A two-arm bridge type pressure detector

Abstract

The application discloses a double-arm electric bridge type pressure detector and belongs to the technical field of pressure detectors. The double-arm electric bridge type pressure detector comprises a detection shell and a sensing body shaft, a sealing ring is arranged between the detection shell and the sensing body shaft, and the detection shell and the sensing body are connected with the sealing ring through internal threads. In order to solve the problem that the algorithm is very dependent on the system optimization without support, the system needs to be debugged and corrected for many times in the actual use process, and the reaction speed is relatively slow in the detection process, the sensing cavity is used for sensing the temperature change in the external environment, and the temperature change is transmitted to the internal temperature sensing module in the mode of medium heat exchange principle, so that the temperature sensing module can further sense the environmental temperature condition, and compensation calculation is carried out according to the temperature change, so as to guarantee the detection precision of the detector in different environments.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of pressure detector, in particular to a double-arm bridge type pressure detector. BACKGROUND

[0002] The piezoresistive pressure sensor is also called diffusion silicon pressure sensor, which is a sensor made of piezoresistive effect of single crystal silicon material and integrated circuit technology. The resistivity of single crystal silicon material changes after being subjected to force, and the output of the electric signal proportional to the force change can be obtained through the measurement circuit. The piezoresistive sensor is used for measuring and controlling pressure, tension, pressure difference and other physical quantities which can be converted into force change.

[0003] The Chinese patent with publication number CN210071188U discloses a double-arm bridge type pressure detector, which is modularly designed, has a smooth outer surface, can be directly attached to any plane for use, and can be directly connected to a single-chip microcomputer to obtain accurate pressure measurement values after filtering and analog-digital conversion, greatly facilitating the use.

[0004] In the above patent, the sensing accuracy of the pressure detector is improved through modular design, but such a non-supported system optimization is very dependent on the algorithm, and needs to be debugged and corrected many times in the actual use process, and the reaction speed is relatively slow in the detection process. Therefore, it does not meet the existing demand, and a double-arm bridge type pressure detector is proposed. SUMMARY

[0005] The present application aims to provide a double-arm bridge type pressure detector, which is used to sense the temperature change in the external environment, and transmits the temperature change to the internal temperature sensing module through the medium heat exchange principle. In this way, the temperature sensing module can further sense the environmental temperature, and compensate according to the temperature change to ensure the detection accuracy of the detector in different environments, which can solve the problems in the prior art.

[0006] In order to achieve the above object, the present application provides the following technical scheme: a double-arm bridge type pressure detector, comprising a detection shell and a sensing body shaft, a sealing ring is arranged between the detection shell and the sensing body shaft, the detection shell and the sensing body are connected with the sealing ring through internal threads, a detection air hole is arranged at the top of the detection shell, a sealed partition cavity is arranged in the detection shell, the detection air hole extends to the inside of the sealed partition cavity, a silica gel diaphragm is arranged at the bottom of the sealed partition cavity, the silica gel diaphragm is connected with the detection shell through a clamping groove, an interface end shaft is arranged at the bottom of the sensing body shaft, the interface end shaft and the sensing body shaft are arranged in an integrated structure, an interface needle is arranged in the interface end shaft, a low-pressure cavity is arranged in the sensing body shaft, a sensing cavity is arranged below the low-pressure cavity, a partition plate is arranged between the sensing cavity and the low-pressure cavity, and the silica gel diaphragm is located between the sealed partition cavity and the low-pressure cavity.

[0007] Preferably, a support silica ring is arranged in the low-pressure cavity, the support silica ring is connected with the sensing body shaft through a screw, a single-crystal silicon diaphragm is arranged above the support silica ring, a constant-pressure cavity is arranged between the support silica ring and the single-crystal silicon diaphragm, and a signal processing module is arranged in the sensing cavity.

[0008] Preferably, end Nu resistors are arranged on the outer surface of the single-crystal silicon diaphragm, the end Nu resistors are four in number, the end Nu resistors are connected with the single-crystal silicon diaphragm in a pasting mode, the end Nu resistors are electrically connected with each other, and bridge arm resistors are arranged on the outer side of the end Nu resistors and electrically connected with the end Nu resistors.

