Pressure detection sensor and detection method

Abstract

The present invention discloses a pressure detection sensor and a detection method. In this solution, a sealing leather cup is used to separate the detection cavity in the shell into two mutually unconnected first detection cavities and second detection cavities; the sealing leather cup is deformed based on the pressure difference between the first detection cavity and the second detection cavity; the elastic moving component arranged in the first detection cavity or / and the second detection cavity cooperates with the sealing leather cup, and when the sealing leather cup is deformed, the deformed sealing leather cup is driven to move in the corresponding detection cavity; the magnetic field element cooperates with the elastic moving component, and changes the magnetic field in the corresponding detection cavity under the drive of the elastic moving component when it moves; the induction element detects the change of the magnetic field in the first detection cavity or / and the second detection cavity. This solution is a corresponding mechanical structure as a whole, and has a compact and simple structure, low cost, high reliability, can withstand various impact pressures, and is suitable for various harsh and complex application environments.

Description

Technical Field

[0001] The present invention relates to sensor technology, in particular to pressure detection sensor technology. Background Art

[0002] In existing pressure detection sensing technologies, gas and liquid pressures are mainly detected using MEMS sensors.

[0003] MEMS pressure sensors have a fast response speed, but a long development cycle and difficult process, resulting in high costs and a small product range. Even if users pay a high cost, it is not easy to choose a suitable product. In particular, in order to maintain the detection accuracy of MEMS sensors, some key parts need to use high-hardness adhesives, and these adhesives are brittle and are easily damaged by the shock wave of the liquid when detecting liquid pressure.

[0004] It can be seen that providing a pressure sensor that is suitable for various complex detection environments, has a simple structure and stable and reliable performance is an issue that needs to be urgently addressed in the field. Summary of the invention

[0005] In view of the problems existing in the existing pressure detection sensing technology, a pressure detection sensing solution with simple structure and stable and reliable performance is needed.

[0006] To this end, the purpose of the present invention is to provide a pressure detection sensor, which has a compact and simple structure, high reliability, and can be applied to various complex detection environments, thereby effectively overcoming the problems existing in the prior art; accordingly, the present invention further provides a pressure detection method to achieve reliable pressure detection.

[0007] In order to achieve the above-mentioned object, the pressure detection sensor provided by the present invention includes a housing, a sealing leather cup, at least one elastic moving component, at least one sensing element and at least one magnetic field element;

[0008] A corresponding detection cavity is formed in the shell;

[0009] The sealing leather cup is sealingly arranged in the detection cavity of the shell, and separates the detection cavity in the shell into two mutually unconnected first detection cavities and second detection cavities; the sealing leather cup can be deformed based on the pressure difference between the first detection cavity and the second detection cavity;

[0010] An elastic moving component is arranged in the first detection cavity or / and the second detection cavity, and the elastic moving component cooperates with the sealing leather cup, and when the sealing leather cup is deformed, the deformed sealing leather cup drives the elastic moving component to move in the corresponding detection cavity;

[0011] The magnetic field element forms a magnetic field in the first detection cavity and / or the second detection cavity, and the magnetic field element cooperates with the elastic moving component in the detection cavity, and changes the magnetic field in the corresponding detection cavity when the elastic moving component moves;

[0012] The sensing element detects changes in the magnetic field in the first detection cavity and / or the second detection cavity.

[0013] Furthermore, the shell includes a first shell and a second shell, a first detection cavity is formed in the first shell, a second detection cavity is formed in the second shell, the first shell and the second shell are connected and combined to form a shell, so that the first detection cavity in the first shell and the second detection cavity in the second shell correspond to each other; the sealing leather cup is arranged between the first shell and the second shell, separating the first detection cavity in the first shell from the second detection cavity in the second shell.

[0014] Furthermore, the elastic moving component includes a push rod and a spring. The push rod is placed in the corresponding detection cavity of the shell through the spring. The top end of the push rod cooperates with the sealing leather cup and can be driven when the sealing leather cup is deformed and move along the deformation direction of the sealing leather cup. The push rod will drive the spring to deform during the movement.

[0015] Furthermore, the magnetic field element is a magnet.

[0016] Furthermore, the magnet is arranged on the elastic moving component.

[0017] Furthermore, the magnetization direction of the magnet is consistent with the movement direction of the elastic moving component.

[0018] Furthermore, the moving distance of the magnet along with the elastic moving component is less than or equal to the length of the magnet.

