Pressure sensor

Abstract

A pressure sensor includes: a pressure sensitive element having a pressure chamber, the pressure sensitive element having a longitudinally extending enclosure wall with a longitudinal proximal end closed, the front side portion of the enclosure wall forming a longitudinally extending elastic diaphragm; the elastic diaphragm generates corresponding deformation after receiving the pressure of the pressure medium to be measured in the pressure cavity on the inner side, and the deformation is converted into a corresponding electric signal through a pressure measuring circuit attached to the outer side surface of the elastic diaphragm; the supporting element comprises a main body part located on one side of the longitudinal near end of the pressure sensitive element, and the main body part is provided with a forward mounting plane; the circuit board is longitudinally arranged and extends left and right; the rear side of the circuit board is fixed to the mounting plane, a film plane provided with a processing circuit is formed on the front side of the circuit board, and the processing circuit is in backward electric contact with the pressure measuring circuit through a plurality of conductive elastic pieces. According to the pressure sensor, reliable electric connection can be formed between the circuit board and the pressure sensitive element on the premise that the supporting element does not need to be completely fixed to the pressure interface.

Description

Technical Field

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

[0002] In the hydraulic module of an automotive braking system, the lateral dimensions of the pressure sensor are limited by installation space, so its circuit board typically needs to be arranged vertically to provide sufficient area for electronic components. In this type of pressure sensor, the vertical circuit board needs to be electrically connected to the terminals, for example, by connecting it to the horizontal circuit board above via a flexible circuit board, and then electrically connecting the horizontal circuit board to the terminals, such as by vertically electrically contacting the lower end of the spring terminal to the electrical contact portion on the horizontal circuit board, as shown in CN118090016A; or additional electrical connectors are provided to connect the vertical circuit board and the spring terminal, as shown in CN118090016A. In these sensors, the supporting element of the circuit board must first be fully fixed before the measurement circuit on the pressure-sensitive element can be wire-bonded to the processing circuit, which is inherently difficult. Furthermore, the terminal button is pressed downward by the cylindrical shell to the supporting element to the pressure interface, which requires the terminal on the terminal button to be connected to the circuit board via an electrical contact spring or flexible board, which also increases costs.

[0003] The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art. Summary of the Invention

[0004] In response to the deficiencies of the prior art, the present application provides a pressure sensor, which enables a reliable electrical connection to be formed between a circuit board and a pressure-sensitive element without completely fixing the supporting element to the pressure interface.

[0005] The present invention provides a pressure sensor, comprising:

[0006] A pressure sensitive element having a pressure chamber, the element having a longitudinally extending wall with a closed longitudinal proximal end, the front portion of the wall forming a longitudinally extending elastic diaphragm; the elastic diaphragm deforms in response to the pressure of a pressure medium to be measured within the pressure chamber, and the deformation is converted into a corresponding electrical signal by a pressure measurement circuit attached to the outer surface of the elastic diaphragm;

[0007] A supporting element comprising a main body portion located on a longitudinal proximal side of the pressure sensitive element, the main body portion having a forward mounting plane;

[0008] And an electronic module assembly, including a circuit board arranged longitudinally and extending left and right; the rear side of the circuit board is fixed to the mounting plane, and the front side forms a membrane plane provided with a processing circuit, and the processing circuit is electrically contacted to the pressure measurement circuit through a plurality of conductive springs.

[0009] Preferably, the pressure measuring circuit has a plurality of electrical contacts, the projections of which onto the membrane plane face away from the pressure chamber.

[0010] Preferably, the pressure sensor further comprises a plurality of terminals, the middle portion of which is embedded in the main body portion and one end of which passes through the mounting plane forward and is electrically connected to the processing circuit of the circuit board.

[0011] Preferably, the one end of the terminal passes through the mounting plane forward and is then vertically soldered to a first metallized hole provided on the circuit board.

[0012] Preferably, the one end of the terminal passes through the mounting plane forward and is vertically pressed into a first metallized hole provided on the circuit board.

[0013] Preferably, the conductive spring comprises an elastic portion with one end facing backwards and electrically contacting the processing circuit, and a rod portion formed by the other end of the elastic portion protruding forwards, and the rod portion is welded to a second metallized hole provided on the circuit board.

[0014] Preferably, the pressure sensor also includes a pressure interface having a pressure introduction channel for introducing the pressure medium to be measured and a metal cylindrical shell arranged longitudinally and connected to the pressure interface at its longitudinal distal end; the longitudinal distal end of the surrounding wall is sealingly connected to an inner end of the pressure introduction channel; the supporting element extends longitudinally and includes a terminal button portion, the main body portion and a supporting portion connected in sequence from near to far along the longitudinal direction; the terminal button portion extends outward from a top opening arranged at the longitudinal proximal end of the cylindrical shell; the main body portion is pressed toward the longitudinal distal end by the longitudinal proximal end of the cylindrical shell, and the supporting portion is supported on the pressure interface toward the longitudinal distal end.

