A gas absolute measurement sensor

Abstract

The application discloses a kind of absolute measurement sensor of gas, including air inlet structure, air outlet structure, measuring component and circuit component, air inlet structure is used for the gas to be detected into sensor and measuring component contact, air outlet structure is used for gas to be discharged sensor, circuit component is electrically connected with measuring component, measuring component includes thermosensitive element, compensation element and adjusting component, thermosensitive element is placed in the measuring chamber of sensor, compensation element is placed in the compensation chamber of sensor and is adjusted tightness by adjusting component;Adjusting component includes ratchet wheel and the driving member of driving ratchet wheel rotation, ratchet wheel is connected with one end of compensation element for slack compensation element;The application is driven ratchet wheel rotation by driving member in adjusting component, so that the slack of compensation element connected with ratchet wheel is tightened, so as to compensate the problem of sensor measurement error caused by the relaxation of thermosensitive element in measuring chamber due to long-term use work.

Description

Technical Field

[0001] This invention relates to the field of sensor technology, and in particular to a gas absolute measurement sensor. Background Technology

[0002] In my country's manufacturing processes, the purity of gaseous working fluids is crucial in many procedures. For example, in the industrial production of carbon dioxide, the concentrations of ammonia and hydrogen in the carbon dioxide cannot be too high, otherwise it could lead to an explosion. In the nuclear industry's uranium hexafluoride preparation process, the concentrations of hydrofluoric acid and air in the working fluid cannot be too high, as this would affect the uranium content. Gas concentration measurement technology is a critical link in ensuring the concentration of gaseous working fluids and preventing accidents. With the development and application of gas concentration sensors and related supporting equipment in my country, the independent research and development of key supporting components is an urgent goal to be achieved.

[0003] Existing gas concentration sensors, such as the combustible gas concentration sensor with patent number CN202122972235.5, solve the problem of dust prevention when not in use by shielding the detection chamber and effectively avoiding the impact of external dust on detection accuracy through the cooperation between the device body and protective components. However, during use, the thermistor wire will loosen over time, leading to larger measurement errors. Summary of the Invention

[0004] The purpose of this invention is to provide a gas absolute measurement sensor that solves the problem that the thermistor wire becomes loose over time during use, leading to large measurement errors.

[0005] This invention is implemented as follows: a gas absolute measurement sensor includes an inlet structure, an outlet structure, a measurement component, and a circuit component. The inlet structure is used for the gas to be detected to enter the sensor and contact the measurement component. The outlet structure is used for the gas to exit the sensor. The circuit component is electrically connected to the measurement component. The measurement component includes a thermistor, a compensation element, and an adjustment component. The thermistor is placed in the measurement chamber of the sensor, and the compensation element is placed in the compensation chamber of the sensor and its tightness is adjusted by the adjustment component.

[0006] The adjustment assembly includes a ratchet and a drive component that drives the ratchet to rotate. The ratchet is connected to one end of a compensation element for tightening or loosening the compensation element.

[0007] To ensure that the current-ampere performance of the thermistor is suitable for the sensor's measurement requirements, the heat dissipation of the compensation element is adjusted by adjusting the component. The drive in the adjustment component drives the ratchet to rotate, which tightens the compensation element connected to the ratchet, thereby compensating for the sensor measurement error caused by the relaxation of the thermistor in the measurement chamber due to long-term use.

[0008] The gas in the compensation chamber is a heavy gas that has been purged of air impurities, while the gas entering the working chamber is a heavy gas containing air impurities. When the resistance wire in the measuring assembly is heated by the power supply, its thermal conductivity changes proportionally to the thermal conductivity of the gas mixture entering the working and compensation chambers. The gas sensor bridge circuit exhibits an imbalance, and the output voltage value, which is proportional to the air impurity content, also changes accordingly.

[0009] The sensor of this invention is used to measure the absolute percentage content of light gases such as air and hydrogen fluoride in heavy industrial gases like uranium hexafluoride, and ammonia and hydrogen in carbon dioxide. It monitors the content of light impurity gases to ensure it is below specified values, thus meeting the requirements for safe production.

[0010] A further technical solution of the present invention is: the compensation element is connected in the compensation chamber through a connector, a resistive stress plate for measuring the tensile force of the compensation element is provided at the connection between the compensation element and the connector, the resistive stress plate is electrically connected to the controller, and the controller is electrically connected to the drive component.

