Pressure measuring assembly and pressure sensor

Abstract

The utility model discloses a pressure measurement assembly and a pressure sensor comprising the pressure measurement assembly. The pressure measuring assembly comprises a substrate which is provided with a pressure via hole penetrating up and down; the pressure measuring element is used for sensing the pressure introduced from the lower end of the pressure via hole and converting the pressure into an electric signal, and the pressure measuring element is arranged at the upper end of the pressure via hole in a sealing manner; the measuring circuit is used for processing the electric signal, is arranged on the upper surface of the substrate in an insulating manner and is electrically connected to the pressure measuring element through a lead; the frame surrounds the pressure measuring element and the lead and is fixed on the upper side of the measuring circuit, a first conductive layer is arranged on the surface of the frame, and the first conductive layer comprises a circle of inner conductive part covering the inner wall of the frame and / or a circle of outer conductive part covering the outer wall of the frame; the frame is filled with protective gel covering the pressure measuring element and the lead. The protective gel can be kept, meanwhile, the electromagnetic shielding capacity is achieved, and meanwhile the certain cost advantage is achieved.

Description

Technical Field

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

[0002] Pressure measuring elements usually use elastic membrane pressure sensitive elements to generate electrical signals by deformation under pressure. These pressure sensitive elements usually need to be encapsulated with protective gel to avoid environmental erosion, and the protective gel is used to maintain its shape through a frame. On the other hand, in order to avoid external electromagnetic interference, these pressure sensitive elements need to add metal shells to provide electromagnetic shielding protection. However, these metal shells need to be made into very thin shells from the perspective of reducing weight and material costs, which makes it difficult to install (especially bonded to) circuit components. Utility Model Content

[0003] In view of the deficiencies of the prior art, the present application provides a pressure measurement component so that it can maintain the protective gel while having electromagnetic shielding capabilities and having certain cost advantages.

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

[0005] A substrate having a pressure via hole penetrating vertically;

[0006] A pressure measuring element for sensing the pressure introduced by the lower end of the pressure through hole and converting it into an electrical signal, which is sealed and arranged at the upper end of the pressure through hole;

[0007] A measuring circuit for processing the electrical signal, which is insulated and disposed on the upper surface of the substrate and electrically connected to the pressure measuring element through a lead wire;

[0008] A frame surrounding the pressure measuring element and the outside of the lead wire is fixed to the upper side of the measuring circuit and has a first conductive layer on its surface. The first conductive layer includes an inner conductive portion covering the inner wall of the frame and / or an outer conductive portion covering the outer wall of the frame. The frame is filled with a protective gel covering the pressure measuring element and the lead wire.

[0009] Preferably, the frame is fixed to the upper side of the measuring circuit by an adhesive, and the first conductive layer is electrically connected to the measuring circuit.

[0010] Preferably, the adhesive is a conductive material, and the lower portion of the first conductive layer is electrically connected to a first conductive portion of the measurement circuit through the adhesive.

[0011] Preferably, the frame further comprises a cover arranged at the upper end, the inner surface and / or outer surface of the cover is provided with a second conductive layer, and the second conductive layer is electrically connected to the first conductive layer.

[0012] Preferably, the first conductive layer includes a circle of outer conductive part covering the outer wall of the frame; the edge of the cover extends toward one side of the frame to form a connecting part, and the connecting part is sleeved on the outer side of the upper part of the frame; the second conductive layer is arranged on the inner surface of the cover and extends along the inner surface of the connecting part to cover the inner wall of the connecting part to form an electrical contact part, and the electrical contact part is electrically contacted with the outer conductive part.

[0013] Preferably, the first conductive layer includes a circle of inner conductive part covering the inner wall of the frame; the edge of the cover extends toward one side of the frame to form a connecting part, and the connecting part is sleeved on the outer side of the upper part of the frame; the second conductive layer is arranged on the outer surface of the cover and extends along the outer surface of the connecting part to cover the outer wall of the connecting part to form an electrical contact part, and the electrical contact part is electrically contacted with the external conductive part.