[0015] Preferably, the support portion comprises a plurality of longitudinally extending and circumferentially spaced support legs extending from the outer edge of the main body toward the longitudinal distal end, and the longitudinal distal ends of the support legs are circumferentially positioned and supported on the longitudinal proximal end of the pressure interface.

[0016] Preferably, one inner end of the pressure introduction channel extends toward the longitudinal proximal end to form a connecting tube, and the longitudinal distal end of the surrounding wall is sealingly connected to the connecting tube; the peripheral wall of the connecting tube extends laterally outward to form a disk body, and accordingly, an annular stress isolation groove is left between the disk body and the longitudinal proximal surface of the pressure interface.

[0017] Preferably, the support leg is snap-connected to the pressure interface.

[0018] The pressure sensor of the present invention can form a reliable electrical connection between the circuit board and the pressure sensitive element without completely fixing the supporting element to the pressure interface. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 FIG. 4 is a cross-sectional view of a pressure sensor according to a preferred embodiment.

[0020] Figure 2 A front view of a pressure sensitive element according to a preferred embodiment. DETAILED DESCRIPTION

[0021] The technical solution of the present application will be clearly and completely described below in conjunction with the accompanying drawings. The following embodiments are exemplary and are only used to explain the present application and are not to be construed as limiting 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.

[0022] In the description of this application, it should be understood that the terms "upper", "lower", "inner", "outer", "left", "right", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or the orientations or positional relationships in which the product of this application is conventionally placed when in use, or the orientations or positional relationships conventionally understood by those skilled in the art. These are only for the convenience of describing this application and simplifying the description, and do 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 understood as a limitation on this application. In addition, the prepositive terms "first", "second", "third", etc. are only used to distinguish the modified objects, and cannot be understood as indicating or implying relative importance.

[0023] In addition, the terms "mounted," "connected," and "connected" should be interpreted broadly. For example, they can refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0024] It should be further understood that the term “and / or” used in this specification and the corresponding claims refers to any and all possible combinations of one or more of the listed items.

[0025] like Figures 1 to 2In a preferred embodiment of the present invention, the pressure sensor comprises at least a pressure sensitive element 4, a supporting element 3 and an electronic module assembly 5. The pressure sensitive element 4 has a longitudinal extension and a longitudinal proximal end (i.e. Figure 1 The upper end of the pressure sensitive element 4 is enclosed by a wall 41, and the front part of the wall 41 forms a longitudinally extending elastic diaphragm 41a. The wall 41 encloses a pressure chamber 40, and the longitudinal proximal end of the pressure chamber 40 is enclosed by a wall 42. The elastic diaphragm 41a generates corresponding deformation after receiving the pressure of the pressure medium to be measured in the pressure chamber 40 on the inside, and converts the deformation into a corresponding electrical signal through the pressure measurement circuit 410 attached to its outer surface. The support element 3 may include a main body 32 located on the longitudinal proximal end side of the pressure sensitive element 4, and the main body 32 may have a forward mounting plane 32b. The electronic module assembly 5 may include a circuit board 51 arranged longitudinally and extending left and right. The rear side of the circuit board 51 is fixed to the mounting plane 32b. The front side of the circuit board 51 forms a membrane plane on which a processing circuit (not marked) is provided.

[0026] For example only, the measuring circuit is a piezoresistive measuring circuit, such as Figure 2 As shown, the measurement circuit may include two piezoresistors 410 a and two piezoresistors 410 b , which together form a Wheatstone bridge. A plurality of electrical contacts 4101 extend from the Wheatstone bridge.

[0027] The processing circuit electrically contacts the pressure measurement circuit 410 through several conductive springs 52. For example, the conductive springs 52 may include an elastic portion 522 with one end facing rearward to electrically contact the processing circuit, and a rod 521 formed by the other end of the elastic portion 522 extending forward. The rod 521 is soldered to a metallized hole 51a provided on the circuit board 51. The elastic portion 522 may have a bent structure, so that the elasticity of the bent structure in the front-to-back direction allows the rearward electrical contact to the electrical contact portion 4101 of the processing circuit. Preferably, the projection of the electrical contact portion 4101 on the membrane plane avoids the pressure chamber 40 to avoid interference with the measurement circuit. Preferably, the left and right sides of the surrounding wall 41 can be relatively thickened to form thickened portions 4100. This allows the electrical contact portion 4101 to have a larger adjustable range across the left and right width of the membrane plane. The lower end of the circuit board 51 may extend downward beyond the mounting plane 32b to form a suspended portion, and the metallized hole 51a may be provided in this suspended portion. Compared with the prior art, it increases the available area of ​​the circuit board 51. In addition, in order to make the circuit board 51 as close as possible to the central axis of the shell 2, the pressure sensitive element 4 can be eccentrically arranged with respect to the pressure interface 1 on the side away from the circuit board 51.