[0009] Preferably, the bridge arm resistors are connected with the signal processing module through a sleeve rubber lead, the signal processing module is electrically connected with the interface needle, the wall thickness of the sensing cavity is smaller than that of the low-pressure cavity, and a temperature sensing expansion module is arranged between the support silica ring and the signal processing module.

[0010] Preferably, the temperature sensing expansion module is arranged in the sensing cavity, and the temperature sensing expansion module comprises a silver pipe shaft, the silver pipe shaft is connected with the sensing body shaft through a screw, a magnetic sensing displacement sleeve shaft is arranged on the inner side of the silver pipe shaft, and the magnetic sensing displacement sleeve shaft is electrically connected with the signal processing module.

[0011] Preferably, a counterweight piston is arranged in the magnetic sensing displacement sleeve shaft and connected with the magnetic sensing displacement sleeve shaft in a pasting mode, a compressed gas cavity is arranged in the silver pipe shaft, and the counterweight piston extends to the inside of the compressed gas cavity.

[0012] Preferably, an extension sensing end is arranged above the compressed gas cavity and arranged in an integrated structure with the silver pipe shaft, and the extension sensing end extends to the inside of the low-pressure cavity.

[0013] Preferably, the temperature sensing expansion module is responsible for transmitting the expansion distance between the counterweight piston and the magnetic sensing displacement sleeve shaft to the coefficient conversion unit and the temperature difference compensation module inside the signal processing module;

[0014] The coefficient conversion unit associates the expansion distance of the piston with the expansion coefficient of the gas, and then converts the expansion coefficient to the ambient temperature; wherein,

[0015] Converting the ambient temperature includes:

[0016] Step 1: According to the expansion coefficient, a linear function of the difference between the induction pressure in the induction cavity and the ambient pressure is constructed:

[0017]

[0018] Wherein, Y(t) represents a linear function of the difference between the induction pressure in the induction cavity (204) and the ambient pressure; p n，t represents the induction pressure in the induction cavity (204) at time t; p h，t represents the induction pressure of the ambient pressure at time t; z t represents the expansion coefficient at time t; b represents the pressure constant; M represents the induction time;

[0019] Step 2: Through the difference linear function, regression prediction conversion is carried out to determine the ambient temperature:

[0020]

[0021] Wherein, γ represents the kernel function; W represents the ambient temperature; β t represents the regression prediction coefficient at time t;

[0022] The temperature difference compensation module: after obtaining the converted temperature data, the temperature value is calculated, the influence range of the ambient temperature on the detection value is simulated, and the final detection value is compensated.

[0023] Preferably, the temperature difference compensation module transmits the compensation signal to the nonlinear correction unit, wherein the input end of the nonlinear correction unit is connected with the resistance induction module;

[0024] The nonlinear correction unit: the data signal detected by the sensor is corrected horizontally through the feedback temperature compensation;

[0025] Wherein, the horizontal correction includes the following steps:

[0026] Step 1: Obtain the data signal detected by the sensor at each time temperature compensation, and generate a time compensation sequence H:

[0027] H = [T0, T1, T2……T t ]

[0028] Wherein, T0 represents the temperature compensation of initial time; T t represents the temperature compensation of t time;

[0029] Step 2: by time compensation sequence, temperature compensation is taken as the horizontal coordinate, and the horizontal compensation internal mode control function is formed:

[0030]

[0031] Wherein, P(k, F t ) represents the temperature compensation feedback of t time to the expected data signal detected by the sensor and the expected state function under the ideal temperature k; L(epsilon, k) represents the closed loop transfer function under the ideal temperature k and the nonlinear correction coefficient epsilon; P(k, T t ) represents the real-time data signal detected by the sensor and the real-time state function under the ideal temperature k; y(t) is the horizontal compensation internal mode control function;

[0032] Step 3: according to the horizontal compensation internal mode function, the corresponding resistance signal is determined in the preset resistance adjustment table, and is sent to the resistance induction module;

[0033] The resistance induction module is responsible for collecting sensor detection information.

[0034] Preferably, the output signal of the nonlinear correction unit is transmitted to the signal feedback unit through a current conversion unit and an output amplifier, wherein the current conversion unit is responsible for converting the electrical signal into a data signal, and the data signal is amplified through the amplifier and then enters the signal feedback unit for analysis and feedback.

