JPS595519A - 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 power circuit breaker having a self-maintaining function in the closing position of the circuit breaker.

Traditionally, in order to cut off and turn on high voltage and high current,
A gas breaker is used. In breakers, the high-voltage contacts must be moved at high speeds, so the recent trend is to use hydraulic circuits for their operation. This hydraulic operation circuit usually includes 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 solenoid that drives the operating valve. Consists of a valve and a shutoff solenoid valve.

However, this type of conventional hydraulic circuit has the following drawbacks regarding its self-maintenance.

When a circuit breaker is hydraulically operated, it is preferable to provide the hydraulic operating circuit with a self-holding function in order to prevent the contacts from inadvertently moving from the closing position or the closing position. However, since the closed state of the breaker is always maintained except for system switching or inspections, it is not uncommon for it to last several months, and it is problematic from both safety and technical perspectives to keep the closing solenoid valve energized during this time. many. Therefore, the general rule is to provide the hydraulic circuit itself with a self-holding function without using electrical means such as a solenoid valve.
In the past, this was done mostly on the main valve side, so hydraulic pressure could not be used effectively.

In other words, in general, when attempting to self-retain a valve, the structure and operation of the valve become complicated, and it is inevitable that the pressure oil circuit will be short-circuited temporarily during the operation period of the valve.
If this happens in a main valve with a large size and a large amount of oil, a large amount of pressure oil will be released even for a short period of time, resulting in a large waste of pressure oil.

The present invention eliminates these drawbacks and provides an efficient, simple, economical, and highly reliable hydraulic operating circuit.

In other words, the hydraulic operating circuit of the present invention incorporates a highly efficient self-holding mechanism that utilizes its own oil pressure, which is comprised of two hydraulically operated switching valves, on the side of the operating valve with a small amount of oil. By providing a self-holding mechanism in the main valve, the side structure and operation of the main valve are simplified, preventing short-circuiting of the hydraulic circuit in the main valve and preventing large amounts of pressure oil from being released, and the self-holding operation uses external energy. It was done without
In addition to suppressing hydraulic loss in the entire circuit as much as possible, the structure of the main valve, which accounts for a large amount of structural weight, has been simplified to reduce oil and oil pressure.
The structure of the entire hydraulic circuit is simplified, which reduces the cost of the entire hydraulic circuit and also makes it highly reliable.

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

In the figure, (1) is a power breaker, (2) is a hydraulic cylinder that operates the breaker (1), (3) is a main valve that sends pressure oil for operation to the hydraulic cylinder (2), and (4) is a hydraulic cylinder that operates the breaker (1). ) is an operating valve that sends operating pressure oil to the main valve (3), (5) and (
Reference numeral 6) represents a closing solenoid valve and a shutoff solenoid valve that drive the operation valve (4), respectively.

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

The operating valves (4) are two hydraulically operated three-point/two-position switching valves (12/) (1) having a P port, an A port, and an R port.
It is mainly composed of 2a).

The first hydraulically operated switching valve (12/) includes a ball valve α3 that controls opening and closing between the P port and the A port, a ball valve 0 control that controls the opening and closing between the A port and the R port, and an operation pinuton for the ball valve α]αΦ. (1 phrase, and its two control rooms (16/) (1
6, 2) etc. A pressure oil supply source Q7) is connected to the P port of this valve (12/), and the A port is connected to the main valve (3).
operation chamber 01, and P of the second hydraulically operated switching valve (12a).
A closing solenoid valve (5) is connected to the operation chamber (16/) of the first hydraulically operated switching valve (12/).

The second hydraulically operated switching valve (12a) is a Borl valve α frame that controls opening and closing between the P boat and the A port and opening and closing between the A port and the R port, an operation pinuton α0 of the ball valve 08), and its operation. It has a room (a), etc. The A port of this valve (12, 2) is connected to another operation chamber (16) of the first hydraulically operated switching valve (12/), and a cutoff solenoid valve (6) is connected to the control chamber of the first hydraulically operated switching valve (12/). is connected.

