Pressure sensor

Abstract

The invention discloses a pressure sensor, relates to the technical field of pressure sensors, and aims to solve the technical problem that an output signal of the pressure sensor is easy to drift at high temperature, the pressure sensor comprises a pressure sensor main body, one end of the pressure sensor main body is provided with an output port, and the other end of the pressure sensor main body is provided with a disc body fixing end. A chuck is mounted at the fixed end of the chuck body, a diaphragm is arranged in the center area of the chuck, and a stress compensation structure, a protective jacket, an air pressure adjusting structure, an impurity filtering structure, an impurity discharging part and a secondary filtering layer are arranged on the side, close to the pressure sensor body, of the diaphragm. Signal drifting of the pressure sensor is effectively prevented, it is ensured that pressure measurement is still accurate and reliable in a complex temperature environment, self-adaptive air pressure adjustment can be achieved, and meanwhile the effect of preventing impurities from affecting a diaphragm of the sensor can be achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of pressure sensors, and more particularly, to a pressure sensor. Background Art

[0002] In the fields of industrial automation, aerospace, and environmental monitoring, pressure sensors serve as key signal acquisition components, and their performance stability directly affects the reliability and measurement accuracy of the system. Among them, chuck diaphragm pressure sensors are widely used due to their compact structure and sensitive response. However, when faced with extreme temperature environments, the defects of traditional structural design lead to a serious decline in their performance, which has become a technical bottleneck that restricts the expansion of the scope of application. The chuck diaphragm pressure sensor senses external pressure through the diaphragm and transmits the pressure change to the sensitive element to realize signal conversion. However, in actual applications, extreme temperature environments (such as the temperature difference environment of -40℃~600℃ next to the high-temperature furnace in the metallurgical industry and the extremely low temperature environment of polar scientific research equipment) pose a severe challenge to the stability of the sensor. Traditional sensors use a structure that combines a stainless steel diaphragm with sensitive elements such as strain gauges. Due to the significant difference in the thermal expansion coefficient between stainless steel and the base material of the sensitive element (the thermal expansion coefficient of stainless steel is about 17×10⁻ 6 / ℃, while the base material of some sensitive components is only 5×10⁻ 6 When the temperature rises, the thermal stress generated by the rapid expansion of the stainless steel diaphragm causes additional tensile force on the strain gauge attached to its backside. This can lead to failure of the adhesive layer between the strain gauge and the diaphragm, causing the strain gauge to fall off, or cause the base material to soften and deform, resulting in sensor output signal drift. In light of this, we propose a pressure sensor. Summary of the Invention

[0003] The object of the present invention is to provide a pressure sensor to solve the technical problem that the output signal of the pressure sensor is prone to drift under high temperature conditions.

[0004] To solve the above technical problems, the present invention provides the following technical solution: a pressure sensor comprising a pressure sensor body, wherein one end of the pressure sensor body is provided with an output port, the other end of the pressure sensor body is provided with a disk fixed end, a chuck is mounted on the end of the disk fixed end, a diaphragm is provided in the center area of ​​the chuck, and a stress compensation structure is provided on the side of the diaphragm close to the pressure sensor body; The stress compensation structure includes a thin sheet, which is located between the diaphragm and the sensitive element inside the pressure sensor body. The thin sheet is made of a shape memory polymer. A honeycomb cavity group is provided between the thin sheet and the diaphragm to enhance the overall strength of the diaphragm. A protective cover is installed on the side of the chuck away from the pressure sensor body, and multiple air pressure regulating structures are installed on the protective cover.

[0005] Preferably, the honeycomb cavity group is composed of a plurality of closely arranged chips, the chips are in the shape of a regular hexagon, the chips are made of a polymer material with a low thermal expansion coefficient, and the interior of the chips is hollow and filled with a phase change material.

[0006] Preferably, the protective jacket is a hollow conical structure, the fixed end of the protective jacket and the chuck is a small-diameter end, and the other side of the protective jacket is sealed and equipped with multiple gas channels.

