JPH0795416B2 - Hydraulic operating device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a hydraulic operating device having an accumulator installed for operating an electric power breaker, for example.

(Prior Art) In recent years, the performance of circuit breakers provided in the circuits has improved remarkably as the voltage and capacity of transmission systems have increased, and SF6 gas insulation has been adopted as a typical example. Many gas circuit breakers are used. There are various types of gas breaker operating devices, but the hydraulic operating type is often used because of its small size, high output, excellent responsiveness, and easy noise reduction. The breaker can be made smaller and lighter.

Hydraulic operation devices for these gas circuit breakers are roughly divided into hydraulic cylinders that apply opening / closing operation force to the circuit breaker of the circuit breakers, and oil tanks that store discharged oil from the hydraulic cylinders and use it as high pressure oil again with an oil pump. And an accumulator that receives the high-pressure hydraulic oil sent from the oil tank and the high-pressure gas sent from the compressor, separated by the piston partition wall. Here, the high-pressure hydraulic oil of the hydraulic cylinder is sent to the drive mechanism of the shutoff portion when the shutoff portion is opened and closed.
At this time, the accumulator has a function of constantly applying a predetermined driving force to the working piston even if the hydraulic cylinder consumes the working oil because the piston partition moves due to the expansion of the high-pressure gas to apply the pressure to the working oil. I do.

Therefore, in the hydraulic operating device of the power breaker,
When the high-pressure gas in the accumulator leaks and becomes lower than a certain pressure, the pressure of the high-pressure hydraulic oil in the hydraulic cylinder also becomes low, and the necessary opening / closing driving force for the cut-off portion of the power breaker cannot be obtained. Therefore, in the accumulator, a seal component is used in the piston partition wall or the like to prevent leakage as much as possible.

The seal part between the piston and the cylinder that separates the high pressure gas and high pressure hydraulic oil of the accumulator has the function of sealing between the high pressure gas and the high pressure hydraulic oil, as well as the quick contact with the hydraulic cylinder when opening and closing the circuit breaker. It is required that the piston slide smoothly in the cylinder so that high pressure hydraulic oil can be supplied to the cylinder. In general, regarding sealing parts, the relationship between the sealing function and the sliding function is inversely proportional, and those with excellent sealing function tend to have poor sliding function, and those with excellent sliding function tend to have poor sealing function. . Therefore, the seal component of the piston is inevitably inferior in sealing function to the seal component used for the other fixed portion.

(Problems to be solved by the invention) On the other hand, the accumulator used in the hydraulic operating device of the power breaker is a gas pressure of high-pressure gas sealed with a piston in between when the power breaker is normally used. And the hydraulic pressure of the high-pressure hydraulic oil are equal pressure, the high-pressure gas leaks from the high-pressure gas chamber to the high-pressure hydraulic chamber, and vice versa. , Can be easily prevented.

However, when the oil pressure is reduced to atmospheric pressure, such as when inspecting the power breaker, the high-pressure operating oil chamber of the accumulator becomes atmospheric pressure and only the high-pressure gas chamber becomes high pressure. The amount of high-pressure gas leaking into the oil chamber increases. If the amount of leakage of this high-pressure gas is large, the gas pressure will decrease even if the oil pressure is increased again after inspection of the circuit breaker has been completed. You will not be able to get it with a cylinder. This situation causes the circuit breaker to be inoperable and causes serious damage to the power system.

An object of the present invention is to provide a hydraulic pressure control device that can prevent leakage of high pressure gas enclosed in an accumulator from a piston portion and can always provide stable hydraulic pressure control force.

[Structure of the Invention] (Means and Actions for Solving Problems) In the hydraulic operation device according to the present invention, the high-pressure hydraulic oil chamber has an atmospheric pressure between the piston of the accumulator and the high-pressure hydraulic oil chamber. At this time, the high pressure gas chamber is characterized in that a seal portion is formed to prevent the high pressure gas from leaking to the atmosphere side, and even if the high pressure hydraulic oil chamber side temporarily becomes atmospheric pressure, the high pressure gas chamber is always The high pressure is maintained, and the accumulator function can be continuously exerted by returning the high pressure hydraulic chamber to the high pressure.

(Examples) Hereinafter, the present invention will be described with reference to Examples shown in FIGS. 1 to 5.

First, referring to FIG. 5 showing a case where the hydraulic operating device of the present invention is applied as an operating device of a power breaker, the hydraulic operating device of the present invention is roughly classified into a breaking portion of a power breaker 1 of a driven body. A hydraulic cylinder 3 having a piston 2 for applying an opening / closing operation force, and a hydraulic pump 5 driven by a motor 4 when the high pressure hydraulic oil of the hydraulic cylinder 3 is discharged.
And the oil tank 6 to be used as high pressure hydraulic oil again.
It is composed of a system including an accumulator 8 having a piston 7 that separates high-pressure hydraulic oil sent from the compressor and supplied to the oil tank 3 and high-pressure gas sent from the compressor source.

