Pressure sensor

Abstract

A pressure sensor capable of reducing stress interference of pressing force on a pressure sensitive element comprises a shell internally provided with a mounting cavity, and a pressure guide hole communicated to the mounting cavity is formed in the bottom of the shell; the seat body is arranged at the bottom of the mounting cavity and comprises a disc-shaped main body part which is arranged along the longitudinal direction in the axial direction, the longitudinal top surface of the main body part extends along the transverse direction, and the main body part comprises a first supporting part and a second supporting part surrounding the periphery of the first supporting part; a ring groove for separating the first supporting part from the second supporting part is formed between the top surface of the first supporting part and the top surface of the second supporting part; the second supporting part is pressed towards one side of the bottom, so that the seat body is sealed to one end of the inner side of the pressure guide hole through a first sealing ring; the pressure sensitive element is fixed on the top surface of the first supporting part; a pressure via hole formed in a seat body of the pressure sensitive element is communicated to the pressure guide hole; and the electronic module assembly is arranged in the mounting cavity and is electrically connected to the pressure sensitive element.

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 existing pressure sensors, the top of the shell is usually riveted to form a pressure edge to provide a pressing force to press the base downward so that it forms a pressure seal between the sealing ring and the shell, thereby isolating the components inside the sensor from the pressure medium to be measured. However, when the pressure of the pressure medium to be measured is relatively high, the pressure edge may not be sufficient to provide the above-mentioned pressing force. In addition, under the action of a large pressing force, the pressure sensitive element is easily disturbed by the above-mentioned pressing force, resulting in a large measurement error. On the other hand, when the base of the pressure sensitive element is pressed by the pressing force, it is easy to cause stress interference to the pressure sensitive element fixed on the base. Utility Model Content

[0003] In view of the deficiencies in the prior art, the present application provides a pressure sensor to solve at least one of the above-mentioned deficiencies.

[0004] To achieve the above objectives, the present application provides the following technical solution: a pressure sensor comprising:

[0005] A housing having an installation cavity therein, wherein a pressure-inducing hole communicating with the installation cavity is provided at the bottom of the housing;

[0006] A seat body is provided at the bottom of the installation cavity, comprising a disc-shaped main body portion arranged axially in the longitudinal direction, the longitudinal top surface of the main body portion extending in the transverse direction, the main body portion comprising a first support portion and a second support portion surrounding the periphery of the first support portion; a circular groove is formed between the top surfaces of the first support portion and the second support portion to separate the two; the second support portion is pressed toward the bottom side so that the seat body is sealed to the inner end of the pressure-inducing hole through a first sealing ring;

[0007] A pressure sensitive element fixed to the top surface of the first supporting portion, wherein a pressure through hole provided on the seat is connected to the pressure induction hole;

[0008] and an electronic module assembly disposed in the mounting cavity and electrically connected to the pressure sensitive element.

[0009] Preferably, the electronic module assembly includes a substrate fixed to the top surface of the first supporting portion, and a processing circuit electrically connected to the pressure sensitive element is provided on the top surface of the substrate.

[0010] Preferably, the housing includes an outer shell, the top of the outer shell is recessed toward the bottom to form a groove, and the bottom of the outer shell is formed with the pressure-inducing hole whose top end is connected to the bottom of the groove.

[0011] Preferably, the device further comprises a pressing ring which is arranged in the installation cavity and presses the second supporting portion toward the bottom side.

[0012] Preferably, the pressure ring is interference fit or threadedly connected to the inner wall of the groove.

[0013] Preferably, the shell further comprises a terminal button fixed to one side of the top of the shell by riveting, and the pressure ring is integrally connected to the bottom end of the terminal button.

[0014] Preferably, the top of the shell extends upward to form a circle of thin-walled portion, and the top end of the thin-walled portion is folded inward to form a circle of pressing edge for pressing the terminal button toward the bottom side.

[0015] Preferably, the pressure ring is integrally connected to the lateral inner part of the bottom end of the terminal button, and the lateral outer part of the bottom end of the terminal button seals a second sealing ring against a sealing surface formed on the inner side of the outer shell toward the bottom side.

[0016] Preferably, the first sealing ring is pressed upward against the first supporting portion.