[0035] Compared with the prior art, the beneficial effects of the present application are:

[0036] 1、The detector of the present application is composed of three main areas, which are sealed partition cavity, low pressure cavity and induction cavity, wherein the sealed partition cavity is located in the inside of the detection shell, when the gas pressure is generated, the gas flow enters the sealed partition cavity from the detection gas hole, when the pressure in the sealed partition cavity changes, the silica gel diaphragm connected with the low pressure cavity at the bottom will be deformed, thereby directly affecting the gas pressure in the low pressure cavity, and the air humidity in the external environment can be effectively prevented from affecting the detector through the indirect transmission mode, the induction cavity is located below the low pressure cavity, the induction cavity is used for sensing the temperature change in the external environment, and the temperature change is transmitted to the internal temperature sensing module through the medium heat exchange principle, so that the environmental temperature condition can be further sensed through the temperature sensing module, and compensation calculation is carried out according to the temperature change, so as to guarantee the detection precision of the detector in different environments.

[0037] 2、The compressed gas cavity in the silver pipe shaft is filled with compressed gas, the molecular structure of the compressed gas is more compact, when the temperature in the external environment is transmitted to the inside of the induction cavity, the silver pipe shaft with superior heat conduction and cold conduction properties can rapidly exchange heat with the temperature change in the inside of the induction cavity, when the temperature of the silver pipe shaft changes, the gas molecular structure in the inside of the silver pipe shaft also changes, when the temperature is higher, the gas in the inside expands, the expanded gas pushes the counterweight piston outward, on the contrary, when the temperature is lower, the gas shrinks, at this time, the counterweight piston moves inward, the change value generated by the movement is uploaded to the temperature sensing expansion module, then the calculation module associates the extension distance of the piston with the expansion coefficient of the gas, the environmental temperature is converted from the expansion coefficient, after the converted temperature data is acquired, the temperature value is calculated, the influence range of the environmental temperature on the detection value is simulated, and the final detection value is compensated. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 It is the overall front view of the application;

[0039] Figure 2 It is the overall side view of the application;

[0040] Figure 3 It is the overall internal structure schematic diagram of the application;

[0041] Figure 4 It is the support silicon ring structure schematic diagram of the application;

[0042] Figure 5 It is Figure 3 the enlarged structure schematic diagram of A;

[0043] Figure 6 It is the temperature compensation composition structure diagram of the application.

[0044] In the figure: 1, detection shell; 2, sensing body shaft; 3, sealing ring; 4, temperature sensing expansion module; 5, coefficient conversion unit; 6, temperature difference compensation module; 7, resistance induction module; 8, non-linear correction unit; 9, current conversion unit; 10, output amplifier; 11, signal feedback unit; 101, detection air hole; 102, sealing partition cavity; 103, silica gel diaphragm; 201, interface end shaft; 202, interface needle; 203, low pressure cavity; 204, induction cavity; 205, signal processing module; 206, support silicon ring; 207, single crystal silicon diaphragm; 208, end resistance; 2081, bridge arm resistance; 2082, sleeve glue lead; 401, compressed gas cavity; 402, extension induction end; 403, counterweight piston; 404, silver pipe shaft; 405, magnetic induction displacement sleeve shaft. DETAILED DESCRIPTION

[0045] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by a person of ordinary skill in the art without creative effort belong to the scope of protection of the present application.

[0046] Please refer to Figures 1-3 The present application provides an embodiment: a double-arm bridge type pressure detector, comprising a detection shell 1 and a sensor shaft 2, a sealing ring 3 is arranged between the detection shell 1 and the sensor shaft 2, the detection shell 1 and the sensor shaft are connected with the sealing ring 3 through internal threads, a detection gas hole 101 is arranged at the top of the detection shell 1, a sealed partition cavity 102 is arranged in the detection shell 1, the detection gas hole 101 extends to the inside of the sealed partition cavity 102, a silica gel diaphragm 103 is arranged at the bottom of the sealed partition cavity 102, the silica gel diaphragm 103 is connected with the detection shell 1 through a clamping groove, an interface end shaft 201 is arranged at the bottom of the sensor shaft 2, the interface end shaft 201 is arranged in an integral structure with the sensor shaft 2, an interface needle 202 is arranged in the interface end shaft 201, a low-pressure cavity 203 is arranged in the sensor shaft 2, a sensing cavity 204 is arranged below the low-pressure cavity 203, a partition plate is arranged between the sensing cavity 204 and the low-pressure cavity 203, and the silica gel diaphragm 103 is located between the sealed partition cavity 102 and the low-pressure cavity 203.

