JP2598467Y2 - Lock mechanism for gas switch when gas pressure drops - Google Patents

Description

[Detailed description of the invention]

[0001]

The present invention relates to an SOG that automatically opens a movable electrode when a ground fault occurs and disables opening and closing of the movable electrode when a short circuit occurs.
More particularly, the present invention relates to a lock mechanism for a gas switch in which an arc-extinguishing gas is sealed at a predetermined pressure in a switch when the gas pressure drops.

[0002]

2. Description of the Related Art Conventionally, there has been known a switch provided with an automatic opening operation mechanism for automatically opening a movable electrode when a ground fault occurs in a power line. In this switch, when a predetermined signal is output from the ground fault relay, the trip coil is operated based on the signal, and the trigger lever is switched from the standby position to the operating position. And
The closed state of the link mechanism is broken, and the movable electrode automatically opens.

Further, an arc-extinguishing gas such as sulfur hexafluoride gas is sealed at a predetermined pressure in the gas-filled switch to improve electrical performance such as dielectric strength in the switch case. The switch is provided with a gas pressure reduction lock mechanism that locks the switching operation mechanism when the gas pressure drops below a predetermined pressure. This gas pressure drop lock mechanism
When the gas pressure decreases, the electrical performance such as withstand voltage in the switch case filled with gas decreases,
It is provided for safety. The switch is provided with a lock mechanism for the automatic opening operation mechanism described above, in addition to a lock mechanism for locking the manual opening operation. This automatic opening operation mechanism includes detection means for detecting a decrease in gas pressure, and a microswitch for opening the trip coil circuit by the detection means. And
When the gas pressure decreases, the circuit for driving the trip coil is cut off by the microswitch, and the trip coil does not operate. Therefore, the automatic opening operation of the movable electrode is locked. Since the lock mechanism of the automatic opening operation mechanism is electrically configured, there is room for improvement in terms of reliability, and it is desired to add a mechanical lock mechanism.

[0004]

However, if the lock mechanism for the automatic opening operation mechanism is mechanically constructed, the structure becomes complicated and it is not easy to reduce the size of the entire switch. further,
The trip coil that performs the automatic opening operation is provided separately from the lock mechanism for the manual opening operation, and it is difficult to operate the locking mechanism for the automatic opening operation and the locking mechanism for the manual opening operation at the same time. There was a problem that is.

The present invention has been made in view of the problems existing in the prior art as described above. The purpose of the present invention is to make the locking operation compact when the pressure is reduced. It is an object of the present invention to provide a highly reliable locking mechanism for a gas switch when the gas pressure drops.

[0006]

In order to solve the above-mentioned problems, the present invention provides a gas pressure detecting mechanism for detecting when a gas sealed in a switch case drops to a predetermined pressure, and the gas pressure detecting mechanism. A first lock mechanism that locks operation of an open / close operation mechanism in the switch case by moving a first lock member provided in the switch case to a lock position in response to a detection operation of the pressure detection mechanism. Between the trip coil that automatically opens the movable electrode based on the trip signal and the automatic opening operation mechanism, and between a lock position that prevents movement of the plunger of the trip coil and an unlock position that allows movement. A second lock mechanism having a movable second lock member; and a transmission means for transmitting a lock operation of the first lock member to the second lock member. It has as its gist.

[0007]

In the present invention thus constructed, the gas pressure detecting mechanism detects when the gas sealed in the switch case drops to a predetermined pressure. In response to the detection operation of the gas pressure detection mechanism, the first lock mechanism moves the first lock member provided in the switch case to the lock position. The operation of the switching operation mechanism in the switch case is locked by the first lock member. The lock operation of the first lock member is transmitted to the second lock member by the transmission means, and the second lock member is moved to the lock position where the plunger of the trip coil is prevented from moving.
For this reason, the operation of the automatic opening operation mechanism is prevented.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is embodied in a high pressure gas switch for an underground line will be described below with reference to the drawings.