[0014] Preferably, the first conductive layer includes a circle of top conductive part covering the top surface of the frame; the edge of the cover extends toward one side of the frame to form a connecting part, the connecting part is fixedly sleeved on the upper part of the frame, and the second conductive layer is electrically in contact with the top conductive part.

[0015] On the other hand, the present application provides a pressure sensor, comprising:

[0016] A pressure measuring assembly as described above;

[0017] And a shell, including a lower shell and an upper shell, the upper shell is made of insulating material, one end of a plurality of electrical connection terminals is inserted inwardly into the upper shell and is electrically connected to the measurement circuit of the pressure measurement component through a flexible electrical connection element, and a pressure introduction channel is provided on the lower shell and is sealed and connected to the lower end of the pressure through hole.

[0018] Preferably, at least a portion of the first conductive layer is a metal foil; the flexible electrical connection element includes a plurality of conductive springs, one of the electrical connection terminals is grounded, one end of one of the conductive springs is connected to the grounded electrical connection terminal and the other end of the conductive spring contacts an extension portion extending from the lower end of the metal foil against a second conductive portion on the measuring circuit.

[0019] Preferably, the substrate of the pressure measuring assembly is pressed by the lower shell and the upper shell from the upper and lower sides respectively, and the lower shell includes a metal part; the extension part is pressed by the substrate and conducted to the metal part, or is pressed by the lower shell and conducted to the substrate made of metal material and then indirectly electrically conducted to the lower shell.

[0020] The present application achieves the purpose of electromagnetic protection by providing a conductive layer on the surface of the retaining frame of the protective gel. Compared with the metal shell, it can be manufactured at a lower cost by electroplating or metal foil covering, and has a relatively larger thickness for bonding with the measurement circuit for a larger contact area; further, it can be electrically connected to the measurement circuit through a conductive adhesive to achieve grounding. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic structural diagram of the pressure sensor of the first embodiment;

[0022] Figure 2 It is a structural schematic diagram of the pressure measurement assembly of the first embodiment;

[0023] Figure 3 for Figure 2 An enlarged schematic diagram of the local A shown in FIG.

[0024] Figure 4 is a schematic structural diagram of a pressure sensor according to a second embodiment;

[0025] Figure 5 It is a structural schematic diagram of a pressure measurement assembly of a variation of the third embodiment;

[0026] Figure 6 for Figure 5 The schematic diagram of the structure of the pressure measurement assembly shown before the cover and the frame are assembled;

[0027] Figure 7 for Figure 6 An enlarged schematic diagram of the local B shown;

[0028] Figure 8 It is a structural schematic diagram of a pressure measurement assembly of a variation of the third embodiment;

[0029] Description of reference numerals: 100, pressure sensor; 101, lead; 10, pressure measuring element; 110, through portion; 111a, lower edge; 111, outer conductive portion; 112, first extension section; 113, second extension section; 114, bottom conductive portion; 115, inner conductive portion; 116, top conductive portion; 117, portion; 119, first conductive layer; 11, frame; 121, pressure via hole; 12, substrate; 131, first conductive portion; 13, measuring circuit; 16, adhesive; 17, other electronic components Part; 181, cover body; 182, hole; 183, connection part; 184, inclined guide surface; 18, cover; 191, electrical contact part; 19, second conductive layer; 1, pressure measurement component; 21, pressure introduction channel; 22, groove; 24, first clamping part; 25, thin wall; 26, pressing edge; 2, lower shell; 32, step surface; 33, electrical connection terminal; 34, second clamping part; 3, upper shell; 4a, conductive spring; 4b, conductive spring; 4, flexible electrical connection element; 5, sealing ring; 6, sealing ring. DETAILED DESCRIPTION

[0030] 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 cannot be interpreted as limiting the present application. In the following description, the same symbols are used to represent the same or equivalent elements, and repeated descriptions are omitted.

[0031] In the description of the present 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 the present application are conventionally placed when in use, or are the orientations or positional relationships conventionally understood by those skilled in the art. They are only for the convenience of describing the present 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 should not be understood as a limitation on the present application.

