Constant-temperature capacitive pressure sensing device

Abstract

The invention discloses a constant-temperature capacitive pressure sensing device, and relates to the technical field of sensors. The device comprises a sensing assembly, the sensing assembly comprises a shell, a first electrode and a second electrode, and the first electrode and the second electrode are arranged in the shell; the first heating film is arranged on the inner wall of the shell; the second heating film is arranged on the surface of the second electrode; and the control assembly is connected with the first heating film and the second heating film, and the control assembly is used for measuring the temperature in the shell and controlling the voltage of the first heating film and the voltage of the second heating film according to the preset temperature. The first heating film and the second heating film are arranged on the inner wall of the shell and the surface of the second electrode respectively, and the internal temperature of the shell is accurately regulated and controlled in combination with the control assembly, so that the influence of environment temperature fluctuation on the detection precision of the capacitive pressure sensor is effectively reduced.

Description

Technical Field

[0001] The present application relates to the field of sensor technology, and in particular to a constant temperature capacitive pressure sensor device. Background Art

[0002] Capacitive pressure sensor is a kind of pressure sensor that uses capacitive sensitive elements to convert the measured pressure into an electrical output that is in a certain relationship with it. Its working principle is based on the capacitive effect, that is, when the measured object is compressed, it will produce a small deformation, thereby changing the capacitance to measure the pressure.

[0003] A single capacitive pressure sensor generally consists of an electrode and an elastic conductive film. When the elastic conductive film is deformed by pressure, the capacitance formed between the film and the fixed electrode changes. This change in capacitance is converted into an electrical signal output that has a certain relationship with the voltage through the measurement circuit, thereby realizing the measurement of pressure. However, the capacitance signal is an extremely sensitive signal. In the process of using a capacitive pressure sensor for detection, it is easily affected by the ambient temperature, resulting in poor detection accuracy, unstable zero point, and detection results that change with temperature. Summary of the invention

[0004] In view of this, the present application provides a constant temperature capacitive pressure sensing device, the main purpose of which is to solve the technical problems that in the process of using a capacitive pressure sensor for detection, it is easily affected by the ambient temperature, resulting in poor detection accuracy, unstable zero point, and detection results changing with temperature.

[0005] The present application provides a constant temperature capacitive pressure sensing device, comprising:

[0006] A sensor assembly, the sensor assembly comprising a housing, a first electrode and a second electrode, wherein the first electrode and the second electrode are arranged in the housing;

[0007] a first heating film, wherein the first heating film is arranged on the inner wall of the housing;

[0008] a second heating film, wherein the second heating film is arranged on a surface of the second electrode;

[0009] A control component is connected to the first heating film and the second heating film, and is used to measure the temperature inside the housing and control the voltage of the first heating film and the second heating film according to a preset temperature.

[0010] In a feasible implementation manner, the first heating film includes:

[0011] a first base film, wherein the first base film is a flexible base film, and an area of ​​the first base film is smaller than or equal to an area of ​​an inner wall of the housing;

[0012] A first heating component, wherein the first heating component is bent along the circumferential direction of the inner wall of the shell and is disposed on the first base film;

[0013] The first heating assembly includes a plurality of heating wire groups.

[0014] In a feasible implementation manner, the second heating film includes:

[0015] A second base film, wherein the second base film is a flexible base film and is arranged in a ring shape at the surface edge of the second electrode;

[0016] A second heating component, the second heating component is arranged on the second base film, and the second heating component is annular and arranged concentrically with the second base film;

[0017] The second heating assembly includes a plurality of heating wire groups.

[0018] In a feasible implementation manner, the control component includes:

[0019] A temperature measuring circuit module is arranged on the inner wall of the shell, and is used for outputting a voltage that changes accordingly according to temperature changes.

[0020] In a feasible implementation manner, the temperature measurement circuit module includes:

[0021] a thermistor, the thermistor being used to measure the temperature inside the housing;

[0022] A detection circuit is connected to the thermistor, the detection circuit includes a voltage divider circuit and an amplifier circuit, and the detection circuit is used to detect and amplify the voltage divided by the thermistor.

[0023] In a feasible implementation manner, the control component further includes:

[0024] A heating power module, the heating power module is connected to the first heating film and the second heating film, the heating power module includes a voltage divider circuit, a voltage comparison circuit, a shaping circuit and a transistor, and the heating power module is used to control the voltage of the first heating film and the second heating film according to the preset temperature and the voltage output by the temperature measurement circuit module.