As shown in FIGS. 1 and 2, a gas switch 1
The switch case 2 is sealed in a rectangular box shape, and an arc-extinguishing gas (sulfur hexafluoride gas in this embodiment) is sealed in a switch chamber 3 inside the switch case 2 at a predetermined pressure. A power supply-side bushing 4 and a load-side bushing 5 whose inner ends protrude into the switch chamber 3 are fixed to the upper and lower surfaces of the switch case 2 that face each other.

A conductive member 6 protrudes from an inner end of the power supply side bushing 4, and a fixed electrode 7 constituting an opening / closing portion is further attached to the conductive member 6. Similarly, a conductive member 8 protrudes from the inner end of the load-side bushing 5. Further, a movable electrode 9 constituting an opening / closing section together with the fixed electrode 7 is attached rotatably around the conductive member 8,
It is arranged so as to be able to contact the fixed electrode 7.

An open / close operation shaft 10 is rotatably supported on the front side of the switch case 2.
A manual opening / closing operation lever (not shown) is detachable at the outer end of the. A swing lever 12 is externally fitted and fixed to the inner end of the opening / closing operation shaft 10, and the swing lever 12 is connected to a lever 15 of an opening / closing link mechanism 14 via a direction conversion link 13. Opening / closing operation shaft 10, swing lever 1
2. The opening / closing operation mechanism is constituted by the direction changing link 13 and the opening / closing link mechanism 14. Further, the tip of the link 16 of the opening / closing link mechanism 14 is rotatably connected to the center of the movable electrode 9, and the movable electrode 9 is rotated by the linear movement of the link 16. That is, when the opening / closing drive lever is rotated clockwise or counterclockwise in FIG. 1, the swing of the swing lever 12 is converted by the direction conversion link 13 into a vertical movement (arrow A) in FIG. The end of the lever 15 of the opening / closing link mechanism 14 is moved up and down. By this vertical movement, the opening and closing link mechanism 1
4 rotates the movable electrode 9 (in the direction of the arrow B in the figure). When the movable electrode 9 is rotated in the direction of the fixed electrode, the fixed electrode 7 receives the tip of the movable electrode 9 and conducts between the power supply side and the load side. Conversely, when the movable electrode 9 is turned in a direction to separate from the fixed electrode 7, the movable electrode 9 separates from the fixed electrode 7, and the connection between the power supply side and the load side is released.

Further, on the front side of the switch case 2, an on / off display section 17 and a gas filling section 18 are provided. The turning shaft 19 of the ON / OFF display unit 17 is rotatably supported by the switch case 2, and a pointer 20 is fixed to the outer end. The inner end of the rotating shaft 19 is connected to the opening / closing operation shaft 10 by a connection mechanism (not shown), and the indication of “in” and “off” of the hands 20 is displayed in conjunction with the opening / closing operation shaft 10. It can be switched. The gas filling part 18 is
In order to enclose the arc-extinguishing gas into the opening / closing chamber 3 from here, an enclosing hole 21 for inserting a gas sealing jig to be described later is provided, and the enclosing plug 60 is always inserted and the lid 22 is externally fitted. .

As shown in FIG. 3, a bellows 25 is attached to the upper outer peripheral surface of the switch case 2 so as to be located outside the switch case 2. A cap 26 is fitted around the outer circumference of the bellows 25, and the switch case 2 is inserted into an insertion hole formed in a flange portion 27 of the cap 26.
The cap 28 is fixedly fastened by a nut 28a. Bellows 25
A bellows shaft 29, which constitutes a gas pressure detecting mechanism, projects upward from the center of the inner bottom wall of the bellows 25. When the gas pressure in the opening / closing chamber 3 is equal to or higher than a predetermined pressure, the top of the bellows shaft 29 protrudes upward through a through-hole above the cap 26. When the gas pressure in the switching chamber 3 decreases, the bellows 25 contracts, and accordingly, the bellows shaft 29 also moves toward the switch case 2.

