Pressure sensor

Abstract

A pressure sensor comprises a shell which comprises a metal pressure interface fixed at the lower end of a cylindrical shell; a pressure introduction channel is arranged on the pressure interface; a pressure sensitive element; the supporting seat comprises a main body part and a fixed part which is fixed at the lower end of the main body part and is fixed to the pressure interface; a first pressing edge for pressing the lower end of the electrical connector to the main body part is formed at the upper end of the cylindrical shell; a first abdicating hole surrounding at least one part of the pressure sensitive element is formed in the main body part; the upper side surface of the first substrate is provided with a first signal processing circuit; a second signal processing circuit is arranged on the upper side surface of the second substrate; the compressed conductive coil spring is held in a first holding hole formed in the main body part, the lower end of the compressed conductive coil spring is in electric contact with the second signal processing circuit, and the upper end of the compressed conductive coil spring is in electric contact with the second electric contact part; and the terminal is arranged on the electrical connector. The pressure sensor is high in space utilization rate and convenient to assemble.

Description

Technical Field

[0001] This application relates to the technical field of sensors, and particularly to a pressure sensor. Background Art

[0002] In the ESC system (Electronic Stability Control) of an automobile, a pressure sensor is required to measure the pressure of the braking medium. It is usually installed on a hydraulic module with limited installation space, so it is required to have a small size, especially the lateral size. Usually, the circuit board is horizontally arranged, so the area where electronic components can be installed is small, and thus multiple circuit boards arranged vertically or horizontally need to be used. No matter which arrangement method is used, the electrical connection between these components and terminals is usually inconvenient and costly. For example, when the circuit board is arranged vertically, the wire bonding plane between it and the piezoresistive element will be perpendicular to each other, which is extremely inconvenient both in terms of equipment and control; when multiple circuit boards are arranged vertically, the fixation and electrical connection between these circuit boards also increase the cost and process complexity.

[0003] On the other hand, this kind of pressure sensor usually uses a metal elastic diaphragm as the pressure deformation body. A Wheatstone bridge composed of thick film resistors or silicon strain gauges and other resistors is attached to the surface of the side of the metal elastic diaphragm far from the pressure medium to be measured, so as to convert the strain of the metal elastic diaphragm into an electrical signal. These thick film resistors or silicon strain gauges need to be connected to the circuit board through leads. These leads and resistors are preferably protected by being covered with gel. Therefore, a frame that can accommodate gel is usually fixed on the side of the circuit board far from the metal elastic diaphragm. Summary of the Invention

[0004] In view of the deficiencies of the prior art, this application provides a pressure sensor to solve at least one aspect of the above-mentioned defects.

[0005] To achieve the above object, this application provides the following technical solution: A pressure sensor, which includes:

[0006] A housing, including a metal cylindrical shell extending longitudinally, a metal pressure interface fixed to the lower end of the cylindrical shell, and an electrical connector whose lower end extends into the cylindrical shell; a pressure introduction channel is provided on the pressure interface;

[0007] A pressure-sensitive element fixed to the inner end of the pressure introduction channel;

[0008] The support base includes a main body portion and a fixing portion fixed to the lower end of the main body portion and fixed to the pressure interface; the upper end of the cylindrical shell forms a first bead for pressing the lower end of the electrical connector against the main body portion; a first relief hole surrounding at least a part of the pressure sensitive element is provided on the main body portion;

[0009] A first substrate fixed to the upper surface of the upper end of the main body portion, the lower surface of which abuts against the pressure sensitive element with a gap therebetween, and a first signal processing circuit electrically connected to the pressure sensitive element through a lead is provided on the upper surface thereof, and a via hole allowing the lead to pass through up and down is provided thereon;

[0010] A second substrate provided on the radially inner side of the fixing portion and allowing the pressure sensitive element to pass through, and a second signal processing circuit is provided on the upper surface thereof;

[0011] A compressed conductive helical spring held in a first holding hole provided on the main body portion, the lower end of which is in electrical contact with the second signal processing circuit, and the upper end of which is in electrical contact with a first electrical contact portion provided on the lower surface of the substrate and electrically connected to the first signal processing circuit;

[0012] And a terminal provided on the electrical connector, which is electrically connected to the first substrate.

