JPH0246614A - Fluid pressure operating device for switchgear - Google Patents

Abstract

PURPOSE:To make it possible to obtain a fluid pressure operating device for switchgear with an excellent reliability and response property by forming a high pressure chamber linking to a main valve, closing and opening the linking between the high pressure chamber and a liquid exhaust tank with the contact of a sheet surface and a valve formed in a small hollow, and linking the liquid in a compression chamber and in the liquid exhaust tank. CONSTITUTION:In a small hollow 30 linking to a compression chamber 29, a small diameter of piston 31, a connecting rod 32, and a valve 33 are installed movable integrally from the compression chamber 29 side. In a space surrounded by these member and a block, a high pressure chamber 38 is formed and linked to a main valve 16, while the linking of the high pressure chamber 38 and a liquid exhaust tank 19 is closed and opened by the engagement and the disengagement of a sheet surface 36 and the valve 33 formed in the small hollow 30, and the liquid in the compression chamber 29 and in the liquid exhaust tank 19 is linked through a check valve 45. The displacement of a large diameter of piston 25 moved by a dielectric element 26 which is extended and contracted following the voltage application gives a high speed and a large displacement to a small diameter of piston 31, and moreover, the liquid is supplied in the compression chamber 29 through a linking hole 41. As a result, a fluid pressure operating device for switchgear with an excellent reliability and response can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Field of Application) The present invention relates to a hydraulic operating device for a switchgear, which is an improved valve device of Pilot 1.

(Prior Art) In recent years, as the demand for electric power increases, switching devices such as circuit breakers and disconnectors have become larger in size. For this reason, operating devices for switching devices are required to have high output and excellent operational responsiveness.

In order to satisfy these requirements, in recent years, hydraulic operating devices using a liquid as a driving source and known from Japanese Patent Application Laid-Open Nos. 59-54128 and 59-54129, etc., have been generally adopted.

Here, the configuration of the intra-membrane hydraulic pressure operating device will be explained with reference to FIG. That is, an operating section 4 consisting of a piston 2 and a cylinder 3 is connected to a contact section 1 of the opening/closing device.

One side of the cylinder 3 with respect to the piston 2 is connected to an accumulator 6 in which pressurized fluid pressurized by a pump 5 is stored.

Further, the other side of the cylinder 3 is connected to an accumulator 6 via a main valve 7. This main valve 7 is controlled by a closing pilot valve 8 and a shutting pilot valve 9.

Then, the main valve 7 is controlled by operating the closing pilot valve 8 or the shutting pilot valve 9, and the contact portion 1 is opened and closed by charging and discharging the pressurized liquid to the main valve 7 side in the piston 2. It will be done.

Incidentally, both pilot valves 8 and 9 have conventionally employed electromagnetically driven solenoids. The output of this solenoid is determined by the ampere-turns of the coil, so to obtain high output it is necessary to increase the number of turns in the coil or to run a large current through the coil.

However, in this case, problems such as a decrease in responsiveness due to an increase in inductance and burnout of the coil due to Joule heat occur. For this reason, the responsiveness of the solenoids, that is, both pilots 1 to valves 8 and 9, naturally has a limit.

(Problem to be solved by the invention) As described above, the conventional pilot valve using a solenoid uses an electromagnetic drive system using a coil, so when obtaining a high output pilot valve, reliability is and responsiveness was decreased. This results in a reduction in the performance of the hydraulic operating device.

The present invention has been made in consideration of the above points, and an object of the present invention is to provide a hydraulic operating device for an opening/closing device that incorporates a pilot valve device with excellent reliability and responsiveness.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, in the present invention, a large diameter piston is slidably housed in a hollow part of a block of a pilot valve device, and one part of this large diameter piston is A piezoelectric element is fixed between the side and the block, and a compression chamber in which liquid is injected is formed on the other side of the large diameter piston, and a small diameter piston is integrally movable from the compression chamber side into a small hollow part connected to this compression chamber. The connecting rod and valve are housed, a high pressure chamber is formed in a space surrounded by these blocks and communicated with the main valve, and a seat surface and valve are formed in a small hollow part to communicate between the high pressure chamber and the drain tank. The compression chamber and the liquid in the drain tank are communicated via a check valve.

(Function) With this configuration, it is possible to achieve high-speed large displacement of the small diameter piston and to replenish the liquid in the compression chamber. A pressure manipulation device can be provided.

(Example) An example of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 is a schematic sectional view of the hydraulic operating device. The contact portion 10 of the switchgear includes a piston 11 and a cylinder 12.
An operating section 13 equipped with the following is connected.

Then, the contact portion 10 of the cylinder 12 with respect to the piston 11
A liquid chamber 12a formed on the side is connected to an accumulator 14 storing pressurized liquid pressurized by a pump (not shown). On the other hand, a liquid chamber 12b formed on the opposite side of the contact portion 10 of the cylinder 12 with respect to the piston 11 is connected to the accumulator 14 via a cylinder port 15, a main valve device 16, and a high pressure port 17.