[0011] A further technical solution of the present invention is that the driving component is a rotary drive motor.

[0012] The controller receives feedback from the strain gauge readings, which in turn controls a rotary drive motor to rotate and tighten the resistance wire of the compensation element, ensuring that the thermistor is adjusted to the optimal preload.

[0013] A further technical solution of the present invention is: the driving component is placed outside the compensation chamber, the driving component is a screw, and the screw passes through the ratchet to drive the ratchet to rotate.

[0014] A further technical solution of the present invention is: the adjustment assembly further includes a reversing limiting member, one end of which passes through the ratchet and is connected to the compensation chamber for fastening the ratchet.

[0015] Because the spiral wire forming the compensation element has low elasticity, it is equipped with a reverse limiter. After the adjustment is completed, the ratchet position is fixed by tightening the reverse limiter; this prevents the reverse adjustment of the compensation element or the reverse force caused by manual adjustment screws from affecting the resistance value of the resistance wire and thus affecting the accuracy of the sensor.

[0016] A further technical solution of the present invention is that the tension of the compensation element is 0.4-0.7N.

[0017] A further technical solution of the present invention is: the circuit assembly includes a zero-position corrector, a sliding resistor, and a gear mechanism. The zero-position corrector is connected to the gear mechanism through the sliding resistor. The movement of the sliding resistor is used to adjust the resistance of the part connected to the circuit. The gear mechanism is a multi-stage adjustment gear mechanism.

[0018] The resistance of the sensor circuit is adjusted by moving the sliding contact. The lower end of the sliding contact is connected to the first stage gear of the gear mechanism, which adjusts the resistance of the circuit in multiple stages.

[0019] A further technical solution of the present invention is as follows: the gear mechanism includes a first gear, a secondary adjustment knob, a second gear, a third gear, a tertiary adjustment knob, a fourth gear, a fifth gear, a sixth gear, and a fourth adjustment knob. The first gear and the second gear mesh. The sliding resistor and the secondary adjustment knob are connected via the first gear and the second gear. The third gear is coaxially connected to the second gear and meshes with the fourth gear. The secondary adjustment knob and the tertiary adjustment knob are connected via the third gear and the fourth gear. The fourth gear and the fifth gear are coaxially connected, and the fifth gear is a helical gear. The sixth gear is a meshing gear and meshes with the fifth gear. The fourth adjustment knob is connected to the sixth gear.

[0020] This invention employs a multi-stage adjustment mechanism, overcoming the drawbacks of long adjustment times and low production efficiency associated with manual adjustments. Manual zero-point calibration can take over 10 minutes, while the multi-stage adjustment gear mechanism reduces this time to less than 1 minute. Addressing the common issue of inconvenience in adjusting on the circuit board, coarse adjustments are made directly on the zero-point calibrator, replacing precise adjustments via the circuit board. The number of adjustment stages can be appropriately increased or decreased according to accuracy requirements to ensure the sensor's measurement accuracy.

[0021] A further technical solution of the present invention is: the transmission ratio between the first gear and the second gear is 5:1, the transmission ratio between the third gear and the fourth gear is 2:1, and the transmission ratio between the fifth gear and the sixth gear is 5:1.

[0022] A further technical solution of the present invention is: both the air intake structure and the air outlet structure include a connector nozzle, a pulse tube and a damping hollow ball. One end of the pulse tube is connected to the connector nozzle and the other end is connected to the measurement chamber or compensation chamber of the sensor. The damping hollow ball is movable inside the pulse tube and has circular intercepting holes evenly distributed throughout in three dimensions.

[0023] A further technical solution of the present invention is that the pulse tube in the air intake structure is connected to the measuring chamber through the central groove.

[0024] When gas flows in and out of the sensor, the airflow passes through the obstruction orifice and the gap between the small ball and the tapered tube, flowing from the outside into the working chamber. The obstruction is achieved by the gravity of the small ball itself, the variation in the gap between the inner diameter of the tapered tube and the outer diameter of the small ball, and the size of the obstruction orifice, adapting to the flow velocity of the gas being measured. This ensures that the airflow velocity along the thermistor element is not too high and remains uniform during gas exchange within the working chamber, controlling sufficient heat exchange between the airflow and the thermistor wire. For different test gases and different airflow velocities, by coordinating parameters such as the density, wall thickness, outer diameter, obstruction orifice diameter, number and distribution of obstruction orifices, and the taper of the pulse tube, a uniform and stable flow velocity of the incoming gas entering the working chamber is achieved. This makes signal acquisition more accurate and stable, reduces the impact of sudden changes in flow rate on the output signal, and improves the accuracy and precision of the sensor measurement.