The rotation shaft 32 is rotatably fitted through an O-ring 35 to a cylindrical portion 34 protruding from the upper part of the switch case 2. The O-ring 35 keeps the open / close chamber 3 airtight. The latch 31 is fixed to the rotation shaft 32 by a bolt 36, and is integrally rotatable together with the rotation shaft 32. A coil spring 33 is provided on the rotating shaft 32.
Is wound, and one end thereof is locked by the latch 31, so that the latch 31 is urged in the engagement direction (upward direction orthogonal to the paper surface in FIG. 3). Further, the tip of the latch 31 is locked on the upper part of the bellows shaft 29, so that the rotation of the rotation shaft 32 is prevented. A cover 37 is provided so as to cover the periphery of the gas pressure detection mechanism. The cover 37 is detachably attached to the switch case 2 with bolts 30 to protect the gas pressure detection mechanism.

The inner end face of the rotating shaft 32 faces the opening / closing chamber 3, and a lever 38 is formed on the inner end face. The lever 38 has a pressing projection 39 projecting from a position away from the center of the shaft. Due to this eccentricity, when the rotation shaft 32 rotates, the pressing protrusion 39 moves its position toward the front of the drawing.

A channel-shaped bracket 46 is fixed to the inner surface of the switch case 2 below the bellows 25 in the switch room 3. Also, the bracket 46
A plate-shaped stopper 54 is fixed to the switch case 2 in parallel with the switch. The lock pin 45 as a first lock member constituting the lock mechanism is arranged such that the axis of the lock pin 45 is coaxial with the sealing hole 21. That is, the lock pin 45 is provided with a guide pin 47 protruding from the lower portion of the bracket 46 toward the sealing hole 21 side.
And is movable between a locked position shown by a two-dot chain line protruding leftward in the figure and an unlocked position close to the bracket 46. The lock pin 45 has a flange 49 formed at the center thereof.
A coil spring 48 is disposed between the coil spring 48 and the bracket 46. The spring 48 urges the lock pin 45 leftward in FIG.

When the lock pin 45 is protruded, its tip protrudes to the left in FIG. 3 through a through hole at the lower end of the stopper 54, and the flange portion 49
, The lock position is always kept at a fixed position. The locked position is the position of the swing lever 12.
Is located on the rotation locus of.

As shown in FIG. 4, the center of the latch lever 50 is supported by a shaft 51 provided between the bracket 46 and the stopper 54. The latch lever 50 is rotatably mounted on the bracket 46 about the shaft 51. Is being worn. Latch lever 5
The first end 50a of the lock pin 45 is
The lock pin 45 is held at the unlock position by being locked to the lock pin 9. Second end 50 of latch lever 50
b is urged by a coil spring 55 having one end fixed to the switch case 2 in a direction to release the locking of the flange portion 49. When the gas pressure in the opening / closing chamber 3 is equal to or higher than a predetermined value, the second protrusion 50 is pressed by the pressing projection 39.
b is locked and its movement is prevented. Therefore, the locking of the flange portion 49 is maintained.

As shown in FIG. 3, a limit switch 52 is further attached to the bracket 46. The lever 53 of the limit switch 52 can come into contact with the flange portion 49 of the lock pin 45 located at the unlock position, and when the lock pin 45 is at the unlock position, the limit switch 52 is turned on and the lock pin 45 is turned on. It turns off when it is in the lock position. Therefore, the position of the lock pin 45 is converted into "ON" and "OFF" of the electric signal by the limit switch 52 and used for display or other control.