The main valve device 16 also includes a liquid chamber 12b and an accumulator 14.
Alternatively, it includes a main valve 16a that switches communication with the drain port 18, and a valve block 16b that houses the main valve 16a. Namely. When the liquid chamber 12b and the accumulator 14 are in communication, that is, the main valve 16
When a rises in the figure, pressure liquid is filled into the liquid chamber 12b. As a result, the piston 11 moves to the left in the figure due to the difference in pressure receiving area, and the contact portion 10 closes. On the other hand, when the liquid chamber 12b and the liquid drain port 18 are communicated with each other, that is, when the main valve 16a is lowered, the pressurized liquid in the liquid chamber 12b is discharged from the liquid drain port 18. As a result, the piston 11 moves to the right and the contact portion 10 opens.

Note that the valve block 16b is a drain tank 1 containing hydraulic fluid.
It is stored in 9. Also, the drain port is drain tank 1.
Opens within 9pm. Further, the liquid chamber 12b is connected to the cylinder 1.
2 or within the valve block 16.

Switching of the main valve 16a between Il and II is performed by the closing pilot valve device 20 and the shutting pilot valve device 21. In other words, the closing pilot valve device 20 and the shutoff pilot valve device 21 are connected to the liquid chamber 1 which is connected to the back pressure section of the main valve 16a.
This is for charging and discharging the pressure liquid in 6c and 16d.

In addition, in Figure 1, the shutoff pilot valve device 21 is opened and the liquid chamber 1 is opened.
6d is discharged and the main valve 16a is lowered, indicating a shut-off state.

Next, the configuration of the input pilot valve device 20 will be explained in detail using FIG. 2. In addition, the pilot valve device 21 for shutoff
Since the configuration is the same as that of the input pilot valve device 20, the explanation thereof will be omitted. A large-diameter piston 25 is accommodated in a hollow portion 23 formed in the block 22 via a packing 24, which can freely rotate in a liquid-tight manner. Furthermore, a laminated ceramic piezoelectric element 26 is fixed to one side of the large diameter piston 25. The other side of this piezoelectric element 26 is the block 2
2 It is fixed to the inner wall. When the piezoelectric element 26 is energized via the lead wires 27 and 28, it expands and contracts due to the electrostrictive effect.

On the other hand, the hollow portion 23 on the opposite side of the piezoelectric element 26 with respect to the large-diameter piston 25 is filled with liquid to form a compression chamber 29 .

Roughly speaking, a small hollow portion 30 is formed within the block 22 and connected to the compression chamber 29. Inside this small hollow part 30, a small diameter piston 31, a connecting rod 32, and a valve 33 are housed integrally and movably from the compression chamber 29 side. Further, a gasket 34 is installed between the small hollow portion 30 and the small diameter piston 31. As a result, the compression chamber 29 is surrounded by the block 22, the large diameter piston 25, and the small diameter piston 31. The valve 33 is always pressed toward the small diameter piston 31 by the spring 35. In addition, a valve 33 is installed in the small hollow part 30 so that the small diameter piston 31 enters into the hollow part 23.
A sheet surface 36 is formed which is brought into contact with the sheet surface 36. The cross-sectional area of this seat surface 36 is made equal to the cross-sectional area of the small diameter piston 31.

In addition, the block 22, the small diameter piston 31, the connecting rod 3
2 and the valve 32 is a space surrounded by the liquid '91 shown in FIG.
6C through the liquid inflow port 37 and the high pressure chamber 38
form.

The small hollow portion 30 on the opposite side of the high pressure chamber 38 with respect to the seat surface 36 is communicated with the drain tank 19 via a drain port 39 and a pipe 40.

Furthermore, the compression chamber 29 and the drain tank 19 are communicated through a communication hole 41 and a pipe 42. In addition, the communication hole 4
A check valve 45 consisting of a check valve body 43 and a spring 44 is provided in the middle of the valve 1. This check valve 45 allows fluid to flow only from the drain tank 19 toward the compression chamber 29.

Next, the effects of the configuration of this embodiment will be explained. In the state shown in FIG. 2, when a voltage is applied to the piezoelectric element 26 via the lead wires 27 and 28, the piezoelectric element 26 expands due to the electrostrictive effect. As a result, the large diameter piston 25 fixed to the piezoelectric element 26 moves downward in FIG. Therefore, the connecting rod 32 and the valve 33 descend together with the small diameter piston 31 forming the compression chamber 29.

Although the displacement of the piezoelectric element 26 is normally small, such as several tens of JJIn, the displacement of the small diameter piston 31 is amplified by the cross-sectional area ratio of the small hollow portion 30. At this time, the liquid in the compression chamber 29 tries to flow to the drain tank 19 through the communication hole 41, but since the check valve 45 is provided in the middle of the communication hole 41, the liquid is not discharged through the communication hole 41. All of them act on the small diameter piston 31 without any problem.

Then, as the valve 33 descends against the force of the spring 35, the valve 33 separates from the seat surface 36. This results in
High pressure chamber 38 and drain port 39 are communicated.

Therefore, the liquid in the liquid chamber 16c shown in FIG.
The liquid is discharged into the drain tank 19 through the drain tank 19.

