JPH09265877A - Displaying method of lowered gas pressure of gas-blast load-break switch and gas-blast load break switch - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable preparation for replacement in advance by displaying that a gas-blast load-break switch will be inoperable in the near future when the gas pressure is lowered. SOLUTION: When the gas pressure in a case is within a specified pressure range, an engagement adjustment member 23 and an engagement recess 320 of a rotational- movement plate 323 are engaged with each other, and a normal display port 340c can be visualized from a display window. When the gas pressure is lowered, a bellows inflates, the engagement state of the engagement adjustment member 23 and the rotational movement plate 323 is released, the engagement adjustment member 23 passes through a pressure reduction prediction guide part 321 and is engaged with a prediction state engagement part 330, and a prediction display port 340b can be visualized. This indicates that a gas-blast load-break switch will be inoperable in the near future. Therefore, preparation for replacing the gas-blast load-break switch can be done in advance. If the gas pressure is further lowered, the bellows inflates more, the engagement state with the engagement adjustment member 23 and the rotational movement plate 323 is released, the pressure reduction display port can be visualized, and an operation handle is inoperable.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for indicating a decrease in gas pressure of a gas switch and a gas switch, and more particularly to a lock for locking an operating handle when the pressure of gas enclosed in the switch decreases. The present invention relates to a device in which this reduced pressure state is displayed before the operating pressure is reached.

[0002]

2. Description of the Related Art A gas switch in which a gas such as SF6 gas is enclosed in a switch to extinguish an arc generated when a contact is opened and to maintain insulation performance is disclosed in, for example, Japanese Unexamined Patent Publication (Kokai) No.
-363826, Japanese Utility Model Publication No. 7-20010,
JP-B-63-25629, JP-B-62-4540
No. 0, etc. In the gas switch,
If the pressure of the enclosed gas decreases, the above performance cannot be obtained. Therefore, when the gas pressure drops below a predetermined value in these gas switches, it is detected and displayed by an audible signal and / or a visible signal using electrical or mechanical means. There is provided a device for locking the operation handle of the gas switch so that it cannot be operated and for locking the electric circuit of the VTC tripping operation.

[0003]

However, the conventional gas switch described above has the following problems. In other words, in the conventional gas switch, from the viewpoint of SF6 gas characteristics that the gas pressure decreases due to the temperature decrease and the safety factor, the operation handle should be operated at a gas pressure value higher than the gas pressure value that requires locking the operation handle. Locking control is performed to ensure safety performance.

In the conventional control of the gas switch, only the operation handle is locked or not locked, and therefore it cannot be determined how much gas leakage has progressed until the operation handle is locked. Then, one day, the operation handle suddenly locks. From the viewpoint of maintenance of the gas switch, if it is known how much gas leakage of the gas switch is progressing, for example, if the gas pressure is between the specified pressure and the lock operating pressure at which the operating handle locks, next time Since you can take measures such as inspection and switch replacement, the operating handle suddenly locks one day,
It can be used with peace of mind without suffering damage such as inoperability of the switch. However, the conventional gas switch does not have such a function, and after the locked state of the operation handle occurs,
There was a problem of being overwhelmed by the measures.

Therefore, an object of the present invention is that the pressure of the gas enclosed in the switch falls between the specified pressure and the lock operating pressure before the pressure reaches the lock operating pressure for locking the operating handle. It is an object of the present invention to provide a method for displaying a decrease in gas pressure of a gas switch and a gas switch which are configured to display the above.

[0006]

The means taken to achieve the above object and solve the problems are as follows. According to the first aspect of the invention, when the pressure of the gas enclosed in the gas switch is lowered to the lock operating pressure for locking the operation handle, this is detected, and this state is detected by an audible signal and / or a visible signal. A signal is displayed and the operating handle is locked, and it is detected that the pressure of the enclosed gas is between the specified pressure and the lock operating pressure before the pressure of the enclosed gas drops to the lock operating pressure. However, it is a method of displaying a decrease in gas pressure of the gas switch, including the step of displaying this state by an audible signal and / or a visible signal.

