Pressure sensor

Abstract

A pressure sensor with a simple structure and an optimized size comprises a main housing which is provided with a pressure introduction channel; one end of the pressure introduction channel is used for introducing a to-be-measured pressure medium, and the second end of the pressure introduction channel penetrates to a mounting plane on one side surface of the main shell; the pressure measuring assembly is mounted on the mounting plane and is provided with a pressure sensitive element which is plugged and coupled to the other end of the pressure introduction channel; the plurality of electrical connection terminals are fixed on the main shell, and one end of each electrical connection terminal is electrically connected to the pressure measuring assembly; and the connecting structure is formed by outwards extending one side of the mounting plane of the main shell and is mechanically connected with external equipment.

Description

Technical Field

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

[0002] Pressure sensors are used to measure the pressure of the pressure medium to be measured. Depending on the measured pressure, they can be divided into three types: absolute pressure, differential pressure, and gauge pressure. When measuring gauge pressure, an air vent is required to obtain the ambient reference pressure. Existing gauge pressure sensors usually have a closed outer shell to protect the pressure measuring component (especially the pressure chip) in its inner cavity from the erosion of moisture in the environment. It needs to obtain the reference pressure through a vent covered by a waterproof and breathable membrane while isolating the external moisture. Since the outer shell of this type of pressure sensor needs to be closed, considering the manufacturability, it usually includes a main shell and at least one cover combined together, and the electrical connection terminals provided on the main shell or on the cover (the cover can also be called a terminal) are electrically connected to the pressure measuring component. However, in some application environments (such as a relatively dry environment or an environment with a protective shell on the outside), the cover may not be necessary. This makes it possible to simplify the structure and optimize the size of this type of pressure sensor.

[0003] On the other hand, to protect the relatively fragile pressure chip and the leads connecting to the measurement circuit, a frame is typically used to surround the pressure chip and leads, filled with a protective gel to protect them from mechanical and chemical influences. While considering omitting the cover to simplify the structure of the aforementioned pressure sensor, the protective gel, in order to simultaneously protect the pressure chip and leads, presents a challenge: the pressure chip and leads still need to be isolated from external moisture. If they are isolated from the external environment by a frame with vents, the vents must be covered with a waterproof, breathable membrane. The protective gel requires vacuum degassing to remove bubbles within the gel, but due to the gel's high viscosity, complete bubble removal is difficult. When using such a frame, we have found that the available vent size is insufficient to ensure smooth degassing due to limitations in the sensor's size, circuit board area, and the edge bonding width of the waterproof, breathable membrane. This can lead to measurement errors or require significantly longer degassing times. Utility Model Content

[0004] In view of the deficiencies in the prior art, the present application provides a pressure sensor to solve at least one of the above technical deficiencies.

[0005] To achieve the above objectives, the present application provides the following technical solution: a pressure sensor comprising:

[0006] The main housing has a pressure introduction channel; one end of the pressure introduction channel is used to introduce the pressure medium to be measured, and the second end thereof penetrates to a mounting plane on a side surface of the main housing;

[0007] a pressure measuring assembly mounted on the mounting plane, comprising a pressure sensitive element that is blocked and coupled to the other end of the pressure introduction channel;

[0008] a plurality of electrical connection terminals fixed to the main housing, one end of which is electrically connected to the pressure measurement assembly;

[0009] and a connection structure formed by extending outward from one side of the installation plane of the main shell and used for mechanical connection with external equipment.

[0010] Preferably, the pressure introduction channel includes a first portion extending longitudinally, and a second portion extending transversely from an inner end of the first portion to the mounting plane, and the pressure measuring assembly is generally arranged longitudinally.

[0011] Preferably, the mounting plane is arranged at the bottom of a recessed portion formed by inward recessing of the one side surface of the main shell.

[0012] Preferably, one end of the electrical connection terminal is electrically connected to the pressure measurement component, and the other end substantially extends longitudinally toward a side away from the pressure measurement component.

[0013] Preferably, the connection structure includes a plurality of buckles formed by extending laterally from one side of the main housing where the pressure measuring assembly is provided.

[0014] Preferably, the pressure measuring component includes a substrate adhered and fixed on the mounting plane; a processing circuit including multiple electronic components is provided on the side of the substrate away from the mounting plane; the processing circuit is electrically connected to the one end of the electrical connection terminal; the pressure sensitive element is fixed on the side of the substrate away from the mounting plane and is electrically connected to the processing circuit through a lead.