[0025] In a feasible implementation manner, the sensor component further includes:

[0026] A first conductive hole, wherein the first conductive hole is opened on the first electrode;

[0027] a second conductive hole, wherein the second conductive hole is opened on the second electrode;

[0028] A conductive member, one end of which is connected to the first electrode through a first conductive hole, and the other end of which is connected to the second electrode through a second conductive hole.

[0029] In a feasible implementation manner, the second electrode includes:

[0030] A first clamping member, wherein the first clamping member is an insulating ring-shaped member;

[0031] A second clamping member, wherein the second clamping member is an insulating ring-shaped member, and the second clamping member is connected to the first clamping member;

[0032] A conductive film is disposed at a connection between the first clamping member and the second clamping member, and the conductive film is clamped between the first clamping member and the second clamping member.

[0033] In a feasible implementation manner, the first electrode includes:

[0034] Pedestal;

[0035] A conductive coating, wherein the conductive coating is disposed on a side of the base facing the second electrode, and an area of ​​the conductive coating is smaller than a projected area of ​​the first electrode;

[0036] A capacitance conversion module, the capacitance conversion module is arranged on a side of the base facing away from the second electrode, and the capacitance conversion module is used to convert a capacitance signal into a voltage signal;

[0037] A conductive rod is disposed inside the base, and the conductive rod connects the conductive coating and the capacitance conversion module.

[0038] In a feasible implementation manner, the first electrode further includes:

[0039] There are multiple heat dissipation holes, which are opened at the edge of the first electrode and are arranged around the conductive coating.

[0040] The present application provides a constant temperature capacitive pressure sensing device, comprising: a sensing component, the sensing component comprising a housing, a first electrode and a second electrode, the first electrode and the second electrode being arranged in the housing; a first heating film, the first heating film being arranged on the inner wall of the housing; a second heating film, the second heating film being arranged on the surface of the second electrode; a control component, the control component being connected to the first heating film and the second heating film, the control component being used to measure the temperature in the housing, and to control the voltage of the first heating film and the second heating film according to a preset temperature. The present application effectively reduces the influence of ambient temperature fluctuations on the detection accuracy of the capacitive pressure sensor by respectively arranging the first heating film and the second heating film on the inner wall of the housing and the surface of the second electrode, and combining the control component to accurately control the temperature inside the housing. The control component can monitor the temperature in the housing in real time, and automatically adjust the voltage of the heating film according to the preset temperature, so as to realize active control of the working environment of the sensor. This design ensures that the sensor works under constant temperature conditions, thereby greatly improving the accuracy and stability of pressure measurement. The constant temperature environment helps to reduce the capacitance drift caused by temperature changes, thereby maintaining the stability of the zero point of the sensor. This is especially important for application scenarios that require long-term stable operation and high-precision measurement, ensuring the reliability and consistency of the measurement results.

[0041] Other features and advantages of the present application will be described in the following description, and partly become apparent from the description, or be understood by practicing the present application. The purpose and other advantages of the present application can be realized and obtained by the structures specifically pointed out in the written description, claims, and drawings.

[0042] The technical solution of the present application is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0044] Figure 1 The overall structural diagram of a constant temperature capacitive pressure sensor device provided in an embodiment of the present application is shown;

[0045] Figure 2 A schematic diagram of the structure of a first heating film provided in an embodiment of the present application is shown;

[0046] Figure 3 A schematic diagram of the structure of a second heating film provided in an embodiment of the present application is shown;

[0047] Figure 4A schematic diagram of a top view of the structure of a first electrode provided in an embodiment of the present application is shown;

[0048] Figure 5 A bottom-up structural schematic diagram of a first electrode provided in an embodiment of the present application is shown;

[0049] Figure 6 A schematic diagram of the structure of the second electrode provided in an embodiment of the present application is shown;

[0050] Figure 7 A schematic diagram of the structure of a control component provided in an embodiment of the present application is shown;

[0051] Figure 8 A schematic diagram of the structure of a detection circuit provided in an embodiment of the present application is shown;

[0052] Fig. 9 A schematic diagram of the structure of a heating power module provided in an embodiment of the present application is shown.