According to the second aspect of the invention, an actuating means which is actuated when the pressure of the gas enclosed in the gas switch is lower than a specified pressure, and an interlocking means for transmitting the movement of the actuating means to another. A pressure detecting device comprising: a pressure reducing device constituted by means for displaying the state of the pressure of the enclosed gas by an audible signal and / or a visual signal; A gas switch provided with a lock device for transmitting the movement of the interlocking device to the locking device via the transmitting device to lock the operation handle, wherein the decompression display device has a sealed gas pressure of a specified pressure. A gas switch, including means for indicating that it is between lock operating pressures.

A bellows is usually used as an actuating means which is actuated when the pressure of the enclosed gas falls below a specified pressure, but is not limited to this, and for example, a Bourdon tube, a diaphragm, etc. It is also possible to use the one of

When the pressure of the gas filled in the working switch becomes lower than the specified pressure, the operating means is activated, and the pressure of the gas is displayed on the decompression display device via the interlocking means and the transmitting means. Between the two is indicated by an audible signal and / or a visible signal. When the pressure of the enclosed gas further decreases, the operating means continues to operate, and when the pressure decreases to the lock operating pressure, the decompression display device indicates by an audible signal and / or a visual signal that the gas pressure has decreased to the lock operating pressure. At the same time, the locking device operates to lock the operation handle.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail based on the embodiments shown in the drawings. 1 is a front view showing the entire gas switch according to the present invention, FIG. 2 is a side view of the gas switch shown in FIG. 1, FIG. 3 is a sectional explanatory view of a pressure detection device and a decompression display device, and FIG. Explanatory diagram showing the relationship between the pressure detection device and the decompression display device with the display cover removed, FIG.
6 is a cross-sectional view taken along line AA of the operating member shown in FIG.
FIG. 9 is a sectional view showing another embodiment of the actuating member shown in FIG. 5. 7 is a partially cutaway explanatory view of the decompression display device and the lock device of the operation handle, FIG. 8 is a schematic explanatory view seen from the direction C in FIG. 7, and FIG. 9 is a schematic explanatory diagram of a main part seen from the direction D in FIG. Is. FIG. 10 is an explanatory diagram showing a correlation between movements of the operating member and the interlocking plate in accordance with a change in gas pressure in the gas switch, showing a prescribed pressure state, FIG. 11 is an explanatory diagram showing a preliminary state of pressure reduction, and FIG. It is explanatory drawing which shows the locked state of an operating handle.

Reference numeral 1 denotes a gas switch. The gas switch 1 includes a case 10. Side wall 1 of case 10
An operation handle 11 is provided so as to project outward from the position 2. The operation handle 11 is for opening and closing the contact of the switch, and the stopper 11 is attached to the shaft S penetrating the case 10.
The operation handle 11 and the stopper 110 are mechanically restrained and perform the same movement. In FIG. 7, the operation handle 11 is in a position where the switch is in the on state, and in the off state, it is in a state rotated 90 ° counterclockwise in the figure.

The gas switch 1 includes a pressure detecting device 2, a pressure reducing display device 3, and a lock device 4. Decompression display device 3
The protrusion of the lock device 4 is shorter than the protrusion of the operation handle 11. Next, the pressure detection device 2, the reduced pressure display device 3, and the lock device 4 will be described.

(Pressure Sensing Device 2) Referring to FIG. The pressure detecting device 2 is installed on the side wall 12 in an airtight state by a known means. The pressure detection device 2 includes a bellows 21 and
It has an operating rod 22 operated by this. The operating rod 22 is provided with a base 24 at the base end. A base plate 27 and a hollow bearing 25 are screwed to the side wall 12 with a nut 28, and the bellows flange 210 is attached to the base end of the bearing 25.
Adheres to the side wall 12. Between the bellows flange 210 and the base 24, a bellows 21 and an urging spring 26 for maintaining a balance at a predetermined position at a predetermined pressure value are disposed.