[0032] In addition, the terms "installed", "connected" and "connected" 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, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0033] It should be further understood that the term “and / or” used in the specification and corresponding claims of this application refers to any and all possible combinations of one or more of the listed items.

[0034] like Figure 1 As shown. In the first embodiment, the pressure sensor 100 includes a shell and a pressure measuring assembly 1 arranged in the inner cavity of the shell. The shell is used to accommodate the pressure measuring assembly 1, and introduce the pressure to be measured into the pressure measuring assembly 1 through a pressure medium introduction channel pressure introduction channel 21. The pressure sensor 100 of this embodiment adopts a common shell structure, the shell includes an upper shell 3 and a lower shell 2, wherein the upper shell 3 can be made of insulating material, and the lower shell 2 is made of stainless steel, aluminum or other suitable metal materials, and the two are connected by riveting. The outer edge of the upper end of the lower shell 2 protrudes upward to form a circle of thin wall 25, and the upper end of the thin wall 25 is rolled inward to form a circle of pressing edge 26, and the pressing edge 26 is pressed downward on a step surface 32 formed at the lower end of the upper shell 3. The pressure introduction channel 21 is arranged on the lower shell 2 and communicated with the inner cavity of the shell. The outer end of the pressure introduction channel 21 extends outward and is connected to the outside of the shell from a pressure introduction pipe (not marked) correspondingly formed on the lower shell 2. A sealing ring 6 is provided on the outer wall of the pressure introduction pipe to seal the pressure medium container to be measured.

[0035] Please refer to Figure 2 . The pressure measuring assembly 1 includes a substrate 12 arranged approximately horizontally. The substrate 12 is provided with pressure through holes 121 penetrating both sides in the thickness direction. A pressure measuring element 10 is sealedly provided at the upper end of the pressure through hole 121. The pressure measuring element 10 may be a commonly used pressure measuring element, such as a metal diaphragm pressure measuring element, or a semiconductor pressure measuring element (including a capacitive or piezoresistance type) or other suitable pressure measuring element. The pressure measuring assembly 1 is arranged in the inner cavity of the shell, and the lower end of the pressure through hole 121 is connected to the pressure introduction channel 21 to receive the medium pressure and convert the pressure signal into an electrical signal. Among them, the lower side surface of the substrate 12 is sealedly connected to the lower shell 2. For example, a groove 22 may be provided on the surface of the lower shell 2 facing the substrate 12. Under the pressure of the upper shell 3, the substrate 12 presses the sealing ring 5 into the groove 22, so that the substrate 12 separates the inner cavity of the shell into upper and lower parts. The lower surface of the upper shell 3 and the upper surface of the lower shell 2 respectively form a concave second pressing portion 34 and a concave first pressing portion 24 to accommodate the upper and lower ends of the substrate 12 and limit the substrate 12 in the horizontal direction.

[0036] The pressure measurement assembly 1 also includes a measurement circuit 13 disposed on the upper surface of the substrate 12, and a through portion 110 is provided on the measurement circuit 13 for the pressure measurement element 10 to pass through up and down, and the measurement circuit 13 is electrically connected to the pressure measurement element 10 through a plurality of leads 101. The pressure measurement assembly 1 also includes a frame 11, which surrounds the pressure measurement element 10 and the outside of the lead 101, and is filled with a protective gel (not shown) for covering the pressure measurement element 10 and the through portion 110. The protective gel is used to transmit pressure and protect the electronic components from or mitigate the damage of water vapor or other harsh environments. Other electronic components 17 such as conditioning components or protective capacitors are disposed on the upper surface of the measurement circuit 13. The measurement circuit 13, other electronic components 17, and the frame 11 are all located in the upper part of the inner cavity of the housing. A plurality of electrical connection terminals 33 are disposed on the electrical connection terminal 33, and one end of the inner side of the electrical connection terminal 33 extends into the upper part of the inner cavity and is electrically connected to the measurement circuit 13 through the flexible electrical connection element 4. The flexible electrical connection element 4 may be a flexible circuit board, a lead wire, etc.