[0028] The pressure sensor also includes several terminals 310. The middle part of the terminal 310 is embedded in the main body 32, and one end thereof forms a vertical part 3101 extending forward and backward to be perpendicular to the circuit board 51. The front end of the vertical part 3101 passes forward through the mounting plane 32b and is electrically connected to the metallized hole 51b on the circuit board 51.

[0029] To secure the circuit board 51 to the mounting plane 32b, the left and right sides of the circuit board 51 can be locked to the mounting plane 32b by a plurality of snap fasteners formed by corresponding portions of the main body 32 protruding forward. Alternatively or additionally, the circuit board 51 can be riveted to the mounting plane 32b by a plurality of heat rivet studs formed by protruding downward from the main body 32, or the rear side of the circuit board 51 can be directly bonded to the mounting plane 32b. The front end of the vertical portion 3101 can be welded to the metallized hole 51b. More preferably, the front end of the vertical portion 3101 can form a fisheye portion (not shown), which is pressed into the metallized hole 51b and forms a tight fit with the metallized hole 51b, thereby simultaneously forming a mechanical connection and an electrical connection.

[0030] For example, the pressure sensor may further include a pressure interface 1 and a metal shell 2. The pressure interface 1 may have a pressure introduction channel 10 for introducing the pressure medium to be measured. A portion of the pressure introduction channel 10 may be defined by an inner cavity of a pressure interface tube 13 formed by extending the pressure interface 1 toward the longitudinal distal end. The longitudinal distal end of the shell 2 may be fixed to a circle of steps 1b formed on the upper end of the pressure interface 1. The longitudinal distal end ( Figure 1 The lower end of the cylindrical shell 2) can be sealably connected to the inner end of the pressure introduction channel 10. The support element 3 extends longitudinally and may include a terminal button portion 31, the above-mentioned main body portion 32 and a support portion 33 connected in sequence from near to far along the longitudinal direction. The terminal button portion 31 extends outward from a top opening 32c provided at the longitudinal proximal end of the cylindrical shell 2. The main body portion 32 is pressed toward the longitudinal distal end by the longitudinal proximal end of the cylindrical shell 2, and the support portion 33 is supported on the pressure interface 1 toward the longitudinal distal end. The upper end of the cylindrical shell 2 can extend radially inward to form a pressing portion (not marked), and the pressing portion is pressed downward onto a step 32a formed on the support element 3. A sealing ring 320 can be provided between the step 32a and the pressing portion.

[0031] Preferably, the support portion 33 may include a plurality of longitudinally extending and circumferentially spaced support legs 331 extending from the outer edge of the main body portion 32 toward the longitudinal distal end, and the longitudinal distal ends of the support legs 331 are circumferentially positioned and supported on the step 1a formed at the longitudinal proximal end of the pressure interface 1. A circumferential interval 33a is formed between each two adjacent support legs 331, and the circumferential angle of each circumferential interval 33a is less than 180 degrees. The support legs 331 can be snapped into the pressure interface 1. For example, the inner root of the step 1a can form a slot 1c, and the longitudinal distal end of the support leg 331 can protrude radially inward to form an anti-slip protrusion 3311. The anti-slip protrusion 3311 is snapped into the above-mentioned slot 1c to prevent the support element 3 from detaching from the pressure interface 1 toward the longitudinal proximal end.

[0032] Preferably, one inner end of the pressure introduction channel 10 can extend toward the longitudinal proximal end to form a connecting tube 11, and the longitudinal distal end of the surrounding wall 41 is sealedly connected to the connecting tube 11. The peripheral wall of the connecting tube 11 extends outward in the transverse direction to form a disc 12. Accordingly, an annular stress isolation groove (not marked) is left between the disc 12 and the longitudinal proximal surface of the pressure interface 1. At least one of the support legs 331 can protrude radially inward to form a longitudinally extending circumferential positioning rib 3312. The outer wall of the connecting tube 11 can extend outward to form a disc 12. The disc 12 can be provided with a circumferential positioning groove 12a that runs vertically through it. The circumferential positioning rib 3312 is cooperatively arranged in the circumferential positioning groove 12at, thereby forming circumferential positioning between the support element 3 and the pressure interface 1.