[0017] Preferably, the outer peripheral contour of the first sealing ring faces the groove toward the top side. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a perspective view of the pressure sensor of the first embodiment;

[0019] Figure 2 is a top view of the pressure sensor of the first embodiment;

[0020] Figure 3 The pressure sensor of the first embodiment is Figure 2 A cross-sectional view of AA shown in FIG;

[0021] Figure 4 The pressure sensor of the first embodiment is Figure 2 A cross-sectional view of BB shown in ;

[0022] Figure 5 is a cross-sectional view of a pressure sensor according to a second embodiment;

[0023] 100, pressure sensor; 10, pressure introduction hole; 11a, upper part; 11b, lower part; 11, groove; 12, thin wall part; 13, pressure edge; 1a, sealing groove; 1, shell; 21a, clamping groove; 21, convex part; 22, wall part; 23, main body part; 24, positioning column; 2, end knob; 30a, circumferential positioning part; 30b, groove; 30c, pressure via; 31, main body part; 32, convex part; 3a, first support part; 3b, second support part; 3, seat body; 401, lead wire; 40, pressure sensitive element; 41a, allowance part; 41, substrate; 42, processing circuit; 43, electric connection element; 44, frame; 4, electronic module assembly; 5, pressure ring; 61, horizontal part; 62, vertical part; 6, terminal; 7, sealing ring; 8, sealing ring; 9, sealing ring. DETAILED DESCRIPTION

[0024] The technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. The following examples are exemplary and are used to explain the present application, but cannot be interpreted as a limitation on the present application. In the following description, the same reference signs are used to represent the same or equivalent elements, and repeated descriptions are omitted.

[0025] In the description of the present application, it should be understood that the terms "upper", "lower", "inner", "outer", "left", "right", and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship commonly used when the product of the present application is used, or the orientation or positional relationship commonly understood by those skilled in the art, and are only for the convenience of describing the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the prepositions "first", "second", "third", etc. are only used for the purpose of distinguishing the objects being modified, and cannot be understood as indicating or implying relative importance.

[0026] In addition, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixed connection, or detachable connection, or integrally connected; it can be mechanical connection, or electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or the internal communication of two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0027] It should be further understood that the term "and / or" used in the specification and corresponding claims of the present application means any combination of one or more of the listed items and all possible combinations.

[0028] Please see Figures 1-4In the first embodiment, the pressure sensor 100 includes a housing (not marked), a pressure ring 5, a seat 3 and a sealing ring 9. The housing has an installation cavity inside, which may include a housing 1 and a housing connected to the longitudinal top of the housing 1 ( Figure 3 、 Figure 4 The top of the housing 1 can be turned toward the bottom ( Figure 3 、 Figure 4 The lower part of the housing 1 is recessed on one side to form a groove 11. The bottom of the housing 1 may be formed with a pressure-introducing hole 10 having a top end connected to the bottom of the groove 11. The pressure-introducing hole 10 is used to introduce the pressure medium to be measured into the interior of the sensor.

[0029] The pressure ring 5, base 3, and sealing ring 9 are sequentially positioned within the groove 11 from the top to the bottom. The pressure ring 5 is fixedly attached to the groove 11 and compresses the base 3 toward the bottom. The base 3 has a pressure hole 30c connecting the top and bottom sides thereof. Under the pressure of the pressure ring 5, this hole 30c is sealedly connected to the bottom of the groove 11 via the sealing ring 9. The sealing ring 9 surrounds the bottom end of the pressure hole 30c and the top end of the pressure-introducing hole 10, ensuring sealed communication between the top end of the pressure-introducing hole 10 and the bottom end of the pressure hole 30c.

[0030] The pressure sensor 100 further includes an electronic module assembly 4 and at least one pressure sensitive element 40 . The pressure sensitive element 40 can be fixedly sealed to the top of the pressure through hole 30 c by a sealant to obtain the pressure of the pressure medium to be measured.

[0031] The electronic module assembly 4 includes a substrate 41 fixed to the top of the base 3. A processing circuit 42 is disposed on one side of the top of the substrate 41. The processing circuit 42 is electrically connected to the pressure-sensitive element 40 via leads 401. The substrate 41 may be provided with a hole- or notch-shaped clearance portion 41a to provide space for the pressure-sensitive element 40. A frame 44 surrounding the pressure-sensitive element 40 and leads 401 may also be fixed to one side of the top surface of the substrate 41. The frame 44 is filled with a protective gel (not labeled) that covers the pressure-sensitive element 40 and leads 401.

[0032] The pressure ring 5 can be connected to the inner wall of the groove 11 by interference fit, so that the pressure ring 5 provides sufficient pressing force to the seat body 3. Alternatively, the pressure ring 5 can also be threadedly connected to the inner wall of the groove 11.