[0037] The surface of the frame 11 is provided with a first conductive layer 119, which at least turns into a circle on the horizontal plane, thereby forming electromagnetic shielding protection for the pressure measuring element 10, for example, it may include an outer conductive part 111 arranged on the outside of the frame 11. The first conductive layer 119 can be a coating (for example, made by plating, spraying, etc.), or it can be a conductive foil (for example, aluminum metal foil, etc.). When the first conductive layer 119 is a metal foil, it can be bonded to the outer surface and / or bottom surface and / or top surface of the frame 11 by glue, while the inner surface is not provided or provided with a coating, because the inner surface is usually not easy to bond. The metal foil can be peeled off from the material tape, and it is bonded to the material tape by glue when not in use.

[0038] In this embodiment, the first conductive layer 119 can be electrically connected to the measuring circuit 13, and grounded through the grounding terminal of the measuring circuit 13 to release static electricity. In particular, the first conductive layer 119 can also be electrically connected to the lower housing 2 in an electrically contacting manner through an extension portion extending from the first conductive layer 119, so that the lower housing 2 and the frame 11 reach an equipotential, and the electronic components in the area between the two are prevented from being affected by the electrostatic field. For example, the extension portion may include a first extension section 112 extending from the lower portion of the outer conductive portion 111 toward the horizontal side, or may also include a second extension section 113 extending outward from the first extension section 112. The first extension section 112 may be clamped between the substrate 12 and the upper housing 3, and the second extension section 113 may be clamped between the substrate 12 and the lower housing 2. In particular, when the substrate 12 is made of metal material (such as aluminum, stainless steel), the second extension section 113 can be omitted, and the outer conductive portion 111 can be electrically connected to a metal portion of the lower housing 2 via the first extension section 112 and the substrate 12; when the substrate 12 is made of ceramic material, the outer conductive portion 111 is electrically connected to a metal portion of the lower housing 2 via the first extension section 112 and the second extension section 113. The above-mentioned metal portion preferably includes its thin-walled portion. At this time, it is best to relatively arrange the conductive spring 4b and the frame 11 at a position closer to the edge of the housing.

[0039] In some other embodiments, the structure of the shell may also be other commonly used types, for example, it may include a lower shell 2 and an upper shell 3 both made of plastic. In this case, the lower shell 2 and the upper shell 3 may be bonded together by an adhesive, or locked together by a snap-on structure.

[0040] Please refer to Figure 3 In order to realize the electrical connection between the first conductive layer 119 and the measuring circuit 13, the adhesive 16 can be set as a conductive material. When the bottom of the frame 11 is bonded to the upper surface of the measuring circuit 13 through the adhesive 16, the adhesive 16 covers a first conductive part 131 of the measuring circuit 13. The adhesive 16 infiltrates to the lower edge 111a of the outer conductive part 111 under the action of surface tension, so that the lower edge 111a is electrically connected to the first conductive part 131 through the adhesive 16. Alternatively or additionally, the first conductive layer 119 includes an inner conductive part 115 (see reference 1) disposed on the inner surface of the frame 11. Figure 8 ), the lower edge of the first conductive layer 119 is electrically connected to the first conductive part 131 via the adhesive 16. More preferably, in order to improve the electrical conductivity between the first conductive layer 119 and the first conductive part 131, the first conductive layer 119 further includes a bottom conductive part 114 disposed on the bottom surface of the frame 11, and the bottom conductive part 114 and the first conductive part 131 are electrically connected via the adhesive 16.

[0041] See also Figure 4. On the basis of the first embodiment, a plurality of conductive springs 4a, 4b are used as flexible electrical connection elements in the second embodiment of the present application to make electrical conduction between the measuring circuit 13 and the electrical connection terminal 33. For example, the radius of the lower end of the electrical connection terminal 33 can be reduced so that it can be sleeved inside the upper end of the conductive spring 4a, 4b, and the upper end of the conductive spring 4a, 4b and the lower end of the electrical connection terminal 33 can be additionally fixed by welding. The lower end side of the conductive spring 4a, 4b contacts downwardly against the electrical contact pad (not shown) provided on the measuring circuit 13, thereby forming an electrical connection with the measuring circuit 13.

