JPS6011334Y2 - valve drive device - Google Patents

Description

[Detailed description of the invention] This invention has a large-diameter piston and a small-diameter piston fitted in the large-diameter cylinder chamber and the small-diameter cylinder chamber of the service cylinder so that they can integrally slide back and forth, and which are interlocked with this sliding movement. The present invention relates to a valve drive device that can drive other valves to open and close.

In general, for example, in oil shipping facilities, emergency shutoff valves are often installed in piping in case of emergencies such as fire or earthquakes, and there have been various types of valve drive devices for driving this type of shutoff valve. Are known.

For example, in conventional valve drive devices using a spring-return type piston-cylinder mechanism, as the capacity of the valve increases, a spring with greater spring force must be used, which makes it difficult to drive a large-capacity valve. It had disadvantages such as not being suitable for

In addition, for example, a valve driving device configured to store working fluid in an accumulator (pressure accumulator) in preparation for an emergency, and to operate the valve by supplying the working fluid in the pressure accumulator tank in case of an emergency, is a valve driving device that is configured to operate the valve by supplying the working fluid in the pressure accumulator tank in case of an emergency. This accumulator requires incidental equipment such as solenoid valves and piping, which not only complicates the configuration and increases manufacturing costs, but also causes the high-pressure working fluid in the accumulator to leak over time. This has disadvantages, such as the need for constant maintenance, which makes the device useless in an emergency.

The present invention opens and closes the valve by integrally displacing the large-diameter piston and small-diameter piston fitted in the large-diameter cylinder chamber and the small-diameter cylinder chamber of the stepped cylinder, and also creates a reverse valve between the small-diameter cylinder chamber and the switching valve. By providing a stop valve and configuring the small-diameter cylinder chamber to always keep working fluid at a predetermined pressure closed, the valve can not only be opened and closed whenever necessary, but can also be used in situations where, for example, the working fluid supply source becomes inoperable. It is an object of the present invention to provide a valve driving device which can urgently open and close a valve using working fluid in a small-diameter cylinder chamber even when the supply pressure has decreased, thereby eliminating the above-mentioned drawbacks.

The configuration for this purpose includes a cylinder having a pair of large-diameter and small-diameter cylinder chambers, and a cylinder fitted into the large-diameter cylinder chamber and the small-diameter cylinder chamber so as to be slidable within a predetermined area, respectively, and a working fluid supplied into the corresponding cylinder chambers. a large-diameter and small-diameter piston that constantly displaces integrally with each other while one pushes the other; a working fluid supply source that supplies compressible working fluid to the large-diameter and small-diameter cylinder chambers; and at least the working fluid supply source. It is provided between the large-diameter cylinder chamber and can be switched by an external signal to selectively communicate the large-diameter cylinder chamber with the working fluid supply source or the atmosphere, and when the working fluid supply source is normal, this - In the switching mode, working fluid is supplied to the large-diameter cylinder chamber, and the large-diameter and small-diameter pistons are slid in the direction of the small-diameter cylinder chamber by a difference in pressing force based on a difference in cross-sectional area between the large-diameter and small-diameter cylinder chambers. and, in another switching mode, a switching valve that communicates the large diameter cylinder chamber with the atmosphere and slides the large diameter and small diameter pistons toward the large diameter cylinder chamber by the pressure of the working fluid in the small diameter cylinder chamber; Provided between a working fluid supply source and the small-diameter cylinder chamber, allowing the supply of working fluid from the working fluid supply source into the small-diameter cylinder chamber, and constantly blocking the supplied working fluid into the small-diameter cylinder chamber. If the supply of working fluid from the working fluid supply source becomes impossible, regardless of the switching mode of the switching valve, the working fluid in the small diameter cylinder chamber will cause the large diameter and small diameter pistons to The check valve slides toward the cylinder chamber, and the large-diameter and small-diameter pistons are brought into an activated state and a non-activated state in response to the switching and sliding movements toward the small-diameter cylinder chamber and the large-diameter cylinder chamber, respectively. It consists of a valve.

Next, one example thereof will be explained.

FIGS. 1 and 2 are schematic vertical cross-sectional views of an embodiment of the valve driving device according to the present invention when the valve is opened and when the valve is closed, respectively.

In FIGS. 1 and 2, a shutoff valve 1 connects a valve 3, such as a ball valve, provided in a supply pipe 2 for oil, etc., to a valve drive device 4.
It is configured to be driven to open and close by.

