Gas quantity sensor and gas relay having the same

Abstract

A gas quantity sensor and a gas relay equipped with the gas quantity sensor belong to the field of gas detection technology, and particularly relate to a gas quantity sensor and a gas relay equipped with the gas quantity sensor. The present invention provides a gas quantity sensor with good measuring effect and a gas relay equipped with the gas quantity sensor. The present invention comprises a top pressure-guiding pipe and a liquid level pressure-guiding pipe of the gas quantity sensor, characterized in that the top pressure-guiding pipe is placed above the liquid level pressure-guiding pipe, the pressure value P1 at the pressure-guiding port of the top pressure-guiding pipe is the pressure value of the closed environment, the pressure value P2 at the pressure-guiding port of the liquid level pressure-guiding pipe is the sum of the ambient pressure and the liquid level pressure, the pressure generated by the liquid level is P, P=P2-P1; the top pressure-guiding pipe is connected to the first pressure sensing port of the sensor sensing transmission component, and the liquid level pressure-guiding pipe is connected to the second pressure sensing port of the sensor sensing transmission component.

Description

Technical Field

[0001] The present invention belongs to the technical field of gas detection, and in particular relates to a gas quantity sensor and a gas relay equipped with the gas quantity sensor. Background Art

[0002] Used for accurate detection of gas quantity in transformer gas relay. The characteristics of gas quantity detection in gas relay are small range and high precision. Currently, no existing technology can meet the above requirements for gas quantity detection in gas relay. A new type of gas quantity sensor is invented to meet these requirements. Summary of the invention

[0003] The present invention aims at solving the above problems and provides a gas quantity sensor with good measuring effect and a gas relay equipped with the gas quantity sensor.

[0004] To achieve the above object, the present invention adopts the following technical scheme, which includes a top pressure-guiding pipe and a liquid level pressure-guiding pipe of a gas volume sensor, characterized in that the top pressure-guiding pipe is placed above the liquid level pressure-guiding pipe, the pressure value P1 at the pressure-guiding port of the top pressure-guiding pipe is the pressure value of the closed environment, the pressure value P2 at the pressure-guiding port of the liquid level pressure-guiding pipe is the sum of the environment pressure and the liquid level pressure, the pressure generated by the liquid level is P, P=P2-P1;

[0005] The top pressure-inducing pipe is connected to the first pressure-inducing port of the sensor sensing transmission component, and the liquid surface pressure-inducing pipe is connected to the second pressure-inducing port of the sensor sensing transmission component.

[0006] As a preferred solution, the top pressure-guiding pipe and the liquid level pressure-guiding pipe of the present invention both adopt L-shaped pipes, the upper end of the front vertical pipe of the top pressure-guiding pipe is the top pressure-guiding port, and the upper end of the front vertical pipe of the liquid level pressure-guiding pipe is the liquid level pressure-guiding port.

[0007] As another preferred scheme, the sensor sensing transmission component described in the present invention includes a sensor sensing element, a sensor circuit board and a power module. The top pressure-inducing tube is connected to the first pressure sensing port of the sensor sensing element, and the liquid level pressure-inducing tube is connected to the second pressure sensing port of the sensor sensing element; the signal input port of the sensor circuit board is connected to the pressure sensing component of the sensor sensing element; and the power output port of the power module is connected to the power output port of the sensor circuit board.

[0008] As another preferred embodiment, the sensor sensing element 4 of the present invention includes a first single crystal silicon pressure sensor and a second single crystal silicon pressure sensor. The first single crystal silicon pressure sensor diaphragm is connected to the top pressure-inducing tube 2, and the second single crystal silicon pressure sensor diaphragm is connected to the liquid level pressure-inducing tube 18.

[0009] As another preferred solution, the sensor inductive transmission component of the present invention is arranged in the sensor housing, and the top pressure-guiding pipe and the liquid surface pressure-guiding pipe are arranged at the front end of the sensor housing.

[0010] As another preferred solution, a wiring board is provided on the sensor housing of the present invention, and the detection signal output port and the power supply port of the sensor inductive transmission component are connected to the wiring board.