[0007] Preferably, the air pressure regulating structure includes a compensation port opened on the side wall of the protective jacket, a deformable sac is installed inside the compensation port, the deformable sac is a hollow semi-elliptical, the deformable sac is made of a highly elastic material, a through opening is opened in the center of one side of the deformable sac, and a plurality of clamping angles are installed on the inner circumference of the through opening.

[0008] Preferably, the plurality of air pressure regulating structures are distributed in an array, and the plurality of air pressure regulating structures are proportionally reduced from the large end to the small end.

[0009] Preferably, the gas channel is provided with a debris filtering structure, which includes a debris filtering sleeve. The debris filtering sleeve is conical in shape, and a plurality of debris passing grooves and debris discharging grooves are respectively provided on the inner and outer sides of the debris filtering sleeve. A debris blocking cone head is installed at the input end of the debris filtering sleeve, and a debris receiving warping ring plate is installed along the inner bottom side of the debris passing groove.

[0010] Preferably, the connecting warping ring plate is in the form of a ring body, and the connecting warping ring plate has a warping cross-section with increasing height from the outside to the center and a curvature, and a plurality of medium passages are opened on the connecting warping ring plate.

[0011] Preferably, a debris removal piece is provided between the debris removal groove and the adjacent debris passing groove, and the debris removal piece includes a ball groove opened on the debris filtering sleeve, a center ball is provided in the center of the ball groove, the center of the center ball is connected to a center shaft rotatably connected to the ball groove, and the outer periphery of the center ball is connected to a plurality of side rings, and the outer periphery of the side rings is in contact with the inner wall of the ball groove.

[0012] Preferably, a secondary filter layer is provided on the inner periphery of the protective outer sleeve, and the secondary filter layer is provided with a filter mesh layer, an activated carbon mesh layer and an ion exchange membrane layer in sequence from the outside to the inside. The secondary filter layer is a protruding pointed cone as a whole, and a plurality of spiral grooves are provided on the surface of the filter mesh layer.

[0013] Preferably, the gas channel includes an air inlet expansion end, one end of the air inlet expansion end is connected to a necking end, one side of the necking end is provided with an exhaust head, the adjacent side of the necking end and the exhaust head is connected to the filter sleeve, and the necking end is connected to a return suction pipe, and the return suction pipe corresponds to the position of the spiral groove.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention adopts an innovative stress compensation structure designed for the pressure sensor, which is composed of a shape memory polymer sheet and a honeycomb cavity group. The regular hexagonal chips with low thermal expansion coefficient in the honeycomb cavity group are closely arranged, which can evenly disperse the pressure on the diaphragm, avoid local stress concentration, and enhance the overall strength of the diaphragm. The phase change material filled in the chip can undergo a solid-liquid phase transition when the temperature changes, buffering temperature fluctuations. Under the synergistic effect of the two, when the temperature changes and the diaphragm and the sensitive element generate additional stress due to different degrees of expansion or contraction, the shape memory polymer sheet can offset the stress through pre-designed deformation. For example, at high temperature, the expansion of the diaphragm generates tensile stress on the sensitive element, and the expansion of the sheet generates a reverse force, which reduces the stress on the sensitive element and effectively prevents signal drift. This ensures that the pressure measurement is still accurate and reliable in complex temperature environments, and solves the problem that the output signal of the pressure sensor is prone to drift under high temperature conditions.

[0015] 2. The present invention also uses a pressure self-regulating conical protective sleeve structure based on the deformation of shape memory polymer sheets, which can sensitively sense the pressure difference caused by temperature changes and automatically adjust. When the temperature rises, the sheet expands and squeezes the air around the diaphragm, causing the air pressure inside the protective sleeve to change. At this time, the deformable capsule in the pressure regulating structure will flexibly deform according to the size of the pressure difference. When the pressure difference is large, the deformable capsule will deform significantly, and the corners will open a larger gap to quickly balance the air pressure; when the pressure difference is small, it will deform slightly and finely adjust the gas flow rate to always maintain the stable air pressure inside the protective sleeve. This adaptive adjustment mechanism avoids the interference of pressure fluctuations on the diaphragm, creates a stable internal pressure environment for the sensor, and enables it to operate stably under working conditions with changing pressure.