[0042] In some variant embodiments, the adhesive 16 is not electrically connected to the measuring circuit 13 through the adhesive 16, or is not only electrically connected to the measuring circuit 13 through the adhesive 16, but is additionally or alternatively electrically connected to the measuring circuit 13 through the extension of the first conductive layer 119. For example, the portion 117 of the first extension section 112 formed by the lower extension of the outer conductive portion 111 and close to the frame 11 can be pressed downward by the lower end of one of the portions 117 and electrically contacted with a second conductive portion (not shown) provided on the measuring circuit 13, and the electrical connection terminal 33 corresponding to the conductive spring 4b is a ground terminal. At this time, when the metal lower housing 2 is electrically connected to the frame 11, it is also connected to the ground terminal at the same time.

[0043] See also Figure 5 , Figure 6 , the third embodiment shows another structure of the pressure measurement component 1. In this embodiment, the pressure measurement component 1 may further include a cover 18 sealed on the upper end of the frame 11. The lower surface of the cover 18 has a second conductive layer 19, and the second conductive layer 19 is electrically connected to the cover 18. For example, the cover 18 includes a cover body 181 and a connecting portion 183 formed by the edge of the cover body 181 extending toward the side of the frame 11, and the connecting portion 183 is sleeved on the outer portion of the upper end of the frame 11. The edge of the second conductive layer 19 extends toward the side of the frame 11 along the inner side wall of the connecting portion 183 to form an electrical contact portion 191, and the electrical contact portion 191 is electrically contacted with the upper part of the outer conductive portion 111. In this way, the electromagnetic protection effect of the pressure measurement element 10 can be improved. Among them, a hole 182 can be opened on the cover body 181 to facilitate the introduction of a reference pressure and / or the injection of a protective gel into the pressure measurement element 10. Preferably, the lower end of the inner side wall of the connecting portion 183 is inclined outward to form an inclined guide surface 184, so as to facilitate the sleeve fitting with the outer conductive portion 111. More preferably, Figure 7 As shown, the inner edge of the bottom surface of the frame 11 is inclined downward relative to the outer edge. In this way, firstly, the conductive area and bonding area between the bottom conductive part 114 and the adhesive 16 can be relatively increased, and secondly, more adhesive 16 can be relatively restricted to the outer side, thereby reducing the risk of the adhesive 16 flowing inward and contaminating the lead 101.

[0044] In some other embodiments, the electrical contact portion 191 may be omitted, and the first conductive layer 119 may further include a circle of top conductive portions 116 disposed on the top surface of the frame 11 or distributed in a circumferential direction (see reference 11). Figure 8 ), and electrical contact is made between the top conductive portion 116 and the second conductive layer 19.

[0045] See also Figure 8 In another variation of the third embodiment, the upper surface of the cover 18 has a second conductive layer 19, and the second conductive layer 19 is electrically connected to the cover 18. The edge of the second conductive layer 19 extends along the outer side wall of the connecting portion 183 toward the side of the frame 11 to form an electrical contact portion 191, and the electrical contact portion 191 is in electrical contact with the upper portion of the outer conductive portion 111. The first conductive layer 119 may also include an inner conductive portion 115 covering the inner wall of the frame 11 and / or a top conductive portion 116 covering the top surface of the frame 11. The first conductive layer 119 may be a coating formed by plating.

[0046] In the above embodiments and variations, the frame 11 may be made of plastic or ceramic material, and its shape may be rectangular or circular.

[0047] 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 measurement assembly, characterized in that: include: A substrate (12) having a pressure through hole (121) penetrating from top to bottom; A pressure measuring element (10) for sensing the pressure introduced from the lower end of the pressure through hole (121) and converting it into an electrical signal, and the pressure measuring element (10) is sealingly arranged at the upper end of the pressure through hole (121); A measuring circuit (13) for processing the electrical signal, which is insulated and disposed on the upper surface of the substrate (12) and is electrically connected to the pressure measuring element (10) via a lead (101); A frame (11) surrounding the pressure measuring element (10) and the lead wire (101) is fixed to the upper side of the measuring circuit (13) and has a first conductive layer (119) on its surface, wherein the first conductive layer (119) includes a circle of inner conductive parts (115) covering the inner wall of the frame (11) and / or a circle of outer conductive parts (111) covering the outer wall of the frame (11); the frame (11) is filled with a protective gel covering the pressure measuring element (10) and the lead wire (101).