The operating rod 22 is inserted through the bearing 25, and the tip end side thereof is located outside the case 10. The base 24 at the base end is located inside the case 10. An engagement adjusting member 23 is screwed to the distal end. The engagement adjusting member 23 is for correcting the moving amount of the operating rod 22, is for correcting the variation of parts and adjusting the detection value, and can be finely adjusted by the screw structure.

When the gas pressure in the case 10 becomes low, the bellows 21 swells and the base 24 moves to the right. That is, the operating rod 22 moves according to the expansion and contraction of the bellows 21. To attach the pressure detection device 2 to the case 10, a screw is provided on the small diameter portion of the bellows flange 210, and the board 27 is sandwiched between
It is fixed by a nut 28. An O-ring 29 is arranged on the contact surface between the case 10 and the bellows flange 210 to keep airtightness.

The substrate 27 has a display cover 3 which will be described later.
The support 270 for fixing the 3 is fixed by caulking at two places. The board 27 is attached to the case 10 at two positions, one of which is the nut 28. The other is a stud bolt 101 welded to the case 10 and a nut 1
02 is fixed by tightening it through a spring washer.

(Decompression Display Device 3) The decompression display device 3 is installed outside the side wall 12, and the pressure detection device 2 displays the pressure state of the gas sealed in the case 10. The decompression display device 3 has an operating member 32. The actuating member 32 has a cylindrical rotating shaft 322 and a rotating plate 323 integrally provided on the rotating shaft 322. The rotating shaft 322 has an engaging portion 31 having a fitting irregularity at the tip.
It has 0. The rotating shaft 322 is fitted to the operating shaft 31 fixed to the center of the substrate 27 by caulking, and is rotatably mounted. The rotating plate 323 has an engaging portion recess 320 that engages with the engagement adjusting member 23 screwed to the tip of the operating rod 22.

On the bellows 21 side of the operating member 32, there is formed a depressurization advance guide part 321 extending from the engagement recess 320 to the advance notice engagement part 330 (see FIG. 4). The decompression notice guide portion 321 can be formed by grinding one plate body as shown in FIG. 5, or as shown in FIG. 6, two or more plate bodies are superposed to form a decompression notice on the bellows 21 side. Guide 32
It can also be formed by arranging a plate body in which 1 is cut out.

Referring to FIG. Rotating plate 3 as described above
The reference numeral 23 designates an engagement recess 320 and a decompression notice guide section 32 following the engagement recess 320.
One. The actuating member 32 is biased in the rotational direction by a spring (not shown). In the normal state, the engagement adjusting member 23 of the operating rod 22 and the engagement recess 320 are engaged and stopped.

When the gas in the case 10 is depressurized, the operating rod 22 moves to the right in FIG. Therefore, the operating member 32 is released from the engaged state and rotates counterclockwise integrally with the rotating shaft 322 along the plane parallel to the side wall 12.
Along with this, the engagement adjusting member 23 is moved to
1 is moved and the engagement is stopped at the notice state engagement portion 330. 5
Reference numeral 00 is a microswitch disposed near the actuating member 32, and has a lever 520.

The decompression display device 3 has a bottomed cylindrical display cover 33. The display cover 33 covers at least the operating shaft 31 and the operating member 32. An interlocking plate shaft 36 is provided so as to penetrate the display cover 33 (see FIG. 3). An engaging portion 360, which is formed by fitting irregularities, engages with the engaging portion 310 at the tip of the rotating shaft 322 at the base end of the interlocking plate shaft 36.
Is formed. Therefore, the engaging portion 310 and the engaging portion 360
When the rotary shaft 322 rotates in the fitted state, the interlocking plate shaft 36 also rotates.

Referring to FIG. The interlocking plate 34 is attached to the tip end side of the interlocking plate shaft 36. The interlocking plate 34 has an elongated display plate 340, which is bent at two places with an obtuse angle and has three display portions formed at its tip (the display plate is omitted in FIG. 3). The display plate 340 has a decompression display portion 340 colored in red or the like from the base side to the tip side.
a, a notice display portion 340b colored in yellow or the like, and a normal display portion 340c colored in green or the like.

