JPH11175166A - Pressure reducing valve with flow rate measuring function - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pressure reducing valve with flow rate measuring function with which a flow rate can be also measured with a simple structure. SOLUTION: A piston 14 is provided with a semispherical space 33. Pressure sensors 32 and 34 are attached into the space 33. A coil spring 12 is arranged at the lower part of a main valve element 7 while being energized in valve closing direction. Pressure added to the piston 14 is detected by the pressure sensors 32 and 34 and converted into a load so that the valve aperture of the main valve element 7 balanced with the displacement load of the coil spring 12 can be calculated and a downward flow rate can be calculated from the pressure difference of primary and secondary sides.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pressure reducing valve which is attached to a piping system for steam, compressed air, liquid or the like to maintain a fluid pressure at an outlet side, that is, a secondary side of the valve at a predetermined set pressure. The present invention relates to a device having a function of measuring a flow rate flowing down a valve.

[0002]

2. Description of the Related Art A conventional pressure reducing valve capable of measuring a flow rate is disclosed, for example, in JP-A-63-45614. This is provided with a displacement detector that detects the displacement of the main valve body of the pressure reducing valve, detects the displacement of the main valve body, that is, the opening degree with this displacement detector, and flows down the pressure reducing valve based on this valve opening degree. The flow rate can be measured.

[0003]

SUMMARY OF THE INVENTION In the above prior art,
A displacement detector for detecting the opening of the main valve element must be provided, and there is a problem that the mechanism of the pressure reducing valve becomes complicated.

Accordingly, an object of the present invention is to provide a pressure reducing valve having a flow rate measuring function capable of measuring a flow rate with a simple structure.

[0005]

Means for Solving the Problems According to the means of the present invention taken in order to solve the above-mentioned problems, a fluid pressure on the outlet side of the valve, that is, on the secondary side is detected by a pressure detecting means, and the pressure detecting means is connected to the pressure detecting means. The valve portion is opened and closed via a pressure responsive member, and the inlet side of the valve, that is, the high pressure fluid on the primary side is supplied to or stopped from the secondary side, and the valve portion of the pressure reducing valve for maintaining the fluid pressure on the secondary side at a predetermined value. In a valve capable of calculating the flow rate flowing down the pressure reducing valve from the opening degree and the pressures on the primary side and the secondary side, a valve section connected to the pressure responsive member is arranged, and the valve section is closed by an elastic member. Primary pressure detecting means is provided to urge the valve in the valve direction and detect the primary pressure applied to the pressure responsive member, and when the valve section opens and the fluid flows down to the secondary side, the pressure is increased. Pressure responsive to impinging fluid pressure detecting means for detecting pressure generated by colliding with the response member Attached to the member, a calculation unit that converts the detected pressure from the collision fluid pressure detection unit and the primary side pressure detection unit into a load and calculates the opening degree of the valve unit from the offset relationship with the elastic force of the elastic member. The flow rate flowing down the pressure reducing valve is calculated from the opening degree of the valve unit and the primary and secondary pressures by the arithmetic unit.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS As is well known in the art, the flow rate flowing down a valve is a constant based on the type of fluid flowing down k, the pressure difference between the primary and secondary sides of the valve is ΔP, and the valve opening is Is a parameter
Flow rate: Q = k, where Cv is the capacity coefficient specific to the valve
· Cv · △ P1 / 2 It can be calculated by the formula.

[0007] ΔP is determined from the pressures on the primary side and the secondary side, and the valve is determined from the offset relationship between the pressure from the primary pressure detecting means and the collision fluid pressure detecting means of the pressure responsive member and the elastic force of the elastic member. Cv is obtained by calculating the opening degree of the part,
The flow rate Q flowing down the pressure reducing valve can be calculated using the above equation.

When a coil spring, for example, is used as the elastic member, the pressure responsive member opens the valve portion by the load that urges the valve portion in the valve closing direction by the coil spring and the primary pressure applied to the pressure responsive member. The load due to the valve and the load due to the fluid force applied to the pressure responsive member by the fluid flowing down after the valve is opened are balanced, that is, the valve opening is determined by canceling out. Therefore, when the pressure receiving area of the pressure responsive member is constant, the load at which the pressure responsive member opens the valve portion is calculated by detecting the applied pressure, and the coil spring is bent by the amount corresponding to this load. In addition, the displacement of the coil spring, that is, the opening of the valve portion can be calculated.

[0009]

FIG. 1 shows an overall configuration diagram of a pressure reducing valve having a flow rate measuring function according to the present invention. An inlet 2 and an outlet 3 are provided in the pressure reducing valve body 1, and the inlet 2 is connected to a steam source (not shown) by a pipe 30.
A pressure sensor 31 as pressure detection means for detecting the primary pressure of the valve is attached to the conduit 30. On the other hand, a pressure sensor 5 for detecting a secondary pressure is attached to a conduit 4 provided at the outlet 3.

A main valve body 7 as a valve portion and a main valve port 8 are provided on the pressure reducing valve main body 1 via a swirling blade 6. At the lower part of the swirling blade 6, a float 9 is disposed in a float cover 10 in a free state. A float valve 11 is attached below the float 9. A coil spring 12 as an elastic member is arranged below the main valve body 7 as a valve section, and a slide bar 13 is provided so that the main valve body 7 is slidably mounted vertically. The coil spring 12 is disposed so as to urge the main valve body 7 in the valve closing direction, that is, in the main valve port 8 side.