[0019] Furthermore, a corresponding thrust stop is provided in the housing to cooperate with the elastic moving component.

[0020] Furthermore, the induction element is installed on the outside or outer end of the magnetic field element.

[0021] Furthermore, when the sensor is installed on the outside of the magnetic field element, the distance between the surface of the sensor element and the surface of the magnetic field element is 0.5mm to 8mm; when the sensor is installed on the outer end of the magnetic field element, the distance between the surface of the sensor element and the surface of the magnetic field element is 1.5mm to 9mm.

[0022] In order to achieve the above object, the present invention provides a pressure detection method, which comprises:

[0023] The elastic deformation element senses the pressure and converts the pressure difference into corresponding mechanical displacement;

[0024] The induced magnetic field changes due to mechanical displacement;

[0025] Detect changes in the magnetic field and calculate the pressure or pressure difference based on the changes in the magnetic field.

[0026] The pressure detection sensor solution provided by the present invention is a corresponding mechanical structure as a whole, and has a compact and simple structure, low cost, high reliability, and can withstand various impact pressures, and is suitable for various harsh and complex application environments.

[0027] Furthermore, when the pressure detection sensor solution provided by the present invention is used, the detection range can be changed by simply adjusting the spring stiffness, and it has a wide range of applications and good market prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0029] Figure 1 An exploded diagram of the pressure detection sensor provided in Example 1 of the present invention;

[0030] Figure 2 A cross-sectional view of the pressure sensor body provided in Example 1 of the present invention;

[0031] Figure 3 This is a schematic diagram of the structure of the sealing cup in Example 1 of the present invention;

[0032] Figure 4 This is a schematic diagram of the magnetic field distribution of the magnet in Example 1 of the present invention;

[0033] Figure 5 This is a schematic diagram of the overvoltage protection structure in Example 1 of the present invention;

[0034] Figure 6 This is a schematic diagram of the structure of the pressure-free differentiation solution provided in Example 2 of the present invention. DETAILED DESCRIPTION

[0035] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below with reference to specific diagrams.

[0036] In order to avoid various drawbacks of existing MEMS solutions, the solution of the present invention innovatively adopts elastic deformation elements to sense pressure and convert the pressure difference into corresponding mechanical displacement; then the mechanical displacement drives the induced magnetic field change; finally, the change of the magnetic field is detected, and the pressure or pressure difference is calculated according to the change of the magnetic field, thereby realizing pressure detection.

[0037] To this end, the solution of the present invention is mainly composed of a housing, a sealing leather cup, at least one elastic moving component, at least one inductive element and at least one magnetic field element that cooperate with each other.

[0038] A corresponding detection cavity is formed in the shell; and a sealing leather cup is sealed in the detection cavity of the shell to separate the detection cavity in the shell into two mutually unconnected first detection cavities and second detection cavities; at the same time, the sealing leather cup can be deformed based on the pressure difference between the first detection cavity and the second detection cavity.

[0039] In conjunction with this, the present scheme has an elastic moving component arranged in the first detection cavity and / or the second detection cavity. The elastic moving component cooperates with the sealing leather cup and can be driven by the deformed sealing leather cup to move in the corresponding detection cavity along the direction of the deformation of the sealing leather cup when the sealing leather cup is deformed, thereby converting the pressure difference or pressure into corresponding mechanical displacement.

[0040] Furthermore, the present solution forms a corresponding magnetic field in the first detection cavity or / and the second detection cavity through a magnetic field element, and the magnetic field element cooperates with an elastic moving component in the detection cavity, and can change the magnetic field in the corresponding detection cavity when the elastic moving component is driven to move;

[0041] Furthermore, in this solution, the change of the magnetic field in the first detection cavity and / or the second detection cavity is detected by the sensing element.

[0042] The present invention thus cleverly converts the pressure difference or pressure into corresponding mechanical displacement through the cooperation of the sealing leather cup and the elastic moving component; on this basis, based on the characteristics of magnetic field change and induction, and utilizing the characteristics of the spatial distribution of the magnetic field, the pressure detection is achieved by detecting the changes in the spatial magnetic field through the sensing element.