The valve driving device 4 includes a pair of pistons 5 and 6 having a large diameter and a small diameter.
The piston-cylinder mechanism 7 includes a four-way electromagnetic switching valve 8 that controls the supply and discharge of working air to and from the piston-cylinder mechanism 7, and a check valve 9 that constitutes the main part of the present invention.

The cylinder 10 of the piston-cylinder mechanism 7 has a large-diameter cylinder chamber 11 and a small-diameter cylinder chamber 12, and the large-diameter piston 5 and the small-diameter piston 6 are slidable within the cylinder chambers 11 and 12 over predetermined distances, respectively. It is fitted in.

A rod 13 is connected to the left end surface of the small diameter piston 6 in the figure, and this rod 13 is connected to the rotating valve shaft 3a of the valve 3 via a rotating arm 14.

The four-way electromagnetic switching valve 8 has four ports: a supply port 8s, an exhaust port 8e, and output ports 80□, 80□, and the supply port 8s is connected to an air source 15 as a working fluid supply source. The exhaust port (8e) is open to the atmosphere.

The output port 8o1 is connected to the large diameter cylinder chamber 11 via a pipe 16, and the output port 802 is connected to the small diameter cylinder chamber 12 via a pipe 17.

The check valve 9 is provided in the pipe 17 and prevents air from flowing backward from the small diameter cylinder chamber 12 to the four-way electromagnetic switching valve 8.

A valve 18 is provided in the middle of a pipe 17 connecting the check valve 9 and the small diameter cylinder chamber 12.

This valve 18 opens as necessary, and the small diameter cylinder chamber 12
The working air inside can be exhausted to the outside.

First, before opening the valve 3, the four-way electromagnetic switching valve 8 is de-energized, the output port 802 is communicated with the supply port 8s, and working air from the air source 15 is supplied into the small diameter cylinder chamber 12.

Here, since a check valve 9 is provided between the small diameter cylinder chamber 12 and the four-way electromagnetic switching valve 8, once the small diameter cylinder chamber
The working air supplied into the cylinder chamber 2 does not flow back toward the four-way electromagnetic switching valve 8, and the working air is supplied to the small diameter cylinder chamber 12.
This results in a state shown in FIG. 2.

Next, when feeding fluid such as oil into the pipe 2, the four-way electromagnetic switching valve 8 is energized and excited.

As a result, the output port 80□ of the switching valve 8 is connected to the supply boat 8S, and the output port 80° is connected to the exhaust port 8e. supplied to

At this time, air at a constant pressure is already supplied into the small diameter cylinder chamber 12 as described above, but since the pressure receiving area of the large diameter piston 5 is larger than the pressure receiving area of the small diameter piston 6, the large diameter piston 5 is displaced to the left in the figure from the state shown in FIG. 1 while pushing the small-diameter piston 6 to the stepped portion of the cylinder 10 that is at the sliding limit position, resulting in the state shown in FIG.

When the large-diameter piston 5 is displaced to the sliding limit position on the left side of the figure as shown in Fig. 1, the valve shaft 3a has been rotated by a predetermined angle, and the valve 3 is accordingly fully opened. .

If it becomes necessary to shut off the piping 2 in the operating state where the valve 3 is fully open, the four-way electromagnetic switching valve 8 is de-energized.

As a result, the four-way electromagnetic switching valve 8 switches, and the output capo 1"
802 is connected to the supply port 8s, and the output port 8o1 is connected to the exhaust port 8e. As a result, the working air in the large diameter cylinder chamber 11 is discharged to the atmosphere via the exhaust port 8e, and the small diameter piston 6 and the large The diameter piston 5 is displaced to the right in the figure by the pressure of the working air in the small diameter cylinder chamber 12 and returns to the state shown in FIG. 2, and the valve 3 is closed at high speed and becomes inoperative.

In this way, the valve driving device 4 can close or open the valve 3 at any time as needed by cutting off the power to the four-way electromagnetic switching valve 8.

Furthermore, if the air source 15 becomes inoperable due to an emergency situation, for example, the valve drive device 4 is cut off from the supply of operating air via the four-way electromagnetic switching valve 8.
Since working air at a constant pressure is always present in the small diameter cylinder chamber 12, the valve driving device 4 can drive the valve 3 to close by itself, regardless of the operation of the air source 15.