[0016] 3. The present invention also plays a primary filtering role through the impurity filtering structure on the gas channel, effectively blocking impurities in the medium. The impurity filtering sleeve disperses the impurities in the medium to the periphery through the impurity blocking cone head. The impurity receiving ring plate gradually blocks the impurities and guides them into the impurity removal groove for centralized collection by virtue of its unique raised slope design. When the impurities accumulate to a certain extent, the flow of the medium drives the side ring of the impurity removal part to rotate, and the impurities are transported to the impurity removal groove for automatic discharge, realizing continuous filtration. This structure effectively intercepts larger particles of impurities, prevents them from entering the interior of the sensor, reduces the damage of impurities to the diaphragm, and provides a basic guarantee for the normal operation of the sensor.

[0017] 4. The present invention also deeply purifies the medium through a secondary filtration layer on the inner periphery of the protective outer shell. The secondary filtration layer is composed of a filter mesh layer, an activated carbon mesh layer and an ion exchange membrane layer. The filter mesh layer filters tiny and residual impurities. The activated carbon mesh layer uses nano-scale pores and a huge specific surface area to adsorb organic impurities and some metal ions. The ion exchange membrane layer selectively captures specific ions, such as chloride ions and sulfate ions. The three-layer structure works synergistically to purify the medium from different levels, remove substances that may corrode the diaphragm or affect the measurement, ensure that the medium entering the vicinity of the diaphragm is highly pure, and further improve the measurement accuracy and service life of the sensor.

[0018] 5. The present invention also adopts a unique circulation filtration design, through the spiral groove, air inlet expansion head, necking end and return suction pipe working together to enhance the impurity filtering effect. The air inlet expansion head guides the fluid to accelerate smoothly, the necking end uses the Bernoulli principle to increase the flow rate, and generates suction at the end of the return suction pipe to suck back the tiny and residual impurities filtered by the secondary filtration layer to the filtration stage, realizing circulation filtration. At the same time, the increase in flow rate at the necking end assists the filter sleeve to improve the impurity separation efficiency, so that the medium can more effectively separate impurities from the medium when passing through the filter sleeve. The circulation filtration mechanism ensures that impurities are fully filtered, continuously provides a clean working environment for the sensor, and ensures its long-term stable and accurate operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 This is a schematic diagram of the positive axis side structure of the present invention; Figure 2 This is a schematic diagram of the bottom shaft side structure of the present invention; Figure 3 A schematic structural diagram of a half-cut chuck portion of the present invention; Figure 4 Schematic diagram of the split structure of the stress compensation structure of the present invention; Figure 5 A schematic diagram of a half-section structure of the arrangement and distribution of multiple deformable capsules in the present invention; Figure 6 Schematic diagram of the structure of the gas channel in the present invention; Figure 7 Schematic diagram of the internal structure of the impurity filtering structure of the present invention; Figure 8 Schematic diagram of the structure of the debris removal unit in the present invention; Figure 9 Schematic diagram of the structure of the secondary filtration layer in the present invention; Figure 10 Schematic diagram of the structure between the gas channel and the spiral groove in the present invention.

[0020] Description of the numbers in the figure: 1. Pressure sensor body; 2. Output port; 3. Fixed end of the disc; 4. Chuck; 5. Diaphragm; 6. Stress compensation structure; 7. Protective cover; 8. Air pressure regulating structure; 9. Gas channel; 10. Filter structure; 11. Filter element; 12. Secondary filter layer; 601, thin sheet; 602, chip; 811, compensation port; 812, deformation capsule; 813, clamping angle; 901, air inlet expansion port; 902, necking end; 903, exhaust head; 904, return suction pipe; 101, impurity filter sleeve; 102, impurity passing groove; 103, impurity discharge groove; 104, impurity retaining cone head; 105, impurity receiving ring plate; 111, ball groove; 112, center ball; 113, center axis; 114, side ring; 121, filter mesh layer; 122, activated carbon mesh layer; 123, ion exchange membrane layer; 124, spiral groove. DETAILED DESCRIPTION