[0015] Preferably, the electrical connection terminal comprises a transverse portion and a longitudinal portion that are integrally connected, the transverse portion is electrically connected to the processing circuit, and a middle portion of the longitudinal portion forms an elastic portion having elasticity in the longitudinal direction.

[0016] Preferably, the elastic portion is U-shaped, and two ends of the elastic portion are integrally and vertically connected to two adjacent ends of other parts of the electrical connection terminal.

[0017] Preferably, a protective gel covering at least the pressure sensitive element and the lead is fixedly provided on a side of the substrate away from the mounting plane.

[0018] Preferably, the protective gel is contained in a frame assembly fixed to a corresponding side of the substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a perspective view of the pressure sensor of the first embodiment;

[0020] Figure 2 is a top view of the pressure sensor of the first embodiment;

[0021] Figure 3 The pressure sensor of the first embodiment is Figure 2 A cross-sectional view of AA shown in FIG;

[0022] Figure 4 for Figure 3 An enlarged view of the part B shown in FIG;

[0023] Figure 5 This is a schematic structural diagram of a pressure measurement assembly according to a second embodiment;

[0024] Figure 6 FIG. 4 is a schematic structural diagram of a pressure measurement assembly according to a third embodiment.

[0025] Explanation of reference numerals: 11a, first part; 11b, second part; 11, pressure introduction channel; 12, interface tube; 13, positioning structure; 14, mounting plane; 15, recessed portion; 1, main housing; 20, pressure sensitive element; 21a, pressure through hole; 21b, conductive hole; 21, substrate; 23, electronic component; 24, lead wire; 2, pressure measuring assembly; 31a, cantilever portion; 31b, connecting portion; 31c, buckle portion; 31, first buckle; 32, second buckle; 3, connecting structure; 4, waterproof permeability Air film; 5. Protective gel; 61. Horizontal portion; 62. Longitudinal portion; 63. Elastic portion; 6. Electrical connection terminal; 250. Third adhesive; 251a. Main body; 251b. Second extension portion; 251c. Cover; 251d. Vent; 251. Second frame; 252a. Main body; 252b. First extension portion; 252c. Support portion; 252d. Groove; 252e. Groove inner wall; 252f. Opening; 252g. Third extension portion; 252. First frame; 25. Frame assembly; DETAILED DESCRIPTION

[0026] 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.

[0027] In the description of this application, it should be understood that the terms "upper", "lower", "inside", "outside", "left", "right", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the products of this application are conventionally placed when in use, or are 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 component referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on this application.

[0028] 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.

[0029] 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.

[0030] Please refer to Figures 1 to 3 In the first embodiment, the pressure sensor comprises a main housing 1 extending substantially longitudinally, the main housing 1 having a substantially longitudinal ( Figure 3 The pressure introduction channel 11 extends in the left and right directions. One longitudinal end of the pressure introduction channel 11 is used to introduce the pressure medium to be measured, and the second longitudinal end thereof passes through one side of the main housing 1 ( Figure 3 The pressure sensor further comprises a mounting plane 14 on the mounting plane 14. The pressure sensor further comprises a pressure measuring assembly 2 mounted on the mounting plane 14. The pressure measuring assembly 2 comprises a pressure sensitive element 20 corresponding to the blockage and coupled to the other end of the pressure introduction channel 11. The main housing 1 may be made of a resin material, and a plurality of electrical connection terminals 6 may be molded and fixed thereon. These electrical connection terminals 6 are preferably arranged along Figure 3 The electrical connection terminals 6 are arranged side by side in the front-to-back direction (perpendicular to the paper) as shown in FIG. One end of the electrical connection terminal 6 is electrically connected to the pressure measurement assembly 2, and the other end thereof can generally extend longitudinally toward a side away from the pressure measurement assembly 2 to the outside of the main housing 1 for electrical connection to an external device.

[0031] The mounting plane 14 of the main housing 1 extends outwardly to form a connection structure 3 for mechanical connection with an external device. For example, the connection structure may include a first clip 31 and a second clip 32 extending outward from the side of the main housing 1 where the pressure measurement component 2 is located. These clips can be connected to a plate-shaped or other shaped external device. Figure 1 In order to make the buckle 31 have a certain elasticity in the transverse direction, the first buckle 31 can include a buckle portion 31c, the lower end of the buckle portion 31c extends longitudinally to form a cantilever portion 31a, and the end of the cantilever portion 31a away from the buckle portion 31c is connected to the corresponding front and rear sides of the main housing 1 through the connecting portion 31b. In this way, Figure 1 The "U"-shaped structure composed of the connecting portion 31b, the cantilever portion 31a, and the buckle portion 31c shown in the figure can make the first buckle 31 have a certain degree of elasticity in the vertical direction, which can facilitate the mechanical connection between the first buckle 31 and the external device. Similarly, the second buckle 32 can also adopt a structure similar to the first buckle 31.