[0047] The inside of the detector is composed of three main areas, which are the sealed partition cavity 102, the low-pressure cavity 203 and the sensing cavity 204. The sealed partition cavity 102 is located in the inside of the detection shell 1. When the gas pressure is generated, the airflow enters the sealed partition cavity 102 from the detection gas hole 101. When the pressure in the sealed partition cavity 102 changes, the silica gel diaphragm 103 at the bottom connected with the low-pressure cavity 203 will be deformed, thereby directly affecting the gas pressure in the low-pressure cavity 203. Through this indirect transmission mode, the influence of the air humidity in the external environment on the detector can be effectively prevented.

[0048] The sensing cavity 204 is located below the low-pressure cavity 203. The sensing cavity 204 is used to sense the temperature change in the external environment, and transmits the temperature change to the internal temperature sensing module through the medium heat exchange principle. In this way, the environmental temperature condition can be further sensed by the temperature sensing module, and compensation calculation can be performed according to the temperature change, so as to guarantee the detection accuracy of the detector in different environments.

[0049] Please refer to Figures 3-4The inside of the low-pressure cavity 203 is provided with a support silicon ring 206, the support silicon ring 206 is connected with the sensing body shaft 2 through a screw, the upper side of the support silicon ring 206 is provided with a single crystal silicon diaphragm 207, a constant-pressure cavity is arranged between the support silicon ring 206 and the single crystal silicon diaphragm 207, the inside of the inductive cavity 204 is provided with a signal processing module 205, the outer surface of the single crystal silicon diaphragm 207 is provided with terminal resistance 208, the terminal resistance 208 is four, the terminal resistance 208 is connected with the single crystal silicon diaphragm 207, the terminal resistance 208 is electrically connected, the outer side of the terminal resistance 208 is provided with a bridge arm resistance 2081, the bridge arm resistance 2081 is electrically connected with the terminal resistance 208, the outer surface of the single crystal silicon diaphragm 207 is provided with terminal resistance 208, the terminal resistance 208 is four, the terminal resistance 208 is connected with the single crystal silicon diaphragm 207, the terminal resistance 208 is electrically connected, the outer side of the terminal resistance 208 is provided with a bridge arm resistance 2081, the bridge arm resistance 2081 is electrically connected with the terminal resistance 208, the bridge arm resistance 2081 is connected with the signal processing module 205 through a sleeve glue lead 2082, the signal processing module 205 is electrically connected with the interface needle 202, the wall thickness of the inductive cavity 204 is less than the wall thickness of the low-pressure cavity 203, a temperature sensing expansion module 4 is arranged between the support silicon ring 206 and the signal processing module 205;

[0050] When the pressure generated by the deformation of the silica gel diaphragm 103 acts on the inside of the low-pressure cavity 203, the single crystal silicon diaphragm 207 above the support silicon ring 206 will also change, and the deformation arc of the single crystal silicon diaphragm 207 is proportional to the deformation arc of the silica gel diaphragm 103, and the crystal lattice is deformed, so that the carriers are scattered from one energy valley to another, causing the mobility of the carriers to change, the average amount of longitudinal and transverse carriers is disturbed, so that the resistivity of silicon changes, at this time, the resistance value of the terminal resistance 208 on the surface of the diaphragm will change, wherein the terminal resistance 208 shifts the relative position of the additional resistance, so that the additional resistance is no longer in series with the low resistance, and the additional resistance is transferred to the power supply circuit, eliminating the influence of the additional resistance on the measurement accuracy;

[0051] The wall thickness of the inductive cavity 204 is less than the wall thickness of the low-pressure cavity 203, so that the space temperature change in the inductive cavity 204 area is more sensitive than that in the low-pressure cavity 203.