[0013] Preferably, it further includes a pressing seat fixed to the first substrate; the terminal is a spring terminal; a first holding hole for holding the lower part of the spring terminal is provided on the pressing seat; a third holding hole for holding the upper part of the spring terminal is provided in the electrical connector.

[0014] Preferably, the pressing seat includes a pressing seat main body forming the first holding hole and a first surrounding wall formed by the edge of the pressing seat main body extending downward and bonded to the edge of the upper surface of the first substrate.

[0015] Preferably, the pressing seat includes a pressing seat main body forming the first holding hole and a first surrounding wall formed by the edge of the pressing seat main body extending downward and abutting against the edge of the upper surface of the first substrate; the support base further includes a pressing portion molded at the lower end in the main body portion, and the upper end of the pressing portion is bent inward to form a second bead for pressing the pressing seat downward.

[0016] Preferably, the pressing seat includes a pressing seat body forming the first holding hole, a first surrounding wall formed by downward extension of the edge of the pressing seat body and abutting against the edge of the upper side surface of the first substrate, and a second surrounding wall formed by downward extension of the pressing seat body; the second surrounding wall abuts against or contacts the upper side surface of the first substrate, and a cavity surrounding the upper end of the via hole is formed between the second surrounding wall and the first substrate; a cavity is formed by the first surrounding wall, the second surrounding wall and the first substrate, and the first signal processing circuit includes a second electrical contact portion located in the cavity and in electrical contact with the lower end of the spring terminal.

[0017] Preferably, the cavity is filled with a gel covering the lead wires.

[0018] Preferably, a pressure sensing circuit electrically connected to the first signal processing circuit through the lead wires is disposed on a side surface of the pressure sensitive element away from the pressure introduction channel, and the gel partially fills the gap to cover the pressure sensing circuit.

[0019] Preferably, the lower end of the second surrounding wall elastically abuts against the first substrate.

[0020] Preferably, the pressing seat further includes at least one thin shell-shaped connecting portion with inner and outer radial edges respectively connected to the upper end of the second surrounding wall and the pressing seat body.

[0021] Preferably, the fixing portion includes a plurality of circumferentially spaced portions made of a metal material, and the fixing portion protrudes inward to form an anti-detachment portion for preventing the second substrate from slipping out downward.

[0022] The above pressure sensor, by providing two circuit-arrangeable substrates arranged up and down, and the lower substrate utilizes the space around the connecting flange, while increasing the layout area of electronic components, saves the space inside the housing; at the same time, it can enable the circuits on these two substrates to form a convenient electrical connection through the conductive spiral spring. Description of the Drawings

[0023] Figure 1 It is a schematic structural diagram of the pressure sensor of the first embodiment;

[0024] Figure 2 It is a schematic structural diagram of the pressure sensor of the second embodiment;

[0025] Figure 3 It is a schematic structural diagram of the pressure sensor of the third embodiment;

[0026] Description of reference numerals: 100, pressure introduction channel; 111, support disk; 11a, groove; 11, connecting flange; 1a, stepped surface; 1b, stepped surface; 1c, flange portion; 1d, upper end surface; 1f, lower end surface; 1, pressure interface; 200, pressure sensing circuit; 201, gap; 20, metal elastic diaphragm; 21, support wall; 22, enlarged portion; 2, pressure sensitive element; 311, bead; 31, pressing portion; 321, anti - detachment portion; 32, fixing portion; 33a, relief hole; 33b, holding hole; 33, main body portion; 3, support base; 400, gel; 411, electrical contact portion; 412, electrical contact portion; 41a, via hole; 41, substrate; 42a, relief hole; 42, substrate; 431, electronic component; 43, signal processing circuit; 44, electrical connector; 451, electrical contact portion; 45, signal processing circuit; 4, electronic module assembly; 501, waterproof and breathable membrane; 511, extension portion; 51a, holding hole; 51, pressing seat main body; 52, surrounding wall; 531, connecting portion; 53, surrounding wall; 5a, cavity; 5b, cavity; 5c, stepped surface; 5d, hole; 5, pressing seat; 61, bead; 6, cylindrical shell; 71, support flange; 7a, stepped surface; 7b, holding hole; 7, electrical connector; 8, spring terminal; 91, sealing ring; 92, sealing ring. Detailed implementation manners

[0027] The technical solutions of the present application will be clearly and completely described below with reference to the accompanying drawings. The following embodiments are exemplary and are only used to explain the present application, and cannot be construed as a limitation of the present application. In the following description, the same reference numerals are used to represent the same or equivalent elements, and repeated descriptions are omitted.