[0021] like Figures 1 to 10 As shown, the present invention relates to a pressure sensor, including a pressure sensor body 1, which serves as a core carrier and has an integrated output port 2 at one end; a disk fixed end 3 is provided at the other end, and the fixed end adopts an adaptive mounting structure, and a chuck 4 is fixedly installed at the end to provide stable support for the installation and positioning of the sensor and external equipment. A diaphragm 5 is embedded in the central area of ​​the chuck 4. As part of the pressure sensitive element, the diaphragm 5 converts external pressure into a mechanical signal through deformation, which is then transmitted to the conversion unit inside the sensor body to achieve accurate measurement of pressure parameters and signal conversion. A stress compensation structure 6 is provided on the side of the diaphragm 5 close to the pressure sensor body 1. The stress compensation structure 6 includes a thin sheet 601. The thin sheet 601 is between the diaphragm 5 and the sensitive element inside the pressure sensor body 1. The thin sheet 601 is made of a shape memory polymer. A honeycomb cavity group is provided between the thin sheet 601 and the diaphragm 5 for enhancing the overall strength of the diaphragm 5. The honeycomb cavity group is composed of a plurality of closely arranged chips 602. The chip 602 is in the shape of a regular hexagon and is made of a polymer material with a low thermal expansion coefficient. The honeycomb cavity group made of a polymer material with a low thermal expansion coefficient has a very small structural size change due to temperature change. The interior of the chip 602 is hollow and filled with a phase change material. The phase change material can be selected from materials such as paraffin.

[0022] The regular hexagonal chips 602 are arranged closely and regularly, providing uniform support for the diaphragm 5. When the diaphragm 5 is subjected to pressure, this uniform support can effectively disperse the pressure and avoid local stress concentration, thereby enhancing the overall strength of the diaphragm 5, making it less likely to undergo local deformation when under pressure, greatly improving the accuracy of pressure measurement. For example, when measuring pressure in a high-pressure environment, the diaphragm 5 is subjected to uniform force at all locations and will not be deformed due to excessive local pressure, ensuring that the sensor output signal accurately corresponds to the actual pressure.

[0023] The phase change material filled in the chip 602 undergoes a solid-liquid phase change when the temperature changes. When the temperature rises, the phase change material changes from solid to liquid and absorbs heat; when the temperature drops, it changes from liquid to solid and releases heat. This phase change process plays a role in buffering temperature changes, helping the shape memory polymer sheet 601 to more accurately compensate for the stress changes between the diaphragm 5 and the sensitive element caused by temperature; for example, when the temperature suddenly rises, the phase change material absorbs heat, slowing down the temperature rise rate of the shape memory polymer sheet 601 and the diaphragm 5, so that the shape memory polymer sheet 601 has more time to make shape adjustments, thereby better compensating for the additional stress on the sensitive element caused by the thermal expansion of the diaphragm 5, and further improving the temperature compensation effect.

[0024] Working principle: When the temperature changes, the expansion or contraction degree of the diaphragm 5 is different from that of the sensitive element, which leads to additional stress at their connection interface, which may cause the sensitive element to drift or even damage the signal. The thin sheet 601 attached to the surface of the diaphragm 5 changes its shape with temperature and can offset this additional stress to a certain extent. For example, in a high temperature environment, the diaphragm 5 expands thermally, generating outward tensile stress on the sensitive element. At this time, the thin sheet 601 also expands due to the temperature increase. Through the pre-designed expansion direction and amplitude, a certain force is applied in the opposite direction, thereby reducing the tensile stress on the sensitive element and achieving stress compensation.

[0025] Based on the deformation of the shape memory polymer sheet 601 when the temperature changes, a pressure self-regulating conical protective sleeve structure is designed to match it. When the shape memory polymer sheet 601 is deformed due to temperature changes, it will promote the flow of air around the diaphragm 5.