As a result, the main valve 16a rises in FIG. As the main valve 16 rises, the drain port 18 closes and the pressurized liquid in the accumulator 14 is drained through the high pressure port 17 and the cylinder boat 15.
The liquid flows into the liquid chamber 12b through the liquid chamber 12b. And screws 1 to 1
1 moves to the left, the contact portion 10 is closed, and the closing operation is completed.

Further, during the shutoff operation, the shutoff pilot valve device 21 operates to discharge the liquid in the liquid chamber 16d, thereby lowering the main valve 16a. This stops the pressure fluid in the accumulator 14 from flowing into the fluid chamber 12b.
The pressurized liquid inside is drained through the drain port 18. Therefore, the piston 11 moves to the right, the contact portion 10 opens, and the interrupting operation is completed.

In this embodiment, the piezoelectric element 26 is used as a drive source for the pilot valve device 20.21, and the combination of the large diameter piston 25 and the small diameter piston 31 allows the small diameter piston 31 to be displaced by a large amount at high speed. As a result, the closing and shutting off pit valve device 20 has excellent reliability and responsiveness.
．． 21 can be provided.

Furthermore, the compression chambers 29 of both pilot valve devices 20, 21 are communicated with the liquid in the drain tank 19 via the check valve 45, the communication hole 41, and the pipe 42. Therefore, even if the liquid in the compression chamber 29 leaks from the part where the packing 24. Reliability will further improve.

〔Effect of the invention〕

As explained above, in the present invention, a large-diameter piston is liquid-tightly and movably housed in a hollow part of a block of a pilot valve device, and a piezoelectric element is fixed between one side of this large-diameter piston and the block. A compression chamber in which liquid is injected is formed on the other side of the large-diameter piston, and a small-diameter piston, a connecting rod, and a valve are housed in a small hollow part connected to this compression chamber so as to be integrally movable from the compression chamber side. A high pressure chamber is formed in the space surrounded by the blocks and communicates with the main valve,
The communication between the high pressure chamber and the drain tank is opened and closed by the contact and separation of the seat surface formed in the small hollow part and the valve, and the liquid in the compression chamber and the drain tank are communicated through the check valve. The displacement of the large-diameter piston, which is moved by a piezoelectric element that expands and contracts with the application of voltage, causes a high-speed, large-scale displacement of the small-diameter piston, and
The liquid in the compression chamber can be replenished through the communication hole, and it is possible to provide a hydraulic operating device for an opening/closing device including a pilot valve device with excellent reliability and responsiveness.

[Brief explanation of the drawing]

Fig. 1 is a schematic sectional view of a hydraulic operating device for a switchgear according to an embodiment of the present invention, Fig. 2 is a sectional view of a closing pilot valve device shown in Fig. 1, and Fig. 3 is a general sectional view of a hydraulic operating device for a switchgear. It is a schematic block diagram of the hydraulic pressure operation device for apparatuses. 10... Contact portion, 11... Piston, 12
...Cylinder, 12a, 12b...Liquid chamber,
13... Operating unit, 14... Accumulator, 15... Cylinder port, 16... Main valve device, 1
6a... Main valve, 16b... Valve block, 1
6C, 16d...Liquid chamber, 17...High pressure port,
18... Drain port, 19... Drain tank, 2
0... Pilot valve device for closing, 21... Pilot valve device for shutting off, 22... Block, 23... Hollow part, 24...
...Putskin, 25...Large diameter piston, 26.
...Piezoelectric element, 27.28...Lead wire, 29
...Compression chamber, 30...Small hollow part, 31...
・Small diameter piston, 32...Connecting rod, 33...
Valve, 34...Packing, 35...Spring, 36...Seat surface, 37...Liquid inflow port, 39...Drainage port, 41...Communication hole, 43...Check valve Body, 45...Check valve.

Claims (1)

[Claims] In a hydraulic operating device for a switchgear, the contact part of the switchgear is opened and closed by an operating section having a piston and a cylinder, the operating section is controlled by a main valve, and the main valve is further controlled by a pilot valve device, The pilot valve device includes a block having a hollow portion therein, a large diameter piston slidably housed in the hollow portion via a packing in a fluid-tight manner, and a piezoelectric device fixed between the large diameter piston and the block. a compression chamber formed in a hollow portion on the opposite side of the piezoelectric element with respect to the large diameter piston and into which a liquid is injected; a small hollow portion formed in the block and connected to the compression chamber; A small-diameter piston, a connecting rod, and a valve are housed integrally and movably from the compression chamber side in the part, and a packing is installed between the small hollow part and the small-diameter piston, and the valve is pressed toward the small-diameter piston side. a high-pressure chamber formed in a space surrounded by the spring, the block, the small-diameter piston, the connecting rod, and the valve and communicated with a liquid that controls the main valve;
A seat surface that is formed in the small hollow part and opens and closes communication between the high pressure chamber and the drain tank by connecting and separating the valve, and communicates the liquid in the compression chamber and the drain tank via a check valve. A hydraulic operating device for a switchgear, comprising a communication hole.