[0025] The beneficial effects of the present invention are as follows: In order to make the current-ampere performance of the thermistor suitable for the measurement requirements of the sensor, the present invention adjusts the heat dissipation of the compensation element by adjusting the adjustment component. The ratchet is driven to rotate by the driving component in the adjustment component, so that the compensation element connected to the ratchet is tightened, thereby compensating for the sensor measurement error caused by the relaxation of the thermistor in the measurement chamber due to long-term use.

[0026] This invention ensures that the resistance wire is adjusted to the optimal preload through an adjustable component, and prevents human error or reverse force from affecting the resistance wire's resistance value and thus the sensor's accuracy through a reversing limiting component, guaranteeing that the resistance value and sensor accuracy error is less than 1%. The zero-position corrector material solves the problem of unstable resistance value caused by poor contact. The multi-stage adjustment mode in this invention solves the problem of long adjustment time and reduced production efficiency, can replace circuit board for precise adjustment, simplifies the adjustment steps, ensures the sensor's measurement accuracy, and controls the output error within 2mV. The air inlet and outlet structures are equipped with damping hollow ball components with different intercepting orifice diameters, which improves the single-peak signal into a hump shape, reduces the impact of signal acquisition accuracy and sudden changes in flow rate on the output signal, and improves the accuracy and precision of sensor measurements. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of a gas absolute measurement sensor provided by the present invention;

[0028] Figure 2 This is a bridge circuit schematic diagram of the sensor detection circuit of the present invention; wherein R1-4 are resistance wires and R5 is a sliding resistor;

[0029] Figure 3 This is a simplified diagram of the gear mechanism of the present invention;

[0030] Figure 4 Provided by the present invention Figure 1 View from direction B in the middle.

[0031] Reference numerals: 1: Damping hollow ball; 2: Compensating element; 3: Compensating chamber; 4: Measuring chamber; 5: Housing; 6: Central groove; 7: Aviation plug; 8: Connector nozzle; 9: Fabric-reinforced bakelite bushing; 10: Sliding resistor; 12: Gear mechanism; 13: Thermistor; 15: Screw; 17: Protective shell; 18: Pulse tube; 21: Ratchet; 301: Sliding contact; 302: First gear; 303: Secondary adjustment knob; 304: Second gear; 305: Third gear; 306: Tertiary adjustment knob; 307: Fourth gear; 308: Fifth gear; 309: Sixth gear; 310: Quadruple adjustment knob. Detailed Implementation

[0032] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0033] It should be noted that the structures, proportions, sizes, etc., illustrated in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding and reading. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0034] Example 1:

[0035] like Figure 1-4The gas absolute measurement sensor shown includes an inlet structure, an outlet structure, a measurement component, and a circuit component. The inlet structure is used for the gas to be detected to enter the sensor and contact the measurement component. The outlet structure is used for the gas to exit the sensor. The circuit component is electrically connected to the measurement component. The measurement component includes a thermistor 13, a compensation element 2, and an adjustment component. The thermistor 13 is placed in the measurement chamber 4 of the sensor, and the compensation element 2 is placed in the compensation chamber 3 of the sensor and its tightness is adjusted by the adjustment component.

[0036] The adjustment assembly includes a ratchet 21 and a drive component that drives the ratchet 21 to rotate. The ratchet 21 is connected to one end of the compensation element 2 for tightening or loosening the compensation element 2.

[0037] To ensure that the current-ampere performance of the thermistor is suitable for the sensor's measurement requirements, the heat dissipation of the compensation element is adjusted by adjusting the component. The drive in the adjustment component drives the ratchet to rotate, which tightens the compensation element connected to the ratchet, thereby compensating for the sensor measurement error caused by the relaxation of the thermistor in the measurement chamber due to long-term use.

[0038] In this embodiment, both the thermistor and the compensation element are made of spiral-shaped metal resistance wires.

[0039] In this embodiment, the upper and lower ends of the thermistor are fixed in the measuring chamber by elastic elements, allowing for sufficient heat exchange with the measured medium, such as air or nitrogen, which has high thermal conductivity.