[0032] The pressure measurement assembly 2 can also be generally arranged longitudinally. The lower portion of the main housing 1 can extend longitudinally outward toward the end distal from the electrical connection terminals 6 to form a mouthpiece 12. The first portion 11a can be defined by the inner cavity of the mouthpiece 12. A stepped positioning structure 13 can be provided at one outer end of the mouthpiece 12 to facilitate positioning when connected to a fluid interface of a container or pipeline containing the pressure medium to be measured.

[0033] The pressure sensor of this embodiment omits the cover commonly used in the pressure sensor of the prior art, so the structure is simplified; Figure 3 The front-to-back dimensions shown in the figure are relatively small, meaning the main body (excluding the buckle) is generally flat and longitudinally extended. These pressure sensors are particularly suitable for installation in protected enclosed or semi-enclosed spaces such as automobiles, or other less harsh environments.

[0034] In some other solutions, there may be more than one pressure introduction channel 11 and corresponding pressure sensitive element 20. For example, two pressure sensitive elements 20 and two pressure introduction channels 11, or more, may be provided.

[0035] Specifically, the pressure introduction channel 11 may include a first portion 11a extending longitudinally and a second portion 11b extending transversely. The second portion 11b is formed by extending the inner end of the first portion 11a in the transverse direction. The end of the second portion 11b away from the first portion 11a (i.e., Figure 3 Preferably, in order to further reduce the vertical dimension of the pressure sensor, the mounting plane 14 can be provided at the bottom of a recessed portion 15 formed by an inward recess of the upper surface of the main housing 1.

[0036] Specifically, the pressure measurement assembly 2 may include a substrate 21 fixed to the mounting plane 14, at least one pressure sensitive element 20 disposed on the upper side of the substrate 21, and a measurement circuit electrically connected to the pressure sensitive element 20 via a lead 24. The substrate 21 is provided with at least one pressure through-hole 21a extending through both sides of the substrate 21. The pressure sensitive element 20 is correspondingly blocked on one side of the pressure through-hole 21a. The side of the substrate 21 away from the mounting plane 14 (i.e., Figure 3 A processing circuit (not labeled) including a plurality of electronic components 23 is provided on the upper side of the substrate 21. The processing circuit is electrically connected to the end of the electrical connection terminal 6 close to the pressure measurement assembly 2. For example, the corresponding end of the electrical connection terminal 6 can extend upward to form a transverse portion 61 perpendicular to the substrate 21. The substrate 21 can be provided with a conductive hole 21b. The transverse portion 61 can be welded to the conductive hole 21b. The conductive hole 21b is electrically connected to the processing circuit on the upper side of the substrate 21. The pressure sensitive element 20 is fixed to the side of the substrate 21 away from the mounting plane 14 (i.e., Figure 3 ) and is electrically connected to the processing circuit via lead 24.

[0037] Preferably, in order to fix the pressure sensor to the external device while enabling the electrical connection terminal 6 to be easily plugged in, the electrical connection terminal 6 can include the above-mentioned transverse portion 61 and a longitudinal portion 62 that are connected as one piece, and the middle portion of the above-mentioned longitudinal portion 62 forms an elastic portion 63 that is elastic in the longitudinal direction. For example, the elastic portion 63 can be U-shaped, and the two ends of the elastic portion 63 are respectively and vertically connected to the adjacent two ends of other parts of the electrical connection terminal 6 as a whole, and the elastic portion 63 can be formed by the longitudinal portion 62 arching toward the transverse direction.

[0038] Preferably, the pressure measurement assembly 2 may further include at least one frame assembly 25 disposed corresponding to the pressure sensitive element 20. A protective gel 5 is fixedly disposed on a side of the substrate 21 away from the mounting plane 14, covering at least the pressure sensitive element 20 and the leads 24. The protective gel 5 may be housed in a corresponding frame assembly 25 fixed to the corresponding side of the substrate 21.

[0039] The frame assembly 25 may include at least one first frame 252 corresponding to the pressure sensitive element 20 , with an opening 252 f at the upper end thereof and the interior thereof filled with a protective gel 5 .