[0011] As another preferred solution, the wiring board of the present invention is provided with a mains connection terminal and a signal output terminal.

[0012] As another preferred solution, the sensor housing of the present invention comprises a sensor front housing and a sensor rear housing, the front part of the sensor sensing element is arranged in the opening of the sensor front housing, a sealing plate is arranged at the front end of the opening, and the top pressure-guiding pipe and the liquid level pressure-guiding pipe pass through the sealing plate and are connected to the sensor sensing element;

[0013] An opening is provided in the middle of the rear housing of the sensor, and the periphery of the wiring board is connected to the periphery of the rear housing of the sensor at the front end of the opening through fasteners;

[0014] A horizontal strip-shaped opening is arranged at the lower end of the sensor circuit board, and a threaded hole is arranged on the sensor front shell at the side of the opening of the sensor front shell corresponding to the horizontal strip-shaped opening.

[0015] As another preferred solution, a countersunk groove is provided on the sensor sensing element of the present invention at the connection position with the pressure-guiding tube, a boss is provided at the sealing plate corresponding to the countersunk groove, and an O-ring is provided between the countersunk groove and the boss.

[0016] As another preferred embodiment, a junction box cover is provided at the rear end of the middle opening of the sensor rear shell body of the present invention, the outer periphery of the junction box cover is connected to the sensor rear shell body outside the periphery of the rear end of the opening through fasteners, a sealing ring placement groove is provided at the periphery of the rear end of the opening, and a sealing ring is provided in the sealing ring placement groove.

[0017] As another preferred solution, the sensor front shell of the present invention is provided with connection holes around its periphery, and the outer contour of the sensor rear shell has four corners with missing corners, which correspond to the connection holes.

[0018] The gas relay provided with a gas quantity sensor of the present invention comprises a gas relay body, and is characterized in that a gas quantity sensor for detecting the gas quantity inside the gas relay is arranged on the gas relay body.

[0019] As another preferred solution, the gas quantity sensor of the present invention is arranged at the viewing window of the gas relay body.

[0020] As another preferred scheme, the sensor circuit board described in the present invention includes a single-chip microcomputer, a signal conversion circuit, a communication interface and a current control circuit. The information transmission port of the single-chip microcomputer is respectively connected to the signal conversion circuit, the communication interface, the current control circuit, the linear constant measurement range constant transmitter configuration, the measurement calibration device or the button.

[0021] As another preferred solution, the sensor sensing element of the present invention adopts a single crystal silicon sensor.

[0022] As another preferred solution, the single chip microcomputer of the present invention adopts STC8H1K28 chip U1, and pin 31 of U1 is connected to connector J12; pin 32 of U1 is connected to connector J13.

[0023] As another preferred solution, the current control circuit of the present invention adopts XTR111 chip U2, pin 2 of U2 is respectively connected to the emitter of PNP transistor Q1 and one end of resistor R25, the other end of R25 is respectively connected to the drain of P-channel MOS tube Q2 and the base of Q1, the gate of Q2 is respectively connected to the collector of Q1 and pin 3 of U2, the source of Q2 is respectively connected to one end of capacitor C4 and one end of resistor R28, the other end of C4 is grounded, the other end of R28 is connected to the anode of diode D2, and the cathode of D2 is connected to connector J11;

[0024] Pin 7 of U2 is grounded through resistor R29, pins 10 and 11 of U2 are grounded, pin 6 of U2 is connected to one end of capacitor C2 and one end of resistor R26 respectively, the other end of C2 is grounded, the other end of R26 is connected to one end of capacitor C3 and one end of resistor R27 respectively, the other end of C3 is grounded, and the other end of R27 is connected to pin 7 of U1.

