JPH11175165A - 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 pressure sensor 32 is attached into an upper space 33 of a piston 14. A coil spring 12 is arranged at the lower part of a main valve element 7 while being energized in a valve closing direction. A pressure added to the piston 14 is detected by the pressure sensor 32 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 constant 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 opening and closing of the valve section of the pressure reducing valve that opens and closes the valve section through the pressure responsive member and supplies or stops the high pressure fluid on the primary side to the secondary side to maintain the fluid pressure on the secondary side at a predetermined value and the primary side And a valve that can calculate the flow rate flowing down the pressure reducing valve from the pressure on the secondary side, dispose a valve portion connected to the pressure responsive member, and urge the valve portion in the valve closing direction with an elastic member. Then, pressure detecting means for detecting the pressure applied to the pressure responsive member is provided, and the pressure detected by the pressure detecting means is converted into a load, and the opening degree of the valve unit is determined from the offset relationship with the elastic force of the elastic member. A calculation unit for calculation is provided, and the calculation unit calculates the opening degree of the valve unit and the primary side and the secondary side. It is intended for calculating the flow rate flowing down the pressure reducing valve from the side pressure.

[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 obtained from the pressures on the primary side and the secondary side, and the opening of the valve section is calculated from the offset relationship between the pressure from the pressure detecting means of the pressure responsive member and the elastic force of the elastic member. , And 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, a load that urges the valve portion in the valve closing direction by the coil spring and a load that causes the pressure responsive member to open the valve portion by the pressure applied to the pressure responsive member. Are balanced, that is, they cancel each other to determine the opening degree of the valve section. 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 a pressure detecting means for detecting the primary pressure 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. A pressure sensor 32 as pressure detection means is attached to a space 33 above the piston 14. Piston 14 with pressure sensor 32
The pressure applied to the is detected.

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 side communicates with the pilot valve 15 through a communication passage 25, the pilot valve 15 communicates with the space 33 through a communication passage 26, and the lower space 20 of the diaphragm 16.
Through the communication passage 21 with the outlet 3 side. The pressure on the outlet 3 side, that is, the pressure on the secondary side of the pressure reducing valve is transmitted to the lower part of the diaphragm 16 through 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
Space 3 added to piston 14 as pressure response member
The pressure of No. 3 is detected by the pressure sensor 32 and sent to the controller 22 respectively. Although not shown, the controller 22 is provided with a storage unit to provide a relationship between the capacity coefficient Cv and the opening of the main valve element 7, an equation for calculating the flow rate: Q from Cv and ΔP, and An arithmetic unit for calculating an opening degree of the main valve element 7 corresponding to the spring force of the coil spring 12 based on the pressure value detected by the pressure sensor 32 and calculating a flow rate from the relationship of the storage unit is provided. Provide. The calculated flow value is displayed on the display unit 23 of the controller 22.

When high-pressure steam flows down the main valve body 7, the main valve port 8, and the lower surface of the piston 14 at a high pressure, and the pressure applied to the piston 14 changes due to the flow of the fluid, an experiment must be performed in advance. The corresponding correction coefficient is obtained by
By adding to the flow rate formula: Q, the flow rate can be accurately calculated.

The pressure reducing valve increases the set pressure as the adjusting screw 18 is tightened downward, and can maintain the pressure on the secondary side, that is, the outlet 3 side, 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.

[0017]

By detecting the pressure applied to the piston as a pressure responsive member, a detector for detecting the displacement of the valve, that is, the valve opening is not required, and the pressure reducing valve can measure the flow rate with a simple structure. Can be obtained.

[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 Adjustment screw 19 Motor 22 Controller 31 Pressure sensor 32 Pressure sensor 33 Space

Claims (1)

[Claims] 1. A pressure detecting means detects a fluid pressure on an outlet side of a valve, that is, on a secondary side, and opens and closes a valve portion through the pressure detecting means and a pressure responsive member, so that a high pressure fluid on a primary side is discharged on a secondary side. The flow rate flowing down the pressure reducing valve can be calculated from the opening degree of the valve portion of the pressure reducing valve and the pressures on the primary side and the secondary side, which supply or stop to the secondary side and maintain the fluid pressure on the secondary side at a predetermined value. And a pressure detecting means for arranging a valve portion connected to the pressure responsive member, urging the valve portion with a resilient member in a valve closing direction, and detecting a pressure applied to the pressure responsive member. An arithmetic unit is provided for calculating the opening of the valve unit from the offset relationship with the elastic force of the elastic member by converting the detected pressure from the detecting means into a load, and the arithmetic unit is configured to calculate the opening of the valve unit and the primary side and the primary unit. A flow rate measuring device for calculating a flow rate flowing down a pressure reducing valve from a secondary pressure. Noble pressure reducing valve.