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

FIG. 1 shows a case where the breaker (1) is in the cutoff state.

ing. Therefore, when the closing solenoid valve (5) is energized, this valve (5) moves to the left side, sends pressure oil to the operation chamber (16/) of the first hydraulic operation switching valve (12/), and operates it. The piston α0 moves to the left, opening the connection between the P port and the A port, and at the same time closing the connection between the A port and the R port, and the pressure oil sent from the pressure oil supply source α is transferred from the A port to the main valve. It is sent to the operation room diagram (3) and the P port of the second hydraulically operated switching valve (12 pieces).

The pressure oil sent to the operation chamber 4 of the main valve (3) moves the operation pinuton (8) to the left side, and the P port 1--A of the main valve (3)
Open up space between boats. The hydraulic cylinder (2) has a larger pressure receiving area on the bore side than on the rod side, so the P port +-
- By opening the A port, the accumulator θ
Pressure oil of η enters the bore side of the cylinder (2), and after the piston moves to the left, the oil flow stops.

In other words, the pressure on the cylinder bore side is the accumulator α■
and the pressure in the operating chamber αQ of the main valve (3) 9, the operating piston (8) and the poppet valve (7) are spring e21
) returns to the right side by force, and connects the p port of the main valve (3) and the
Close the boat.

In this case, since the poppet valve (9) remains held at the left nutlok end by the nupling, the circuit is not connected to the low pressure side when the hydraulic cylinder (2) is driven.

On the other hand, the pressure oil sent to the P boat of the second hydraulically operated switching valve (12J) enters the operation chamber (16x) of the first hydraulically operated switching valve (12/) via the P port and the A boat. Push the operating piston αFJ further to the left.

The breaker performs the closing operation through the series of operations described above, but
During the closing operation, an auxiliary switch (not shown) switches to open the electric circuit that issues the closing command and demagnetizes the closing solenoid valve (5). Due to this demagnetization, the solenoid valve (5) performs a return operation to the right by the return spring, and the operation chamber (16) of the first hydraulically operated switching valve (12/)
The pressure oil in the control chamber (16J) returns to the tank, but the pressure oil in the operation chamber (16J) remains as it is, so the operation piston αG remains moved to the left, and as a result, the closing solenoid valve (
Pressure oil is retained in the operation chamber a1 of the main valve (3) despite degaussing in step 5), the piston of the hydraulic cylinder (2) is self-retained at the left nut lock end, and the breaker (1) is closed. Continue the condition.

The pressure receiving areas of the operation chambers (16/) and (16x) are made larger than the pressure receiving area of the ball valve (I3), so that the operating piston αυ moves to the left against the hydraulic pressure applied from the left side of the pole valve α. Needless to say, it must be able to be moved.

To move the piston of the self-holding hydraulic cylinder (2) to the right, that is, to turn the breaker (1) into the 1 or OFF state, 1. Energize the shut-off solenoid valve (6).

By doing this, the second hydraulically operated switching valve (12, 2
Pressure oil enters the operation chamber (1) of ) and moves the operation piston to the left. By moving the operating piston H to the left, the operating chamber (1) of the first hydraulically operated switching valve (12/)
The pressure oil that accumulates in the main valve (3) returns to the tank via the second hydraulically operated switching valve (12J), and as a result, the operating unit α moves to the right and accumulates in the control chamber Q0 of the main valve (3). Pressure oil is returned to the tank via the first hydraulically operated switching valve (12/).

As a result, the poppet valve (9) of the main valve (3) and the cylinder (
Due to the pressure of the pressure oil stored on the bore side of the main valve (3), it moves rapidly to the right against the force of the spring (A).
Open the port and R port to release the pressure oil on the cylinder pore side to the tank. Pressure oil is constantly supplied to the rod side of the cylinder (2) from the accumulator (0), so
When the pressure oil on the cylinder pore side is returned to the tank, the piston of cylinder (2) rapidly moves to the right, and when the piston of cylinder (2) reaches the right end and the shutoff operation is completed, the cylinder ( The bore side of 2) is at atmospheric pressure, and the poppet valve (9) of the main valve (3) has a spring (a).
It returns to the left side by the force of , closes the A boat and R boat of the main valve (3), and prepares for the next closing command.