[0043] When this solution is used in practice, the high-pressure fluid can be connected to an independent cavity (i.e., the first detection cavity or / and the second detection cavity) separated by a sealing leather cup in the shell. If the low-pressure liquid is connected to the first detection cavity, the elastic moving component in the first detection cavity cooperates with the sealing leather cup, so that the sealing leather cup will deform toward the first detection cavity under the use of the pressure difference, and then drive the elastic moving component in the first detection cavity to move in the first detection cavity, and undergo corresponding elastic deformation, thereby realizing the conversion from pressure to mechanical movement. At this time, when the elastic moving component moves in the first detection cavity, it will drive or drive the corresponding magnetic field element in the first detection cavity to move, and then change the magnetic field generated by the magnetic field element in the first detection cavity. In this way, according to the characteristics of the spatial distribution of the magnetic field of the magnetic field element in the first detection cavity, the induction element is used to detect the change of the spatial magnetic field in the first detection cavity, thereby detecting the pressure difference between the two liquids.

[0044] With respect to the above scheme, the implementation process of this scheme is further explained below through specific examples.

[0045] Example 1,

[0046] See also Figure 1 and Figure 2 , which is a composition example diagram of a pressure detection sensor formed based on the above principle.

[0047] As can be seen from the figure, the pressure detection sensor mainly includes nine parts: an upper shell (1), a sealing leather cup (2), a push rod (3), a magnet (4), a sensor (5), a wiring harness (6), a spring (7), a lower shell (8), and an end cover (9).

[0048] The upper shell (1) and the lower shell (8) are connected and matched to form the shell component of the entire pressure detection sensor. The upper shell (1) serves as the first shell of the pressure detection sensor, and a first detection cavity A is formed therein; and the lower shell (8) serves as the second shell of the pressure detection sensor, and a second detection cavity B is formed therein. At the same time, the upper shell (1) and the lower shell (8) are connected and combined by a snap-fit ​​structure, and the first detection cavity A on the upper shell (1) and the second detection cavity B on the lower shell (8) are arranged corresponding to each other (such as Figure 2 shown).

[0049] It should be noted that the specific structural form and configuration scheme of the upper shell (1) and the lower shell (8) in this example can be determined according to actual needs. Figure 1 and Figure 2 The configuration scheme shown in , other configuration schemes may also be adopted, which are not limited here. As long as the structure can be guaranteed to be stable and reliable and convenient for practical application.

[0050] Furthermore, the specific structural form and configuration scheme of the clamping structure for connecting and assembling the upper shell (1) and the lower shell (8) can be determined according to actual needs. Figure 1 and Figure 2 The configuration scheme shown in , other configuration schemes may also be adopted, which are not limited here. As long as the structure can be guaranteed to be stable and reliable and convenient for practical application.

[0051] On this basis, this example further provides a sealing leather cup (2) at the connection between the upper shell (1) and the lower shell (8). When the upper shell (1) and the lower shell (8) are connected and assembled, the sealing leather cup (2) is compressed to form a sealing structure, and at the same time seals the connecting end of the upper shell (1) and the connecting end of the lower shell (8), thereby sealing and isolating the first detection cavity A on the upper shell (1) and the second detection cavity B on the lower shell (8), respectively, thereby forming two independent cavities, a high-pressure cavity A and a low-pressure cavity B, which are not connected to each other, in the upper shell (1) and the lower shell (8); and at the same time, the two side surfaces of the sealing leather cup (2) are directly located in the high-pressure cavity A and the low-pressure cavity B, respectively, and directly sense the pressure in the high-pressure cavity A and the low-pressure cavity B.

[0052] See also Figure 3 , which is a diagram showing an example of the structure of the sealing leather cup (2) in this example. The entire structure of the sealing leather cup (2) has a bowl shape along the edge, and the outer convex part is arranged facing the high-pressure chamber A in the upper shell (1).

[0053] In order to ensure the sealing effect, the sealing leather cup (2) is made of elastic material or a composite material of elastic material and other materials.

[0054] For example, the sealing leather cup (2) is made of corresponding elastic rubber, and two sets of sealing ribs 201, 202, 203, 204 are symmetrically arranged on both sides of the edge, thereby effectively preventing leakage of the cavities A and B. The sealing ribs 201, 202, 203, 204 are respectively distributed along the circumferential direction on both sides of the edge to form corresponding convex rings.

[0055] After the upper shell and the lower shell are assembled, the compression rate of the sealing ribs along the edge of the sealing leather cup (2) is 10% to 90%, preferably 30% to 70%, such as 30%, 40%, 50%, 60% and 70%, thereby ensuring the sealing effect.

