JPS595520A - Hydraulic operation circuit for breaker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hydraulic operating circuit for a circuit breaker, which is provided with a pumping operation prevention mechanism to be held by the circuit breaker.

Traditionally, in order to cut off and turn on high voltage and high current,
A circuit breaker is used. In this breaker,
Due to the need to move high voltage contacts at high speeds, the recent trend is to use hydraulics for their operation.

This hydraulic operation circuit usually consists of a hydraulic cylinder that operates the breaker, a main valve that sends operating pressure oil to the hydraulic cylinder, an operating valve that sends operating pressure oil to the main valve, and a closing valve that drives the operating valve. Consists of a solenoid valve and a cutoff solenoid valve.

However, in conventional hydraulic circuits of this type, an abnormal operation of the hydraulic cylinder called pumping occurs. This is because the shutoff command has priority over the closing command, so if a shutoff command is issued while the closing command is continuing, the hydraulic cylinder will perform a shutoff operation, but if the closing command remains, Immediately after the breaker operation, the closing operation is performed again, and this is repeated until one of the commands is released, which can cause damage to the breaker or its hydraulic operating circuit. .

In addition, in a gas breaker, for example, a buffer type gas breaker, the arc-extinguishing fluid (SFt gas, etc.) in the buffer cylinder is compressed by moving the buffer cylinder or piston to increase the pressure, and the high-pressure arc-extinguishing fluid is Blows the arc to extinguish it. Therefore, with this breaker, it is necessary to sufficiently increase the pressure inside the buffer unlinder, so if a cutoff command is issued during the closing operation, the cutoff command is simply prioritized. If it is, the cutting operation will start in the middle of the closing operation, and in some cases, the pressure inside the rough-fire cylinder will not rise enough, and the arc generated by the preceding closing discharge will not be able to be extinguished, making it impossible to shut off. This may lead to a serious accident.For this reason, if a shutoff command is issued during the closing operation, it is recommended that the shutoff operation is not started until the closing operation is completely completed. No tuft pressure can be obtained and therefore high reliability cannot be obtained.

The present invention provides a hydraulic operation circuit that prevents a pumping operation without destroying the principle of giving priority to commands when shutting down, and when a shutoff command is issued during a closing operation, waits for the completion of the closing operation before performing a shutoff operation. It is something.

In the hydraulic operation circuit of the present invention, a hydraulic operation switching valve is provided on the operation valve that sends pressure oil for operation to the main valve as a means for controlling the pressure oil for operating the main valve, and the hydraulic operation switching valve is connected to the operation chamber of the hydraulic operation switching valve. A relief mechanism is provided between the solenoid valve to release the pressure oil flowing into the operation chamber after the closing operation time of the hydraulic cylinder has elapsed, so that the hydraulic pressure closing command issued by the closing solenoid valve is activated. After the end, it automatically disappears in the hydraulically actuated switching valve, and prevents pumping by preventing the closing command and the cutoff command from substantially overlapping, and in 1, the closing command disappears in the hydraulically actuated switching valve. Regardless of the situation, pressure oil continues to flow into the operation chamber to ensure that the closing operation is completed.

In addition, in the hydraulic operation circuit of the present invention, after the closing operation is completed, the pressure oil in the operation chamber of the hydraulically operated switching valve is released, so the hydraulically operated switching valve is provided with a self-holding mechanism to maintain the closed state. It is necessary to attach it. Since this self-holding mechanism maintains the principle of giving priority to the command in the event of an interruption, it is necessary to be able to immediately release it by operating the shutoff solenoid valve. It is also necessary to provide it independently of the relief mechanism so that the pressure oil flowing into the operation chamber is not released by a shutoff command.

Hereinafter, the present invention will be described in detail based on embodiments shown in the figures.

In the figure, (1) is a circuit breaker, (2) is a circuit breaker (1
)? : Hydraulic cylinder to be operated, (3) is the main valve that sends pressure oil for operation to the hydraulic cylinder (2), (4) is the main valve 3
), and (5) and (6) respectively represent the closing solenoid valve and the shutoff solenoid valve that fully drive the operating valve (4).