[0040] Preferably, the frame assembly 25 may further include at least one second frame 251 and at least one waterproof breathable membrane 4. The second frame 251 is assembled and fixed to the corresponding first frame 252. The second frame 251 has a cover 251c that covers the opening 252f. The cover 251c is provided with a vent 251d that extends through the upper and lower sides of the cover 251c. The waterproof breathable membrane 4 is bonded to a generally flat mounting surface provided on the inner side of the cover 251c, thereby covering the upper end of the vent 251d. In other embodiments, the waterproof breathable membrane 4 may also be provided on the lower surface of the cover 251c in other ways, thereby covering the lower end of the vent 251d.

[0041] Please refer to Figure 4 Preferably, the lower end of the first frame 252 extends outward along a plane to form a circle of first extension portions 252b. The first extension portions 252b can be more firmly and hermetically bonded to the upper surface of the substrate 21 using a first adhesive (not shown). More preferably, the lower end of the second frame 251 also extends outward along a plane to form a circle of second extension portions 251b. The second extension portions 251b can be hermetically bonded to the upper surface of the first extension portions 252b using a second adhesive (not shown).

[0042] See also Figure 5 . In the second embodiment, preferably, the upper end of the first frame body 252 may form a third extension portion 252g extending substantially up and down. The third extension portion 252g is integrally connected to the main body 252a of the first frame body 252 through a circle of support portions 252c. The main body 251a of the second frame body 251 may extend up and down, and the lower end of the main body 251a may be supported against the middle of the support portion 252c. The gap between the main body 251a, the third extension portion 252g and the groove 252d is filled with the third adhesive 250. In this way, the main body 251a of the first frame body 251 may be sealingly bonded to the third extension portion 252g by the third adhesive 250. In some other schemes, the lower end of the main body 251a of the first frame body 251 may also extend outwardly with respect to the upper end, for example, it may be a conical cylindrical shape with the top of the cone facing upward. The lower end of the body 251a can rest against the outer edge of the support portion 252c, or fit snugly against the inner wall of the third extension portion 252g. Preferably, the protective gel 5 is positioned lower than the upper edge of the body 252a. This allows the support portion 252c to integrally connect the body 252a and the third extension portion 252g, minimizing measurement errors caused by the tight or threaded fit of the protective gel 5 within the body 252a.

[0043] Preferably, the support portion 252c can be recessed downward to form a circular groove 252d. The inner peripheral wall of the body 251a can be supported against the inner wall 252e of the groove 252d. A portion or all of the third adhesive 250 is contained within the groove 252d. This reduces the risk of the third adhesive 250 overflowing into the inner cavity of the first frame 251 and further reduces the transmission of installation stress to the body 252a.

[0044] See also Figure 6 In the third embodiment, the upper portion of the main body 252a of the second frame 251 extends vertically, and can be tightly or threadably fitted onto the inner wall of the third extension 252g. The upper portion of the main body 252a contracts inward, creating a gap between the main body 252a and the third extension 252g for accommodating at least a portion of the third adhesive 250. The lower end of the main body 251a of the second frame 251 rests downwardly on the support portion 252c, specifically, on the bottom of the groove 252d.

[0045] In each of the above embodiments, the first frame 252 is preferably a metal member. The first frame 252 can provide additional electromagnetic shielding for the pressure-sensitive element 20 and the leads 24. Preferably, the second frame 251 can also be a metal member. In this way, the first frame 252 can form electrical contact with the second frame 251 by supporting it, so that the frame assembly 25 can additionally provide complete electromagnetic shielding for the pressure-sensitive element 20 and the leads 24. In the first embodiment, the second frame 251 can be a metal member, and the first frame 252 can be a metal member or not. In this way, complete electromagnetic shielding can still be achieved. The lower end of the main body 251a of the second frame 251 can be tilted outward relative to the upper end. This can relatively reduce the additional pressure applied to the pressure-sensitive element by the weight of the protective gel 5 itself, as well as pressure fluctuations caused by vibration.

[0046] Preferably, the first frame body 252 and / or the second frame body 251 are thin shell-shaped elements obtained by stamping.

[0047] Preferably, to further ensure reliable electrical contact between the first frame 252 and the second frame 251, the third adhesive 250 can be a conductive adhesive. Similarly, the second adhesive can also be a conductive adhesive. More preferably, the first adhesive can also be a conductive adhesive. In this case, the conductive adhesive can be used to electrically connect the first frame 252 to a ground terminal of the measurement circuit.