[0040] In this embodiment, the compensation chamber is located below the measurement chamber and is connected to it.

[0041] In this embodiment, both the working chamber and the compensation chamber are enclosed by a shell 5, and a protective shell 17 is provided on the outside of the shell 5.

[0042] The sensor also includes an aviation plug 7, which is used to connect to external circuitry.

[0043] The gas in the compensation chamber is a heavy gas that has been purged of air impurities, while the gas entering the working chamber is a heavy gas containing air impurities. When the resistance wire in the measuring assembly is heated by the power supply, its thermal conductivity changes proportionally to the thermal conductivity of the gas mixture entering the working and compensation chambers. The gas sensor bridge circuit exhibits an imbalance, and the output voltage value, which is proportional to the air impurity content, also changes accordingly.

[0044] In this embodiment, the basic conversion error limit of the sensor is 0-20%·capacity%. -1Within the range, not exceeding 20% ​​of the upper limit of measurement. When the load resistance is 300±3Ω, the sensor's sensitivity to air content calculation is 6±1mV·capacity%. -1 .

[0045] The sensor of this invention is used to measure the absolute percentage content of light gases such as air and hydrogen fluoride in heavy industrial gases like uranium hexafluoride, and ammonia and hydrogen in carbon dioxide. It monitors the content of light impurity gases to ensure it is below specified values, thus meeting the requirements for safe production.

[0046] In this embodiment, the compensation element 2 is connected to the compensation chamber 3 via a connector. A resistance strain gauge for measuring the tension of the compensation element 2 is provided at the connection between the compensation element 2 and the connector. The resistance strain gauge is electrically connected to the controller, and the controller is electrically connected to the drive component.

[0047] In this embodiment, the driving component is a rotary drive motor.

[0048] The controller receives feedback from the strain gauge readings, which in turn controls a rotary drive motor to rotate and tighten the resistance wire of the compensation element, ensuring that the thermistor is adjusted to the optimal preload.

[0049] The following experiment investigated the effects of different tension forces on the resistance value and sensor accuracy error of the compensation element:

[0050] In the sensor measurement of the absolute percentage content of light impurities such as hydrofluoric acid and air in industrial uranium hexafluoride, experiments were conducted using resistance wires with different tensions in specific Examples 1-4 and Comparative Examples 1-3. The obtained resistance values ​​and sensor accuracy error results are shown in Table 1.

[0051] Table 1. Influence of resistance wires with different tensions on resistance value and sensor accuracy error.

[0052]

[0053] As can be seen from the examples and comparative examples, the optimal tension range is 0.4-0.7N. When the resistance wire tension is within this range, the resistance value and sensor accuracy error are less than 3%, meeting the requirements for high-precision sensor testing. When the resistance wire tension is 0.55N, the resistance value and sensor accuracy error are only 0.5%, enabling ultra-high precision sensor testing. When the resistance wire tension is outside this range, the resistance value and sensor accuracy error can reach more than 5%, making it difficult to meet the sensor testing requirements.

[0054] When measuring uranium hexafluoride, the sensor's thermistor and compensation element are made of 0.9 mm diameter metal wire, and have the same resistance at 0°C, which is 9.5 ± 0.5 Ω. The thermistor is placed in the analyte mixture and heated to 100°C by an electric current. The sensor's output resistance is no greater than 20 Ω.

[0055] In another embodiment, the driving member is located outside the compensation chamber 3, and the driving member is a screw 15 that passes through the ratchet to drive the ratchet to rotate.

[0056] In another embodiment, the adjustment assembly further includes a reversing limiter, one end of which passes through the ratchet and is connected to the compensation chamber 3 for fastening the ratchet.

[0057] Because the spiral wire forming the compensation element has low elasticity, it is equipped with a reverse limiter. After the adjustment is completed, the ratchet position is fixed by tightening the reverse limiter; this prevents the reverse adjustment of the compensation element or the reverse force caused by manual adjustment screws from affecting the resistance value of the resistance wire and thus affecting the accuracy of the sensor.

[0058] In this embodiment, the tension of the compensation element 2 is 0.4-0.7N.

[0059] In this embodiment, the circuit assembly includes a zero-position corrector, a sliding resistor 10, and a gear mechanism 12. The zero-position corrector is connected to the gear mechanism 12 via the sliding resistor 10. The movement of the sliding resistor 10 is used to adjust the resistance of the circuit section. The gear mechanism 12 is a multi-stage adjustment gear mechanism.