The main valve (3) has a P port, an A port, and an R port.
A type of two-position switching valve with a poppet valve (7) that controls the opening and closing between the P bow and A hoard, an operating piston (8) of the poppet valve (7), and a poppet valve that controls the opening and closing between the A port and the R port. It has a poppet valve (9), an operation chamber 00 for an operation piston (8), and a poppet valve (9). The P boat of the main valve (3) is connected to the rod side of the hydraulic cylinder (2) and the accumulator 0υ, which is the supply source of pressure oil.
The boat is connected to the bore side of the hydraulic cylinder (2).

The operation valves (4) are four hydraulically operated three-point/two-position switching valves (12/) to (12/) having P port, A port, and R port.
12s), and the relief mechanism has a second. It is mainly composed of the third hydraulically operated switching valve (11z) (123), and the self-holding mechanism is mainly composed of the fourth hydraulically operated switching valve (12g).

The first hydraulically actuated switching valve (12/) is a Pall valve that controls the opening and closing between the P port and the A port, and a Pall valve that controls the opening and closing between the A port and the R port. It is equipped with an operation piston ◇, and further has two operation chambers (16/) (16
, 2) etc. A pressure oil supply source θ''I) is connected to the P boat of this valve (12/), and the A boat is connected to the main valve (3).
operation chamber 00, and P of the fourth hydraulically operated switching valve (12a).
Connect to the boat.

The second hydraulically operated switching valve (12, l)
This valve (12) is connected to the operation piston a rotation of the ball valve (18) on the pole valve α, which controls the opening and closing between the boats and the opening and closing between the A boat 1 and the R boat, and its operation chamber (a).
, 2), the input solenoid pulp (5) is connected to the P boat, and the A boat is connected to the first hydraulically operated switching valve (12/).
Connect to the control room (16/).

The third hydraulically operated switching valve (123) includes a ball valve Q1) that controls the opening and closing between the P port and the A port, a ball valve (2) that controls the opening and closing between the A port and the R port, and a ball valve 121) (I) that controls the opening and closing between the A port and the R port. ), and its operation chamber (c), etc., and the ball valve (a) and the rod of the operation piston rod are separated by a distance d with no pressure oil entering the operation chamber (c), and the operation chamber (c) is separated from the ball valve (a). There is a delay of 1 time between the response of N[N@ and the operation of ball valve 0υ(a).

This delay time is set to be the same as or slightly longer than the time from the start of the closing operation to the end of the closing operation (closing operation time) of the hydraulic cylinder (2), and the distance d is set to ensure this delay time, as described below. It is determined from the relationship with the aperture amount of the crest valve (A). This third hydraulically operated switching valve (12
The closing solenoid valve (5) is connected to the P port of J), the A port is connected to the operation chamber of the second hydraulic operation switching valve (12p), and the closing solenoid valve (C) is connected to the operation chamber (C). Valve (5) is a throttle valve (A) with a check valve (C) connected in parallel.
Connected via δ.

The fourth hydraulically operated switching valve (12) is substantially the same as the second hydraulically operated switching valve (12), and the ball valve (5) is substantially the same as the second hydraulically operated switching valve (12).
, an operation piston rod, an operation chamber, etc., and the P boat is equipped with the first hydraulically operated switching valve (12/) as described above.
Boat A is connected, and Boat A is connected to the same hydraulically operated switching valve (1
2/) is connected to the control room (16, ri, and the control room -
A new solenoid valve (6) is connected.

Next, the operation of this hydraulic operation circuit will be explained.

FIG. 1 shows a case where the circuit breaker (1) is in a cutoff state. So now, when the closing solenoid valve (5) is energized, this valve (5) moves to the left, and the pressure oil is transferred to the first hydraulically operated switching valve (12) via the P port and the A port. It is sent to the operation chamber (L6/) of the hydraulically operated switching valve (12/).

As a result, the operation binuton aυ of the first hydraulically operated switching valve (12/) moves to the left, and the pressure oil from the pressure oil supply source (171) passes through the P port and the A port to the main valve (3). Control room 0
0 and the P port of the fourth hydraulically operated switching valve (12→).

The pressure oil sent to the operation chamber α0 of the main valve (3) is
-Move the cylinder (8) to the left side and open the main valve (3) between the P boat and the boat.The hydraulic cylinder (2) has a larger pressure receiving area on the P bore side than on the rod side, so the P hose 1
--By opening between the A boats, the pressure oil stored in the accumulator enters the bore side of the hydraulic cylinder (2), moves the pinuton at high speed, and the breaker (1) is activated. You can put it in.