[0026] A protective jacket 7 is installed on the side of the chuck 4 away from the pressure sensor body 1. The protective jacket 7 is made of high-strength, weather-resistant polyurethane material. The protective jacket 7 is a hollow conical structure. The fixed end of the protective jacket 7 and the chuck 4 is a small-diameter end. The other side of the protective jacket 7 is sealed and is equipped with multiple gas channels 9. Multiple air pressure regulating structures 8 are installed on the protective jacket 7.

[0027] The multiple air pressure regulating structures 8 are distributed in an array, and the multiple air pressure regulating structures 8 are proportionally reduced from the large end to the small end. The air pressure regulating structure 8 includes a compensation port 811 opened on the side wall of the protective jacket 7, and a deformable capsule 812 is installed inside the compensation port 811. The deformable capsule 812 is a hollow semi-elliptical shape and is made of a highly elastic material. A through opening is opened in the center of one side of the deformable capsule 812, and a plurality of clamping angles 813 are installed on the inner periphery of the through opening.

[0028] Working principle: When the temperature rises, the shape memory polymer sheet 601 expands due to the heat, occupying more space, causing the air around the diaphragm 5 to be squeezed, and the direction and speed of the air flow change. This change is transmitted to the air pressure inside the protective jacket 7. When an air pressure difference appears inside the protective jacket 7, the semi-elliptical deformation capsule 812 can quickly change its shape according to the size of the air pressure difference. For example, when the internal air pressure is higher than the external air pressure, the air pressure difference will cause the deformation capsule 812 to expand and deform outward. Under the action of the air pressure difference, when the air pressure difference is large, the deformation capsule 812 deforms greatly, and multiple clamping corners 813 open a larger gap to quickly balance the air pressure; when the air pressure difference is small, the deformation capsule 812 deforms slightly, finely adjusts the gas flow rate, and maintains stable air pressure.

[0029] In order to remove impurities in the filter medium, the impurities are prevented from affecting the diaphragm 5 .

[0030] A filter structure 10 is provided on the gas channel 9, and the filter structure 10 includes a filter sleeve 101. The filter sleeve 101 is conical in shape, and a plurality of impurity passing grooves 102 and impurity discharge grooves 103 are respectively provided on the inner and outer sides of the filter sleeve 101. A miscellaneous cone head 104 is installed at the input end of the filter sleeve 101, and a miscellaneous receiving warped ring plate 105 is installed along the inner bottom side of the impurity passing groove 102. The impurity receiving warped ring plate 105 is in the form of a ring body, and the impurity receiving warped ring plate 105 has a warped cross-section with increasing height from the outside to the center and a curvature, and a plurality of medium passages are provided on the impurity receiving warped ring plate 105.

[0031] Working principle: When the medium is input through the gas channel 9, the medium will impact the impurity blocking cone head 104, and the impurities in the medium will be dispersed to the periphery through the conical structure. The scattered impurities will pass through multiple impurity receiving warped ring plates 105, and the impurities will be gradually blocked by the multiple impurity receiving warped ring plates 105. Combined with the raised slope design, larger impurities can be guided to the area of ​​the impurity passing groove 102, thereby realizing the centralized collection of impurities.

[0032] In order to discharge impurities and avoid accumulation of impurities and blockage; A debris removal component 11 is provided between the debris removal groove 103 and the adjacent debris passing groove 102. The debris removal component 11 includes a ball groove 111 opened on the debris filtering sleeve 101. A center ball 112 is provided at the center of the ball groove 111. The center of the center ball 112 is connected to a center shaft 113 rotatably connected to the ball groove 111. A plurality of side rings 114 are connected to the outer periphery of the center ball 112. The outer periphery of the side ring 114 is in contact with the inner wall of the ball groove 111.

[0033] Working principle: When impurities accumulate to a certain extent, the medium input can drive the side ring 114 to rotate, so that the impurities between multiple side rings 114 are rotated and transported to the impurity discharge groove 103, which can realize automatic discharge and continuous filtration.