[0025] Secondly, the communication interface of the present invention adopts a 485 chip, and pin 1 of the 485 chip is connected to pin 19 of U1 and pin 1 of U1 respectively, and pins 2 and 3 of the 485 chip are connected to pin 18 of U1 and one end of a resistor R33 respectively, and the other end of R33 is grounded;

[0026] Pin 5 of the 485 chip is connected to GND, pin 6 of the 485 chip is connected to one end of resistor R34 and one end of resistor R32 respectively, the other end of R34 is connected to +5V, the other end of R32 is connected to the cathode of Zener tube D5, the cathode of Zener tube D4 and pin 1 of connector J1 respectively, pin 7 of the 485 chip is connected to one end of resistor R30 and one end of resistor R31 respectively, the other end of R31 is connected to the cathode of Zener tube D3 and pin 2 of J1 respectively, the other end of R30 is connected to the anode of D3, GND and the anode of D4 respectively.

[0027] In addition, the power module of the present invention adopts a 7805 chip VR1, and the Vin port of VR1 is respectively connected to pin 5 of the connector J5, +24V, the positive electrode of capacitor C6, the positive electrode of capacitor C7, and one end of capacitor C10, and the negative electrode of C6 is respectively connected to GND, the negative electrode of C7, the other end of C10, the GND port of VR1, the negative electrode of capacitor C8, and one end of capacitor C9, and the other end of C9 is respectively connected to +5V, the positive electrode of C8, and the Vout port of VR1.

[0028] The invention has beneficial effects.

[0029] The gas volume sensor of the present invention uses the pressure generated by different liquid level heights to detect the liquid level, thereby obtaining the value of the gas volume above the liquid level, which is beneficial to small-range and high-precision liquid level measurement.

[0030] The pressure measurement of the present invention is detected by the top pressure inlet (pressure value is represented by P1) and the liquid surface pressure inlet (pressure value is represented by P2). P1 is the pressure value of the closed environment, P2 is the sum of the environmental pressure and the liquid surface pressure, and the pressure generated by the liquid surface (pressure value is represented by P). The formula is expressed as: P=P2-P1; at this time, the P value is not affected by the closed environmental pressure; making the measurement more accurate. With the P value, you can know the current height of the liquid level, and thus know the amount of gas in the gas relay. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The present invention is further described below in conjunction with the accompanying drawings and specific implementation methods. The protection scope of the present invention is not limited to the following description.

[0032] Figure 1 It is an exploded view of the gas quantity sensor of the present invention.

[0033] Figure 2 It is a schematic diagram of the structure of the gas volume sensor of the present invention.

[0034] Figure 3 It is a schematic diagram of the structure of the gas volume sensor of the present invention from another angle.

[0035] Figure 4 It is a cross-sectional view of the gas quantity sensor of the present invention.

[0036] Figure 5 It is a schematic diagram of the structure of a gas relay with a gas quantity sensor according to the present invention.

[0037] Figure 6 It is a schematic diagram of the structure of the existing gas relay of the present invention.

[0038] Figure 7 It is a circuit principle block diagram of the present invention.

[0039] Figures 8 to 16 It is a circuit schematic diagram of the present invention.

[0040] In the figure, 1 is an opening, 2 is a top pressure-inducing tube, 3 is a sensor front shell, 4 is a sensor sensing element, 5 is a power module, 6 is a mains terminal, 7 is a sensor rear shell, 8 is a sealing ring, 9 is a junction box cover, 10 is a signal output terminal, 11 is a terminal board, 12 is a sensor circuit board, 13 is a horizontal strip opening, 14 is a threaded hole, 15 is a missing corner, 16 is a connecting hole, 17 is a sealing plate (the sealing plate 17 and the sensor front shell 3 can adopt an integrated structure), 18 is a liquid level pressure-inducing tube, 19 is a countersunk groove, 20 is an O-ring, 21 is a boss, 22 is a gas volume sensor, 23 is a gas relay body, 24 is a window, 25 is a threaded hole in the front shell, 26 is a threaded hole in the rear shell, and 27 is a connecting screw for the wire box cover. DETAILED DESCRIPTION

[0041] As shown in the figure, the present invention includes a top pressure-inducing pipe 2 of a gas volume sensor 22 and a liquid level pressure-inducing pipe 18. The top pressure-inducing pipe 2 is placed above the liquid level pressure-inducing pipe 18. The pressure value P1 at the pressure-inducing port of the top pressure-inducing pipe 2 is the pressure value of the closed environment. The pressure value P2 at the pressure-inducing port of the liquid level pressure-inducing pipe 18 is the sum of the environmental pressure and the liquid level pressure. The pressure generated by the liquid level is P, and P=P2-P1.