[0052] Please refer to Figure 3 and Figure 5, the temperature sensing expansion module 4 is arranged in the inside of the induction cavity 204, the temperature sensing expansion module 4 includes a silver pipe shaft 404, the silver pipe shaft 404 is connected with the sensing body shaft 2 through screw, the inside of the silver pipe shaft 404 is provided with a magnetic induction displacement sleeve shaft 405, the magnetic induction displacement sleeve shaft 405 is electrically connected with the signal processing module 205, the inside of the magnetic induction displacement sleeve shaft 405 is provided with a counterweight piston 403, the counterweight piston 403 is connected with the magnetic induction displacement sleeve shaft 405, the inside of the silver pipe shaft 404 is provided with a compressed gas cavity 401, the counterweight piston 403 extends to the inside of the compressed gas cavity 401, the top of the compressed gas cavity 401 is provided with an extension induction end 402, the extension induction end 402 is arranged as an integral structure with the silver pipe shaft 404, the extension induction end 402 extends to the inside of the low-pressure cavity 203;

[0053] The compressed gas cavity 401 in the silver pipe shaft 404 is filled with compressed gas, the molecular structure of the compressed gas is more compact, when the temperature in the external environment is transmitted to the inside of the induction cavity 204, the silver pipe shaft 404 with superior heat conduction and cold conduction properties can rapidly exchange heat with the temperature change in the inside of the induction cavity 204, when the temperature of the silver pipe shaft 404 changes, the gas molecular structure in the inside of the silver pipe shaft 404 will also change, when the temperature is higher, the gas in the inside will expand, the expanded gas will push the counterweight piston 403 outward, on the contrary, when the temperature is lower, the gas will shrink, at this time, the counterweight piston 403 will move inward, the change value generated by the movement is uploaded to the temperature sensing expansion module 4, then the piston extension and contraction distance and the expansion coefficient of the gas are associated by the calculation module, the ambient temperature is converted by the expansion coefficient, after the converted temperature data is obtained, the temperature value is calculated, the influence range of the ambient temperature on the detection value is simulated, and the final detection value is compensated.

[0054] Please refer to Figure 6 The temperature sensing expansion module 4 is responsible for uploading the extension and contraction distance between the counterweight piston 403 and the magnetic induction displacement sleeve shaft 405 to the coefficient conversion unit 5 and the temperature difference compensation module 6 in the inside of the signal processing module 205.

[0055] The coefficient conversion unit 5: the extension and contraction distance of the piston is associated with the expansion coefficient of the gas, and the ambient temperature is converted by the expansion coefficient; wherein,

[0056] The ambient temperature converted includes:

[0057] Step 1: according to the expansion coefficient, a difference linear function of the induction pressure in the induction cavity 204 and the ambient pressure is constructed:

[0058]

[0059] Wherein, Y(t) represents the difference linear function of the induction pressure in the induction cavity (204) and the ambient pressure; pn，t P(t) represents the induction pressure in the induction cavity 204 at time t; p h，t P(t) represents the induction pressure in the induction cavity 204 at time t; p t P(t) represents the induction pressure in the induction cavity 204 at time t; p

[0060] Because there is a pressure difference between the pressure in the induction cavity and the ambient pressure when determining the ambient temperature, there is also a temperature difference when converting the temperature, and the temperature difference and the pressure difference are associated with each other, so the interpolation coefficient is the same. Therefore, the present application constructs a linear function in a period of time to calculate the linear function of the pressure difference in a period of time. The temperature is converted in proportion by the linear function of the pressure difference. In the interpolation linear function of the pressure difference, the present application subtracts the induction pressure of the ambient pressure from the induction pressure in the induction cavity 204 at each time, which is the internal and external pressure difference, and b is a constant to prevent the overall calculation from being biased when the internal and external pressure difference is 0 at the initial time. By the above formula, a linear pressure difference function is constructed.

[0061] Step 2: Convert the ambient temperature by the difference linear function and regression prediction:

[0062]

[0063] Where γ represents the kernel function; W represents the ambient temperature; β t P(t) represents the induction pressure in the induction cavity 204 at time t; p

[0064] After the linear pressure difference function is calculated, the ambient temperature needs to be converted, and the present application uses SGN, a step function, to convert to a specific value for easy processing of electrical signals. Y(t) is brought into the specific expansion coefficient conversion process as a difference function, and -γ is a kernel function. The reason for using a negative value is that if the exp function calculation is positive, it is too large, and if it is negative, it is less than 1, and the calculation result is converted to a temperature value more quickly. If a positive value is used, it needs to be operated again in proportion to reduce the constant, and the constant also needs to be converted. Through the above conversion method, the accuracy of the ambient temperature detection result can be improved, and the conversion rule of the ambient temperature and the induction temperature in the induction cavity can be determined, thereby facilitating the induction correction of the overall pressure detector.