On the other hand, the pressure oil sent to the P port of the fourth hydraulically operated switching valve (12g) passes through the P port and the A boat to the operation chamber (16, 2) of the first hydraulically operated switching valve (12/). After pushing the input button 00 further to the left, hold it at the left tail end.

When the auxiliary switch (not shown) switches during the closing operation of the breaker, the electric circuit that gives the closing command is opened and the closing solenoid valve (5) is demagnetized. ~ can hold itself in this position, so
Despite the demagnetization of the closing solenoid valve (5), the main valve (3)
Pressure oil is maintained in the operation chamber a0 of ) to maintain the circuit breaker (1) in the closed state.

Also, when the binuton of the cylinder (2) moves to the left and stops, the pressure on the bore side of the cylinder (2) becomes the same as the pressure in the operating chamber a0 of the accumulator 01) and the main valve (3), and the operating binuton ( 8) and the poppet valve (7) return to the right side by the force of the spring (to), closing the P boat and A port of the main valve (3).

The pressure receiving areas of the operation chambers (16/) and (16,2) are each made larger than the pressure receiving area of the ball valve 03, so that the operating binuton Q0 resists the hydraulic pressure applied from the left side of the port/X/(113). It is necessary to be able to move to the left.

On the other hand, a part of the pressure oil sent out from the input solenoid valve (5) passes through the throttle valve holder and is then transferred to the third hydraulically operated switching valve (12, ?).
) Enter the control room (c) and have the control binuton move ) to the left. However, by keeping a distance rtad between the rod of the operating piston (A) and the Pole valve (A), the Pole valve Qυ is maintained at least until the end of the closing operation of the hydraulic cylinder (2).
Since (a) is prevented from moving, the pawl valve Q1 must be opened after the closing operation of the hydraulic cylinder (2) is completely completed.
) (A) moves to the left side and sends the pressure oil from the pressure oil supply source (171) to the operation chamber (1) of the second hydraulically operated switching valve (12J) via the P boat and A port. , the operating piston α of the second hydraulically operated switching valve (12J) moves to the left side, and opens the operating chamber (16) of the first hydraulically operated switching valve (12/).
The pressure oil in /) is returned to the tank via A port and R-).

Even if the pressure oil in the operation room (16/) is released, there is still pressure oil in one operation room (16J), so the circuit breaker (
1) will not enter the cutoff operation.

To turn off the breaker (1), the cutoff solenoid valve (6) is energized, and the first hydraulically actuated switching valve (12) is energized.
/) is returned to the tank via the A port and R port of the fourth hydraulically operated switching valve (t>). That is, when the pressure oil in the operation chamber (16, 2) of the first hydraulically operated switching valve (12/) is released, the A port,
The R port opens, releasing the pressurized oil into the operation chamber αQ of the main valve (3), and the poppet valve (9) is rapidly activated by the pressure of the pressurized oil stored in the bore side of the cylinder (2). Move to the right side and open the A and R boats of the main valve (3) to release ml of pressure oil from the cylinder pore into the tank. Cylinder (2J
Since pressure oil is constantly supplied to the rod side of the cylinder (2) from the accumulator αυ, when the pressure oil on the bore side of the cylinder (2) is returned to the tank, the piston of the cylinder (2) rapidly moves to the right and shuts off. The device performs a shutoff action.

By the way, if a hydraulic pressure closing command remains at the time of this cutoff operation, the closing operation will start after the cutoff operation is completed, causing pumping, but in this hydraulic operation circuit, as described above, the first hydraulic operation switching The pressure oil in the operation chamber (16/) of the valve (12/) is automatically opened when the closing operation is completed, regardless of whether there is a closing command, and the state is the same as when the closing command is released, so the shutoff operation is completed. The closing operation is not started later. That is, pumping action is prevented.

In addition, if the cutoff solenoid valve (6) is energized during the closing operation, the pressure oil that has entered the operation chamber (16) of the first hydraulically operated switching valve (12/) will be released, but at least Until the end of the operation, there is no danger of the pressure oil in the operation chamber (16/) being released, and the pressure oil from the closing solenoid valve (5) continues to enter the operation chamber (16/) until the closing operation is completed. When the input operation is completed, the pressure oil in the above-mentioned operation chamber (16/) is released and the operation chamber (16/) is released.
, 2) has already been opened when the cut-off solenoid valve (6) is energized, so the cut-off operation is performed immediately, and after the cut-off operation is completed, the operation room (16/) is opened. Since the pressure oil is automatically released, there is no possibility of a pumping operation.