[0042] The top pressure-inducing pipe 2 is connected to the first pressure-inducing port of the sensor sensing transmission component, and the liquid surface pressure-inducing pipe 18 is connected to the second pressure-inducing port of the sensor sensing transmission component.

[0043] Oil density: ρ, unit is g / cm³;

[0044] Oil unit area s;

[0045] The height from the upper pressure inlet (the pressure inlet of the top pressure inlet pipe 2) to the lower pressure inlet (the pressure inlet of the liquid surface pressure inlet pipe 18) is: H, and the height from the liquid surface to the lower pressure inlet is: h;

[0046] P1=F1 / s, P2=F2 / s;

[0047] F1 and F2 represent the force acting on the unit area S (F1 is the force acting on the unit area S by the pressure in the container, and F2 is the force acting on the unit area S by the pressure in the gas relay and the pressure generated by the oil.

[0048] F2 / s-F1 / s=ρ×h, the unit area of ​​pressure is 1cm², so s=1cm² (unit area of ​​P1 and P2)

[0049] F2 -F1 =ρ×h=P2-P1

[0050] h=(F2-F1) / ρ=(P2-P1) / ρ,

[0051] The unit of pressure P1 and P2 is g / cm²; the unit of pressure F1 and F2 is g.

[0052] h changes linearly, so in actual use the analog output or digital output corresponding to the h value can be calibrated; adjust the liquid level to the highest state (gas volume is 0), at this time the analog output of the h value is set to 4mA or the digital output value is 0, adjust the liquid level to the lowest state (gas volume is 300), at this time the analog output is 20mA or the digital output value is 300.

[0053] The present invention can detect the amount of gas change per unit time and determine whether the situation is urgent.

[0054] The position of the pressure inlet of the top pressure inlet pipe 2 may be consistent with the initial liquid level.

[0055] The top pressure-guiding pipe 2 and the liquid level pressure-guiding pipe 18 are both L-shaped pipes, the upper end of the front vertical pipe of the top pressure-guiding pipe 2 is the top pressure-guiding port, and the upper end of the front vertical pipe of the liquid level pressure-guiding pipe 18 is the liquid level pressure-guiding port.

[0056] The sensor sensing transmission component includes a sensor sensing element 4, a sensor circuit board 12 and a power module 5. The top pressure-inducing tube 2 is connected to the first pressure sensing port of the sensor sensing element 4, and the liquid level pressure-inducing tube 18 is connected to the second pressure sensing port of the sensor sensing element 4; the signal input port of the sensor circuit board 12 is connected to the pressure sensing component of the sensor sensing element 4 (the pressure sensing component can adopt a single crystal silicon pressure sensor diaphragm, and the sensor circuit board 12 amplifies the weak signal output by the diaphragm and processes it into a standard signal output, such as: analog quantity, communication digital quantity); the power output port of the power module 5 is connected to the power output port of the sensor circuit board 12.

[0057] The sensor inductive transmission component is arranged in the sensor housing, and the top pressure-guiding pipe 2 and the liquid surface pressure-guiding pipe 18 are arranged at the front end of the sensor housing.

[0058] The sensor housing is provided with a wiring board 11 , and the detection signal output port and the power supply port of the sensor inductive transmission component are connected to the wiring board 11 .

[0059] The wiring board 11 is provided with a mains connection terminal 6 and a signal output terminal 10 (the output signal may be 4-20mA or MODBUS).

[0060] The sensor housing includes a sensor front housing 3 and a sensor rear housing 7. The front part of the sensor sensing element 4 is arranged in the opening 1 of the sensor front housing 3. A sealing plate 17 is arranged at the front end of the opening 1. The top pressure-guiding pipe 2 and the liquid level pressure-guiding pipe 18 pass through the sealing plate 17 and are connected to the sensor sensing element 4.