[0056] The sealing leather cup (2) thus arranged can sense the changes in the pressure in the high-pressure chamber A and the low-pressure chamber B located on both sides thereof, and can deform accordingly according to the pressure changes, that is, the deformation is driven by the pressure difference.

[0057] On this basis, this example further sets an elastic moving component composed of a push rod (3) and a spring (7) in the low-pressure chamber B of the lower shell (8), which is used to cooperate with the sealing leather cup (2), sense the deformation of the sealing leather cup (2), and move in the low-pressure chamber B of the lower shell (8) under the drive of the deformation of the sealing leather cup (2), and then convert the pressure into mechanical movement.

[0058] Specifically, a corresponding end cap is provided at the top of the push rod (3), and the structure of the end cap cooperates with the sealing leather cup (2). At the same time, a spring (7) is sleeved on the push rod (3), one end of which abuts against the end cap on the push rod (3), and the other end abuts against the step in the low-pressure chamber B of the lower shell (8), thereby forming an elastic moving component that cooperates with the sealing leather cup (2).

[0059] In the elastic moving assembly thus arranged, when the spring (7) is in a normal state, the top end of the push rod (3), i.e., the end cap, will cooperate with the sealing leather cup (2), so that when the sealing leather cup (2) is driven by the pressure difference formed between the high-pressure chamber A and the low-pressure chamber B, it will deform toward the low-pressure chamber B, thereby driving the push rod (3) to move. During the movement, the push rod (3) will compress the spring (7), thereby realizing the conversion from pressure to displacement of the push rod (3) based on Newton's third law.

[0060] Preferably, when the elastic moving component is arranged in the low-pressure chamber B, when the spring thereon is at a free length, the gap between the push rod and the sealing leather cup is preferably in the range of 0±0.5mm to ensure the detection accuracy.

[0061] In this example, a magnet (4) is used as a magnetic field element to form a corresponding magnetic field in the low-pressure chamber B. In order to allow the magnetic field formed by the magnet (4) in the low-pressure chamber B to change with the movement of the top rod (3), in this example, the magnet (4) is preferably embedded in the top rod (3) and moves synchronously with the movement of the top rod (3). At the same time, the magnetization direction of the magnet (4) is consistent with the axial direction of the top rod (3) (e.g. Figure 4 As shown), such an arrangement allows the corresponding spatial magnetic field to change regularly when the magnet moves along the magnetization direction, making it easier to detect the displacement distance of the magnet based on the spatial magnetic field transformation.

[0062] Furthermore, within the detection pressure range of the pressure sensor, the magnet movement distance is ≤ the magnet length. This setting makes the spatial magnetic field change generated by the magnet close to a linear change, which further facilitates the subsequent calculation of the displacement distance directly from the magnetic field change, reducing costs and improving efficiency.

[0063] With respect to the magnetic field formed by the magnet (4), this example uses a sensor (5) to detect changes in the magnetic field, and transmits the induction signal through a wiring harness (6).

[0064] Preferably, this embodiment uses a linear Hall element as the sensor (5) (ie, the sensing element).

[0065] The linear Hall element is preferably mounted on the outside or outer end of the magnet (4), and its position does not move with the pressure change of the detection fluid. The outside here refers to the side parallel to the moving direction, and the outer end refers to the outside of the cavity perpendicular to the moving direction.

[0066] The inventors have determined through a large number of experiments that when the sensor is installed outside the magnet, the distance between the sensor surface and the magnet surface is preferably 0.5mm to 8mm. If the distance is too close, the linear relationship of the strong magnetic field is poor and difficult to use, and the magnetic field strength of the good linear part is weak, which makes detection more difficult and affects the performance of the sensor; if the distance is too far, the magnetic field strength is weak, the detection difficulty increases, and affects the performance of the sensor.

[0067] Similarly, when the sensor is installed at the outer end of the magnet, the distance between the sensor surface and the magnet surface is preferably 1.5mm to 9mm. Through a large number of experiments, it has been determined that when the distance is too close, the gradient of the magnetic field intensity change is large, and the corresponding detection range of the detection element needs to be large enough, which will greatly increase the cost, and the magnetic field only changes linearly within a very small displacement range, which is not conducive to improving product accuracy and affects the performance of the sensor; when the distance is too far, the magnetic field intensity is weak, the detection difficulty is relatively large, and the performance of the sensor is affected.