[0060] The resistance of the sensor circuit is adjusted by moving the sliding contact. The lower end of the sliding contact is connected to the first stage gear of the gear mechanism, which adjusts the resistance of the circuit in multiple stages.

[0061] In this embodiment, the gear mechanism includes a first gear 302, a secondary adjustment knob 303, a second gear 304, a third gear 305, a tertiary adjustment knob 306, a fourth gear 307, a fifth gear 308, a sixth gear 309, and a fourth adjustment knob 310. The first gear 302 and the second gear 304 mesh. The sliding resistor 10 is driven by the first gear 302 and the second gear 304. The third gear 305 is coaxially connected to the second gear 304 and meshes with the fourth gear 307. The secondary adjustment knob 303 and the tertiary adjustment knob 306 are driven by the third gear 305 and the fourth gear 307. The fourth gear 307 is coaxially connected to the fifth gear 308, and the fifth gear 308 is a helical gear. The sixth gear 309 is a meshing gear and meshes with the fifth gear 308. The fourth knob 310 is connected to the sixth gear 309.

[0062] This invention employs a multi-stage adjustment mechanism, overcoming the drawbacks of long adjustment times and low production efficiency associated with manual adjustments. Manual zero-point calibration can take over 10 minutes, while the multi-stage adjustment gear mechanism reduces this time to less than 1 minute. Addressing the common issue of inconvenience in adjusting on the circuit board, coarse adjustments are made directly on the zero-point calibrator, replacing precise adjustments via the circuit board. The number of adjustment stages can be appropriately increased or decreased according to accuracy requirements to ensure the sensor's measurement accuracy.

[0063] In this embodiment, the zero-position corrector material is beryllium bronze that has undergone special processes such as solution treatment and aging. It has the characteristics of high conductivity, high hardness, strong wear resistance, corrosion resistance and low coefficient of friction. This solves the problems of poor contact and unstable resistance caused by the low hardness, poor wear resistance and poor corrosion resistance of conductive materials.

[0064] In this embodiment, a zero-position corrector consisting of a balancing resistor for the output signal is fixed on the fabric-reinforced bakelite bushing 9.

[0065] In this embodiment, the sliding contact of the sliding resistor is connected to a multi-stage adjusting gear mechanism that can precisely adjust the sensor's input resistance. The four-stage adjusting gear mechanism designed in this invention can reduce the initial circuit potential to within ±2mV. The four-stage gear mechanism consists of two parts: the first part is the transmission mechanism between the sliding contact of the sliding resistor and the secondary adjusting knob. The first gear is a 100-tooth spur gear, and the second gear is a 20-tooth spur gear. The transmission ratio between the first gear and the second gear is 5:1. When the secondary adjusting knob rotates 5 times, the sliding contact of the sliding resistor slides 1 turn on the fabric-reinforced bakelite bushing. The second part is the transmission mechanism between the secondary and tertiary adjustment knobs. The second and third gears are coaxial. The third gear is a 40-tooth spur gear, and the fourth gear is a 20-tooth spur gear. The transmission ratio between the third and fourth gears is 2:1. When the tertiary adjustment knob is rotated 10 times, the sliding contact of the sliding resistor slides 1 turn on the fabric-reinforced bakelite bushing. The fourth and fifth gears are coaxial. The fifth gear is a 100-tooth helical gear, and the sixth gear is a 20-tooth helical gear. The transmission ratio between the fifth and sixth gears is 5:1. When the tertiary adjustment knob is rotated 50 times, the sliding contact of the sliding resistor slides 1 turn on the fabric-reinforced bakelite bushing.

[0066] A gear mechanism is used to adjust the resistance of the circuit section in multiple stages. First, the sliding contact of the sliding resistor is adjusted. When the display reading is within ±100mV, the second-stage adjustment knob is used; when the display reading is within ±20mV, the third-stage adjustment knob is used; and when the display reading is within ±10mV, the fourth-stage adjustment knob is used. By following these steps, the initial potential of the circuit can be reduced to within ±2mV.