In this way, even if the air source 15 becomes inoperable, the valve drive device 4 can drive the valve 3 to close using the working air blocked in the small-diameter cylinder chamber 12, and therefore operates like a conventional valve drive device. There is no need for a complicated structure such as fitting a spring with a large spring force into the cylinder or separately providing a pressure accumulating tank or the like as an auxiliary air source.

Further, in the above embodiment, the valve drive device 4 is configured to close the valve 3 to put it in a non-operating state in an emergency, for example.
By changing the connection between the valve drive device 4 and the valve 3, it is also possible to configure the valve in an emergency by opening the valve and putting it in a non-operating state.

Further, the valves that are driven to open and close by the valve driving device 4 are not limited to ball valves, but may also be other types such as butterfly valves or cock valves.

As mentioned above, the valve drive device according to the present invention constantly blocks the working fluid in the small-diameter cylinder chamber by the check valve provided between the working fluid supply source and the small-diameter cylinder chamber, so it is difficult to supply the working fluid in an emergency. When the power supply fails and becomes inoperable, the blocking fluid in the small diameter cylinder chamber of the switching mode of the switching valve can drive both pistons to put the valve in the inoperable state, thus eliminating the need for the conventional spring return type piston. There is no need for a complicated structure such as fitting a spring into a cylinder like in a valve drive device using a cylinder mechanism, or a complicated structure such as providing a separate pressure accumulation tank as an auxiliary fluid supply source in case of an emergency. It is possible to reliably put the valve in a non-operating state with an extremely simple configuration, which improves safety.Also, the blocked state of the working fluid in the small diameter cylinder chamber can be prevented through the check valve when the working fluid supply source is normal. Since it is only necessary to supply the working fluid through the cylinder, the work of closing the fluid can be done very easily. Also, since the small diameter cylinder and the large diameter cylinder always slide together, the structure and operation are simple, and maintenance is also easy. It has the following features.

[Brief explanation of the drawing]

1 and 2 are schematic vertical cross-sectional views of an embodiment of the valve driving device according to the present invention when the valve is opened and when the valve is closed, respectively. 1...Shutoff valve, 3...Valve, 4...
...Valve drive device, 5... Large diameter piston, 6...
...Small diameter piston, 8...Four-way electromagnetic switching valve, 9...Check valve, 11...Large diameter cylinder chamber, 12...Small diameter Cylinder chamber, 15... Air source, 17... Piping.

Claims (1)

[Scope of utility model registration request] a cylinder having a pair of cylinder chambers of a large diameter and a small diameter;
A large-diameter and a small-diameter piston are fitted into the large-diameter cylinder chamber and the small-diameter cylinder chamber so as to be slidable over a predetermined area, respectively, and are constantly displaced integrally with each other while one pushes the other by the working fluid supplied to the corresponding cylinder chamber. a working fluid supply source that supplies a compressible working fluid to the large-diameter and small-diameter cylinder chambers; The diameter cylinder chamber can be selectively communicated with the working fluid supply source or the atmosphere, and when the working fluid supply source is normal, the working fluid is supplied to the large diameter cylinder chamber in the negative switching mode. and the small-diameter piston is slid in the direction of the small-diameter cylinder chamber by the difference in pressing force based on the difference in cross-sectional area between the large-diameter and small-diameter cylinder chambers, and in another switching mode, the large-diameter cylinder chamber is communicated with the atmosphere and the above-mentioned a switching valve that slides the large-diameter and small-diameter pistons toward the large-diameter cylinder chamber by the pressure of the working fluid in the small-diameter cylinder chamber; and a switching valve that is provided between the working fluid supply source and the small-diameter cylinder chamber to supply the working fluid. When the working fluid is allowed to be supplied from the source into the small diameter cylinder chamber and the supplied working fluid is always blocked in the small diameter cylinder chamber, and the supply of working fluid from the working fluid supply source becomes impossible. Regardless of the switching mode of the switching valve, a check valve that slides the large diameter and small diameter pistons toward the large diameter cylinder chamber by the closed working fluid in the small diameter cylinder chamber; A valve driving device comprising a valve that is brought into an operating state and a non-operating state in response to the switching and sliding of the piston toward the small-diameter cylinder chamber and the large-diameter cylinder chamber, respectively.