[0068] With respect to the elastic moving component placed in the low-pressure chamber B of the lower shell (8), in this embodiment, an end cover (9) is provided at the rear end of the lower shell (8) to protect the sensor (5) fixed on the lower shell (8), and the wiring harness (6) outputs the sensor signal. The specific configuration of the end cover (9) can be determined according to actual needs and is not limited here.

[0069] On the basis of the above solution, this example further provides a corresponding thrust stop (801) on the lower shell (8), and the thrust stop (801) is used to cooperate with the push rod (3) to limit the movement stroke of the push rod (3), thereby forming an overpressure protection device for the pressure detection sensor (such as Figure 5 shown).

[0070] It should be noted that the specific structure of the thrust stop here can be determined according to actual needs and is not limited here, as long as the strength is sufficient to protect the product from being damaged during overpressure.

[0071] As an example, the thrust stop (801) in this example is arranged relative to the free end faces (301) and (302) of the push rod (3). When the sensor is at the maximum detection pressure (i.e., the cavity A is at the maximum pressure), the thrust stop is 0.5 mm to 5 mm away from the end faces (301) and (302) of the push rod, and is preferably 1 mm.

[0072] Based on the overpressure protection device with such a structure, when the fluid valve is opened, the pressure of the fluid will suddenly increase and form a shock wave. The distance between the thrust stop (801) and the top pillars (301) and (302) allows the spring (7) to continue to be compressed appropriately, effectively buffering the damage to the sensor caused by the shock wave. When the detection pressure exceeds the measurement range of the sensor, the spring (7) is further compressed, so that the displacement of the push rod (3) continues to expand until the top pillars (301) and (302) on the push rod (3) touch the thrust stop (801). After that, even if the pressure of the cavity A continues to increase, the push rod (3) will no longer move, and the spring (7) will no longer continue to be compressed, thereby preventing the spring (7) from being damaged due to overpressure or the leather cup (2) from being damaged due to being out of support.

[0073] When the pressure detection sensor thus constructed is in operation, its push rod (3) is close to the sealing leather cup (2). When the pressure in the high-pressure chamber A is greater than the pressure in the low-pressure chamber B, the sealing leather cup rapidly moves toward the low-pressure chamber under the action of the chamber pressure difference between the high-pressure chamber A and the low-pressure chamber B and squeezes the push rod (3), thereby compressing the spring (7) through the push rod (3). The movement amount of the push rod (3) is the compression amount of the spring, thereby realizing the conversion from pressure difference to displacement.

[0074] Since the magnet (4) is fixed on the push rod, the magnet (4) and the push rod move the same distance. When the stiffness of the spring (7) increases, the compression of the spring decreases under the same pressure difference, that is, the displacement of the push rod decreases; that is, when the push rod maintains the same displacement, the pressure difference between the A and B chambers increases. Similarly, when the stiffness of the spring (7) decreases, when the push rod maintains the same displacement, the pressure difference between the A and B chambers decreases. That is, by selecting springs (7) of different stiffness, the detection range of the sensor can be quickly adjusted; in this way, the detection range can be changed by simply adjusting the spring stiffness, which greatly improves the practicality of the pressure detection sensor.

[0075] See also Figure 2 and Figure 4 When the magnet is magnetized along its axial direction, different positions in the space around the magnet have different magnetic field strengths and directions. At the same time, since the magnet (4) is fixed on the top rod, when the magnet (4) top rod moves the same distance, the magnetic field strength and direction generated in the same area will change accordingly.

[0076] In this pressure detection sensor, a linear Hall sensor is placed on the side of the magnet to detect the change in magnetic field. By detecting the change in magnetic field strength, the moving distance of the magnet (4) (equivalent to the push rod (3)) can be known, thereby indirectly calculating the pressure difference between the A and B chambers, thereby realizing the pressure difference detection.

[0077] In specific applications, when fluids of different pressures are filled into two cavities A and B, the sensor detects the pressure difference between the two cavities; when fluid is only filled into one of the cavities and the other cavity is connected to the atmosphere, the sensor detects the pressure of the filled fluid. For example, when the low-pressure cavity B is connected to the atmosphere and no other fluid is connected, the pressure difference between cavities A and B is the pressure of the fluid connected to cavity A, thereby realizing the detection of fluid pressure.

[0078] Example 2

[0079] Based on the solution of Example 1, this example provides a variation solution.