[0065] The temperature difference compensation module 6 calculates the temperature value after obtaining the conversion temperature data, simulates the influence range of the ambient temperature on the detection value, and compensates the final detection value.

[0066] The temperature difference compensation module 6 transmits the compensation signal to the nonlinear correction unit 8, wherein the input end of the nonlinear correction unit 8 is connected with the resistance induction module 7;

[0067] The nonlinear correction unit 8: the data signal detected by the sensor is corrected transversely by the feedback temperature compensation; wherein,

[0068] The transverse correction includes the following steps:

[0069] Step 1: Obtain the data signal detected by the sensor at each time temperature compensation, and generate a time compensation sequence H:

[0070] H = [T0, T1, T2……T t ]

[0071] Wherein, T0 represents the temperature compensation at the initial time; T t represents the temperature compensation at t time;

[0072] When the transverse correction is performed, the coordinates of the transverse compensation are first determined, and the data signal detected by the sensor at each time temperature compensation is used as the transverse coordinate, so the corresponding time compensation sequence is set.

[0073] Step 2: Through the time compensation sequence, the temperature compensation is taken as the transverse coordinate, and the inner mode control function of the transverse compensation is constructed:

[0074]

[0075] Wherein, P(k, F t ) represents the expected data signal detected by the sensor at t time feedback temperature compensation and the expected state function at ideal temperature k; L(ε, k) represents the closed-loop transfer function at ideal temperature k and nonlinear correction coefficient ε; P(k, T t ) represents the real-time data signal detected by the sensor at t time feedback temperature compensation and the real-time state function at ideal temperature k; y(t) is the inner mode control function of the transverse compensation;

[0076] In the calculation process of the transverse compensation, the state model of the inner mode control is constructed according to 0 time, that is, the initial time to t time, and the expected value and the actual detection value are compared by the expected state function under the correction of the closed-loop transfer function, so as to determine the transverse compensation value obtained by the deviation.

[0077] Step 3: According to the inner mode function of the transverse compensation, the corresponding resistance signal is determined in the preset resistance adjustment table, and is sent to the resistance sensing module 7;

[0078] In step 3, the resistance adjustment value of the resistance sensing module is determined by the transverse compensation value in the pre-set resistance adjustment table, and the temperature compensation is realized.

[0079] The resistance sensing module 7: responsible for collecting sensor detection information.

[0080] The output signal of the nonlinear correction unit 8 is transmitted to the signal feedback unit 11 after passing through the current conversion unit 9 and the output amplifier 10, wherein the current conversion unit 9 is responsible for converting the electrical signal into a data signal, which is amplified by the amplifier and then enters the signal feedback unit 11 for analysis and feedback.