[0048] The present application also provides a method for manufacturing a pressure measurement assembly 2, which includes:

[0049] A substrate 21 is provided, on the upper side of which is disposed at least one pressure sensitive element 20 and a measurement circuit electrically connected to the pressure sensitive element 20 via leads 24. At least one pressure via hole 21a is provided on the substrate 21, extending through both sides of the substrate 21. The pressure sensitive element 20 is correspondingly sealed on the upper side of the pressure via hole 21a.

[0050] Provide at least one first frame 252 having an opening 252f at its upper end, seal the lower end of the first frame 252 to the upper side of the substrate 21 with a first adhesive, and enclose the pressure sensitive element 20 within the first frame 252;

[0051] Fill the first frame 252 with a protective gel 5 so that the protective gel 5 at least covers the corresponding pressure sensitive element 20 and lead 24;

[0052] Exhaust the protective gel 5 under negative pressure;

[0053] At least one second frame 251 having a cover 251c is provided, wherein the cover 251c is provided with a vent hole 251d for penetrating the upper and lower sides of the cover 251c;

[0054] The lower end of the second frame 251 is sealedly connected to the first frame 252 by a second adhesive;

[0055] At least one waterproof breathable membrane 4 is provided and bonded to the outer surface of the cover portion 251c.

[0056] The pressure measurement assembly 2 manufactured by the above manufacturing method can independently protect the pressure sensitive element 20 and the lead 24 through the frame assembly 25, while enabling the protective gel filled in the frame assembly 25 to smoothly and efficiently discharge bubbles, thereby reducing the measurement error of the pressure sensor.

[0057] 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: The main housing (1) has a pressure introduction channel (11); one end of the pressure introduction channel (11) is used to introduce the pressure medium to be measured, and the second end thereof is connected to a mounting plane (14) on a side surface of the main housing (1); a pressure measuring assembly (2) mounted on the mounting plane (14), comprising a pressure sensitive element (20) sealed and coupled to the other end of the pressure introduction channel (11); a plurality of electrical connection terminals (6) fixed to the main housing (1), one end of which is electrically connected to the pressure measurement assembly (2); and a connection structure (3) formed by extending outward from one side of the installation plane (14) of the main housing (1) and used for mechanical connection with external equipment.

2. The pressure sensor according to claim 1, wherein The pressure introduction channel (11) includes a first portion (11a) extending longitudinally, and a second portion (11b) extending transversely from an inner end of the first portion (11a) to the mounting plane (14), and the pressure measuring assembly (2) is generally arranged longitudinally.

3. The pressure sensor according to claim 1, wherein The mounting plane (14) is arranged at the bottom of a recessed portion (15) formed by the inward recess of the one side surface of the main housing (1).

4. The pressure sensor according to claim 1, wherein One end of the electrical connection terminal (6) is electrically connected to the pressure measurement component (2), and the other end generally extends longitudinally toward a side away from the pressure measurement component (2).

5. The pressure sensor according to claim 1, wherein The connection structure (3) comprises a plurality of buckles formed by extending laterally from one side of the main housing (1) where the pressure measurement assembly (2) is provided.

6. The pressure sensor according to any one of claims 1 to 5, characterized in that The pressure measurement assembly (2) comprises a substrate (21) fixedly attached to the mounting plane (14); a processing circuit including a plurality of electronic components is provided on a side of the substrate (21) away from the mounting plane (14); the processing circuit is electrically connected to the one end of the electrical connection terminal (6); and the pressure sensitive element (20) is fixed on a side of the substrate (21) away from the mounting plane (14) and is electrically connected to the processing circuit via a lead (24).

7. The pressure sensor according to claim 6, characterized in that The electrical connection terminal (6) comprises a transverse portion (61) and a longitudinal portion (62) connected in one piece, wherein the transverse portion (61) is electrically connected to the processing circuit, and a middle portion of the longitudinal portion (62) forms an elastic portion (63) having elasticity in the longitudinal direction.

8. The pressure sensor according to claim 7, characterized in that The elastic portion (63) is U-shaped, and two ends of the elastic portion (63) are integrally and vertically connected to two adjacent ends of other parts of the electrical connection terminal (6).

9. The pressure sensor according to claim 6, characterized in that A protective gel (5) that covers at least the pressure sensitive element (20) and the lead (24) is fixedly provided on one side of the substrate (21) away from the mounting plane (14).

10. The pressure sensor according to claim 9, characterized in that The protective gel (5) is contained in a frame assembly (25) fixed to a corresponding side of the substrate (21).

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