In addition, in the embodiment shown in the figure, hydraulically operated switching valves (12/) to (1
Although the 2-→hole valve type is used, it goes without saying that it may be changed to a check valve type or a null valve type.

In addition, the self-holding mechanism of the hydraulically operated switching valve (12/) is constructed by dividing the operating chambers of the hydraulically operated switching valve (12) and the hydraulically operated switching valve (12/) into two. It is not limited to this, but for example, a hydraulically operated switching valve (1
2/) may be mechanically connected to another hydraulically operated switching valve.

Further, it goes without saying that the relief mechanism and the main valve (3) are not limited to those of the first embodiment.

As is clear from the above explanation, since the present invention prevents pumping operation while retaining the principle of giving priority to the breaker command, it is possible to prevent damage to the breaker or its hydraulic operating circuit without impairing safety. In addition, if a cutoff command is issued during a closing operation, the shutoff operation is performed immediately after the closing operation is completed, so it can be applied, for example, to the hydraulic operation circuit of a buffer type breaker to ensure that sufficient buffer pressure is always maintained. This has the effect of ensuring reliable arc extinguishing operation and significantly increasing safety during closing operation.

Moreover, since the present invention prevents pumping and waits for the shutoff operation with a single relief mechanism, the mechanism is not only simple, but also because the relief mechanism and self-holding mechanism are provided on the side of the operating valve. This avoids complicating the structure of the main valve, which occupies a large amount of structural importance, and prevents pumping and waits for the shutoff operation with a simple circuit. Furthermore, since there are no packaging restrictions on the main valve, its operation becomes simpler and faster, and temporary short circuits in the hydraulic circuit at the main valve can be prevented, which is essential for preventing large amounts of pressure oil from being released. The invention is valid.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an example of a hydraulic operation circuit embodying the present invention. In the figure, ■ = breaker, 2: hydraulic cylinder, 8: main valve,
4: Operation valve, 5: Closing solenoid valve, 6: Shushingetsu solenoid valve, 12/~12: Hydraulic operation switching valve. Applicant: Sumitomo Precision Industries Co., Ltd. Applicant: Nissin Electric Co., Ltd. Voluntary procedure amendment August 26, 1980 Commissioner of the Japan Patent Office Kazuo Wakasugi 1, Indication of the case 1982 Patent Application No. 114288 2 Title of the invention Hydraulic operating circuit for circuit breaker 3, relationship with the case of the person making the amendment Patent applicant address: 2-6 Nishinagasu Hondori, Amagasaki City, Hyogo Prefecture Name: Sumitomo Precision Industries Co., Ltd. Representative: Shigeo Yoshii (and one other person) 4 Agent 5 Date of amendment order (Monday, Day, Showa 1920) (Document sending date: Month, Day, 1920) "Detailed explanation of the invention" column of the specification and Drawing 7, Contents of amendment (1) Page 3, No. 11 of the specification From line to line 12, “
... due to the preceding charging discharge..."
・This has been corrected to ``Due to the preceding discharge of input...''. (2) From line 18 to line 19 on page 3 of the specification:
...Rod and ball valve (a)..."
...Rod and ball valve (A)..." is corrected. (3) Revise Figure 1 of the drawing as shown in the attached sheet.

Claims (1)

[Claims] (1) Hydraulic operation of a breaker that has a hydraulic cylinder that operates the breaker, a main valve that sends operating pressure oil to the hydraulic cylinder, and an operating valve that sends operating pressure oil to the main valve. In the circuit, the operation valve is provided with a hydraulically operated switching valve as a control means for the pressure oil for operating the main valve, and the pressure oil flowing into the operation chamber is connected between the operation chamber and the closing solenoid valve connected thereto. A relief mechanism is provided that opens after the closing operation time of the hydraulic cylinder has elapsed, and the hydraulic operation switching valve is further provided with a self-holding mechanism that is independent of the relief mechanism and that is released by a cutoff solenoid valve. Hydraulic operating circuit for a circuit breaker.