In the hydraulic operating device shown in FIG. 5, the power interrupter 1 performs the closing operation and the closing operation by supplying and discharging the high pressure hydraulic oil of the accumulator 8 to the hydraulic cylinder 3 by the closing valve 9 ON and the closing valve 9 OFF. Controlled. At the time of this closing and closing operation, the high pressure hydraulic oil of the hydraulic cylinder 3 is consumed, or the high pressure gas and the high pressure hydraulic oil are constantly accumulated in the accumulator 8, so that the driving force for the piston 2 in the hydraulic cylinder 3 is secured. Has been done. Therefore, the accumulated pressure of the accumulator 8 is an important element for controlling the closing and closing operations of the power breaker 1, and the high-pressure gas sealed inside should not leak.

As shown in FIG. 1, the accumulator 8 used in the hydraulic operating device according to the present invention has the high pressure gas chamber A divided by the piston 7 and the high pressure gas 10 sealed therein. The high pressure hydraulic oil 11 sent from the oil tank 6 shown in FIG. 5 and supplied to and discharged from the hydraulic cylinder 3 is sealed. A seal member 12 having a sliding function and a sealing function is provided on the sliding surface of the piston 7 with the accumulator 8. Further, the illustrated upper opening of the accumulator 8 is sealed by a top cover 13 via a sealing member 14, and the top cover 13 is provided with a charge valve 15 connected to a supply source of the high pressure gas 10. Is sealed via a seal member 16 with a bottom cover 18 having an oil hole 17 connected to the piping system of FIG.

Further, in the accumulator 8 used in the present invention, in order to prevent the high pressure gas 10 in the high pressure gas chamber A from leaking to the high pressure hydraulic oil chamber B side as much as possible, the piston 7 and the bottom cover
It is characterized in that a seal portion (21) is formed on an abutting surface with (18). That is, in FIG. 1, a protrusion 19 is formed on the side of the high pressure hydraulic oil chamber B of the piston 7, and a recess 20 having a tapered surface 20a is formed on the side of the high pressure hydraulic oil chamber B of the bottom cover 18, so that the piston 7 descends. Bottom cover 18
The projection 19a of the projection 19 of the piston 7 abuts on the tapered surface 20a of the bottom cover 18 to form the metallic seal portion 21 when the piston 7 abuts against. Moreover, when the projection 19a of the piston 7 abuts the tapered surface 20a of the bottom cover 18 to form the metal surface seal portion 21, the metal surface seal portion 21, the lower surface of the piston 7, the bottom cover, as shown in FIG. A small amount of high pressure gas leaking from the seal member 12 of the piston 7 on the upper surface of 18 and the inner wall surface of the accumulator 8.
It is configured to form a compartment 22 for receiving 10.

Next, the hydraulic operating device according to the present invention, in particular the accumulator 8
The operation of will be described. When the hydraulic operating device of the present invention applied to the power breaker 1 of FIG. 5 is operating in a normal operating state, the piston 7 of the accumulator 8 occupies the position shown in FIG. The state of FIG. 1 shows that the gas pressure of the high-pressure gas 10 in the high-pressure gas chamber A and the hydraulic pressure of the high-pressure hydraulic oil chamber 11 are the same.

Now, when the hydraulic pressure in the high-pressure hydraulic oil chamber B is reduced to atmospheric pressure during inspection of the power breaker 1, the piston 7 is pushed by the high-pressure gas 10 and hits the bottom cover 18 as shown in FIG. Hold in contact. In the state shown in FIG. 2, the high-pressure gas chamber A has the pressure of the high-pressure gas 10 and the high-pressure hydraulic oil chamber B has the atmospheric pressure.
Of the high pressure gas chamber A leaks to the atmosphere side of the high pressure hydraulic oil chamber B from the high pressure gas chamber A.

However, in the state shown in FIG. 2, the protrusion of the protrusion 19 of the piston 7
19a contacts the tapered surface 20a of the recess 20 of the bottom cover 18 to form a metal surface seal portion 21. This metal face seal part
Even if the high-pressure gas 10 leaks from the seal member 12 of the piston 7, 21 is stored in a small chamber 22 formed by the piston 7, the bottom cover 18 and the inner wall of the accumulator 8, and the gas leaked into this small chamber 22 is a high-pressure gas. A small amount of leakage until the pressure becomes the same as the chamber A side is suppressed, and gas is prevented from leaking to the oil hole 17 side.

Therefore, in the hydraulic operating device according to the present invention which employs the accumulator 8, even if the high pressure hydraulic oil of the hydraulic cylinder 3 and the accumulator 8 becomes atmospheric pressure when the power breaker 1 of the driven body is inspected. Since the side of the high-pressure gas chamber A is maintained at the pressure of the high-pressure gas 10, the high-pressure hydraulic oil is restored, so that the power breaker 1 can be smoothly turned on and off.