[0081] The working principle is that the airflow enters the sealed partition cavity 102 from the detection air hole 101, when the pressure inside the sealed partition cavity 102 changes, the silica gel diaphragm 103 connected to the low-pressure cavity 203 at the bottom will deform, thereby directly affecting the gas pressure inside the low-pressure cavity 203, when the pressure generated by the deformation of the silica gel diaphragm 103 acts on the inside of the low-pressure cavity 203, the single crystal silicon diaphragm 207 above the support silicon ring 206 will also change, and the deformation arc of the single crystal silicon diaphragm 207 is proportional to that of the silica gel diaphragm 103, the crystal lattice is deformed, the carriers are scattered from one energy valley to another, the mobility of the carriers changes, the average amount of longitudinal and transverse carriers is disturbed, and thus the resistivity of silicon changes, at this time the end resistance 208 on the surface of the diaphragm will change, wherein the end resistance 208 shifts the relative position of the additional resistance, so that the additional resistance is no longer in series with the low resistance, and the additional resistance is transferred to the power supply circuit, eliminating the influence of the additional resistance on the measurement accuracy, and the indirect transmission can effectively prevent the influence of air humidity in the external environment on the detector, the sensing cavity 204 is located below the low-pressure cavity 203, and the sensing cavity 204 is used to sense the temperature change in the external environment and transmit the temperature change to the internal silver pipe shaft 404 through the medium heat exchange principle, the compression gas cavity 401 in the silver pipe shaft 404 is filled with compressed gas, and the molecular structure of the compressed gas is more compact, when the temperature in the external environment is transmitted to the inside of the sensing cavity 204, the silver pipe shaft 404 itself has superior heat conduction and cooling properties, which can quickly exchange heat with the temperature change in the sensing cavity 204, when the temperature of the silver pipe shaft 404 changes, the gas molecular structure inside the silver pipe shaft 404 will also change, when the temperature is higher, the gas inside will expand, and the expanded gas will push the counterweight piston 403 outward, on the contrary, when the temperature is lower, the gas will shrink, at this time the counterweight piston 403 will move inward, and the change value generated by the movement will be uploaded to the temperature sensing expansion module 4, then the piston extension distance and the expansion coefficient of the gas are associated by the calculation module, the ambient temperature is calculated from the expansion coefficient, and after obtaining the calculated temperature data, the temperature value is calculated, the influence range of the environment temperature on the detection value is simulated, and the final detection value is compensated, so that the temperature sensing module can further sense the environment temperature, and the compensation calculation is made according to the temperature change, so as to ensure the detection accuracy of the detector in different environments.

[0082] It has to be noted that, in the present document, the terms "first", "second", etc. merely serve to identify different entities or actions from each other, without necessarily requiring or implying any actual relationship or order between these entities or actions. Moreover, the terms "comprises", "comprising", or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0083] While embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, combinations, and variations of the embodiments can be undertaken without departing from the spirit and scope of the present application, which is defined by the appended claims and their equivalents.

Claims

1. A dual arm bridge type pressure detector comprising a detection housing (1) and a sensor body shaft (2), characterized in that: The detection shell (1) and the sensing body shaft (2) are provided with a sealing ring (3), the detection shell (1) and the sensing body are connected with the sealing ring (3) through internal threads, the top of the detection shell (1) is provided with a detection air hole (101), the inside of the detection shell (1) is provided with a sealed partition cavity (102), the detection air hole (101) extends to the inside of the sealed partition cavity (102), the bottom of the sealed partition cavity (102) is provided with a silica gel diaphragm (103), the silica gel diaphragm (103) is connected with the detection shell (1) through a clamping groove, the bottom of the sensing body shaft (2) is provided with an interface end shaft (201), the interface end shaft (201) and the sensing body shaft (2) are provided as an integral structure, the inside of the interface end shaft (201) is provided with an interface needle (202), the inside of the sensing body shaft (2) is provided with a low-pressure cavity (203), the lower part of the low-pressure cavity (203) is provided with a sensing cavity (204), a partition plate is arranged between the sensing cavity (204) and the low-pressure cavity (203), and the silica gel diaphragm (103) is located between the sealed partition cavity (102) and the low-pressure cavity (203); The inside of the low-pressure cavity (203) is provided with a support silicon ring (206), the support silicon ring (206) is connected with the sensing body shaft (2) through screws, the upper part of the support silicon ring (206) is provided with a single crystal silicon diaphragm (207), a constant pressure cavity is arranged between the support silicon ring (206) and the single crystal silicon diaphragm (207), and the inside of the sensing cavity (204) is provided with a signal processing module (205); The outer surface of the single crystal silicon diaphragm (207) is provided with four end-nu resistors (208), the end-nu resistors (208) are connected with the single crystal silicon diaphragm (207), the end-nu resistors (208) are electrically connected, and the outer side of the end-nu resistor (208) is provided with a bridge arm resistor (2081), the bridge arm resistor (2081) is electrically connected with the end-nu resistor (208); The bridge arm resistor (2081) is connected with the signal processing module (205) through a sleeve glue lead (2082), the signal processing module (205) is electrically connected with the interface needle (202), the wall thickness of the sensing cavity (204) is smaller than that of the low-pressure cavity (203), and a temperature sensing expansion module (4) is arranged between the support silicon ring (206) and the signal processing module (205).

