockwise in response to the rotation operation.
The contact piece 81 at the tip of the lever body 80
Abuts the bottom of

FIG. 6 is a front sectional view of the circuit breaker chamber 4 showing this state. As shown in this figure, axles 45 of moving wheels provided on both sides of a cart 41 on which a circuit breaker 40 is mounted are mounted on the circuit breaker room 4.
Are fitted in guide rails 46, 46 having a U-shape as viewed from the front, which are fixed to the floor plate 4b, and the guide action of these guide rails 46, 46 allows the connection between the connection position and the disconnection position. Of the circuit breaker 40 can be performed without any positional displacement in the left and right and up and down directions. Therefore, the operating shaft 7 is rotated clockwise as described above, and the contact piece 81 is
Even after a further operating force is applied to the operating shaft 7 after abutting on the bottom surface of the axle 40, the abutting piece 81 pushes up the circuit breaker 40 so that the axle 45 Will be blocked by being pressed against
The grounding operation of the grounding switch 6 can be reliably prevented.

As shown in FIG. 3, the contact piece 81 is provided in the axial direction of the operating shaft 7, that is, in the direction of the movement path of the circuit breaker 40, of the circuit breaker 40 between the connection position and the disconnection position. The circuit breaker 40, which has a length L corresponding to the movement stroke and moves on the bottom plate 4b, reliably contacts the contact piece 81 as long as it is between the connection position and the disconnection position. The grounding operation of No. 6 is restricted.

On the other hand, when the circuit breaker 40 is pulled out to the disconnecting position, since the circuit breaker 40 is not located above the contact piece 81, the operation shaft 7 is similarly rotated. In response to this, the lock lever 8 swings within an allowable range defined by the long hole 4c as shown by a two-dot chain line in FIG. 5, and the lever body 80 and the contact piece 81 at the tip of the lever body 80 are shut off. The rotation of the operation shaft 7 is transmitted to the grounding switch 6 as described above, and the grounding switch 6 is grounded. The grounding switch 6 that has been grounded is operated.
Holds the grounding state by the spring force of the closing spring 65a, the swinging position of the lock lever 8 is maintained even after the rotation operation of the operation shaft 7 is stopped.

In such a grounded state, the lever body
The contact piece 81 at the tip of 80 is located at a position sufficiently higher than the position corresponding to the bottom surface of the circuit breaker 40, and in such a state, the circuit breaker 40 is connected as shown by the white arrow in FIG. When the push-in operation is performed to move the circuit breaker 40 to the position, the rear surface of the circuit breaker 40 comes into contact with the contact piece 81, and further push-in, that is, movement to the connection position is prevented. At this time, an impact force due to the collision with the circuit breaker 40 acts on the contact piece 81, and the acting direction is the axial direction of the operation shaft 7, and the impact force is generated by the support portion of the operation shaft 7. There is no danger that the durability of the grounding switch 6 will be impaired without being transmitted to the support shaft 66 on the rear side of the operation shaft 7 and the link mechanism connected thereto.

In the above embodiment, the circuit breaker
The operating shaft 7 is arranged at a position below the 40 moving routes, and the operating shaft 7
Although the configuration in which the lock lever 8 is provided has been described, the operating shaft 7 may be arranged at any position as long as the operating shaft 7 can face the moving path of the circuit breaker 4, for example, along the side wall of the circuit breaker chamber 40. Arrangements are possible. However, in this case, the breaker 40
It is necessary to change the form of the lock lever 8 so that reliable contact with this occurs according to the shape of the lock lever 8.

[0041]

As described above in detail, in the interlock device for electric equipment according to the first aspect of the present invention, the operation shaft for operating the grounding switch by turning around the axis is installed along the movement path of the circuit breaker. However, despite the simple configuration in which the lock lever is attached in the middle of the operation shaft, the movement of the circuit breaker to the connection position when the grounding switch is grounded, and the circuit breaker is pulled out to the disconnection position. In this state, the grounding operation of the grounding switch can be reliably prevented. Further, even when the circuit breaker collides with the lock lever as the circuit breaker moves to the connection position in a state where the ground switch is grounded, the impact force caused by the collision is borne by the support portion of the operation shaft. Thus, the reliability of the operation mechanism of the grounding switch can be improved without impairing the durability.

Further, in the interlock device for electric equipment according to the second aspect of the present invention, since the operating shaft is disposed below the moving path of the circuit breaker, the lock lever attached to the operating shaft is moved on the moving path. The circuit breaker can be reliably brought into contact with the lower surface thereof, and a reliable interlock operation can be performed.

Further, in the interlock device for electric equipment according to the third aspect of the present invention, the abutting piece having a length corresponding to the moving stroke of the circuit breaker is provided at the projecting end of the lock lever to the moving path of the circuit breaker. The contact piece is located on the movement path of the circuit breaker over the entire length between the disconnection position and the connection position, so that erroneous pushing operation of the circuit breaker is reliably prevented at the disconnection position. And the contact piece abuts against the circuit breaker at an intermediate position between the disconnection position and the connection position, thereby preventing erroneous grounding operation of the grounding switch. The present invention has excellent effects.

[Brief description of the drawings]

FIG. 1 is a side sectional view schematically showing the entire configuration of a closed switchboard provided with an interlock device according to the present invention.

FIG. 2 is an operation explanatory view of the interlock device according to the present invention.

FIG. 3 is an explanatory diagram of an operation of the interlock device according to the present invention.

FIG. 4 is a plan view showing a connection relationship between an operation shaft and a support shaft.

FIG. 5 is a view taken along line VV of FIG. 4;

FIG. 6 is a front sectional view of the circuit breaker room showing a state in which the grounding operation of the grounding switch is restricted.

[Explanation of symbols]

3 Cable room, 4 Breaker room, 6 Ground switch, 7
Operating shaft, 8 lock lever, 20 busbar side branch conductor, 30
Load side conductor, 40 breakers, 81 contact pieces.

Claims (3)

[Claims] 1. A method according to claim 1, further comprising moving between a connection position and a disconnection position along a predetermined path to connect / disconnect a bus-side branch conductor connected to a common bus and a load-side conductor connected to a power transmission cable to a load. A circuit breaker, a grounding switch for grounding or releasing the load side conductor, and a erection along the direction of movement facing the movement path of the circuit breaker, and the grounding switch is rotated around an axis. And an operation shaft mounted on the operation shaft for projecting into the movement path according to the rotation of the operation shaft for the grounding operation, and the rotation of the operation shaft for the ground release operation A lock lever that is disengaged from the movement path in accordance with the above.When the circuit breaker is at the connection position, the rotation of the operation shaft is restrained by abutment of a part of the circuit breaker and the lock lever. Prohibit grounding operation of the earthing switch, and make sure that the earthing switch Wherein when the circuit breaker is in contact with the lock lever, the circuit breaker is prohibited from moving to the connection position. 2. The interlock device according to claim 2, wherein the operating shaft is disposed at a position below a movement path of the circuit breaker. 3. The lock lever has an abutment at a protruding end of the circuit breaker on a movement path, the length being equal to a movement stroke of the circuit breaker between the connection position and the disconnection position along the movement path. 3. The interlock device for an electrical installation according to claim 1, further comprising a piece.