[0028] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "inner", "outer", "left", "right", etc. is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of the present application is usually placed during use, or the orientation or positional relationship commonly understood by those skilled in the art. It is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation of the present application. In addition, the prefixes "first", "second", "third", etc. are only used for the purpose of distinguishing the objects to be modified, and cannot be construed as indicating or implying relative importance.

[0029] In addition, the terms "mounted", "connected", and "coupled" 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 an indirect connection through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0030] It should be further understood that the term "and / or" used in the specification and corresponding claims of this application refers to any combination of one or more of the listed items and all possible combinations.

[0031] As Figure 1 shown. The pressure sensor of the first embodiment includes a housing composed of a pressure interface 1, a barrel housing 6, and an electrical connector 7. Among them, both the barrel housing 6 and the pressure interface 1 are made of metal materials. A part of the electrical connector 7 extends downward into the barrel housing 6. Among them, the barrel housing 6 extends longitudinally (i.e., the up-and-down direction in the figure), and its lower end can be welded to a stepped surface 1a formed on the pressure interface 1, and its upper end is bent inward to form a crimping edge 61 to press downward on a stepped surface 7a formed on the electrical connector 7. Preferably, a sealing ring 92 can be provided between the crimping edge 61 and the stepped surface 7a, and / or a sealant is applied between the crimping edge 61 and the outer wall of the electrical connector 7.

[0032] A pressure introduction channel 100 is formed in the pressure interface 1. The inner end of the pressure introduction channel 100 is hermetically coupled to a pressure sensitive element 2. The pressure sensitive element 2 generates a corresponding electrical signal in response to the pressure of the medium to be measured in the pressure introduction channel 100. The pressure sensor further includes an electronic module assembly 4 disposed inside the housing to process the above electrical signal. Terminals electrically connected to the electronic module assembly 4 are provided on the electrical connector 7.

[0033] The electronic module assembly 4 may include a support base 3 fixed inside the housing. The upper end of the support base 3 supports a part of the electrical connector 7 extending into the barrel housing 6, and its lower end is fixed to a stepped surface 1b formed on the pressure interface 1. For example, the support base 3 includes a main body portion 33 and a metal fixing portion 32 molded at the upper end inside the support base 3. The fixing portion 32 can be in the shape of a thin shell, which can extend continuously in the circumferential direction to form a complete circle, or be divided into a plurality of parts arranged at intervals in the circumferential direction. When the fixing portion 32 forms a complete circle, its lower end can be welded to the stepped surface 1b; when the fixing portion 32 is divided into a plurality of parts arranged at intervals in the circumferential direction, the fixing portion 32 can be snapped onto the outer wall of a flange portion 1c formed by the corresponding upward protrusion on the inner side of the stepped surface 1b.

[0034] Exemplarily, the pressure-sensitive element 2 may include a metal elastic diaphragm 20 extending laterally on the upper side surface. The peripheral edge thereof may extend downward to form a surrounding support wall 21. The lower end of the support wall 21 may be sealingly connected to the inner end of the pressure introduction channel 100. For example, the peripheral edge of the inner end of the pressure introduction channel 100 may extend upward from the upper end surface 1d of the pressure interface 1 to form a connecting flange 11. The outer wall of the connecting flange 11 may extend outward to form a surrounding support disk 111. The lower end of the support wall 21 is supported and welded to the upper side surface of the support disk 111. Among them, the support disk 111 is preferably arranged at the longitudinal middle of the connecting flange 11, so that there is a surrounding groove 11a formed by inward concavity in the radial direction between the support disk 111 and the root of the connecting flange 11 to isolate the interference of the stress during the installation of the pressure interface 1 to the metal elastic diaphragm 20. A pressure sensing circuit 200 composed of thick film resistors, semiconductor strain gauges or other types of strain resistors is insulatingly arranged on the upper side surface of the metal elastic diaphragm 20. A relief hole 33a is arranged in the middle of the main body portion 33 to accommodate at least a part of the pressure-sensitive element 2.