[0067] The sensor measures a chamber pressure of 1.33 ± 0.13 kPa, and the sensor power supply must be disconnected when the pressure drops to 0.13 kPa. The upper and lower parts of the sensor housing are covered with aluminum shields to eliminate the influence of air convection on the sensor. The circuit insulation resistance of the sensor relative to the housing is not less than 20 MΩ, and the stabilization time of the sensor output voltage does not exceed 70 seconds.

[0068] In this embodiment, the sensor should be turned on for 24 hours, and after the analysis of the stable flow of the mixture, the output voltage should be adjusted to zero. The sliding contact of the sliding resistor of the output signal gradually changing corrector should be adjusted as accurately as possible to the middle of the working part. The screw of the compensation chamber should be rotated with a wrench to the zero value of the output voltage, and the output signal gradually changing variable resistor should be adjusted to set the output voltage to 3mV.

[0069] In this embodiment, the transmission ratio between the first gear 302 and the second gear 304 is 5:1, the transmission ratio between the third gear 305 and the fourth gear 307 is 2:1, and the transmission ratio between the fifth gear 308 and the sixth gear 309 is 5:1.

[0070] In this embodiment, both the air intake structure and the air outlet structure include a connector nozzle 8, a pulse tube 18, and a damping hollow ball 1. One end of the pulse tube 18 is connected to the connector nozzle 8, and the other end is connected to the measurement chamber 4 or compensation chamber 3 of the sensor. The damping hollow ball 1 is movable inside the pulse tube 18, and the damping hollow ball 1 is provided with circular intercepting holes that are evenly distributed and penetrate along three dimensions.

[0071] In this embodiment, the pulse tube in the air intake structure is connected to the measurement chamber through the central slot 6.

[0072] When gas flows in and out of the sensor, the airflow passes through the obstruction orifice and the gap between the small ball and the tapered tube, flowing from the outside into the working chamber. The obstruction is achieved by the gravity of the small ball itself, the variation in the gap between the inner diameter of the tapered tube and the outer diameter of the small ball, and the size of the obstruction orifice, adapting to the flow velocity of the gas being measured. This ensures that the airflow velocity along the thermistor element is not too high and remains uniform during gas exchange within the working chamber, controlling sufficient heat exchange between the airflow and the thermistor wire. For different test gases and different airflow velocities, by coordinating parameters such as the density, wall thickness, outer diameter, obstruction orifice diameter, number and distribution of obstruction orifices, and the taper of the pulse tube, a uniform and stable flow velocity of the incoming gas entering the working chamber is achieved. This makes signal acquisition more accurate and stable, reduces the impact of sudden changes in flow rate on the output signal, and improves the accuracy and precision of the sensor measurement.

[0073] In this embodiment, the central groove is placed inside the measuring chamber. The pulse tube terminal is a threaded connector with a connecting nut that connects to the working pipeline, and the gas to be measured is fed into the sensor along the pulse tube. The gas flows through the perforated flow-blocking ball, passes through the central groove, and enters the measuring chamber.

[0074] In this embodiment, the inlet and outlet of the pulse tube are tapered tubes with a certain taper. The large end of the tapered tube is in the direction of incoming flow. A damping hollow ball with a flow-cutting hole is installed inside the tapered tube. The outer diameter of the ball is smaller than the inner diameter of the large end of the tapered tube, and the outer diameter of the ball is larger than the inner diameter of the small end of the tapered tube. The ball can be put into the tapered tube by disassembling the connecting nut.

[0075] In this embodiment, when the sensor measures the absolute percentage content of light impurities such as hydrofluoric acid and air in industrial uranium hexafluoride, the taper of the conical tube ranges from 0 to 15 degrees. The damping hollow sphere is made of metallic nickel, and 18 circular flow-cutting holes are evenly distributed along three dimensions on the surface of the sphere. By setting damping hollow spheres with different flow-cutting hole diameters in the pulse tubes of the inlet and outlet structures respectively, the gas output signal is detected, as shown in Table 2.

[0076] Table 2. Influence of damping hollow spheres with different orifice diameters at the inlet and outlet on the output signal.

[0077]

[0078]

[0079] As shown in Table 2, by setting damping hollow spheres with appropriate orifice diameters at the inlet and outlet, the weak and difficult-to-detect signal generated by light gas can be improved into a stable and easily detectable hump signal, making the acquisition more accurate and stable, reducing the impact of signal acquisition accuracy and sudden flow changes on the output signal, and improving the accuracy and precision of sensor measurements. When the inlet orifice diameter is between 0.06-0.1 mm and the outlet orifice diameter is between 0.35-0.5 mm, the output signal is stable and easily detectable; when the inlet and outlet orifice diameters are smaller than these ranges, the output signal can be detected, but the signal output time is short and unstable; when the inlet and outlet orifice diameters are larger than these ranges, the output signal is unstable and difficult to detect.

