JPH02287233A - Differential pressure measuring apparatus - Google Patents

Abstract

PURPOSE:To achieve a smaller size and a lighter weight with a switching of an input circuit by turning a rotary valve by integrating a differential pressure measuring device part and a three-way valve while a different pressure sensor section is supported in the air being separated from a base block with a lead pipe. CONSTITUTION:A differential pressure sensor section 1 is supported in the air being separated from a base block 4 with a lead pipe 2. Normally, as connec tion ports 43 and 44 communicate with each other, a measuring pressure is applied from the left and right of a body 11 and a measuring diaphragm is displaced by a differential pressure of the measuring pressure. With the displace ment thereof, electrostatic capacitances of a fixed electrode and the measuring disphragm change differentially to obtain an electrical signal output correspond ing to the differential pressure. To adjust zero point of the apparatus with the equalization of both measuring inputs of the apparatus, a rotary equalization valve 5 is turned to cut communication with a connection hole 44. Thus, a connection hole 43 is made to communicate with the side of a pressure receiving chamber 41 of the connection hole 44 thereby achieving a smaller size and a lighter weight.

Description

[Detailed description of the invention] <Industrial application field> The present invention relates to a differential pressure measuring device.

More specifically, the present invention relates to an input circuit of a differential pressure measuring device.

<Prior Art> FIG. 6 is a diagram illustrating the configuration of a conventional example of a flow rate measurement system using an orifice that has been commonly used.

In the figure, A is a conduit through which the measurement fluid flows.

B is an orifice provided in conduit A.

C is a conduit attached to conduit A upstream or downstream of orifice B. C1 is a main valve that opens and closes the conduit.

D is a three-way valve connected to conduit C. Dl is a stop valve provided on the three-way valve, and D2 is a pressure equalization valve.

E is a differential pressure measuring device connected to a three-way valve.

<Problems to be Solved by the Invention> However, in such a device, the three-way valve and the differential pressure measuring device "11.E" are separate bodies, and mutual piping is required.In addition, the device is complicated. This makes the device smaller and lighter.
Unable to reduce costs.

The present invention solves this problem.

The purpose of the present invention is to reduce costs by reducing size and weight, eliminating the need for parts such as piping, making it easy to switch input circuits, reducing static pressure span fluctuations, and making the sensor part non-grounded. An object of the present invention is to provide a differential pressure measuring device whose electric circuit can be simplified.

Means for Solving the Problems To achieve this object, the present invention provides a block-shaped body, an internal chamber provided inside the body and formed of opposing spherical surfaces, and a measuring pressure introduced into the internal chamber. A measurement diaphragm that functions as a movable electrode; a fixed electrode provided on the wall of the inner chamber opposite the measurement diaphragm via an insulator; a block-shaped housing; an internal space in which the main body is housed with a gap therebetween, and a communication provided in the main body and the housing, each having one end connected to the measurement chamber, one midway communicating with the internal space, and the other end opening to the outside of the housing. a differential pressure sensor section having a hole, a pressure impulse tube whose one end is connected to the other end of the communication hole via an insulator and which guides the measurement pressure, and a pressure receiving block to which the other end of the pressure impulse tube is respectively fixed. , a seal diaphragm provided on the outer surface of the pressure receiving block and forming a seal chamber communicating with the pressure receiving block and the impulse pipe; and a base block having a recess to which the pressure receiving block is attached and forming the seal diaphragm and the pressure receiving chamber. , two connection holes provided in the base block, one end communicating with the pressure receiving chamber and the other end opening to the outside as a pressure receiving connection port, and communication provided in the base block and provided on the circumferential surface of the rotary valve body. A groove normally communicates one of the connection holes, and when adjusting the zero point, the communication groove is rotated to disconnect communication between the one connection hole and the pressure receiving chamber side of the one connection hole and the other connection hole. This is a differential pressure measuring device comprising a rotary pressure equalizing valve that communicates with the rotary pressure equalizing valve.

In the above configuration, since the connection holes are usually in communication with each other, measurement pressure is applied from the left and right sides of the main body, and the measurement diaphragm is displaced by the differential pressure between the measurement pressures. The displacement of the measuring diaphragm differentially changes the capacitance between the fixed electrode and the measuring diaphragm, and an electrical signal output corresponding to the differential pressure is obtained.

To equalize the constant inputs on both sides of the device and adjust the zero point of the device, rotate the communication groove provided on the circumference of the rotary valve body to disconnect communication between one of the connection holes and connect the other connection hole. The zero point of the device is adjusted after communicating the pressure-receiving chamber side with the other side of the connection hole.Also, the main body is placed in the internal cavity of the housing, and one measuring pressure is applied from the outside of the main body. There is.

In addition, the sensor part is configured to be a non-grounded surface.

Hereinafter, a detailed explanation will be given based on examples.

<Embodiment> FIG. 1 is an explanatory diagram of the main part configuration of an embodiment of the present invention, and FIG. 2 is a perspective view of FIG. 1.