In this state, the pressure oil of the accumulator αυ is acting on the rod side of the cylinder (2), so the breaker is held in the cutoff position.

In the embodiment shown in FIG. 1, only a self-holding mechanism is incorporated in the operating valve (4). However, the recent trend is that the operation valve (
4) etc. are often incorporated with a so-called pumping prevention mechanism, and if necessary, a hydraulic operation circuit incorporating an additional pumping prevention mechanism etc. may be formed in the operation valve (4) etc. Naturally, this is within the scope of the present invention.

It goes without saying that in the embodiment shown in FIG. 1, the hydraulically operated switching valves (12/) and (12) are of the pole valve type, or may be changed to a check valve type or a spool valve type. .

Further, the supply source 07) of pressure oil to the operating valve may be directly connected to the accumulator 0]) without being provided separately.

Furthermore, the main valve (3) is not limited to the embodiment shown in FIG. In this case, since the self-holding function is provided on the operation valve (4) side, the main valve (3) may have a simple structure and simple operation, thereby preventing short circuits of the main valve (3). As mentioned above, this prevents the pressure oil from ejecting to the low pressure side and suppresses the oil pressure loss as much as possible.

As is clear from the above description, the present invention is capable of self-holding the breaker in the closed state without constantly energizing the solenoid valve, and also because this self-holding mechanism is provided on the operating valve side. This simplifies the structure and operation of the main valve, prevents large amounts of pressure oil from being released from the main valve, and even if there is a short circuit in the hydraulic circuit on the operating valve side, the absolute amount of oil is small, so the release can be prevented. The loss is extremely small, and together with the fact that external energy is not required for the self-holding mentioned above, this has a great effect on the effective use of hydraulic pressure. In addition, the present invention simplifies the structure of the main valve, which occupies a large structural weight, which simplifies the structure of the entire hydraulic circuit, reduces its complexity, and also improves its reliability. The effects are great, such as increasing

[Brief explanation of drawings]

FIG. 1 is a circuit diagram showing an example of a hydraulic operation circuit embodying the present invention. In the figure, 1: breaker, 2: hydraulic cylinder, 8: main valve,
4: Operation valve, 5: Closing solenoid valve, 6: Shushingetsu solenoid valve, 12/, 12 hydraulic operation switching valve, 16/
, 16.2: Control room. Applicant Sumitomo Precision Industries Co., Ltd. Voluntary Procedure 'Amendment August 26, 1980 Commissioner of the Patent Office Kazuo Wakasugi 1, Indication of the Case 1982 Patent Application No. 114287 2, Title of 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 6, "Detailed description of the invention" column of the specification subject to amendment and drawing 7, Contents of amendment (1) No. 1 of the specification From line 16 to line 17 on page 2, “
...The closed state is always maintained except in the case of system switching or inspection, so it is not uncommon for it to last for several months. It is not uncommon for it to last for several months as it is always maintained except in certain cases.
..." will be corrected. (2) On page 9, line 13 of the specification, it says "...the breaker is connected to the piston of cylinder (2)...".
・The breaker performs the breaking operation. The piston of cylinder (2) is corrected to...''. (3) Correct the attached sheet of Figure 1 of the drawing.

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 operating valve is provided with a hydraulically operated switching valve having two operating chambers as means for controlling pressure oil for operating the main valve, and a pipe line from a closing solenoid valve is connected to one of the operating chambers,
A hydraulic operating circuit for a circuit breaker, characterized in that a branch line for the main valve operating pressure oil is connected to the other operating chamber via a second hydraulically operated switching valve operated by a blocking solenoid valve.