[0033] In particular, the seat body 3 can include an axial and longitudinal disc-shaped main body portion 31. The top surface of the main body portion 31 extends in a transverse direction. The main body portion 31 includes a first support portion 3a and a second support portion 3b surrounding the periphery of the first support portion 3a. The substrate 41 can be fixedly attached to the top surface of the first support portion 3a by means of glue. The compression ring 5 can be compressed towards the bottom side to the second support portion 3b. In order to avoid excessive compression force to form stress interference to the pressure sensitive element 40, a groove 30b can be formed between the top surface of the first support portion 3a and the top surface of the second support portion 3b to separate the two.

[0034] In particular, the seat body 3 can include an axial and longitudinal disc-shaped main body portion 31. The top surface of the main body portion 31 extends in a transverse direction. The main body portion 31 includes a first support portion 3a and a second support portion 3b surrounding the periphery of the first support portion 3a. The substrate 41 can be fixedly attached to the top surface of the first support portion 3a by means of glue. The compression ring 5 can be compressed towards the bottom side to the second support portion 3b. In order to avoid excessive compression force to form stress interference to the pressure sensitive element 40, a groove 30b can be formed between the top surface of the first support portion 3a and the top surface of the second support portion 3b to separate the two.

[0035] In other embodiments, preferably, the recess 11 includes an upper portion 11a for accommodating the compression ring 5 and a lower portion 11b for accommodating the sealing ring 9. More preferably, the recess 11 further includes a support step (not labeled) connecting the upper portion 11a and the lower portion 11b in a radial direction. The support step is supported on the bottom of the main body portion 31 towards the top side. In this way, when the sealing ring 9 is compressed towards the bottom side by the compression ring 5 to a predetermined deformation degree to provide a predetermined compression force, the excess compression force is supported by the support step to be offset.

[0036] In order to facilitate the positioning of the sealing ring 9, the seat body 3 can further include a longitudinal disc-shaped main body portion 31 and a protrusion 32 protruding downwards from the bottom of the main body portion 31 and extending into the inside of the sealing ring 9. The bottom end of the pressure via 30c is arranged on the bottom surface of the protrusion 32. In order to facilitate circumferential positioning by assembly equipment when assembling the seat body 3, circumferential positioning portions 30a can be formed on the outer wall of the main body portion 31.

[0037] In some other embodiments, the housing of the pressure sensor 100 can further include a plurality of terminals 6 molded on the end knob 2. One end of the terminals 6 extends into the mounting cavity and is electrically connected to the electronic module assembly 4, and the outer end thereof has an electrical contact surface (not labeled) exposed outside the end knob 2 for making electrical contact with an external device (not shown). In this case, the housing end knob 2 can be fixed to one side of the top of the housing 1 by means of press riveting, and a thin-walled portion 12 is formed on the top of the housing 1 at a position extending upwardly from the lateral middle or the outer side. The top end of the thin-walled portion 12 is pressed inwardly to form a press edge 13 that presses the end knob 2 toward the bottom side. In this case, the end knob 2 can include a wall portion 22 arranged axially and longitudinally, and the press edge 13 presses the top of the wall portion 22 toward the bottom side. The end knob 2 further includes a main body portion 23 integrally connected to the top of the wall portion 22, which can extend generally laterally, and a convex portion 21 extends from the middle of the main body portion 23 toward the top side. The terminals 6 can include a vertical portion 62 and a horizontal portion 61 integrally connected to the top of the vertical portion 62, wherein the bottom end of the vertical portion 62 extends into the mounting cavity and can be electrically connected to the processing circuit 42 by means of an electrical connecting element 43. The top of the vertical portion 62 is exposed outside the convex portion 21 to form the above-mentioned electrical contact surface. Preferably, the main body portion 23 can extend toward the inside of the mounting cavity to form at least one positioning post 24 that passes through a positioning hole (not labeled) in the electrical connecting element 43 and is then fixed to the positioning hole by means of hot riveting. The bottom of the wall portion 22 presses a sealing ring 8 against a sealing surface lb formed on the top of the housing 1 at a position laterally inwardly. The outer periphery of the convex portion 21 can be formed with a clamping groove 21a for facilitating plugging with an external device. In this case, the end knob 2 can be made of an insulating material such as plastic, and the housing 1 can be made of a metal material.

[0038] In this embodiment, the housing 1 can be cylindrical, and preferably has a fixed outer diameter, and a sealing groove la can be formed on the proximal end of the bottom end of the housing 1, and a sealing ring 7 can be arranged in the sealing groove la to facilitate sealing when the housing 1 is connected to a container containing a pressure medium to be measured. In addition, the pressure ring 5, the wall portion 22, the main body portion 31, the convex portion 32, and the substrate 41 are preferably circular or annular, which facilitates processing and press riveting.