[0035] In some other embodiments, the pressure-sensitive element 2 may also use an elastic diaphragm made of ceramic or other suitable materials instead of the metal elastic diaphragm. A pressure sensing circuit 200 composed of thick film resistors, semiconductor strain gauges or other types of strain resistors is insulatingly arranged on the upper side surface of the elastic diaphragm. These elastic diaphragms can be fixedly sealed to the inner end of the pressure introduction channel 100 by means of pressure sealing or adhesive sealing.

[0036] The electronic module assembly 4 may include a substrate 41 and a substrate 42 which are arranged at intervals up and down and extend laterally. The substrate 42 is arranged on the radial inner side of the fixing portion 32. A signal processing circuit 43 is arranged on the upper side surface of the substrate 41, and a signal processing circuit 45 is arranged on the upper side surface of the substrate 42. The signal processing circuit 43 and the signal processing circuit 45 are electrically connected through an electrical connecting member 44 arranged on the support seat 3. For example, several electrical contact portions 412 electrically connected to the substrate 41 are arranged on the lower side surface of the substrate 41. The signal processing circuit 45 includes electrical contact portions 451 corresponding to the electrical contact portions 412. The electrical connecting member 44 is a longitudinally arranged compressed conductive helical spring. The upper and lower ends of the conductive helical spring are respectively in electrical contact with the corresponding electrical contact portions 412 and electrical contact portions 451, so as to form an electrical connection between the signal processing circuit 43 and the signal processing circuit 45. Among them, the electrical contact portions 412 can be electrically connected through metallized vias passing through both sides of the substrate 41. Preferably, a holding hole 33b for holding the conductive helical spring and communicating the upper and lower sides of the main body portion 33 is arranged on the main body portion 33.

[0037] Among them, the above-mentioned terminal is a spring terminal 8, which is preferably a stepped spring terminal, that is, it includes at least an upper section, a lower section, and a transition section connecting the upper section and the lower section, and the outer diameter of the upper section is smaller than that of the lower section. The signal processing circuit 43 also includes several electrical contact parts 411, and the electrical contact parts 411 form electrical contact with the lower end of the provided spring terminal 8. The lower part of the spring terminal 8 is held in a longitudinal holding hole 51a formed in the pressing seat body 51, and the upper part of the spring terminal 8 is held in a longitudinal holding hole 7b formed in the electrical connector 7. The upper end of the spring terminal 8 protrudes upward from the holding hole 7b to make electrical connection with an external device. The holding hole 7b is preferably a stepped hole, and the transition section is preferably also tightly coiled so as to apply a certain pressure downward on the transition section through the pressing surface of the stepped hole. Among them, the lower section at least includes a sparsely coiled elastic part, and the upper section preferably includes a tightly coiled rigid part to facilitate plugging with an external device.

[0038] In this application, two laterally extending substrates are provided as the base of the circuit, ensuring the area for mounting electronic components under the premise of relatively low lateral dimensions.

[0039] Among them, there is a gap 201 between the lower side surface of the substrate 41 and the side surface (i.e., the upper side surface) of the metal elastic diaphragm 20 away from the pressure introduction channel 100. The height of the gap 201 is preferably as small as possible on the premise of allowing a predetermined upward deformation amount of the metal elastic diaphragm 20, such as 1.5 mm to 3 mm. A through hole 41a may be provided in the middle of the substrate 41, and the pressure sensing circuit 200 forms an electrical connection between the signal processing circuit 43 on the upper side surface of the substrate 41 and the pressure sensing circuit 200 on the upper side surface of the metal elastic diaphragm 20 through a plurality of leads (not marked) passing through the through hole 41a. The substrate 41 can be fixed to the support base 3 in a suitable manner. For example, the lower side surface of the substrate 41 can be bonded to the upper end of the main body portion 33. To leave more available area on the substrate 41, it is preferably that the edge of the lower side surface of the substrate 41 is bonded to the upper end of the main body portion 33 to form a continuous annular plane or a discontinuous annular plane.