Next, in another embodiment shown in FIG. 3, in order to form the metal surface seal portion 21, a recess 20 and a tapered surface 20a are provided on the high pressure hydraulic oil chamber B side of the piston 7, and the bottom cover 18 is provided. The protrusion 19 and the protrusion 19a are provided. Also in this embodiment, when the high-pressure hydraulic oil chamber B reaches the atmospheric pressure, the piston 7 is pushed by the high-pressure gas 10 and descends, and the projection 19 of the piston 7
The a comes into contact with the tapered surface 20a of the bottom cover 18 to form the metal seal portion 21 and the small chamber 22. The leakage of the high pressure gas 10 is suppressed to a very small amount of leakage until the gas pressure in the small chamber 22 becomes the same as the gas pressure in the high pressure gas chamber A.

Furthermore, in another embodiment shown in FIG.
In order to form the seal portion 21 on the abutting surface of the bottom cover 18 and the bottom cover 18, a packing 23 is provided on the surface of the bottom cover 18, and the packing 23 is pressed by a pressing plate 25 with a screw 24. In this push plate 25, the protrusion 26 thereof is inserted into the groove of the packing 23 to prevent the packing 23 from falling off. Therefore, also in the embodiment of FIG. 4, when the high-pressure gas chamber A side of the accumulator 8 is at high pressure and the high-pressure hydraulic oil chamber B side is at atmospheric pressure, the lower surface of the piston 7 contacts the packing 23 to form the seal portion 21. This prevents the high pressure gas 10 on the high pressure gas chamber A side from leaking to the atmosphere side of the oil hole 17.

EFFECTS OF THE INVENTION As described above, according to the present invention, the high pressure gas chamber and the high pressure hydraulic oil chamber have an accumulator that is partitioned by a piston, and the high pressure operating oil is provided between the piston and the high pressure hydraulic oil chamber of the accumulator. When the pressure in the high-pressure gas chamber is temporarily atmospheric, the high-pressure gas chamber is configured to form a seal to prevent high-pressure gas from leaking to the atmosphere. However, the high-pressure gas chamber is always maintained at a high pressure, and the high-pressure hydraulic oil chamber can be restored to a high pressure to continuously exert the accumulator function.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of an accumulator used in the hydraulic operating device of the present invention in a normal state, and FIG. 2 is a sectional view showing a state in which the high-pressure hydraulic oil chamber is at atmospheric pressure. FIG. 4 and FIG. 4 are cross-sectional views showing other different embodiments of the accumulator used in the present invention, and FIG. 5 is a system diagram showing a hydraulic operating device. 1 …… Power breaker (driven body) 3 …… Hydraulic cylinder, 6 …… Oil tank 8 …… Accumulator 7 …… Piston, 10 …… High pressure gas 11 …… High pressure hydraulic oil 12,14,16 …… Seal Member 13 …… Top cover 15 …… Charge valve 17 …… Oil hole, 18 …… Bottom cover 19 …… Protrusion, 19a …… Protrusion 20 …… Concave, 20a …… Tapered surface 21 …… Seal, 22… … Small chamber A …… High pressure gas chamber, B …… High pressure hydraulic oil chamber

Claims (3)

[Claims] 1. A hydraulic cylinder having a piston for applying an operating force to a driven body, an oil tank for receiving high-pressure hydraulic oil discharged from the hydraulic cylinder, and converting the discharged oil into high-pressure hydraulic oil again. An accumulator having a high-pressure hydraulic oil chamber for storing high-pressure hydraulic oil supplied from an oil tank and sent to the hydraulic cylinder, and an accumulator having a piston for separating the high-pressure hydraulic oil and a high-pressure gas sent from a high-pressure source, and high-pressure operation of the piston of the accumulator. A seal portion formed by abutting between a corner of a protrusion provided on the oil chamber side surface and a tapered surface of a recess provided on the bottom cover of the accumulator, and a sliding surface of the seal portion and the piston. A hydraulic operation device comprising a small chamber interposed therebetween. 2. A hydraulic cylinder having a piston for applying an operating force to a driven body, an oil tank for receiving high-pressure hydraulic oil discharged from the hydraulic cylinder, and converting the discharged oil into high-pressure hydraulic oil again. An accumulator having a high-pressure hydraulic oil chamber for storing high-pressure hydraulic oil supplied from an oil tank and sent to the hydraulic cylinder, and an accumulator having a piston for separating the high-pressure hydraulic oil and a high-pressure gas sent from a high-pressure source, and high-pressure operation of the piston of the accumulator. A seal portion formed by an abutment between the taper surface of the concave portion provided on the surface on the oil chamber side and the corner portion of the projection portion provided on the bottom cover of the accumulator, and the sliding surface of the seal portion and the piston. A hydraulic operation device comprising a small chamber interposed therebetween. 3. A hydraulic cylinder having a piston for applying an operating force to a driven body, an oil tank for receiving high-pressure hydraulic oil discharged from the hydraulic cylinder, and converting the discharged oil into high-pressure hydraulic oil again. An accumulator having a high-pressure hydraulic oil chamber for storing high-pressure hydraulic oil supplied from an oil tank and sent to the hydraulic cylinder, and an accumulator having a piston for separating the high-pressure hydraulic oil and a high-pressure gas sent from a high-pressure source, and high-pressure operation of the piston of the accumulator. A hydraulic operating device comprising a surface on the oil chamber side and a seal portion formed by abutment of a packing fixed to a bottom cover by a pressing plate.