[0053] In the figure:

[0054] 1. First heating film; 11. First base film; 12. First heating component; 2. Second heating film; 21. Second base film; 22. Second heating component; 3. First electrode; 31. Base; 32. Conductive coating; 33. Capacitance conversion module; 34. Conductive rod; 35. Heat dissipation hole; 36. First conductive hole; 4. Second electrode; 41. First clamping piece; 42. Second clamping piece; 43. Conductive film; 44. Second conductive hole; 5. Control component; 6. Housing; 7. Conductive piece. DETAILED DESCRIPTION

[0055] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0056] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0057] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0058] See also Figure 1 , shows a schematic diagram of the overall structure of a constant temperature capacitive pressure sensor device provided in an embodiment of the present application, including:

[0059] The sensor assembly comprises a housing 6, a first electrode 3 and a second electrode 4, wherein the first electrode 3 and the second electrode 4 are arranged in the housing 6;

[0060] A first heating film 1, which is arranged on the inner wall of the housing 6;

[0061] A second heating film 2, which is arranged on the surface of the second electrode 4;

[0062] The control component 5 is connected to the first heating film 1 and the second heating film 2. The control component 5 is used to measure the temperature inside the housing 6 and control the voltage of the first heating film 1 and the second heating film 2 according to a preset temperature.

[0063] In the above embodiment, the sensing component is the core part of the present application, including a housing and a first electrode 3 and a second electrode 4 arranged in the housing. A capacitor is formed between the two electrodes to sense pressure changes. The first heating film 1 is arranged on the inner wall of the housing to provide heat; the second heating film 2 is arranged on the surface of the second electrode 4 to participate in temperature control. The control component 5 is connected to the first heating film 1 and the second heating film 2, and is responsible for measuring the temperature in the housing and adjusting the voltage of the two heating films according to a preset temperature value. By adjusting the voltage, the control component 5 can control the heating power of the heating film, thereby achieving precise temperature control.

[0064] Through the combined action of the first heating film 1 and the second heating film 2, and the precise regulation of the control component 5, the device can maintain a stable operating temperature of the sensing component under different environments. This is crucial to improving the measurement accuracy and stability of the capacitive pressure sensor, because temperature fluctuations may affect the characteristics of the capacitor and the performance of the sensor. After the temperature is stabilized, the capacitance performance of the sensing component 5 is more stable, thereby improving the accuracy of the pressure measurement. This is particularly important for application scenarios that require high-precision measurements.

[0065] See also Figure 2, shows a schematic structural diagram of a first heating film provided in an embodiment of the present application. Further, the first heating film 1 includes:

[0066] A first base film 11, which is a flexible base film, and an area of ​​the first base film 11 is less than or equal to an area of ​​an inner wall of the housing 6;

[0067] A first heating component 12, the first heating component 12 is bent along the circumferential direction of the inner wall of the housing 6 and is disposed on the first base film 11;

[0068] The first heating assembly 12 includes a plurality of heating wire groups.

[0069] In the above embodiment, the first base film 11 is a flexible base film, and its area is less than or equal to the area of ​​the inner wall of the shell 6, which means that the first base film 11 can fit the inner wall of the shell 6 without exceeding its boundary. The first heating component 12 is embedded in the first base film 11, and it is arranged along the circumference of the inner wall of the shell 6, that is, the first heating component 12 is parallel to both ends of the shell 6. The first heating component 12 is composed of a plurality of heating wire groups, which can work together to generate heat.

[0070] Since the first base film 11 is flexible and its area is equal to the area of ​​the inner wall of the shell 6, the first heating film 1 can be easily adapted and attached to shells 6 of various shapes and sizes. The first heating assembly 12 is arranged along the circumferential bending of the inner wall of the shell 6 and is composed of a plurality of heating wire groups. This design can ensure that the heat is evenly distributed on the inner wall of the shell 6, avoiding the problem of local overheating or uneven temperature. Since the structure of the first heating film 1 is relatively simple and can be easily attached to the shell 6, its installation and replacement process is also relatively simple and convenient.

[0071] See also Figure 3 , shows a schematic structural diagram of the second heating film provided in an embodiment of the present application. Further, the second heating film 2 includes:

[0072] A second base film 21, which is a flexible base film and is arranged in a ring shape at the surface edge of the second electrode 4;

[0073] A second heating component 22, which is disposed on the second base film 21, and is annular and concentric with the second base film 21;

[0074] The second heating assembly 22 includes a plurality of heating wire groups.