In the figure, 1 is a differential pressure sensor section.

11 is a block-shaped main body as shown in FIG.

111 is a body made of ceramics.

112 is a metal ring provided around the outer periphery of the body 111.

12 is an internal chamber provided in the main body 11 and made of opposing spherical surfaces.

Reference numeral 13 denotes a measuring diaphragm which divides the internal chamber 12 into two measuring chambers 14 and 15 and functions as a moving electrode.

Fixed electrodes 131 and 132 are provided on the wall of the internal chamber 12 facing the measurement diaphragm 13 via the body 111 which is an insulator.

16 is a block-shaped housing, as shown in FIG.

Reference numeral 161 denotes an internal space provided in the housing 16 and housing the main body 11 with a gap therebetween.

17 is provided in the main body 11 and the housing 16, and a measurement chamber 14
．． 15 , one end is connected to the internal cavity, and the other end is a communication hole that opens to the outside of the housing 16 .

Reference numeral 2 denotes a pressure guide tube whose one end is connected to the other end of the communication hole 17 via an insulator, and which guides the measurement pressure. In this case, the body 111 is made of ceramics.

Reference numeral 3 designates pressure receiving blocks to which the other ends of the pressure guiding pipes 2 are respectively fixed.

A seal diaphragm 31 is provided on the outer surface of the pressure receiving block 3 and constitutes a seal chamber 32 that communicates with the pressure receiving block 3 and the pressure guiding pipe 2.

4 is a seal diaphragm 3 to which a pressure receiving block 3 is attached.
1 and a recess 42 forming a pressure receiving chamber 41.

Reference numerals 43 and 44 designate two connection holes provided in the base block 4, one end communicating with the pressure receiving chamber 41 and the other end opening to the outside as a pressure receiving connection port.

In this case, the connection hole 43 is connected to the high pressure side, and the connection hole 44 is connected to the low pressure side.

5 is provided in the base block 4 as shown in FIG. 4, and normally passes through 44 connection holes through a communication groove 52 provided on the circumferential surface of the rotary valve body 51, and when adjusting the zero point,
The communication groove 52 is rotated to disconnect the connection hole 44 from the connection hole 4.
This is a rotary type pressure equalizing valve that communicates between the pressure receiving chamber 4211IJ of No. 4 and the connection hole 43.

6 is a cover attached to the base block 4, covering the differential pressure sensor section 1, as shown in FIG.

Reference numeral 61 denotes a printed board unit attached to the cover 6 and having electronic components attached thereto.

101.102 is the measurement room 14.15. This is a sealed liquid that is sealed in two chambers consisting of the pressure impulse pipe 2 and the seal chamber 32. In this case, silicone oil is used.

In the above configuration, since the connection holes 43 and 44 are normally in communication with each other, measurement pressure is applied from the left and right sides of the main body 11, and the measurement diaphragm 13 is displaced by the difference in the measurement pressures. As the measurement diaphragm 13 is displaced, the capacitance between the fixed electrodes 133 and 134 and the measurement diaphragm 13 changes differentially, and an electrical signal output corresponding to the differential pressure is obtained.

To equalize the constant inputs on both sides of the device and adjust the zero point of the device, as shown in FIG. The communication is cut off and the pressure receiving chamber 42 (I! Pressure is applied from the outside of the main body 11.

In addition, the sensor part is configured to be a non-grounded surface.

As a result, (1) Since the main body of the differential pressure measuring device and the three-way valve can be integrated, there is no need for bolts, main body flanges, brackets, etc. for installation, making it possible to reduce size, weight, and cost.

(2) Piping between the main body of the differential pressure measuring device and the three-way valve becomes unnecessary.

(3) The differential pressure sensor section 1 is separated from the base block 4 by the impulse tube 2 and supported in the air, so even if the fluid to be measured is at a high temperature, it can be measured without being affected by the temperature of the fluid to be measured. A device with a wide temperature range is obtained.

(4) Switching the input circuit can be done by simply rotating the main body 51 of the rotary valve.

(5) Since the main body 11 is disposed in the internal space 161 of the housing 16, and one measurement pressure is applied from the outside of the main body 11, a static pressure with little variation in span can be obtained.

(6) Since one end of the impulse tube 2 is connected to the sensor section through an insulator, the sensor section can be made into a non-grounded structure, and the electric circuit can be simplified.

In the above-mentioned embodiment, the rotary type pressure equalizing valve 5 was described as being manually operated, but it goes without saying that it may be a remote type valve using a solenoid valve or the like.