[0061] An opening is provided in the middle of the sensor rear housing 7, and the periphery of the wiring board 11 is connected to the periphery of the sensor rear housing 7 at the front end of the opening through fasteners. The power module can be fixed on the sensor rear housing 7 in a tight fit, and then encapsulated with epoxy resin after all are assembled.

[0062] A horizontal strip-shaped opening 13 is provided at the lower end of the sensor circuit board 12 , and a threaded hole 14 is provided on the sensor front housing 3 at the side of the opening of the sensor front housing 3 corresponding to the horizontal strip-shaped opening 13 .

[0063] The sensor sensing element 4 is provided with a countersunk groove 19 at the connection position with the pressure-inducing pipe, and the sealing plate 17 is provided with a boss 21 corresponding to the countersunk groove 19, and an O-ring 20 is provided between the countersunk groove 19 and the boss 21. The countersunk groove 19 and the boss 21 cooperate with each other for positioning, and the O-ring 20 plays a sealing role.

[0064] A junction box cover 9 is provided at the rear end of the middle opening of the sensor rear shell 7. The outer periphery of the junction box cover 9 is connected to the sensor rear shell 7 outside the periphery of the rear end of the opening through fasteners. A sealing ring placement groove is provided around the rear end of the opening, and a sealing ring 8 is provided in the sealing ring placement groove.

[0065] The periphery of the sensor front housing 3 is provided with connecting holes 16 , and the four corners of the outer contour of the sensor rear housing 7 are notched 15 structures, and the notched 15 structures correspond to the connecting holes 16 .

[0066] like Figure 1 As shown, the sensor front shell 3 and the sensor rear shell 7 can be connected through a threaded hole 25, a rear shell threaded hole 26 and a front and rear shell connecting screw. The rear shell threaded hole 26 is a T-shaped hole. The large-diameter end of the T-shaped hole at the rear serves as a threaded hole for connecting the wire box cover connecting screw 27, and the small-diameter end of the T-shaped hole at the front serves as a through hole for connecting the front and rear shell screws. A step extending inward is provided at the through hole, and the head of the front and rear shell connecting screw abuts against the step.

[0067] The gas relay provided with the gas quantity sensor 22 of the present invention comprises a gas relay body 23 , and is characterized in that the gas relay body 23 is provided with the gas quantity sensor 22 for detecting the gas quantity inside the gas relay.

[0068] The gas quantity sensor 22 is arranged at the window 24 of the gas relay body 23. The window 24 of the conventional gas relay can be removed, and the gas quantity sensor 22 can be installed at the position of the original window 24. In this way, the performance and function of the original relay will not be affected in any way, and the gas relay can work independently of the original gas relay. It is very convenient to modify the gas relay installed on the equipment without the gas quantity remote transmission function (remove a window 24 and install the gas quantity sensor 22 to complete).

[0069] The sensor circuit board 12 includes a single-chip microcomputer, a signal conversion circuit, a communication interface and a current control circuit. The information transmission port of the single-chip microcomputer is respectively connected to the signal conversion circuit, the communication interface, the current control circuit, the measurement calibration device or a button (the HART standard protocol can be used to calibrate the sensor through a 4-20mA port).

[0070] The sensor sensing element 4 includes a first single crystal silicon pressure sensor and a second single crystal silicon pressure sensor. The first single crystal silicon pressure sensor diaphragm L is connected to the top pressure-inducing tube 2 , and the second single crystal silicon pressure sensor diaphragm H is connected to the liquid surface pressure-inducing tube 18 .

[0071] The single chip microcomputer adopts STC8H1K28 chip U1, and the 31st pin of U1 is connected to the connector J12; the 32nd pin of U1 is connected to the connector J13. J12 and J13 are connected to the circuit output of sensor diaphragm L and sensor diaphragm H, that is, the differential pressure signal input.