[0039] For further details, please refer to Figure 5In the second embodiment, the pressure ring 5 of the pressure sensor 200 can be integrally connected with the inner circumferential portion of the lower end of the wall portion 22, or pressed toward the bottom side by the inner circumferential portion of the lower end of the wall portion 22, and the pressure ring 5 is not fixedly connected with the inner wall of the upper portion 11a, as compared with the first embodiment. In this way, the pressing force toward the bottom side provided to the main body portion 31 is entirely provided by the pressing edge 13. At this time, although the pressing force can be insufficient, the interference of the pressing force to the pressure sensitive element 40 can be reduced.

[0040] More preferably, the pressure ring 5 of the pressure sensor 200 can be integrally connected with the inner circumferential portion of the lower end of the wall portion 22, and in this case, the sufficient pressing force can be provided by the pressing edge 13 by relatively thickening the thin wall portion 12 and the pressing edge 13. In order to avoid the end knob 2 from being pressed to be broken, the structural strength of the end knob 2 (particularly the wall portion 22) can be increased accordingly, for example, a reinforcing structure (for example, a reinforcing rib) can be integrally connected between the convex portion 21 and the wall portion 22, or the wall portion 22 can be combined (for example, molded) with the convex portion 21 made of plastic, and the wall portion 22 can be made of a metal material such as stainless steel having relatively high structural strength.

[0041] The scope of the disclosure is not limited by the detailed description, but is instead defined by the claims, with equivalents of all parts of the claims being included in the disclosure.

Claims

1. A pressure sensor, characterized by The application relates to a pressure sensor, comprising: a housing with an installation cavity in the interior, the bottom of the housing being provided with a pressure lead hole (10) communicating with the installation cavity; a seat body (3) arranged at the bottom of the installation cavity, comprising an axial and longitudinal disc-shaped main body (31), the longitudinal top surface of the main body (31) extending in the transverse direction, the main body (31) comprising a first support part (3a) and a second support part (3b) surrounding the periphery of the first support part (3a); a groove (30b) is formed between the top surface of the first support part (3a) and the top surface of the second support part (3b) to separate the two; the second support part (3b) is pressed towards the bottom side, so that the seat body (3) is sealed to the inner end of the pressure lead hole (10) by a first sealing ring (9); a pressure sensitive element (40) fixed to the top surface of the first support part (3a), a pressure through hole (30c) arranged on the seat body (3) being communicated with the pressure lead hole (10); and an electronic module assembly (4) arranged in the installation cavity and electrically connected to the pressure sensitive element (40).

2. The pressure sensor of claim 1, wherein, The electronic module assembly (4) comprises a substrate (41) fixed to the top surface of the first support part (3a), and a processing circuit (42) arranged on the top surface of the substrate (41) and electrically connected to the pressure sensitive element (40).

3. The pressure sensor of claim 1, wherein, The housing comprises an outer shell (1), the top of the outer shell (1) being recessed towards the bottom side to form a recess (11), and the bottom of the outer shell (1) being provided with the pressure lead hole (10) communicating with the bottom of the recess (11).

4. The pressure sensor of claim 3, wherein, The pressure ring (5) is arranged in the installation cavity and presses the second support part (3b) towards the bottom side.

5. The pressure sensor of claim 4, wherein, The pressure ring (5) is interference-fitted or screw-connected to the inner wall of the recess (11).

6. The pressure sensor of claim 4, wherein, The housing further comprises an end button (2) fixed to the top side of the outer shell (1) by press riveting, and the pressure ring (5) is integrally connected to the bottom end of the end button (2).

7. The pressure sensor of claim 6, wherein, The top of the outer shell (1) extends upwards to form a thin wall part (12), and the top end of the thin wall part (12) is inwardly pressed to form a pressing edge (13) that presses the end button (2) towards the bottom side.

8. The pressure sensor of claim 7, wherein, The pressure ring (5) is integrally connected to the lateral inner side of the bottom end of the end button (2), and the lateral outer side of the bottom end of the end button (2) seals and presses a second sealing ring (8) to a sealing surface formed on the inner side of the outer shell (1) towards the bottom side.

9. The pressure sensor of claim 1, wherein, The first sealing ring (9) is upwardly pressed to the first support part (3a).

10. The pressure sensor of claim 9, wherein, The outer peripheral contour of the first sealing ring (9) is opposite to the groove (30b) towards the top side.

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