<Effects of the Invention> As explained above, the present invention comprises a block-shaped main body, an internal chamber provided inside the main body and made of opposing spherical surfaces, and the internal chamber divided into two measurement chambers into which measurement pressure is introduced. A measuring diaphragm functioning as a moving electrode; a fixed electrode provided on the wall of the internal chamber opposite the measuring diaphragm via an insulator; and a communication hole provided in the main body and the housing, each having one end connected to the measurement chamber, one midway communicating with the internal cavity, and the other end opening to the outside of the housing. A differential pressure sensor section, a pressure impulse tube whose one end is connected to the other end of the communication hole through an insulator and which guides the measured pressure, a pressure receiving block to which the other end of the pressure impulse tube is fixed, and the pressure receiving block. a seal diaphragm provided on the outer surface of the pressure receiving block and forming a seal chamber communicating with the pressure receiving block and the pressure impulse pipe; a base block having a recess to which the pressure receiving block is attached and forming a pressure receiving chamber with the seal diaphragm; Two connection holes are provided in the base block, one end of which communicates with the pressure receiving chamber, and the other end opens to the outside as a pressure receiving connection port, and a communication groove provided in the base block that is not provided on the circumferential surface of the rotary valve body. A rotary rotary that connects one of the connection holes and, when adjusting the zero point, rotates the communication groove to disconnect the one of the connection holes and communicates the pressure receiving chamber side of the one of the connection holes with the other of the connection holes. A differential pressure measuring device was constructed which included a type pressure equalizing valve.

As a result, (1) Since the main body of the differential pressure measuring device and the three-way valve can be integrated, there is no need for bolts, main body flanges, brackets, etc. for installation, making it possible to reduce size, weight, and cost.

(2) Piping between the main body of the differential pressure measuring device and the three-way valve becomes unnecessary.

(3) The differential pressure sensor part is separated from the base block by a pressure impulse tube and is supported in the air, so even if the fluid to be measured is at high temperature, it is not affected by the temperature of the fluid to be measured and is within the measurable temperature range. A wide device is obtained.

(4) Switching the input circuit can be done with a single touch, as the rotary valve body only needs to be moved at the same time.

(5) The main body is placed in the internal cavity of the housing, and one measurement pressure is applied from the outside of the main body, so
A product with less static pressure span fluctuation can be obtained.

(6) Since one end of each of the impulse tubes is connected to the sensor section via an insulator, the sensor section can be made into a non-grounded structure, and the electric circuit can be simplified.

Therefore, according to the present invention, costs can be reduced by reducing size and weight, eliminating the need for parts such as piping, etc., making it easy to switch input circuits, reducing static pressure span fluctuations, and making the sensor section non-grounded. Accordingly, it is possible to realize a differential pressure measuring device whose electric circuit can be simplified.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram of the main part configuration of an embodiment of the present invention, FIG.
FIGS. 3, 4, and 5 are explanatory diagrams of the main part configuration of FIG. 1, and FIG. 6 is an explanatory diagram of the configuration of a conventional example that has been generally used. 1... Differential pressure sensor section, 101, 102. ... Filled liquid, 11 ... Main body, 12 ... Internal chamber, 13 ... Measurement diaphragm, 131, 132 ... Fixed electrode, 14.
15...Measurement chamber, 16...Housing, 161...
・Internal space, 17... Communication hole, 2... Impulse pipe, 3.
...Pressure block, 31...Seal diaphragm, 3
2... Seal chamber, 4... Base block, 41...
・Pressure receiving chamber, 42... recess, 43.44... connection hole,
5... Rotary pressure equalization valve, 51... Rotary valve body, 52... Communication groove, 6... Cup (, 61... Printed board unit.

Claims (1)

[Claims] A block-shaped main body, an internal chamber provided inside the main body consisting of opposing spherical surfaces, and a measuring diaphragm functioning as a moving electrode that is divided into two measuring chambers into which measuring pressure is introduced, and a measuring diaphragm facing the measuring diaphragm. a fixed electrode provided on the wall surface of the internal chamber via an insulator, a block-shaped housing, an internal cavity provided in the housing and containing the main body with a gap therebetween, and a fixed electrode provided in the main body and the housing with a space therebetween for the measurement. a differential pressure sensor portion including a communication hole having one end connected to the chamber, one end communicating with the internal cavity, and the other end opening to the outside of the housing; and one end of the communication hole being insulated at the other end of the communication hole. A pressure-receiving block to which the other ends of the pressure-receiving tubes are fixed, and a seal provided on the outer surface of the pressure-receiving block and communicating with the pressure-receiving block and the pressure-receiving tube. a seal diaphragm constituting a chamber; a base block to which the pressure receiving block is attached and having a concave portion constituting the seal diaphragm and the pressure receiving chamber; and a base block provided in the base block with one end communicating with the pressure receiving chamber and the other end receiving pressure externally. There are two connection holes that open as connection ports and a communication groove provided in the base block and on the circumferential surface of the rotary valve body. Normally, one of the connection holes is connected, and the communication groove is rotated during zero point adjustment. A differential pressure measuring device comprising: a rotary pressure equalizing valve that moves to disconnect communication between the one connection hole and communicate between the pressure receiving chamber side of the one connection hole and the other connection hole.