[0034] It is worth mentioning that since the outer periphery of the side ring 114 fits with the inner wall of the ball groove 111, and the ball groove 111 has sufficient thickness, the corresponding two side rings 114 can seal the ball groove 111 during transportation, ensuring that the internal space is fixed and the flow rate will not be reduced due to the increase in space.

[0035] The problems of medium flow stability and impurity filtration are solved, but the tiny impurities and specific ions in the medium may not be completely removed. These substances may accumulate on the surface of the diaphragm 5, affecting the sensor performance.

[0036] A secondary filter layer 12 is provided on the inner periphery of the protective jacket 7. The secondary filter layer 12 is provided with a filter mesh layer 121, an activated carbon mesh layer 122 and an ion exchange membrane layer 123 from the outside to the inside. The secondary filter layer 12 is a convex pointed cone as a whole. The activated carbon mesh layer 122 uses activated carbon with nano-scale pores and has a huge specific surface area for adsorbing organic impurities and some metal ions in the medium. The ion exchange membrane layer 123 can selectively capture specific ions, such as chloride ions, sulfate ions, etc.

[0037] Working principle: The filter mesh layer 121 can filter out tiny and residual impurities, the activated carbon mesh layer 122 provides strong adsorption capacity and can effectively remove organic impurities, and the selective capture function of the ion exchange membrane layer 123 further purifies the medium and removes specific ions that may corrode the diaphragm 5 or affect the measurement. This structure ensures that the medium entering the vicinity of the diaphragm 5 is highly pure, avoids impurities and ions from damaging the performance of the diaphragm 5, extends the service life of the sensor, and improves measurement accuracy.

[0038] In order to achieve the reabsorption and removal of tiny and residual impurities and realize the circulating filtration; A plurality of spiral grooves 124 are provided on the surface of the filter mesh layer 121, which serve to guide the flow of impurities. The gas channel 9 includes an air inlet expansion head 901, and the air inlet expansion head 901 is a pipe with a gradually reduced diameter to guide the fluid to accelerate smoothly. One end of the air inlet expansion head 901 is connected to a necking end 902, and an exhaust head 903 is provided on one side of the necking end 902. The adjacent sides of the necking end 902 and the exhaust head 903 are connected to the filter sleeve 101, and a return suction pipe 904 is connected to the necking end 902. The return suction pipe 904 corresponds to the position of the spiral groove 124, and the number of the return suction pipes is the same.

[0039] Working principle: When air is taken in, the conical design of the air intake expansion mouth 901 guides the fluid to accelerate smoothly. When entering the necked end 902, the flow rate increases due to the Bernoulli principle. At the same time, the end of the return suction pipe 904 will generate suction toward the necked end 902, thereby absorbing the impurities filtered by the secondary filter layer 12 and re-entering the filtration stage, thereby realizing cyclic filtration, and the flow rate of the necked end 902 is accelerated, so that it will generate a larger flow rate when passing through the filter sleeve 101, which assists in the filtration process.

[0040] At the same time, if the intake volume is small and a pressure difference is generated, the air pressure regulating structure 8 can be used to avoid the internal and external pressure difference and ensure the accuracy of pressure detection. From the above, the above structures can be mutually correlated and coordinated.

[0041] The embodiments disclosed in the present invention are preferred embodiments, but are not limited to them. Ordinary technicians in this field can easily understand the spirit of the present invention based on the above embodiments and make different extensions and changes. As long as they do not deviate from the spirit of the present invention, they are all within the scope of protection of the present invention.

Claims

1. A pressure sensor, characterized in that: The pressure sensor comprises a main body (1), wherein one end of the main body (1) is provided with an output port (2), the other end of the main body (1) is provided with a disk fixing end (3), a chuck (4) is mounted on the end of the disk fixing end (3), a diaphragm (5) is provided in the central area of ​​the chuck (4), and a stress compensation structure (6) is provided on the side of the diaphragm (5) close to the main body (1); The stress compensation structure (6) includes a thin sheet (601), which is located between the diaphragm (5) and the sensitive element inside the pressure sensor body (1). The thin sheet (601) is made of a shape memory polymer. A honeycomb cavity group for enhancing the overall strength of the diaphragm (5) is provided between the thin sheet (601) and the diaphragm (5). A protective jacket (7) is installed on the side of the chuck (4) away from the pressure sensor body (1), and a plurality of air pressure regulating structures (8) are installed on the protective jacket (7).