[0080] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A gas absolute measurement sensor, comprising an inlet structure, an outlet structure, a measuring component, and a circuit component, wherein the inlet structure is used for the gas to be detected to enter the sensor and contact the measuring component, the outlet structure is used for the gas to exit the sensor, and the circuit component is electrically connected to the measuring component, characterized in that, The measuring assembly includes a thermistor (13), a compensation element (2), and an adjustment assembly. The thermistor (13) is placed in the measuring chamber (4) of the sensor, and the compensation element (2) is placed in the compensation chamber (3) of the sensor and its tightness is adjusted by the adjustment assembly. The adjustment assembly includes a ratchet (21) and a drive member for rotating the ratchet (21). The ratchet (21) is connected to one end of the compensation element (2) for tightening or loosening the compensation element (2).

2. The gas absolute measurement sensor according to claim 1, characterized in that, The compensation element (2) is connected to the compensation chamber (3) through a connector. A resistance strainer for measuring the tension of the compensation element (2) is provided at the connection between the compensation element (2) and the connector. The resistance strainer is electrically connected to the controller, and the controller is electrically connected to the drive.

3. A gas absolute measurement sensor according to claim 2, characterized in that, The driving component is a rotary drive motor.

4. A gas absolute measurement sensor according to claim 1, characterized in that, The driving component is located outside the compensation chamber (3). The driving component is a screw (15), which passes through the ratchet to drive the ratchet to rotate.

5. A gas absolute measurement sensor according to claim 4, characterized in that, The adjustment assembly also includes a reversing limiter, one end of which passes through the ratchet and is connected to the compensation chamber (3) for fastening the ratchet.

6. A gas absolute measurement sensor according to any one of claims 1-5, characterized in that, The tension of the compensation element (2) is 0.4-0.7N.

7. A gas absolute measurement sensor according to any one of claims 1-5, characterized in that, The circuit assembly includes a zero-position calibrator, a sliding resistor (10), and a gear mechanism (12). The zero-position calibrator is connected to the gear mechanism (12) via the sliding resistor (10). The movement of the sliding resistor (10) is used to adjust the resistance of the circuit section. The gear mechanism (12) is a multi-stage adjustment gear mechanism.

8. A gas absolute measurement sensor according to claim 7, characterized in that, The gear mechanism includes a first gear (302), a secondary adjustment knob (303), a second gear (304), a third gear (305), a tertiary adjustment knob (306), a fourth gear (307), a fifth gear (308), a sixth gear (309), and a fourth adjustment knob (310). The first gear (302) and the second gear (304) mesh. The sliding resistor (10) and the secondary adjustment knob (303) are connected by transmission through the first gear (302) and the second gear (304). The third gear (305)... The third gear (305) is coaxially connected to the second gear (304), and the fourth gear (307) meshes with the third gear (305). The second-stage adjustment knob (303) and the third-stage adjustment knob (306) are driven by the third gear (305) and the fourth gear (307). The fourth gear (307) is coaxially connected to the fifth gear (308), and the fifth gear (308) is a helical gear. The sixth gear (309) is a meshing gear and meshes with the fifth gear (308). The fourth-stage adjustment knob (310) is connected to the sixth gear (309).

9. A gas absolute measurement sensor according to claim 8, characterized in that, The transmission ratio between the first gear (302) and the second gear (304) is 5:1, the transmission ratio between the third gear (305) and the fourth gear (307) is 2:1, and the transmission ratio between the fifth gear (308) and the sixth gear (309) is 5:

1.

10. A gas absolute measurement sensor according to any one of claims 1-5, characterized in that, Both the air intake structure and the air outlet structure include a connector nozzle (8), a pulse tube (18), and a damping hollow ball (1). One end of the pulse tube (18) is connected to the connector nozzle (8), and the other end is connected to the measurement chamber (4) or compensation chamber (3) of the sensor. The damping hollow ball (1) is movable inside the pulse tube (18). The damping hollow ball (1) is provided with circular cut-off holes that are evenly distributed and penetrate along three dimensions.

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