The interlocking plate 34 is provided with an engaging portion 341 which engages with the interlocking plate engaging portion 42, which will be described later, and an operating projection 342. A notch 343 that does not engage with the interlocking plate engaging portion 42 is formed between the engaging portion 341 and the operating protrusion 342. The interlocking plate 34 rotates integrally with the interlocking plate shaft 36 along a plane parallel to the side wall 12. Reference numeral 5 is a protective cover that covers the display cover 33, and a display window 50 is provided on the lower surface so as to be viewed from below.

(Locking device 4) Referring to FIG. The locking device 4 is installed outside the side wall 12 of the case 10,
The operation handle 11 is locked. The lock device 4 includes a trip claw 40 and a plate-like lock member 45 formed in a substantially “J” shape. The lock member 45 is a lock body 45.
0 and the lock body 450 are integrally provided with a pressing body 452.

The trip claw 40 is fixed by a screw to the tip of a pivot 41 provided through the side wall 12. Therefore,
The pivot 41 rotates with the trip claw 40. As shown in FIG. 8, a boss 410 penetrating the case 10 is fixed with a nut. The pivot 41 is inserted through the boss 410.

A support frame 44 is fixed to the boss 410 with a nut. The side wall 12 is provided with a support plate 37 having a square hole 370 formed by welding. An engagement notch 44 a is provided at the tip of the support frame 44. The engagement notch 44a and the support plate 37 are fitted, and the support frame 44 is fastened to the boss 410 with a nut to perform positioning and rotation prevention. A lock body 450 is attached to the square hole 370 so as to penetrate therethrough.

The trip claw 40 is provided with an interlocking plate engaging portion 42 which engages with the engaging portion 341 of the interlocking plate 34. On the side opposite to the interlocking plate engaging portion 42, a contact portion 42a is provided.
Further, a stopper pin 451 that engages with the tripping claw 40 is formed on the lock body 450. Tripping nail 4
0 is a stopper pin 4 protruding from the lock member 45.
A lock member engaging portion 43 that engages with 51 is provided. In the normal state of the trip claw 40, the engagement portion 341 and the interlocking plate engagement portion 42 are engaged with each other, and the stopper pin 451 and the lock member engagement portion 43 are engaged with each other, so that the lock member 45 is in a stopped state. .

The lock member 45 is biased toward the operation handle 11 by a spring 48. Lock member 45
Is locked by the disengagement of the stopper pin 451 and the lock member engaging portion 43 to move in parallel with the side wall 12 and the operation handle 11. 47 is an O-ring for keeping the gas container airtight.

One end of a wire rope 52 is fixed to the pivot 41 by a screw or the like. The other end of the wire rope 52 passes through the buffer plate 51 and is fixed to the lever tip of the micro switch 501. In the present embodiment, the contacts of the microswitch 501 are connected in series to the trip coil for shutting off the switch in the event of a ground fault or short circuit, so that the voltage of the trip coil cannot be applied during depressurization. . It is also possible to take out the alarm contact at the time of pressure reduction in the same manner.

Reference numeral 53 is a unit frame in which a mechanical unit such as on / off operation and pulling out is attached to the case 10. The wire rope 52 is passed through a hole formed in the unit frame 53. Therefore, only a very small space of the unit is required, and the limited space can be effectively used.

Operation The operation will be described mainly with reference to FIGS. 3, 7, and 10 to 12. When the gas pressure in the case 10 is within the specified pressure range, the engagement adjusting member 23 and the engagement recess 320 of the rotating plate 323 are provided.
And are in engagement. At this time, the normal display portion 340c can be seen from the display window 50, and it can be visually recognized from the outside that the pressure of the gas sealed in the case 10 is within the specified pressure range.

When the gas pressure in the case 10 decreases, the bellows 21 expands. As the bellows 21 expands, the operating rod 22 moves to the right in FIG.
3 and the engaging recess 320 of the rotating plate 323 are released. When the engagement state is released, the engagement adjustment member 23 passes through the pressure reduction advance notice guide portion 321 and is engaged with the advance notice state engagement portion 330. At this time, the notice window 340b is displayed from the display window 50.
Can be seen, the pressure of the gas enclosed in the case 10 can be visually confirmed to be between the specified pressure and the lock operating pressure, and in the near future, the operation handle 11 of the gas switch 1 will be locked and the opening / closing operation will not be possible. You can display things in advance. Therefore, before that, replace the gas switch 1, etc.
It will be possible to make preparations and make countermeasures in advance in advance.