As shown in FIGS. 5 and 6, a trip coil 76 is mounted in the switch case 2 by a bracket (not shown). The trip coil 76 has a plunger 77 therein. The plunger 77 is attracted to the main body when excited, and protrudes from the main body when not excited. The tip of the plunger 77 is formed in a forked shape, and one end of the trigger lever 80 is supported by the shaft 78 with respect to the forked portion. Both ends of the shaft 78 project from the forked portion. The trigger lever 80 is rotatably supported via a shaft 79 on a support plate 80a fixed to the switch case 2. The trigger lever 80 is
It is movable between a standby position indicated by a solid line in FIG. 5 and an operation position indicated by a two-dot chain line, and is always held at the standby position by the urging force of a spring 81 wound around a shaft 79. In the standby position, the other end of the trigger lever 80 is locked with a link mechanism 82 which is a part of an automatic opening operation mechanism for operating a movable electrode (not shown). With this locking, the link mechanism 82 can be held in the closed state, and the circuit is held in the connected state. On the other hand, when the trip coil 76 is operated and the trigger lever 80 rotates and moves to the operating position, the locking between the trigger lever 80 and the link mechanism 82 is released. By this unlocking, the closed state of the link mechanism 82 is broken, and the movable electrode is automatically opened.

A lock lever 83, which is a second lock member, is rotatably connected to a lower portion of the trip coil 76 about a shaft 84 supported between support plates 80a.
The lock lever 83 is movable between an unlock position indicated by a solid line in FIG. 5 and a lock position indicated by a two-dot chain line. A concave portion 85 is formed at one end of the lock lever 83, and when the lock lever 83 moves to the locked position, the concave portion 85 is formed.
Can be engaged with the shaft 78 at the tip of the plunger 77. That is, in the locked position, both ends of the shaft 78 abut on the lock lever 83, and the plunger 77 is prevented from being sucked into the main body.

The lock lever 83 is connected to the lock pin 45 via a release 86 as a transmission means. The release 86 includes a wire 87 and the wire 87.
, And a wire 87 is slidably disposed in the flexible tube 88. Both ends of the flexible tube 88 are brackets 89a,
89b is fixedly fastened to the switch case 2 so that only the wire 87 can move. Release 86
One end of the wire 87 is connected to one end of the lock lever 83, and a spring 90 is disposed around the wire 87 between the bracket 89a on the lock lever side and the lock lever 83. The lock lever 83 is urged by the spring 90 toward the unlock position. On the other hand, wire 87
Is routed to the bottom in the switch case 2 and the wire 87
Is fixed to a locking portion 91 provided on the flange portion 49 of the lock pin 45. Therefore, the lock pin 45
Is moved to the axial locking position, one end of the lock lever 83 is pulled by the wire 87 against the urging force of the spring 90. Then, the lock lever 83 rotates counterclockwise in FIG. 5 about the shaft 84 and is switched to the lock position. Conversely, when the lock pin 45 is moved in the direction of storing the coil spring 48, the lock lever 83 returns to the unlock position by the stored power of the spring 90.

Next, the operation of the gas switch 1 constructed as described above for the locking operation when the gas pressure is reduced will be described. Now, in this gas switch 1, when the gas pressure in the switch case 2 is maintained at a predetermined value or more, as shown in FIG. 3, the bellows 25 of the gas pressure detecting mechanism expands due to the gas pressure. The latch 31 is locked on the bellows shaft 29. Further, as shown in FIG.
The pressing projection 39 is held at a blocking position for blocking the movement of the second end 50b of the latch lever 50, and the lock pin 45 is locked at the first end 50a of the latch lever 50 with the flange 49, and is at the unlock position. Is held.

In this state, when the gas pressure in the gas switch 1 falls below a predetermined value, the bellows 25 of the gas pressure detecting mechanism contracts, and a part of the bellows shaft 29 is moved into the switching chamber 3, The latch between the latch 31 and the bellows shaft 29 is released. Then, the rotating shaft 32 is rotated by the urging force of the spring 33, and the pressing protrusion 39 moves from the blocking position in the direction indicated by the arrow C in FIG. Since the second end 50b of the latch lever 50 is urged by the coil spring 55, when the pressing projection 39 moves, the latch lever 50 similarly rotates clockwise about the shaft 51, The locking of the flange portion 49 is released. When this locking is released, the lock pin 45 is
Due to the biasing force of 8, the lever moves to the position shown by the two-dot chain line in FIGS.
This position is determined by the flange portion 49 of the lock pin 45 contacting the stopper 54. Therefore,
The swing of the swing lever 12 is prevented by the lock pin 45, and the opening and closing operation of the switch 1 is locked.