[0080] See also Figure 6As shown, based on the scheme of Example 1, this example further adds a push rod (10) and a spring (11) in the high-pressure chamber A of the upper shell (1) to form a corresponding elastic moving component. The structure of the push rod (10) and the spring (11) here is the same as that of Example 1 and will not be repeated here.

[0081] On this basis, corresponding magnets (4) and sensors (5) are also arranged in the high-pressure chamber A of the upper shell (1) to cooperate with the elastic moving component composed of the top rod (10) and the spring (11). The specific construction scheme is the same as that of Example 1 and will not be repeated here.

[0082] The pressure detection sensor constructed in this way increases the pre-pressure on the spring (7) and the spring (11) after assembly, so that when the fluid is connected, the A cavity and the B cavity no longer need to distinguish between high-pressure and low-pressure cavities. The pre-pressure of the spring (7) and (11) must not be less than the displacement of the ejector rod under the maximum detection pressure.

[0083] Furthermore, the operating principle and process of the pressure detection sensor given in this example are the same as those in Example 1 and will not be elaborated here.

[0084] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A pressure detection sensor, characterized in that: It includes a housing, a sealing cup, at least one elastic moving component, at least one inductive element and at least one magnetic field element; A corresponding detection cavity is formed in the shell; the shell includes a first shell and a second shell, a first detection cavity is formed in the first shell, a second detection cavity is formed in the second shell, and the first shell and the second shell are connected and combined to form a shell, so that the first detection cavity in the first shell and the second detection cavity in the second shell correspond to each other; The sealing leather cup is sealingly arranged in the detection cavity of the shell, and divides the detection cavity in the shell into two mutually unconnected first detection cavity and second detection cavity; the sealing leather cup is arranged between the first shell and the second shell, and separates the first detection cavity in the first shell from the second detection cavity in the second shell; the sealing leather cup can be deformed based on the pressure difference between the first detection cavity and the second detection cavity, and the sealing leather cup is symmetrically provided with two groups of sealing ribs along the two sides of the edge, and the sealing ribs are respectively distributed in the circumferential direction on the two sides of the edge to form corresponding convex rings; An elastic moving component is arranged in the first detection cavity or / and the second detection cavity, and the elastic moving component cooperates with the sealing leather cup, and when the sealing leather cup is deformed, the deformed sealing leather cup drives the elastic moving component to move in the corresponding detection cavity; The magnetic field element forms a magnetic field in the first detection cavity and / or the second detection cavity, and the magnetic field element cooperates with the elastic moving component in the detection cavity, and changes the magnetic field in the corresponding detection cavity when the elastic moving component moves; The sensing element detects changes in the magnetic field in the first detection cavity and / or the second detection cavity; The elastic moving component includes a push rod and a spring. An end cap is provided on the top of the push rod. The structure of the end cap matches the sealing leather cup. The spring is sleeved on the push rod. One end of the spring abuts against the end cap on the push rod, and the other end abuts against the step in the lower shell. The push rod is placed in the corresponding detection cavity of the shell through the spring. The top end of the push rod matches the sealing leather cup and can be driven when the sealing leather cup is deformed and move along the deformation direction of the sealing leather cup. The push rod will drive the spring to deform during the movement. When the spring is at a free length, the gap between the push rod and the sealing leather cup is 0±0.5mm. The magnetic field element is a magnet, the magnet is arranged on the elastic moving component, the sensing element is installed on the outside of the magnet, and the distance between the sensor surface and the magnet surface is 0.5mm-8mm; A corresponding thrust stop is provided in the shell to cooperate with the elastic moving component to limit the moving stroke of the push rod. The thrust stop is set relative to the free end face of the push rod. When the sensor is at the maximum detection pressure, the thrust stop is 0.5mm-5mm away from the free end face of the push rod.

2. The pressure detection sensor according to claim 1, characterized in that: The magnetization direction of the magnet is consistent with the moving direction of the elastic moving component.

3. The pressure detection sensor according to claim 1, characterized in that: The moving distance of the magnet along with the elastic moving component is less than or equal to the length of the magnet.

4. The pressure detection sensor according to claim 1, characterized in that: The inductive element is mounted at the outer end of the magnetic field element.

5. The pressure detection sensor according to claim 4, characterized in that: When the inductor is mounted on the outer end of the magnetic field element, the distance between the surface of the inductor element and the surface of the magnetic field element is 1.5 mm to 9 mm.

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