2. A dual arm bridge pressure detector according to claim 1, wherein: The temperature sensing expansion module (4) is arranged in the sensing cavity (204), and the temperature sensing expansion module (4) comprises a silver pipe shaft (404), the silver pipe shaft (404) is connected with the sensing body shaft (2) through screws, the inner side of the silver pipe shaft (404) is provided with a magnetic sensing displacement sleeve shaft (405), and the magnetic sensing displacement sleeve shaft (405) is electrically connected with the signal processing module (205).

3. A dual arm bridge pressure detector according to claim 2, wherein: The interior of the magnetic induction displacement sleeve shaft (405) is provided with a counterweight piston (403) which is connected with the magnetic induction displacement sleeve shaft (405) in close contact, and the interior of the silver pipe shaft (404) is provided with a compressed gas cavity (401), and the counterweight piston (403) extends to the interior of the compressed gas cavity (401).

4. A dual arm bridge pressure detector according to claim 3, wherein: The upper portion of the compressed gas cavity (401) is provided with an extension induction end (402) which is arranged in an integral structure with the silver pipe shaft (404), and the extension induction end (402) extends to the interior of the low-pressure cavity (203).

5. A dual arm bridge pressure detector according to claim 4, wherein: The temperature sensing expansion module (4) is responsible for transmitting the expansion distance between the counterweight piston (403) and the magnetic induction displacement sleeve shaft (405) to the coefficient conversion unit (5) and the temperature difference compensation module (6) in the signal processing module (205); The coefficient conversion unit (5) is used for associating the expansion distance of the piston with the expansion coefficient of the gas, and then converting the ambient temperature from the expansion coefficient; wherein, The conversion of the ambient temperature comprises: Step 1: According to the expansion coefficient, a difference linear function of the induction pressure in the induction cavity (204) and the ambient pressure is constructed: ； wherein, represents a linear function of the difference between the inductive pressure and the ambient pressure in the induction cavity (204); represents the inductive pressure in the induction cavity (204) at a time instant; represents the inductive pressure at the ambient pressure at a time instant; represents the expansion coefficient at a time instant; represents the pressure constant; represents the induction time; Step 2: The difference linear function is used for regression prediction conversion to determine the ambient temperature: ； wherein, represents a kernel function; represents an ambient temperature; represents a regression prediction coefficient at the time instant The temperature difference compensation module (6) is used for calculating the temperature value after obtaining the converted temperature data, simulating the influence range of the ambient temperature on the detection value, and compensating the final detection value.

6. A dual arm bridge pressure detector according to claim 5, wherein: The temperature difference compensation module (6) transmits the compensation signal to the nonlinear correction unit (8), wherein the input end of the nonlinear correction unit (8) is connected with the resistance induction module (7); The nonlinear correction unit (8) is used for performing horizontal correction on the data signal detected by the sensor through the feedback temperature compensation; wherein, The horizontal correction comprises the following steps: Step 1 : Obtain the data signal detected by the temperature-compensated pair of sensors at each time instant and generate a time-compensated sequence : ； wherein represents the temperature compensation at the initial time point; represents the temperature compensation at the time point Step 2: The temperature compensation is taken as a horizontal coordinate to form an internal mode control function of horizontal compensation through a time compensation sequence: ； in, express Real-time temperature compensation ensures that the sensor detects the desired data signal and the ideal temperature. The expected state function under the following conditions; Indicates ideal temperature and nonlinear correction coefficients The closed-loop transfer function is as follows; express Real-time temperature compensation based on the sensor's detected real-time data signal and ideal temperature. Real-time state function; The internal model control function for lateral compensation; Step 3: According to the internal mode function of horizontal compensation, the corresponding resistance signal is determined in the preset resistance adjustment table and is sent to the resistance induction module (7); The resistance induction module (7) is responsible for collecting the sensor detection information.

7. A dual arm bridge pressure detector according to claim 6, wherein: The output signal of the nonlinear correction unit (8) is transmitted to the signal feedback unit (11) through the current conversion unit (9) and the output amplifier (10), wherein the current conversion unit (9) is responsible for converting the electrical signal into a data signal, and the data signal is amplified by the amplifier and then enters the signal feedback unit (11) for analysis and feedback.

Images