When the gas pressure in the case 10 further decreases, the bellows 21 further expands. As the bellows 21 expands, the operating rod 22 moves further to the right in FIG.
The engagement adjustment member 23 and the advance notice state engagement portion 33 of the rotating plate 323.
The engagement state with 0 is released. At this time, the decompression display portion 340a can be seen from the display window 50, and it can be visually recognized that the pressure of the enclosed gas has dropped below the lock operating pressure.

Engagement adjustment member 23 and advance notice engagement section 3
When the engagement state with 30 is released, the operating member 32 and the interlocking plate 34 rotate counterclockwise. When the interlocking plate 34 rotates counterclockwise, the operating protrusion 342 moves the interlocking plate engaging portion 42.
Press. When the operating projection 342 pushes the interlocking plate engaging portion 42, the disengagement claw 40 rotates clockwise, and the stopper pin 451
And the lock member engaging portion 43 are disengaged.

The lock member 45 moves to the right in the figure by the release. Therefore, the lock body 450 moves to the right and locks the operation handle 11 so as not to move. The pressing body 452 provided integrally with the lock body 450 pushes the abutting portion 42a to rotate the tripping claw 40, and the pivot 41 rotates together with the tripping claw 40. The pivot 41 pulls the wire rope 52 to open the microswitch 501 and pull it off so that no voltage can be applied to the coil.

As shown in FIGS. 10 to 12, a micro switch 500 is arranged in the vicinity of the actuating member 32, and the lever 520 is pressed by the actuating member 32 to rotate the actuating member 32 when the gas pressure is reduced. The lever 520 is separated from the actuating member 32 so that the microswitch 500 is actuated. For this reason, at the time of gas decompression notice, the micro switch 500 activates an alarm device of a monitoring device at a remote location to notify the remote location that the gas pressure in the case is between the specified pressure and the lock operating pressure. You can

FIGS. 13 to 16 are explanatory views showing another embodiment of the structure showing the gas pressure drop notice. In the structure showing the gas pressure drop notice shown in FIGS. 13 (a), 13 (b), and 13 (c), the rotating plate 323 is a double plate whose base is fixed to the rotating shaft 322 with a required angle. Plate 323
a, 323b, and is biased in the clockwise direction as shown by the arrow. The plate body 323a is provided with a notice state engagement portion 330. 220 is an operating rod 22
It is a round bar-shaped engagement adjusting member attached to (not shown in FIGS. 13 to 16).

When the gas pressure in the working case 10 is in the specified pressure state,
As shown in FIGS. 13A and 13B, the plate body 323b is engaged with the engagement adjusting member 220 at the side edge 320a. When the gas pressure in the case 10 becomes low, the bellows 21 expands. As the bellows 21 expands, the engagement adjusting member 2
20 moves upward in FIG. 13, and the engagement adjusting member 2
The engagement state between 20 and the plate body 323b is released. When the engagement state is released, the engagement adjustment member 220 is engaged with the advance notice state engagement portion 330 to be in the advance notice state as shown in FIG. 13C.

In the structure shown in FIGS. 14 (a), 14 (b) and 14 (c) showing the notice of gas pressure drop, the rotating plate 323 is fixed to the rotating shaft 322, as shown by the arrow. It is biased clockwise. The rotating plate 323 is formed with an engaging hole 320b that is eccentrically provided with respect to the rotating shaft 322. The counterclockwise direction edge of the engagement hole 320b is the advance notice state engagement portion 330. Reference numeral 220a is an engagement adjustment member formed of a round bar, and the tip of the advance notice engagement projection 22 is eccentric from the center and is formed at the end in the clockwise direction.
1 is provided.