[0075] In the above embodiment, the second base film 21 is also a flexible base film, which can adapt to different shapes or surfaces. The second base film 21 is annular and fits the surface edge of the second electrode 4, that is, forms a circular ring film on the surface of the second electrode 4. The second heating component 22 is arranged on the second base film 21 and is directly embedded in the base film to ensure that heat can be effectively transferred to the base film and further distributed to the surrounding environment.

[0076] The layout of the second heating assembly 22 matches the annular design of the second base film 21, which helps maintain uniformity and efficiency of heating. The annular design and concentrically arranged heating assemblies help achieve a more uniform heating effect and avoid the problem of heat concentration or insufficient heat. The second heating assembly 22 is composed of multiple heating wire groups. Through the independent or coordinated work of multiple heating wire groups, the heating intensity and mode can be adjusted as needed, thereby providing more precise temperature control.

[0077] See also Figure 7 , shows a schematic diagram of the structure of the control component provided in an embodiment of the present application. Further, the control component 5 includes:

[0078] The temperature measuring circuit module is arranged on the inner wall of the housing 6, and is used for outputting a voltage that changes accordingly according to temperature changes.

[0079] In the above embodiment, the temperature measuring circuit module is installed on the inner surface of the housing, which means that it can directly contact the air inside the housing, thereby accurately measuring its temperature. The core function of the temperature measuring circuit module is to output a voltage value corresponding to the temperature value it measures.

[0080] By setting the temperature measurement circuit module directly on the inner wall of the housing, direct and accurate measurement of the internal temperature can be achieved. The temperature measurement circuit module can output a voltage value corresponding to the temperature in real time, which provides timely temperature information for the control system. This helps the system to quickly respond to temperature changes and adjust the heating or cooling strategy to keep the device or system running within the set temperature range.

[0081] See also Figure 8 , shows a schematic diagram of the structure of the detection circuit provided in an embodiment of the present application, further, the temperature measurement circuit module includes:

[0082] Thermistor, the thermistor is used to measure the temperature inside the housing 6;

[0083] The detection circuit is connected to the thermistor. The detection circuit includes a voltage divider circuit and an amplifier circuit. The detection circuit is used to detect and amplify the voltage divided by the thermistor.

[0084] In the above embodiment, the temperature measurement circuit module is composed of a thermistor and a detection circuit, and the detection circuit includes a voltage divider circuit and an amplifier circuit. The implementation principle is to use the thermistor RT as a temperature sensor. As the temperature increases, the resistance of the thermistor RT also increases accordingly. In the process of internal temperature changes, a corresponding changing voltage U1 is output through the detection circuit.

[0085] By combining the voltage divider circuit and the amplifier circuit, the sensitivity of the temperature measurement circuit module to temperature changes can be greatly improved, thereby achieving accurate temperature measurement. The design of the voltage divider circuit can reduce the impact of power supply voltage fluctuations on the measurement results, thereby improving the stability of the temperature measurement circuit module. The design of the temperature measurement circuit module is relatively simple and easy to integrate with other electronic components or systems. At the same time, by adjusting the parameters of the voltage divider circuit and the amplifier circuit, measurements of different temperature ranges can also be achieved, which has strong scalability.

[0086] See also Fig. 9 , shows a schematic diagram of the structure of the heating power module provided in an embodiment of the present application. Further, the control component 5 also includes:

[0087] A heating power module is connected to the first heating film 1 and the second heating film 2. The heating power module includes a voltage divider circuit, a voltage comparison circuit, a shaping circuit and a transistor. The heating power module is used to control the voltage of the first heating film 1 and the second heating film 2 according to the preset temperature and the voltage output by the temperature measurement circuit module.