2. A pressure sensor according to claim 1, characterized in that: The honeycomb cavity group is composed of a plurality of closely arranged chips (602), the chips (602) are in the shape of a regular hexagon, the chips (602) are made of a polymer material with a low thermal expansion coefficient, and the inside of the chips (602) is hollow and filled with a phase change material.

3. The pressure sensor according to claim 1, wherein: The protective jacket (7) is a hollow conical structure, the fixed end of the protective jacket (7) and the chuck (4) is a small-diameter end, and the other side of the protective jacket (7) is sealed and equipped with a plurality of gas channels (9).

4. A pressure sensor according to claim 3, characterized in that: The air pressure regulating structure (8) includes a compensation port (811) provided on the side wall of the protective jacket (7), a deformable capsule (812) being installed inside the compensation port (811), the deformable capsule (812) being hollow and semi-elliptical, the deformable capsule (812) being made of a highly elastic material, a through opening being provided at the center of one side of the deformable capsule (812), and a plurality of clamping angles (813) being installed on the inner periphery of the through opening.

5. A pressure sensor according to claim 4, characterized in that: The plurality of air pressure regulating structures (8) are distributed in an array, and the plurality of air pressure regulating structures (8) are proportionally reduced from the large end to the small end.

6. A pressure sensor according to claim 5, characterized in that: The gas passage (9) is provided with a filter structure (10), the filter structure (10) comprising a filter sleeve (101), the filter sleeve (101) being conical in shape, with a plurality of impurity passing grooves (102) and impurity discharging grooves (103) respectively provided on the inner and outer sides of the filter sleeve (101), an impurity blocking cone head (104) being installed at the input end of the filter sleeve (101), and an impurity receiving warping ring plate (105) being installed along the inner bottom side of the impurity passing groove (102).

7. A pressure sensor according to claim 6, characterized in that: The connecting warping ring plate (105) is in the form of a ring body, and the connecting warping ring plate (105) has a warping cross-section with increasing height from the outside to the center and having an arc, and a plurality of medium passage openings are provided on the connecting warping ring plate (105).

8. The pressure sensor according to claim 7, characterized in that: A debris removal member (11) is provided between the debris removal groove (103) and the adjacent debris passing groove (102). The debris removal member (111) comprises a ball groove (111) provided on the debris filtering sleeve (101). A center ball (112) is provided at the center of the ball groove (111). The center of the center ball (112) is connected to a center shaft (113) rotatably connected to the ball groove (111). A plurality of side rings (114) are connected to the outer periphery of the center ball (112). The outer periphery of the side rings (114) is in contact with the inner wall of the ball groove (111).

9. The pressure sensor according to claim 8, characterized in that: A secondary filter layer (12) is provided on the inner periphery of the protective outer jacket (7), and the secondary filter layer (12) is provided with a filter mesh layer (121), an activated carbon mesh layer (122), and an ion exchange membrane layer (123) in sequence from the outside to the inside. The secondary filter layer (12) is in the shape of a protruding pointed cone as a whole, and a plurality of spiral grooves (124) are provided on the surface of the filter mesh layer (121).

10. The pressure sensor according to claim 9, characterized in that: The gas channel (9) comprises an air inlet expansion end (901), one end of the air inlet expansion end (901) is connected to a necking end (902), one side of the necking end (902) is provided with an exhaust head (903), the adjacent sides of the necking end (902) and the exhaust head (903) are connected to a filter sleeve (101), the necking end (902) is connected to a return suction pipe (904), and the position of the return suction pipe (904) corresponds to that of the spiral groove (124).

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