2. The pressure measurement assembly according to claim 1, characterized in that: The frame (11) is fixed to the upper side of the measuring circuit (13) by means of an adhesive (16), and the first conductive layer (119) is electrically connected to the measuring circuit (13).

3. The pressure measurement assembly according to claim 2, characterized in that: The adhesive (16) is a conductive material, and the lower portion of the first conductive layer (119) is electrically connected to a first conductive portion (131) of the measurement circuit (13) through the adhesive (16).

4. The pressure measurement assembly according to claim 1, characterized in that: It also includes a cover (18) arranged at the upper end of the frame (11), and the inner surface and / or outer surface of the cover (18) is provided with a second conductive layer (19), and the second conductive layer (19) is electrically connected to the first conductive layer (119).

5. The pressure measurement assembly according to claim 4, characterized in that: The first conductive layer (119) includes a circle of outer conductive part (111) covering the outer wall of the frame (11); the edge of the cover (18) extends toward one side of the frame (11) to form a connecting part (183), and the connecting part (183) is sleeved on the upper outer side of the frame (11); the second conductive layer (19) is arranged on the inner surface of the cover (18) and extends along the inner surface of the connecting part (183) to cover the inner wall of the connecting part (183) to form an electrical contact part (191), and the electrical contact part (191) is in electrical contact with the outer conductive part (111).

6. The pressure measurement assembly according to claim 4, characterized in that: The first conductive layer (119) includes a circle of inner conductive parts (115) covering the inner wall of the frame (11); the edge of the cover (18) extends toward one side of the frame (11) to form a connecting part (183), and the connecting part (183) is sleeved on the upper outer side of the frame (11); the second conductive layer (19) is arranged on the outer surface of the cover (18) and extends along the outer surface of the connecting part (183) to cover the outer wall of the connecting part (183) to form an electrical contact part (191), and the electrical contact part (191) is in electrical contact with the outer conductive part (111).

7. The pressure measurement assembly according to claim 4, characterized in that: The first conductive layer (119) includes a circle of top conductive part (116) covering the top surface of the frame (11); the edge of the cover (18) extends toward one side of the frame (11) to form a connecting part (183), the connecting part (183) is fixedly sleeved on the upper part of the frame (11), and the second conductive layer (19) is electrically in contact with the top conductive part (116).

8. A pressure sensor, characterized in that: include: A pressure measuring assembly (1) according to any one of claims 1 to 7; The invention relates to a housing, comprising a lower housing (2) and an upper housing (3), wherein the upper housing (3) is made of insulating material, one end of a plurality of electrical connection terminals (33) is inserted into the upper housing (3) and then electrically connected to a measurement circuit (13) of the pressure measurement assembly (1) through a flexible electrical connection element, and the lower housing (2) is provided with a pressure introduction channel (21) which is sealed and connected to the lower end of the pressure through hole (121).

9. The pressure sensor according to claim 8, characterized in that: At least part of the first conductive layer (119) is a metal foil; the flexible electrical connection element comprises a plurality of conductive springs (4a, 4b); one of the electrical connection terminals (33) is grounded; one end of one of the conductive springs (4b) is connected to the grounded electrical connection terminal (33) and the other end of the conductive spring contacts an extension extending from the lower end of the metal foil against a second conductive portion on the measurement circuit (13).

10. The pressure sensor according to claim 9, characterized in that: The substrate (12) of the pressure measurement component (1) is pressed by the lower shell (2) and the upper shell (3) from upper and lower sides respectively, and the lower shell (2) includes a metal part; the extension part is pressed by the substrate (12) and connected to the metal part, or is pressed by the lower shell (2) and connected to the substrate (12) made of metal material and then indirectly electrically connected to the lower shell (2).

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