[0088] In the above embodiment, the control component 5 includes a heating power module, and the heating power module includes a voltage comparison circuit, a shaping circuit and a transistor, wherein the transistor can be a MOS tube. The main function of the heating power module is to control the voltage applied to the first heating film 1 and the second heating film 2 according to the voltage output by the temperature measurement circuit module. Specifically, the preset temperature is the final temperature that the sensor is to reach. If the preset temperature of the sensor is 100 degrees, the corresponding resistance value is R according to the resistance table of the thermistor, and R is substituted into the detection circuit, and the calculated voltage value is the preset voltage U0. U0 is obtained through the voltage divider circuit, and U0 and U1 are respectively introduced into the voltage comparator for comparison, and the high and low levels U2 are output. The shaping circuit is connected in series with the MOS tube, and the G pins of both are connected to U2. U2 will repeatedly switch between high and low levels according to the comparison results of U0 and U1, causing the shaping circuit and the MOS tube to be repeatedly turned on and off. By utilizing the process in which the Rds resistance of the MOS tube gradually increases as VGS (U2) becomes lower, a small adjustment effect is achieved on the heating wire path, which can prevent excessive overshoot during the temperature control process.

[0089] Through the voltage comparison circuit, the heating power module can accurately adjust the voltage of the heating film according to the voltage temperature information provided by the temperature measurement circuit module, thereby achieving precise control of the temperature. This is particularly important for application scenarios that require precise temperature control. As an electronic switch, the MOS tube controls its conduction and cutoff according to the high and low levels U2 output by the voltage comparator. When U2 is at a high level, the MOS tube is turned on, allowing current to pass through the heating film; when U2 is at a low level, the MOS tube is cut off, preventing current from flowing to the heating film. This switching characteristic enables the heating power module to accurately control the heating power of the heating film according to the voltage output by the temperature measurement circuit module. Another important function of the MOS tube is to achieve fine-tuning of the heating power through the change of its Rds resistance. When U2 becomes lower, the Rds resistance of the MOS tube gradually increases, which will cause the current passing through the heating film to decrease, thereby reducing the heating power. This fine-tuning effect helps prevent overshoot during temperature control, so that the temperature of the sensor can more smoothly approach and maintain the preset temperature.

[0090] Furthermore, the sensor component also includes:

[0091] A first conductive hole 36, the first conductive hole 36 is opened on the first electrode 3;

[0092] A second conductive hole 44, which is opened on the second electrode 4;

[0093] Conductive member 7 , one end of the conductive member 7 is connected to the first electrode 3 through the first conductive hole 36 , and the other end of the conductive member 7 is connected to the second electrode 4 through the second conductive hole 44 .

[0094] In the above embodiment, the conductive member 7 is used to connect the first electrode 3 and the second electrode 4. It has good conductivity. One end of the conductive member 7 is connected to the first electrode 3 through the first conductive hole 36, and the other end is connected to the second electrode 4 through the second conductive hole 44, thereby realizing electrical connection between the two electrodes.

[0095] By opening conductive holes on the first electrode 3 and the second electrode 4 respectively and connecting them with the conductive member 7, the overall stability of the sensor assembly can be enhanced. Because the conductive member 7 is tightly connected to the electrode through the hole, it is not easy to loosen or fall off. The conductive member 7, as a direct connection channel between the two electrodes, can significantly improve the transmission efficiency of the electrical signal. This direct connection reduces the attenuation and interference of the signal during the transmission process, so that the sensor assembly can respond to external signals more accurately.

[0096] See also Figure 6 , shows a schematic structural diagram of the second electrode provided in an embodiment of the present application. Further, the second electrode 4 includes:

[0097] A first clamping member 41, which is an insulating ring-shaped member;

[0098] A second clamping member 42, which is an insulating ring-shaped member and is connected to the first clamping member 41;

[0099] The conductive film 43 is disposed at the connection between the first clamping member 41 and the second clamping member 42 , and the conductive film 43 is clamped between the first clamping member 41 and the second clamping member 42 .

[0100] In the above embodiment, the first clamping member 41 is an insulating ring-shaped member having a central opening, mainly for providing a stable support structure and connecting with other components. The second clamping member 42 is also an insulating ring-shaped member having similar shape characteristics to the first clamping member. The conductive film 43 is clamped between the first clamping member 41 and the second clamping member 42, and the three are connected into a whole by sintering.

[0101] The use of the insulating ring enhances the sealing of the sensor structure. In the capacitive film pressure sensor, the sealing of the vacuum pressure detection chamber is crucial for accurate measurement. The insulating ring is tightly combined with the strain film through high-temperature sintering and curing to form a stable and sealed structure, which effectively prevents interference from the external environment and improves the long-term stability and reliability of the sensor. The first clamping member 41 and the second clamping member 42 effectively isolate the conductive film 43 from the metal shell and other metal parts. This isolation avoids the noise and parasitic capacitance that may be introduced when the conductive film 43 is directly embedded in the shell, thereby reducing signal interference and improving the signal-to-noise ratio and measurement accuracy of the sensor.