[0040] In this embodiment, the support base 3 includes a main body portion 33 and a generally vertically extending pressing portion 31 made of metal for pressing and fixing the substrate 41 downward. The pressing portion 31 can be in the shape of a thin shell and can surround the substrate 41 in the circumferential direction. Its lower end can be molded within the main body portion 33. The substrate 41 is disposed radially inside the pressing portion 31. The upper end of the pressing portion 31 is bent inward to form a pressing edge 311, and the pressing edge 311 is pressed downward against a pressing seat 5 through a sealing ring 91 disposed between the pressing edge 311 and the stepped surface 5c. The pressing seat 5 presses the substrate 41 downward against the main body portion 33. Similarly, the pressing portion 31 can also extend continuously in the circumferential direction to form a complete circle or be divided into a plurality of parts spaced apart in the circumferential direction. Among them, the lower end edge of the electrical connector 7 extends downward to form a supporting flange 71 that extends into the inner part of the cylindrical shell 6 and is supported by the main body portion 33, and the pressing portion 31 is disposed outside the pressing seat 5 and inside the supporting flange 71. Both the pressing seat 5 and the main body portion 33 are made of insulating materials, and the main body portion 33 is made of plastic.

[0041] Among them, the pressing seat 5 can include a pressing seat main body 51, and the outer edge of the pressing seat main body 51 extends downward to form a surrounding wall 52 that abuts against the upper side surface of the substrate 41. An upward stepped surface 5c is also formed on the pressing seat main body 51, and the pressing edge 311 is pressed downward against the stepped surface 5c. The lower end of the surrounding wall 52 can abut against the upper side surface of the substrate 41, preferably against the edge of the upper side surface of the substrate 41. In this way, a cavity 5a is formed between the pressing seat 5 and the upper side surface of the substrate 41, and some electronic components 431 that make up the signal processing circuit 43 can be disposed in the cavity 5a. The above-mentioned electrical contact portion 411 is disposed in the cavity 5a. In some other solutions, additionally or alternatively, the lower end of the surrounding wall 52 can also be fixed to the support base 3 by bonding.

[0042] In particular, the pressing seat body 51 may further extend downward to form a surrounding wall 53, and the surrounding wall 53 abuts or is close to the upper surface of the substrate 41 to form a cavity 5b surrounding the upper end of the via hole 41a with the substrate 41. The above-mentioned cavity 5a is formed by the surrounding wall 52, the surrounding wall 53 and the upper surface of the substrate 41. The cavity 5b communicates with the upper end surface of the pressing seat 5 through a hole 5d provided on the pressing seat body 51. The cavity 5b and the via hole 41a may be filled with a gel 400 covering the above-mentioned leads. The gel 400 may also partially overflow downward into the gap 201 to cover the lower part of the above-mentioned leads (the gel in the gap 201 can be first applied on the metal elastic diaphragm 20 to cover the lower part of the leads and then wait for it to cure for a period of time). At this time, the pressing seat 5 can act as a surrounding frame in the prior art to hold the gel 400. Preferably, a waterproof and breathable film 501 may be bonded to the upper end surface of the hole 5d. While preventing water vapor from entering the cavity 5b, a gap (not marked) is left between the electrical connector 7 and the pressing seat 5, and the hole 7b is kept communicating with the environment to introduce an environmental reference pressure on the upper surface of the metal elastic diaphragm 20, so as to measure the relative pressure of the pressure medium to be measured relative to the environment, that is, the gauge pressure.

[0043] Wherein, the edge of the metal elastic diaphragm 20 may extend radially outward relative to the support wall 21 to form an enlarged portion 22, thereby increasing the rigidity of the edge portion of the metal elastic diaphragm 20. The lower surface of the substrate 42 may be bonded to the upper end surface 1d of the pressure interface 1. At this time, at least one relief hole 42a allowing the support disk 111 to pass longitudinally is provided in the middle of the substrate 42. Thus, during assembly, the substrate 42 can be combined with the pressure interface 1 prior to the support wall 21.