[0033] Preferably, the pressure sensor may further include an auxiliary support element 6. The auxiliary support element 6 may include at least one downwardly projecting support leg 631. The lower end of the support leg 631 may project radially inward to form an anti-slip protrusion 6311 that engages with the retaining groove 1c. The auxiliary support element 6 may be secured to the support element 3 via a snap-fit ​​connection or other means. This allows the support element 3 to be more reliably supported on the pressure port 1.

[0034] The scope of the disclosure is defined not by the detailed description, but 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 disclosure.

Claims

1. A pressure sensor, characterized in that: include: A pressure sensitive element (4) having a pressure chamber, which has a longitudinally extending surrounding wall (41) with a closed longitudinal proximal end, wherein the front portion of the surrounding wall (41) forms a longitudinally extending elastic diaphragm (41a); the elastic diaphragm (41a) receives the pressure of the pressure medium to be measured in the pressure chamber on its inner side and generates corresponding deformation, and converts the deformation into a corresponding electrical signal through a pressure measurement circuit (410) attached to its outer surface; A supporting element (3), comprising a main body (32) located on a longitudinal proximal side of the pressure sensitive element (4), wherein the main body (32) has a forward-facing mounting plane (32b); and an electronic module assembly (5), comprising a circuit board (51) arranged longitudinally and extending left and right; the rear side of the circuit board (51) is fixed to the mounting plane (32b), and the front side thereof forms a membrane plane provided with a processing circuit, the processing circuit being electrically contacted rearwardly to the pressure measurement circuit (410) through a plurality of conductive springs (52).

2. The pressure sensor according to claim 1, wherein The pressure measuring circuit (410) has a plurality of electrical contacts (4101), the projections of which onto the membrane plane avoid the pressure chamber.

3. The pressure sensor according to claim 1, wherein It also includes a plurality of terminals (310) of which the middle portion is embedded in the main body (32) and one end of which passes through the mounting plane (32b) forward and is electrically connected to the processing circuit of the circuit board (51).

4. The pressure sensor according to claim 3, characterized in that The one end of the terminal (310) passes through the mounting plane (32b) forward and is then vertically welded to a first metallized hole (51b) provided on the circuit board (51).

5. The pressure sensor according to claim 4, characterized in that The one end of the terminal (310) passes through the mounting plane (32b) forward and is then vertically pressed into a first metallized hole (51b) provided on the circuit board (51).

6. The pressure sensor according to claim 1, wherein The conductive spring (52) comprises an elastic portion (522) with one end facing backward and electrically contacting the processing circuit, and a rod portion (521) formed by the other end of the elastic portion (522) protruding forward, wherein the rod portion (521) is welded to a second metallized hole (51a) provided on the circuit board (51).

7. The pressure sensor according to any one of claims 1 to 6, characterized in that It also includes a pressure interface (1) having a pressure introduction channel (10) for introducing the pressure medium to be measured and a metal shell (2) arranged longitudinally and connected to the pressure interface (1) at its longitudinal distal end; the longitudinal distal end of the surrounding wall (41) is sealedly connected to the inner end of the pressure introduction channel (10); the support element (3) extends longitudinally and includes a terminal button portion (31), the main body portion (32) and a support portion (33) connected in sequence from near to far along the longitudinal direction; the terminal button portion (31) extends outward from a top opening (32c) arranged at the longitudinal proximal end of the shell (2); the main body portion (32) is pressed toward the longitudinal distal end by the longitudinal proximal end of the shell (2), and the support portion (33) is supported on the pressure interface (1) toward the longitudinal distal end.

8. The pressure sensor according to claim 7, characterized in that The support portion (33) includes a plurality of longitudinally extending and circumferentially spaced support legs (331) extending from the outer edge of the main body (32) toward the longitudinal distal end, and the longitudinal distal ends of the support legs (331) are circumferentially positioned and supported on the longitudinal proximal end of the pressure interface (1).

9. The pressure sensor according to claim 8, characterized in that One inner end of the pressure introduction channel (10) extends toward the longitudinal proximal end to form a connecting pipe (11), and the longitudinal distal end of the surrounding wall (41) is sealedly connected to the connecting pipe (11); the peripheral wall of the connecting pipe (11) extends outward in the transverse direction to form a disc body (12), and accordingly, an annular stress isolation groove is left between the disc body (12) and the longitudinal proximal surface of the pressure interface (1).

10. The pressure sensor according to claim 8, wherein The support leg (331) is snap-connected to the pressure interface (1).

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