[0102] See also Figure 4 and Figure 5 , shows a schematic structural diagram of the first electrode provided in an embodiment of the present application. Further, the first electrode 3 includes:

[0103] Base 31;

[0104] A conductive coating 32, which is disposed on a side of the base 31 facing the second electrode 4, and an area of ​​the conductive coating 32 is smaller than a projected area of ​​the first electrode 3;

[0105] A capacitance conversion module 33, which is disposed on a side of the base 31 facing away from the second electrode 4, and is used to convert a capacitance signal into a voltage signal;

[0106] The conductive rod 34 is disposed inside the base 31 , and the conductive rod 34 connects the conductive coating 32 and the capacitance conversion module 33 .

[0107] In the above embodiment, the base 31 is the main structure of the first electrode and provides support for other components. The conductive coating 32 is arranged on the side of the base facing the second electrode 4, so that a capacitance gap is formed between the two. When external pressure acts, this gap will change, thereby changing the capacitance value. The capacitance conversion module 33 is arranged on the side of the base facing away from the second electrode 4, and converts the capacitance change caused by the pressure change into a voltage signal. The conductive rod 34 is arranged inside the base and connects the conductive coating 32 and the capacitance conversion module 33.

[0108] By accurately designing the area and shape of the conductive coating 32, as well as the gap between it and the second electrode 4, the change of the external pressure can be captured more sensitively and converted into a change of the capacitance value. The capacitance conversion module further converts these changes into voltage signals, thereby improving the accuracy of the measurement. The capacitance conversion module is arranged on the side of the base 31 facing away from the second electrode 4, which not only avoids the interference of the module on the capacitance gap, but also makes the structure of the entire first electrode 3 more compact and reasonable. The setting of the conductive rod 34 ensures the stable transmission of the signal between the conductive coating 32 and the capacitance conversion module 33, and reduces the measurement error caused by poor contact or signal attenuation.

[0109] Furthermore, the first electrode 3 further includes:

[0110] There are multiple heat dissipation holes 35 , which are opened at the edge of the first electrode 3 and are arranged around the conductive coating 32 .

[0111] In the above embodiment, the present application has a plurality of heat dissipation holes 35 , which are arranged around the conductive coating 32 at the edge of the first electrode 3 .

[0112] The setting of the heat dissipation holes can significantly improve the thermal stability of the present application. Under long-term working conditions, the heat generated by the heating film will increase. If this heat cannot be dissipated in time, it may affect the measurement accuracy of the capacitive pressure sensor and even cause the electrode performance to deteriorate or be damaged. The heat dissipation holes can effectively conduct heat away, thereby keeping the electrode within a relatively stable operating temperature range, thereby reducing the measurement error caused by temperature changes.

[0113] The present application provides a constant temperature capacitive pressure sensing device, comprising: a sensing component, the sensing component comprising a housing 6, a first electrode 3 and a second electrode 4, the first electrode 3 and the second electrode 4 being arranged in the housing 6; a first heating film 1, the first heating film 1 being arranged on the inner wall of the housing 6; a second heating film 2, the second heating film 2 being arranged on the surface of the second electrode 4; a control component 5, the control component 5 being connected to the first heating film 1 and the second heating film 2, the control component 5 being used to measure the temperature in the housing 6, and to control the voltage of the first heating film 1 and the second heating film 2 according to a preset temperature. The present application arranges the first heating film 1 and the second heating film 2 on the inner wall of the housing 6 and the surface of the second electrode 4, respectively, and combines the control component to accurately control the internal temperature of the housing 6, thereby effectively reducing the influence of ambient temperature fluctuations on the detection accuracy of the capacitive pressure sensor. The control component can monitor the temperature in the housing in real time, and automatically adjust the voltage of the heating film according to the preset temperature, so as to realize active control of the working environment of the sensor. This design ensures that the sensor works under constant temperature conditions, thereby greatly improving the accuracy and stability of pressure measurement. The constant temperature environment helps to reduce the capacitance drift caused by temperature changes, thereby maintaining the stability of the zero point of the sensor. This is especially important for application scenarios that require long-term stable operation and high-precision measurement, ensuring the reliability and consistency of the measurement results.