[0044] Wherein, the relief hole 42a, the connecting flange 11, the support disk 111, the metal elastic diaphragm 20, and the relief hole 33a may be concentrically arranged in a circular cross-sectional shape in the transverse plane. The pressing portion 31 and the fixing portion 32 may be integrally connected.

[0045] Please refer to Figure 2。Compared with the first embodiment, in the pressure sensor of the second embodiment, the fixing portion 32 and the main body portion 33 can be integrally made of the same material. The fixing portion 32 is divided into a plurality of circumferentially spaced parts, and the fixing portion 32 is snap-fitted to the flange portion 1c. The sealing ring 91 can be omitted, so that the bead 311 can be directly pressed downward against the step surface 5c. The pressing seat 5 further includes at least one ring-shaped connecting portion 531 in the shape of a thin shell, with the radially inner and outer edges respectively connected to the upper end of the surrounding wall 53 and the pressing seat main body 51. In this way, the surrounding wall 53 and the connecting portion 531 can have relatively high longitudinal telescopic deformation ability as a whole, so that the lower end of the surrounding wall 53 elastically abuts against the upper side surface of the substrate 41, so as to avoid excessive deformation of the substrate 41 due to excessive pressure when the lower end edge of the surrounding wall 53 abuts against the upper side surface of the substrate 41. In addition, the relief hole 42a not only allows the support disk 111 to pass longitudinally, but also allows the enlarged portion 22 to pass longitudinally. Thus, after the edge portion of the upper side surface of the substrate 42 is pre-bonded to the lower side surface of the main body portion 33, it can be assembled to the pressure interface 1 together with the support seat 3.

[0046] Preferably, the radially inner edge and the radially outer edge of the connecting portion 531 are at different upper and lower heights, and the lower edge of the connecting portion 531 is connected to the pressing seat main body 51, and the upper edge of the connecting portion 531 is connected to the upper end of the surrounding wall 53, so as to further improve the longitudinal telescopic deformation ability of the surrounding wall 53 and the connecting portion 531 as a whole.

[0047] Please refer to Figure 3 。Compared with the first embodiment, in the pressure sensor of the third embodiment, the upper end edge of the holding hole 51a protrudes upward to form an extension portion 511, so as to increase the longitudinal height of the holding hole 51a to better hold the spring terminal 8. Especially when the height of the holding hole 51a is sufficient, the spring terminal 8 can be first inserted into the holding hole 51a, and the spring terminal 8 can be held in a vertical state through the holding hole 51a. In addition, the relief hole 42a not only allows the support disk 111 to pass longitudinally, but also allows the enlarged portion 22 to pass longitudinally. Thus, after the edge portion of the upper side surface of the substrate 42 is pre-fixed to the lower side surface of the main body portion 33, it can be assembled to the pressure interface 1 together with the support seat 3. Among them, an anti-detachment portion 321 protruding radially inward can be formed on the fixing portion 32 by means of pressing or the like, so as to press the substrate 42 against the lower end surface 1f of the main body portion 33 through the anti-detachment portion 321. At this time, it is preferably to configure the anti-detachment portion 321 into a plurality of circumferentially spaced parts, so that when the substrate 42 is installed on the main body portion 33, the anti-detachment portion 321 is prone to elastic deformation to allow the substrate 42 to pass over the anti-detachment portion 321.

[0048] The scope of the present disclosure is not limited by the detailed description, but is defined by the claims and their equivalents, and all variations within the scope of the claims and their equivalents are construed as being included in the present disclosure.

