JPH03163277A - Fluid controller - Google Patents

Abstract

PURPOSE:To stabilize the secondary side pressure and obtain a small-sized device by installing a cutoff valve, first and second control valves in a main passage, lowering the primary side pressure in two stages and controlling the second control valve by the secondary side pressure and the intermediate pressure. CONSTITUTION:In an ordinary state, a cut-off valve 4, the first and second control valve 5 and 6 are opened, and the gas supplied from an inlet 2a obtains a prescribed intermediate side pressure, passing through a port 4a and a port 5a. Further, a diaphragm 5c is moved vertically according to the primary side pressure by the control valve 5, and the intermediate side pressure is made constant. Then, the gas is controlled to a prescribed pressure through the passing through a port 6a. Since, at this time, the diaphragm 10b of a servoregulator 10 lowers, the intermediate side pressure is transmitted to a working pressure chamber 10h, and the diaphragm 6c is controlled i n the vertical direction, and the secondary side pressure is made constant. When the secondary side pressure increases abnormally, the cut-off valve 4 is closed, and safety is secured, and whole of the device can be made small-sized.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a fluid control device that controls the pressure and flow rate of fluid such as city gas.

[Conventional technology]

As a conventional fluid control device equipped with a shutoff valve and a control valve, there is one disclosed in Japanese Patent Publication No. 5B-45629, for example. In this conventional device, a shutoff valve and a control valve are slidably provided in one axial direction perpendicular to the direction of the main fluid passage, and a diaphragm chamber is provided that communicates with the secondary side of the main passage. By associating the diaphragm mechanism provided in this diaphragm chamber with the shutoff valve and the control valve, the control valve controls the secondary pressure and the shutoff valve controls the fluid flow when the secondary pressure reaches the upper limit or lower limit. The system also performs shutoff control. [Problems to be Solved by the Invention] In the conventional fluid control device described above, when the pressure ratio between the primary side pressure and the secondary side pressure is large, the effective diameter of the diaphragm of the control valve becomes very large. For this reason, it was inevitable that the overall size of the device would increase. In particular, in the case of medium-pressure supply equipment branched from the main pipe, such as gas supply lines to apartment complexes and condominiums, there are problems such as the desire for equipment that is compact and good-looking. there were.

This invention was made to solve the above-mentioned problems, and it is an object of the present invention to provide a fluid control device that is small in size, has a reliable shutoff function, and can improve safety.

[Means for Solving the Problems] A fluid control device according to the present invention includes a main passage provided with a cutoff valve section and first and second control valve sections, and a secondary side pressure and a first and second control valve section. Controlling the second control valve part by a servo regulator based on the intermediate side pressure between the valve parts, and detecting abnormally high pressure of the secondary side pressure,
The locking mechanism of the shutoff valve part is released to perform the shutoff operation. [Function] A predetermined secondary pressure can be stably obtained, the valve body and diaphragm of each valve part can have a small effective diameter, and abnormal high pressure can be reliably detected and shut off. The operation can be performed reliably. [Example] In the figure, l is the main body, 2 is the main fluid passage provided in the main body 1, and an inlet 2a through which fluid is input with primary pressure.
and an outlet 2b which is controlled to a predetermined secondary side pressure and outputted.
and has. This main passage 2 is provided with a mesh filter 3, a cutoff valve section 4, a first control valve section 5, and a second control valve section 6 from the port 2a toward the outlet 2b.