When the gas pressure in the working case 10 is in the specified pressure state,
As shown in FIGS. 14A and 14B, the engagement adjusting member 220
a is inserted into the engagement hole 320b, and the engagement adjustment member 2
20a is engaged with the engagement hole 320b. When the gas pressure in the case 10 becomes low, the bellows 21 expands. As the bellows 21 expands, the engagement adjusting member 2
20a moves upward in FIGS. 14B and 14C, and the engagement state between the engagement adjusting member 220a and the engagement hole 320b is released. By releasing the engaged state, FIG.
As shown by, the advance notice state engagement projection 221 is engaged with the advance notice state engagement portion 330 to enter the advance notice state.

In the structure shown in FIGS. 15 (a), 15 (b), and 15 (c) showing the notice of gas pressure drop, the rotating plate 323 is fixed to the rotating shaft 322, as indicated by the arrow. It is biased clockwise. The rotating plate 323 is formed with an engaging hole 320b that is eccentrically provided with respect to the rotating shaft 322. A groove-like decompression notice guide portion 321 is formed in the counterclockwise direction from the engagement hole 320b. The edge of the decompression advance notice guide portion 321 is a notice state engagement portion 330. 220b is an engagement adjusting member formed of a round bar,
An advance notice engagement projection 222 is formed at the center of the tip.

When the gas pressure in the working case 10 is in the specified pressure state,
As shown in FIGS. 15A and 15B, the engagement adjusting member 220
b is inserted into the engagement hole 320b, and the engagement adjusting member 2
20b is engaged with the engagement hole 320b. When the gas pressure in the case 10 becomes low, the bellows 21 expands. As the bellows 21 expands, the engagement adjusting member 2
20b moves upward in FIGS. 15 (b) and 15 (c),
The engagement state between the engagement adjusting member 220b and the engagement hole 320b is released. When the engagement state is released, the notice state engagement projection 222 is moved to the pressure reduction notice guide portion 3 as shown in FIG.
After passing through 21, the state is engaged with the notice state engagement portion 330 to enter the notice state.

In the structure shown in FIGS. 16 (a), 16 (b) and 16 (c) showing the notice of gas pressure drop, the rotating plate 323 is fixed to the rotating shaft 322, as indicated by the arrow. It is biased clockwise. An engaging notch recess 320c is formed at the edge of the rotating plate 323. The counterclockwise end of the engaging cutout recess 320c is an engaging step 320d. The decompression notice guide portion 32 that is notched in the counterclockwise direction from the engagement cutout recess 320c through the engagement step portion 320d.
1 is formed. A notice state engagement portion 330 is formed from the pressure reduction notice guide portion 321 to the end edge in the counterclockwise direction.

Reference numeral 220c is an engagement adjusting member formed of a round bar, and a notch 224 is formed at a required depth at a half of the tip end thereof, and a noticeable state engagement projection 223 is formed by the remaining portion. The engagement adjustment member 220c has an engagement cutout recess 320c such that the cutout 224 faces the rotation shaft 322.
Are located in

When the gas pressure in the working case 10 is in the specified pressure state,
As shown in FIG. 16A, the engagement adjusting member 220c is engaged with the engagement step portion 320d. When the gas pressure in the case 10 becomes low, the bellows 21 expands. As the bellows 21 expands, the engagement adjusting member 2
20c moves in the paper spine direction in FIGS. 16A and 16B, and the engagement state between the engagement adjustment member 220c and the engagement step portion 320d is released. When the engagement state is released, the advance notice state engagement projection 223 passes through the pressure reduction advance notice guide portion 321 and is engaged with the advance notice state engagement portion 330 to be in the advance notice state.

13 to 16, the present invention is not limited to the illustrated embodiment, such that the protrusion length of the advance notice engagement projection can be changed by the adjusting member. Various modifications are possible within the description of the range.

[0047]

The present invention has the above-mentioned structure and has the following effects. (A) The gas pressure enclosed in the gas switch is between the specified pressure and the lock operating pressure before the operating pressure falls to the lock operating pressure at which the operating handle is locked. Since it is possible to display in advance that the operation handle of the vessel is locked and the opening / closing operation cannot be performed, it is possible to prepare in advance and take countermeasures such as replacing the gas switch before that.