Claims

1. A pressure sensor, characterized in that: include: The housing comprises a metal cylindrical shell (6) extending longitudinally, a metal pressure interface (1) fixed at the lower end of the cylindrical shell (6), and an electrical connector (7) whose lower end extends into the cylindrical shell (6); a pressure introduction channel (100) is provided on the pressure interface (1); A pressure sensitive element (2) fixed to one end of the inner side of the pressure introduction channel (100); The support seat (3) comprises a main body (33), a fixing portion (32) fixed to the lower end of the main body (33) and fixed to the pressure interface (1); the upper end of the cylinder shell (6) forms a first pressing edge (61) for pressing the lower end of the electrical connector (7) to the main body (33); the main body (33) is provided with a first clearance hole (33a) surrounding at least a part of the pressure sensitive element (2); A first substrate (41) fixed to the upper end surface of the main body (33), the lower surface of which is close to the pressure sensitive element (2) and a gap (201) is left between the pressure sensitive element (2), and the upper surface of which is provided with a first signal processing circuit (43) electrically connected to the pressure sensitive element (2) through a lead, and a via hole (41a) is provided on the first substrate to allow the lead to pass up and down; A second substrate (42) having a second clearance hole (42a) disposed radially inwardly of the fixing portion (32) and allowing the pressure sensitive element (2) to pass through, wherein a second signal processing circuit (45) is disposed on an upper surface of the second substrate; a compressed conductive coil spring held in a first holding hole (33b) provided on the main body (33), the lower end of which is electrically in contact with the second signal processing circuit (45), and the upper end of which is electrically in contact with a first electrical contact portion (412) provided on the lower surface of the substrate (41) and electrically connected to the first signal processing circuit (43); and a terminal disposed on the electrical connector (7) which is electrically connected to the first substrate (41).

2. The pressure sensor according to claim 1, characterized in that: It also includes a pressure seat (5) fixed to the first substrate (41); the terminal is a spring terminal (8); the pressure seat (5) is provided with a first retaining hole (51a) for retaining the lower part of the spring terminal (8); and the electrical connector (7) is provided with a third retaining hole (7b) for retaining the upper part of the spring terminal (8).

3. The pressure sensor according to claim 2, characterized in that: The pressure seat (5) includes a pressure seat body (51) forming the first retaining hole (51a) and a first surrounding wall (52) formed by extending downward from the edge of the pressure seat body (51) and bonded to the edge of the upper surface of the first substrate (41).

4. The pressure sensor according to claim 2, characterized in that: The pressure seat (5) includes a pressure seat body (51) forming the first retaining hole (51a) and a first surrounding wall (52) formed by extending downward from the edge of the pressure seat body (51) and supporting the edge of the upper surface of the first substrate (41); the support seat (3) also includes a clamping portion (31) whose lower end is molded in the main body (33), and the upper end of the clamping portion (31) is bent inward to form a second clamping edge (311) for pressing the pressure seat (5) downward.

5. The pressure sensor according to claim 2, characterized in that: The pressure seat (5) comprises a pressure seat body (51) forming the first retaining hole (51a), a first surrounding wall (52) formed by extending downward from the edge of the pressure seat body (51) and supporting the edge of the upper surface of the first substrate (41), and a circle of second surrounding walls (52) formed by extending downward from the pressure seat body (51); the second surrounding wall (52) is close to or abuts against the upper surface of the first substrate (41) and forms a cavity (5b) surrounding the upper end of the via hole (41a) between the second surrounding wall (52) and the first substrate (41); the first surrounding wall (52), the second surrounding wall (52) and the first substrate (41) form a cavity (5a), and the first signal processing circuit (43) comprises a second electrical contact portion (411) located in the cavity (5a) and electrically contacting the lower end of the spring terminal (8).

6. The pressure sensor according to claim 5, characterized in that: The cavity (5b) is filled with a gel (400) covering the lead wire.

7. The pressure sensor according to claim 6, characterized in that: A pressure sensing circuit (200) electrically connected to the first signal processing circuit (43) via the lead is provided on a surface of one side of the pressure sensitive element (2) away from the pressure introduction channel (100), and the gel (400) partially fills the gap (201) to cover the pressure sensing circuit (200).

8. The pressure sensor according to claim 5, characterized in that: The lower end of the second surrounding wall (52) elastically abuts against the first base plate (41).

9. The pressure sensor according to claim 8, characterized in that: The pressure seat (5) further comprises at least one circle of thin shell-shaped connecting parts (531) whose radial inner and outer side edges are respectively connected to the upper end of the second surrounding wall (52) and the pressure seat body (51).

10. The pressure sensor according to claim 8, characterized in that: The fixing portion (32) comprises a plurality of parts made of metal material and arranged at intervals in the circumferential direction, and the fixing portion (32) protrudes inward to form an anti-slip portion (321) for preventing the second substrate (42) from slipping out downward.

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