The shutoff valve section 4 includes a port 4a provided in the main passage 2, a valve body 4b that opens and closes the port 1-4a, a valve shaft 4C to which the valve body 4b is attached, and a valve body 4C that biases the valve body 4b in the closing direction. spring 4d
and a bellows seal 4e that seals the upper part of the valve shaft 4C. The first control valve section 5 is connected to the main passage 2
5a provided in the port 5a, a valve body 5b that controls the opening degree of the port 5a, a diaphragm 5C to which the valve body 5b is attached, and a direction in which the port 5a opens by applying a constant force to the diaphragm 5C (downward in the figure) It is composed of a spring 5d that biases the The second control valve section 6 includes a port 6a provided in the main passage 2, a valve body 6b that controls the opening degree of the bow 6a, a diaphragm 6C to which the valve body 6b is attached, and a diaphragm 6C.
A spring 6d biases the port 6a in the direction in which it closes. A passage 7 for detecting the pressure on the output side, that is, the secondary side, of the second control valve section 6 and the second control valve section 6
A passage 8 is provided to detect the pressure on the input side of the first control valve section 5, that is, on the output side (hereinafter referred to as the intermediate side), and a strainer 9 is provided at the entrance of the passage 8. ．． A servo regierator section 10 is provided for controlling the secondary side pressure based on the pressures detected in the passages 7.8. This servo regulator section 10 includes a first secondary pressure chamber 10a communicating with the passage 7, a diaphragm 10b provided in the first secondary pressure chamber 10a, and valve bodies 10c and 10d provided in the diaphragm 10b. and the first 2
A port 10e that communicates with the pressure chamber 10a and is opened and closed by the valve body 10c, a port 10f that communicates with the passage 8 and that is opened and closed by the valve body 10d, and a passage 10 that communicates with the valve body 10e, lOf.
g, a working chamber lOh that communicates with this passage 10g and is partitioned by the diaphragm 6C, and the diaphragm 1
It is composed of a spring 10i that urges 0b downward in the figure.

Further, a relief valve section 11 for the first abnormally high pressure of the secondary side pressure is provided. This relief valve part l1 includes a relief pressure chamber 11a communicating with the passage 7, a diaphragm llb provided in the relief pressure chamber 11a, a valve body 11c provided in the diaphragm llb, and an air outlet lid opened and closed by the valve body 11c. and a spring lie that urges the diaphragm llb downward.

An abnormal high pressure detection section l2 is provided for detecting a second abnormal high pressure of the secondary side pressure. This second abnormal high pressure detection section l2 includes a detection passage 12a led out from the first secondary pressure chamber 10a, and a second
a diaphragm 12c provided in the second secondary pressure chamber 12b, a valve element 12d provided in the diaphragm 12c, and a second secondary pressure chamber 12b opened and closed by the valve element 12d.
It is constituted by a bow 12e communicating with the next pressure chamber 12b and a spring 12f urging the diaphragm 12c downward. A shutoff valve driving section 13 for driving the shutoff valve section 4 is provided. This cutoff valve drive unit 13 is connected to the port 1
2e, a booster chamber 13b communicating with the passage 13a, a diaphragm 13c provided in the booster chamber 13b, a spring 13d biasing the diaphragm 13c to the left in the figure, and a spring 13d provided in the diaphragm 13c. The latch arm 13g has one end pivotally supported on one end of the shaft 13e and the other end is rotatably supported on the support shaft 13f, and a locking pawl 13h provided on the latch arm 13g. It is configured.

Next, the operation of the above configuration will be explained. This fluid control device has a flow rate of, for example, about 3000 MAQ from the inlet 2a.
After the intermediate pressure gas supplied at the next side pressure is lowered to an intermediate side pressure of about 1/10 by the first control valve section 5, the second control valve section 6 lowers the intermediate pressure gas to a predetermined secondary side pressure (for example, 210 mmAq
), which is taken out from the outlet 2b and supplied to a subsequent gas meter, etc. In a normal state, the valve element 4b of the cutoff valve section 4 opens the port 4a, and each valve element 5b of the first and second control valve sections 5 and 6 opens.
, 6b also open each port }5a, 6a to a predetermined opening degree. The gas supplied from the inlet 2a is transferred to the port 4a.
, and then through port 5a, resulting in a predetermined intermediate side pressure.

In the first control valve section 5, the opening degree is adjusted by moving the diaphragm 5C up and down by the urging force of the spring 5d according to the primary side pressure, and the intermediate side pressure is controlled to be substantially constant. Next, the gas is controlled to a predetermined pressure by passing through port 6a. At this time, the servo regulator part 10
The diaphragm 10b of is lowered, the valve body 10c closes the port lOe, and the valve body 10d opens the port lOf. Therefore, the intermediate side pressure detected in the passage 8 is transferred to the working pressure chamber t through Bau}10f and the passage Log.
oh, and in response to this, the diaphragm 6C is controlled up and down so that the secondary pressure is constant. When the secondary pressure increases, this pressure is transmitted to the first secondary pressure chamber 10a through the passage 7, which causes the diaphragm 10b to rise, the bow 10e to open, and the port 10f to close. Therefore, the pressure in the secondary pressure chamber 10a decreases, and this is transmitted to the working pressure chamber 10h through the port 10e and the passage 10g, so that the diaphragm 6
c increases, reducing the opening degree of bow 1-6a and lowering the secondary pressure.