A piston 14 as a pressure responsive member, a pilot valve 15, and a diaphragm 16 as pressure detecting means are arranged above the main valve body 7. The lower portion of the piston 14 is formed in a hemispherical shape, and a space 33 is provided in the hemispherical portion.
4 is attached. Each of the pressure sensors 32 and 34 uses a strain gauge and is attached to a thin plate portion forming a hemispherical portion, and an upper pressure sensor 32 detects a primary pressure applied to the piston 14 to detect a primary pressure. The means,
The lower pressure sensor 34 forms a collision fluid pressure detecting means.
The pressure applied to the piston 14 is detected by each of the pressure sensors 32 and 34.

Although not shown, the pressure sensors 32 and 34 are connected to a controller 22 to be described later by communicating a signal line from the upper part of the piston 14 to the outside of the main body 1. In this embodiment, an example is shown in which only one lower pressure sensor 34 is mounted, but a plurality of pressure sensors may be mounted on the hemispherical portion.

Above the diaphragm 16, there are provided a coil spring 17 for setting pressure, an adjusting screw 18 for adjusting the amount of compression of the coil spring 17, and a motor 19 for moving the adjusting screw 18 up and down while rotating. When the adjusting screw 18 moves up and down due to the rotation of the motor 19, and the amount of compression of the coil spring 17 changes, the spring force pressing the diaphragm 16 downward changes, and the secondary pressure of the pressure reducing valve is reduced to a predetermined pressure. It is set to a value.

The inlet 2 and the pilot valve 15 communicate with each other through a communication passage 25, the pilot valve 15 communicates with the upper space of the piston 14 through a communication passage 26, and the diaphragm 16
Is communicated with the outlet 3 through a communication passage 21. Exit 3
The pressure on the side, that is, the secondary pressure of the pressure reducing valve is transmitted to the lower part of the diaphragm 16 as the pressure detecting means by the communication path 21 and is automatically maintained at a pressure value balanced with the spring force of the coil spring 17.

The primary pressure of the pressure reducing valve is detected by a pressure sensor 31, the secondary pressure is detected by a pressure sensor 5, and
The pressure on the primary side applied to the piston 14 as a pressure responsive member is detected by a pressure sensor 32, and the impinging fluid pressure applied to the piston 14 by the fluid flow flowing down when the main valve body 7 opens is a pressure sensor 34. Are sent to the controller 22.

Although not shown, the controller 22 is provided with a storage unit, and calculates the flow rate: Q from the relationship between the capacity coefficient Cv and the opening of the main valve element 7 and Cv and ΔP. formula,
In addition, an expression for calculating the opening of the main valve element 7 corresponding to the spring force of the coil spring 12 based on the pressure values detected by the pressure sensors 32 and 34 is stored, and the flow rate is calculated from the relationship of the storage unit. An operation unit is provided. The calculated flow value is displayed on the display unit 23 of the controller 22.

Although the high-pressure and high-speed steam flows down the main valve body 7, the main valve port 8, and the lower surface of the piston 14, the pressure applied to the piston 14 changes due to the flow of the fluid.
The flow rate can be accurately calculated by detecting the pressure at any time by a pressure sensor 34 attached below the hemispherical portion of the piston 14.

The set pressure of the pressure reducing valve increases as the adjusting screw 18 is tightened downward, and the pressure on the secondary side, that is, the outlet 3 side can be maintained at a higher pressure. There is a specific correlation between the screwing amount of the adjusting screw 18 and the set pressure on the secondary side. From this relationship, when the set pressure on the secondary side can be reliably grasped based on the screwing amount of the adjusting screw 18. Can eliminate the pressure sensor 5 on the secondary side.

[0019]

The displacement of the valve, that is, the opening of the valve, is detected by detecting the pressure on the primary side applied to the piston as the pressure responsive member and the pressure applied to the piston by the fluid flowing down from the valve section. A pressure reducing valve capable of measuring a flow rate with a simple structure can be obtained without the need for a device.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional configuration diagram showing an embodiment of a pressure reducing valve with a flow rate measurement function of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main body 2 Inlet 3 Outlet 5 Pressure sensor 7 Main valve body 14 Piston 15 Pilot valve body 16 Diaphragm 17 Coil spring 18 Adjusting screw 19 Motor 22 Controller 31 Pressure sensor 32 Pressure sensor 33 Space 34 Pressure sensor

Claims (1)

[Claims] 1. A pressure detecting means for detecting a fluid pressure on an outlet side, that is, a secondary side of a valve, and opening and closing a valve portion through the pressure detecting means and a pressure responsive member. From the opening degree of the valve portion of the pressure reducing valve and the pressure on the primary side and the secondary side, which supply or stop the fluid to the secondary side and maintain the fluid pressure on the secondary side at a predetermined value, the flow rate flowing down the pressure reducing valve is determined. In those that can be calculated, a valve portion connected to the pressure responsive member is arranged, and the valve portion is urged by an elastic member in a valve closing direction,
A primary pressure detecting means for detecting a primary pressure applied to the pressure responsive member is provided, and the fluid collides with the pressure responsive member when the valve portion is opened and the fluid flows down to the secondary side. A collision fluid pressure detecting means for detecting pressure is attached to the pressure responsive member, and the pressure detected by the collision fluid pressure detecting means and the primary side pressure detecting means is converted into a load to cancel out the elastic force of the elastic member. A flow rate measuring function characterized by providing a calculation unit for calculating the opening degree of the valve unit from the calculation unit, and calculating the flow rate flowing down the pressure reducing valve from the opening degree of the valve unit and the primary and secondary pressures by the calculation unit. With pressure reducing valve.