[0072] The current control circuit adopts XTR111 chip U2, and the 2nd pin of U2 is respectively connected to the emitter of PNP transistor Q1 and one end of resistor R25, and the other end of R25 is respectively connected to the drain of P-channel MOS tube Q2 and the base of Q1, and the gate of Q2 is respectively connected to the collector of Q1 and the 3rd pin of U2, and the source of Q2 is respectively connected to one end of capacitor C4 and one end of resistor R28, and the other end of C4 is grounded, and the other end of R28 is connected to the anode of diode D2, and the cathode of D2 is connected to connector J11 (J11 is the analog output port). The analog quantity output by the current control circuit J11 is to convert the measured differential pressure value into the standard analog quantity 4-20mA output.

[0073] Pin 7 of U2 is grounded through resistor R29, pins 10 and 11 of U2 are grounded, pin 6 of U2 is connected to one end of capacitor C2 and one end of resistor R26 respectively, the other end of C2 is grounded, the other end of R26 is connected to one end of capacitor C3 and one end of resistor R27 respectively, the other end of C3 is grounded, and the other end of R27 is connected to pin 7 of U1.

[0074] The communication interface uses a 485 chip, and pin 1 of the 485 chip is connected to pin 19 of U1 and pin 1 of U1 respectively, and pins 2 and 3 of the 485 chip are connected to pin 18 of U1 and one end of resistor R33 respectively, and the other end of R33 is grounded;

[0075] Pin 5 of the 485 chip is connected to GND, pin 6 of the 485 chip is connected to one end of resistor R34 and one end of resistor R32 respectively, the other end of R34 is connected to +5V, the other end of R32 is connected to the cathode of Zener tube D5, the cathode of Zener tube D4 and pin 1 of connector J1 respectively, pin 7 of the 485 chip is connected to one end of resistor R30 and one end of resistor R31 respectively, the other end of R31 is connected to the cathode of Zener tube D3 and pin 2 of J1 respectively, the other end of R30 is connected to the anode of D3, GND and the anode of D4 respectively.

[0076] The signal conversion circuit comprises a first LM324 chip, a second LM324 chip and a third LM324 chip, wherein pin 1 of the first LM324 chip is connected to pin 31 of U1, pin 3 of the first LM324 chip is respectively connected to pin 1 of the second LM324 chip and pin 3 of the second LM324 chip, and pin 2 of the first LM324 chip is respectively connected to pin 1 of the third LM324 chip and pin 2 of the third LM324 chip;

[0077] Pin 2 of the second LM324 chip is connected to pin 2 of the PC10D chip (Nanjing Wotian PC10D silicon piezoresistive core can be selected), and pin 3 of the third LM324 chip is connected to pin 5 of the PC10D chip.

[0078] The power module 5 adopts a 7805 chip VR1, and the Vin port of VR1 is respectively connected to the 5th pin of the connector J5 (J5 is connected to the AC 220 to DC 24V power module), +24V, the positive electrode of capacitor C6, the positive electrode of capacitor C7, and one end of capacitor C10, and the negative electrode of C6 is respectively connected to GND, the negative electrode of C7, the other end of C10, the GND port of VR1, the negative electrode of capacitor C8, and one end of capacitor C9, and the other end of C9 is respectively connected to +5V, the positive electrode of C8, and the Vout port of VR1.

[0079] It can be understood that the above specific description of the present invention is only used to illustrate the present invention and is not limited to the technical solutions described in the embodiments of the present invention. Those skilled in the art should understand that the present invention can still be modified or replaced by equivalents to achieve the same technical effects; as long as the use requirements are met, they are within the protection scope of the present invention.