With the movement of the lock pin 45, the locking part 91 provided on the flange part 49 also moves, and the wire 8
7 in the same direction. With this pulling, the wire 87
One end of the lock lever 83 connected to the other end of the
5 around the shaft 84 in the counterclockwise direction in FIG. Accordingly, the lock lever 83 is moved to the lock position as shown in FIG. 7, and the plunger 77 is engaged with the concave portion 85 of the lock lever 83. Then, the shaft 78 comes into contact with the lock lever 83, and the plunger 77 is prevented from being sucked into the main body. Therefore, the automatic opening operation mechanism is also locked.

As described in detail above, since the lock pin 45 and the lock lever 83 are connected by the release 86, the lock lever 83 can be moved to the lock position with the operation of the lock pin 45. That is, the lock for the manual release and the lock for the automatic release operation mechanism can be performed by a single operation with a very simple configuration. Further, not only the electric locking means but also the mechanical locking mechanism is provided, so that the locking operation is performed very reliably, and the reliability can be improved.

It should be noted that the present invention is not limited to the above embodiment, and may be appropriately changed as follows without departing from the spirit of the present invention. (1) In the above embodiment, the bellows 25 and the bellows shaft 29 are used as the gas pressure detecting mechanism. Instead, the gas pressure detecting mechanism is constituted by a diaphragm and a shaft protruding from the center of the diaphragm. Alternatively, the latch may be locked by a shaft.

(2) In the above embodiment, the release 86 is used as the transmission means, but a simple wire may be used to connect the lock pin 45 and the lock lever 83 via a roller.

[0029]

[Effect of the Invention] As described in detail above, according to the present invention,
An excellent effect is provided that it is possible to provide a compact and highly reliable locking mechanism for the gas switch when the gas pressure drops, which reliably performs the locking operation when the pressure drops.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of a gas switch provided with a lock mechanism at the time of a decrease in gas pressure according to the present invention.

FIG. 2 is a sectional view showing the gas switch of FIG. 1;

FIG. 3 is an enlarged sectional view showing a pressure detection mechanism and a lock mechanism of the gas switch.

FIG. 4 is a cross-sectional view taken along line AA of FIG.

FIG. 5 is a front view showing a main part of a gas switch provided with a lock mechanism when the gas pressure drops.

FIG. 6 is a cross-sectional view showing the automatic opening / closing operation mechanism of the gas switch shown in FIG. 5 in an unlocked state.

FIG. 7 is a cross-sectional view showing a state in which the automatic opening operation mechanism of the gas switch shown in FIG. 5 is locked.

[Explanation of symbols]

2 ... switch case, 10 ... opening and closing operation shaft, 12 ... swing lever, 13 ... direction conversion link, (constituting opening and closing operation mechanism) 21 ... sealing hole, 25 ... bellows, 29 ... bellows shaft,
(Constituting the detection mechanism) 45... (A first lock member) lock pin, 76.
Trip coil 77, plunger 83, lock lever (which is a second lock member constituting a lock mechanism),
86 Release (which is a transmission means).

Claims (1)

(57) [Scope of request for utility model registration] 1. A gas pressure detecting mechanism for detecting when a gas sealed in a switch case drops to a predetermined pressure, and provided in the switch case in response to a detecting operation of the gas pressure detecting mechanism. A first lock mechanism that locks the operation of an opening / closing operation mechanism in the switch case by moving the first lock member to a lock position; and a trip coil that automatically opens a movable electrode based on a trip signal. A second lock mechanism provided between the opening operation mechanisms and having a second lock member movable between a lock position for preventing movement of the plunger of the trip coil and an unlock position for allowing movement; A transmission mechanism for transmitting a locking operation of the first locking member to the second locking member, wherein the locking mechanism of the gas switch when the gas pressure is reduced is provided.