[0114] Those skilled in the art will appreciate that the accompanying drawings are only schematic diagrams of a preferred implementation scenario, and the modules or processes in the accompanying drawings are not necessarily necessary for implementing the present application. Those skilled in the art will appreciate that the modules in the devices in the implementation scenario can be distributed in the devices of the implementation scenario according to the description of the implementation scenario, or can be changed accordingly and located in one or more devices different from the present implementation scenario. The modules of the above-mentioned implementation scenario can be combined into one module, or can be further split into multiple submodules.

[0115] The above serial numbers of this application are only for description and do not represent the advantages and disadvantages of the implementation scenarios. The above disclosure is only a few specific implementation scenarios of this application, but this application is not limited to them, and any changes that can be thought of by technicians in this field should fall within the scope of protection of this application.

Claims

1. A constant temperature capacitive pressure sensing device, characterized in that: include: A sensor assembly, the sensor assembly comprising a housing, a first electrode and a second electrode, wherein the first electrode and the second electrode are arranged in the housing; a first heating film, wherein the first heating film is arranged on the inner wall of the housing; a second heating film, wherein the second heating film is arranged on a surface of the second electrode; A control component is connected to the first heating film and the second heating film, and is used to measure the temperature inside the housing and control the voltage of the first heating film and the second heating film according to a preset temperature.

2. The device according to claim 1, characterized in that The first heating film comprises: a first base film, wherein the first base film is a flexible base film, and an area of ​​the first base film is smaller than or equal to an area of ​​an inner wall of the housing; A first heating component, wherein the first heating component is bent along the circumferential direction of the inner wall of the shell and is disposed on the first base film; The first heating assembly includes a plurality of heating wire groups.

3. The device according to claim 1, characterized in that The second heating film comprises: A second base film, wherein the second base film is a flexible base film and is arranged in a ring shape at the surface edge of the second electrode; A second heating component, the second heating component is arranged on the second base film, and the second heating component is annular and concentrically arranged with the second base film; The second heating assembly includes a plurality of heating wire groups.

4. The device according to claim 1, characterized in that The control component comprises: A temperature measuring circuit module is arranged on the inner wall of the shell, and is used for outputting a voltage that changes accordingly according to temperature changes.

5. The device according to claim 4, characterized in that The temperature measurement circuit module comprises: a thermistor, the thermistor being used to measure the temperature inside the housing; A detection circuit is connected to the thermistor, the detection circuit includes a voltage divider circuit and an amplifier circuit, and the detection circuit is used to detect and amplify the voltage divided by the thermistor.

6. The device according to claim 4, characterized in that The control component also includes: A heating power module, the heating power module is connected to the first heating film and the second heating film, the heating power module includes a voltage divider circuit, a voltage comparison circuit, a shaping circuit and a transistor, and the heating power module is used to control the voltage of the first heating film and the second heating film according to the preset temperature and the voltage output by the temperature measurement circuit module.

7. The device according to claim 1, characterized in that The sensor assembly also includes: a first conductive hole, wherein the first conductive hole is opened on the first electrode; a second conductive hole, wherein the second conductive hole is opened on the second electrode; A conductive member, one end of which is connected to the first electrode through a first conductive hole, and the other end of which is connected to the second electrode through a second conductive hole.

8. The device according to claim 1, characterized in that The second electrode comprises: A first clamping member, wherein the first clamping member is an insulating ring-shaped member; A second clamping member, wherein the second clamping member is an insulating ring-shaped member, and the second clamping member is connected to the first clamping member; A conductive film is disposed at a connection between the first clamping member and the second clamping member, and the conductive film is clamped between the first clamping member and the second clamping member.

9. The device according to claim 1, characterized in that The first electrode comprises: Pedestal; A conductive coating, wherein the conductive coating is disposed on a side of the base facing the second electrode, and an area of ​​the conductive coating is smaller than a projected area of ​​the first electrode; A capacitance conversion module, the capacitance conversion module is arranged on a side of the base facing away from the second electrode, and the capacitance conversion module is used to convert a capacitance signal into a voltage signal; A conductive rod is disposed inside the base, and the conductive rod connects the conductive coating and the capacitance conversion module.

10. The device according to claim 9, characterized in that The first electrode further comprises: There are multiple heat dissipation holes, which are opened at the edge of the first electrode and are arranged around the conductive coating.

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