Claims

1. A gas volume sensor, comprising a gas volume sensor top pressure lead pipe and a liquid level pressure lead pipe, characterized in that The top pressure-inducing pipe is placed above the liquid surface pressure-inducing pipe. The pressure value P1 at the pressure-inducing port of the top pressure-inducing pipe is the pressure value of the closed environment. The pressure value P2 at the pressure-inducing port of the liquid surface pressure-inducing pipe is the sum of the environmental pressure and the liquid surface pressure. The pressure generated by the liquid surface is P, P=P2-P1; Oil density: ρ; oil unit area s; height from the pressure inlet of the top pressure inlet pipe to the pressure inlet of the liquid surface pressure inlet pipe: H; height from the liquid surface to the lower pressure inlet: h; P1=F1 / s, P2=F2 / s; F1 is the force exerted by the pressure in the container on the unit area s, and F2 is the force exerted by the pressure in the gas relay and the pressure generated by the oil on the unit area s; F2 / s-F1 / s=ρ×h, F2 / s-F1 / s=ρ×h=P2-P1, h=(F2 / s-F1 / s) / ρ=(P2-P1) / ρ, h is a linear change; during use, the analog output or digital output corresponding to the h value is calibrated; The top pressure-inducing pipe is connected to the first pressure-inducing port of the sensor sensing transmission component, and the liquid surface pressure-inducing pipe is connected to the second pressure-inducing port of the sensor sensing transmission component; The sensor induction transmission component is arranged in the sensor housing, and the top pressure-guiding pipe and the liquid surface pressure-guiding pipe are arranged at the front end of the sensor housing; The sensor housing is provided with a wiring board, and the detection signal output port and the power supply port of the sensor induction transmission component are connected to the wiring board; The wiring board is provided with a mains connection terminal and a signal output terminal, and the output signal is 4-20mA or MODBUS; The sensor sensing transmission component includes a sensor sensing element, a sensor circuit board and a power module, the top pressure-inducing pipe is connected to the high-pressure sensing port of the sensor sensing element, and the liquid surface pressure-inducing pipe is connected to the low-pressure sensing port of the sensor sensing element; the signal input port of the sensor circuit board is connected to the pressure sensing component of the sensor sensing element; the power output port of the power module is connected to the power output port of the sensor circuit board; The sensor circuit board includes a single-chip microcomputer, a signal conversion circuit, a communication interface and a current control circuit. The information transmission port of the single-chip microcomputer is respectively connected to the signal conversion circuit, the communication interface, the current control circuit, the linear constant measurement range constant transmitter configuration, the measurement calibration device or the button; the communication interface adopts a 485 chip.

2. The gas volume sensor according to claim 1, characterized in that The top pressure-guiding pipe and the liquid surface pressure-guiding pipe are both L-shaped pipes, the upper end of the front vertical pipe of the top pressure-guiding pipe is the top pressure-guiding port, and the upper end of the front vertical pipe of the liquid surface pressure-guiding pipe is the liquid surface pressure-guiding port.

3. The gas volume sensor according to claim 1, characterized in that The sensor sensing element comprises a first single crystal silicon pressure sensor and a second single crystal silicon pressure sensor. The diaphragm of the first single crystal silicon pressure sensor is connected to the top pressure-inducing tube, and the diaphragm of the second single crystal silicon pressure sensor is connected to the liquid surface pressure-inducing tube.

4. The gas volume sensor according to claim 1, characterized in that The sensor housing comprises a sensor front housing and a sensor rear housing, the front part of the sensor sensing element is arranged in the opening of the sensor front housing, a sealing plate is arranged at the front end of the opening, and the top pressure-guiding pipe and the liquid level pressure-guiding pipe pass through the sealing plate and are connected to the sensor sensing element; An opening is provided in the middle of the rear housing of the sensor, and the periphery of the wiring board is connected to the periphery of the rear housing of the sensor at the front end of the opening through fasteners; A horizontal strip-shaped opening is arranged at the lower end of the sensor circuit board, and a threaded hole is arranged on the sensor front shell at the side of the opening of the sensor front shell corresponding to the horizontal strip-shaped opening.

5. The gas volume sensor according to claim 4, characterized in that A junction box cover is arranged at the rear end of the middle opening of the sensor rear shell, and the outer periphery of the junction box cover is connected to the sensor rear shell outside the periphery of the rear end of the opening through fasteners. A sealing ring placement groove is arranged around the rear end of the opening, and a sealing ring is arranged in the sealing ring placement groove.

6. A gas relay having a gas quantity sensor as claimed in any one of claims 1 to 5, comprising a gas relay body, characterized in that A gas quantity sensor for detecting the gas quantity inside the gas relay is arranged on the gas relay body.

7. The gas relay according to claim 6, characterized in that The gas quantity sensor is arranged at the viewing window of the gas relay body.

Images