Secondary pressure is abnormally high (e.g. 700111Aq)
Then, this abnormal pressure is transmitted from the first secondary pressure chamber 10a to the second secondary pressure chamber 12b through the passage 12a. This causes the diaphragm 12c to rise and the valve body 12d to open the port 12e. Therefore, the pressure in the second secondary pressure chamber 12b is transferred to the booster chamber 13 through the passage 13a.
This causes the diaphragm 13c to move to the right in the figure against the spring 13e, rotating the latch arm 13g clockwise. As a result, the engagement between the locking pawl 13h and the latch gear 13i is released, the valve shaft 4c is raised by the force of the spring 4d, and the valve body 4b closes the port 4a.
Cut off the gas flow.

The return of the shutoff valve section 4 after the shutoff operation is based on the safety of the secondary side or the absence of any abnormality in the device! This is done manually after approval.

If the secondary pressure is even more abnormally high (e.g. 750mIIIA)
q or more), this abnormally high pressure is transmitted from the passage 7 to the relief pressure chamber 11a, causing the diaphragm llb to rise and the valve body 11c to open the outlet lid, thereby blowing out the gas. Ru.

〔Effect of the invention〕

As described above, according to the present invention, the primary side pressure is reduced in two stages by providing the first and second control valve parts, so that the valve body and diaphragm used in each control valve part are The effective diameter of the control valve can also be small, and although it has two control valve sections and a shutoff valve section, the entire device can be made compact. Since the parts are precisely controlled, it is possible to stably obtain a predetermined secondary side pressure, and in the event of abnormally high pressure, the shutoff valve part can be reliably shut off to maintain safety.

[Brief explanation of the drawing]

The drawing is a sectional side view showing a fluid control device according to an embodiment of the present invention. 2 is a main passage, 4 is a shutoff valve part, 4a is a port, 4b is a valve body, 4C is a valve shaft, 4d is a spring, 5 is a first control valve part, 5a
is a port, 5b is a valve body, 5d is a spring, 6 is a second control valve part, 6a is a port, 6b is a valve body, 7 and 8 are passages for detection, 10a is a first secondary pressure chamber, 10b is the diaphragm,
IOc, 10d is a valve body, 10e, 10f is a port, 10
h is the working pressure chamber, l2 is the abnormal high pressure detection section, 13c
is a diaphragm, 13e is a shaft body, 13g is a latch arm, 13h is a locking pawl, and 13i is a latch gear.

Claims (2)

[Claims] (1) A shutoff valve part provided on the primary side of the main passage of fluid and having a valve body biased in the direction of closing the port; A first control valve section configured to control the opening degree of the port with an energized valve body, and a predetermined secondary side pressure disposed in the main passage next to the first control valve section. a second control valve section controlled to obtain a second control valve section, a passage for detecting the secondary side pressure, and an intermediate side pressure between the first control valve section and the second control valve section. a passage, a secondary pressure chamber to which the secondary pressure detected in the passage is transmitted, and a first pressure chamber that responds to the pressure of the secondary pressure chamber.
a response means, a switching means for switching between the pressure in the second pressure chamber and the intermediate pressure detected in the passage in accordance with the operation of the first response means, and a pressure obtained from the switching means; Abnormally high pressure is transmitted through a working pressure chamber that applies pressure to control the opening degree of the valve body of the second control valve section to the port, and an abnormally high pressure of the secondary side pressure that is detected through the secondary pressure chamber. a detection section, a second response means that responds to the detected pressure of the abnormal high pressure detection section, and a valve shaft provided with the valve body in the shutoff valve section, which engages so that the valve body holds the port in an open state. A fluid control device comprising: a locking mechanism configured to lock and release the lock by response of the second response means. (2) a third response means that reacts when the pressure detected in the passage for detecting the secondary pressure exceeds a predetermined value; and a blower that releases the secondary pressure in response to the third response means. The fluid control device according to claim 1, further comprising a valve body that opens the mouth.