(B) With the decompression display device, it is possible to visually recognize the decrease in gas pressure at the site. Further, by using the electrical contacts, it is possible to confirm the notice of the gas pressure drop even at a distant business office or a monitoring office.

[Brief description of drawings]

FIG. 1 is a front view showing the entire gas switch according to the present invention.

FIG. 2 is a side view of the gas switch shown in FIG.

FIG. 3 is an explanatory cross-sectional view of a pressure detection device and a reduced pressure display device.

FIG. 4 is an explanatory diagram showing a relationship between a pressure detection device and a decompression display device with a display cover removed.

5 is a cross-sectional view taken along line AA of the operating member shown in FIG.

6 is a sectional view showing another embodiment of the actuating member shown in FIG.

FIG. 7 is a partially cutaway explanatory view of a decompression display device and a lock device for an operation handle.

FIG. 8 is a schematic explanatory view seen from the direction C in FIG. 7.

9 is a schematic explanatory view of a main part as viewed from the direction D in FIG.

FIG. 10 is an explanatory view showing a correlation between movements of an operating member and an interlocking plate in accordance with a change in gas pressure inside the gas switch, and showing a specified pressure state.

FIG. 11 is an explanatory diagram showing a correlation between movements of an operating member and an interlocking plate in accordance with a change in gas pressure in the gas switch, and showing a preliminary state of pressure reduction.

FIG. 12 is an explanatory diagram showing a locked state of the operation handle, showing a correlation between movements of the operating member and the interlocking plate with a change in gas pressure in the gas switch.

FIG. 13 is an explanatory diagram showing another embodiment of a structure showing a notice of a decrease in gas pressure.

FIG. 14 is an explanatory view showing another embodiment of a structure showing a notice of a decrease in gas pressure.

FIG. 15 is an explanatory view showing another embodiment of a structure showing a notice of a decrease in gas pressure.

FIG. 16 is an explanatory view showing another embodiment of the structure showing a notice of a decrease in gas pressure.

[Explanation of symbols]

 1 Gas Switch 10 Case 11 Operation Handle 2 Pressure Detecting Device 21 Bellows 22 Actuating Rod 220, 220a, 220b, 220c Engagement Adjusting Member 221, 222, 223 Warning State Engagement Protrusion 224 Cutout 23 Engagement Adjusting Member 3 Decompression Display Device 310 Engagement part 32 Actuating member 320 Engagement part 322 Rotating shaft 323 Rotating plate 33 Display cover 34 Interlocking plate 340 Display part 341 Engaging part 36 Interlocking plate shaft 360 Engaging part 4 Lock device 40 Tripping claw 41 Pivot axis 42 Interlocking plate engaging part 43 Lock member engaging part 45 Lock member 450 Lock body 451 Stopper pin 48 Spring

Claims (2)

[Claims] 1. The gas pressure enclosed in the gas switch is detected when the pressure of the gas has dropped to a lock operating pressure for locking the operating handle, and this state is displayed by an audible signal and / or a visible signal. With this, the operating handle is locked, and before the pressure of the enclosed gas drops to the lock operating pressure, it is detected that the pressure of the enclosed gas is between the specified pressure and the lock operating pressure. Is displayed by an audible signal and / or a visible signal, the method for displaying a decrease in gas pressure of a gas switch. 2. A pressure detecting device comprising an actuating means which is actuated when the pressure of the gas enclosed in the gas switch is lower than a prescribed pressure, and an interlocking means which transmits the movement of the actuating means to another. (2) and a reduced pressure display device comprising means for displaying the state of the pressure of the enclosed gas by an audible signal and / or a visible signal (3)
And a lock device (4) for locking the operation handle by transmitting the movement of the interlocking means to the locking means via the transmitting means when the pressure of the enclosed gas drops to the lock operating pressure. A gas switch, characterized in that the decompression display device (3) includes means for indicating that the pressure of the enclosed gas is between a specified pressure and a lock operating pressure.