Pressure sensor

Abstract

A pressure sensor comprises a shell defining an installation cavity, the shell comprises a metal pressure interface, an electric connector and a metal shell, and the metal shell comprises a circle of welding part, a circle of outer side part formed by upward extension of the outer edge of the welding part and an inner side part formed by upward extension of the inner edge of the welding part towards the interior of the installation cavity. The lower side surface of the outer side part is hermetically welded to the pressure interface; the inner end of the pressure connector is communicated to the mounting cavity; the electric connector comprises a supporting part which extends downwards, the lower end of the supporting part is supported on the upper side surface of the welding part, and the upper end of the outer side part presses the electric connector to the welding part downwards; the pressure sensitive element is hermetically fixed at the inner end of the pressure introduction channel; a seat press-molded on the inner side portion and having a hole capable of accommodating at least a portion of the pressure sensitive element; the electronic module assembly is fixed on the seat and is electrically connected to the pressure sensitive element through an electric connecting wire; and the metal housing is arranged above the electronic module assembly in a covering manner.

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 prior art, a pressure sensor typically includes a pressure interface, a housing, and an electrical connector that enclose an inner cavity. A pressure-sensitive element and an electronic module assembly are disposed within the inner cavity. The electronic module assembly needs to be electrically connected to the pressure-sensitive element via leads. Because these leads are relatively fragile, the electronic module assembly needs to be securely fixed before the leads are connected. For example, US Pat. No. 6,453,747 B1 discloses a pressure sensor in which the electronic module assembly is disposed on a support member that is removably snapped onto the base end of the diaphragm portion. This mounting method, firstly, creates mounting stress when the support member and the base end engage, which can easily interfere with the measuring diaphragm. Secondly, the support member and the electronic module assembly can still experience slight relative displacement, which can easily cause the leads to fall off, especially during prolonged operation under vibration conditions. Even if the leads are protected by covering them with gel, the effect is still limited. Moreover, the gel covering the surface of the measuring diaphragm can also slightly interfere with the measurement results. Summary of the Invention

[0003] In response to the deficiencies of the prior art, the present application provides a pressure sensor to support the electronic module assembly while minimizing interference with pressure-sensitive elements.

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

[0005] A housing enclosing a mounting cavity includes a metal pressure port, an electrical connector, and a metal shell. The metal shell includes a ring-shaped welding portion, an outer portion extending upward from the outer edge of the welding portion, and an inner portion extending upward from the inner edge of the welding portion into the mounting cavity. The lower surface of the outer portion is seal-welded to the pressure port. The pressure port has an inner end connected to the mounting cavity. The electrical connector includes a support portion extending downward and having its lower end supported on the upper surface of the welding portion. The upper end of the outer portion presses the electrical connector downward against the welding portion.

[0006] A pressure sensitive element sealed and fixed to the inner end of the pressure introduction channel;

[0007] a seat molded onto the inner portion and having a hole for receiving at least a portion of the pressure sensitive element;

[0008] an electronic module assembly fixed on the seat and electrically connected to the pressure sensitive element via electrical connecting wires, which is electrically connected to a plurality of connecting terminals fixed on the electrical connector;

[0009] and a metal cover, which is arranged above the electronic module assembly.

[0010] Preferably, the outer edge of the cover is joined to or partially overlaps with the upper edge of the upper end of the inner portion.

[0011] Preferably, the edge portion of the cover case is electrically connected to the upper end of the inner portion.

[0012] Preferably, the edge portion of the cover shell arches downward to form a first abutting portion, and the first abutting portion electrically contacts the upper end of the inner portion downward.

[0013] Preferably, the cover is torn downward to form a sheet-shaped third abutting portion, and the third abutting portion is downwardly electrically contacted with the upper end of the inner portion.

[0014] Preferably, the cover is torn downward to form a sheet-shaped second abutting portion, and the second abutting portion is downwardly electrically contacted with a grounding terminal of the electronic module assembly.

[0015] Preferably, the connecting terminal includes at least one grounded first terminal, the first terminal being electrically connected to a ground terminal of the electronic module assembly, and the first terminal being electrically connected to the first terminal via a first coil spring.

[0016] Preferably, the first coil spring includes a sparsely coiled first elastic part, whose two axial ends are integrally connected with a relatively tightly coiled first rigid part and a second rigid part, and the outer diameters of the first rigid part and the second rigid part gradually decrease toward the side away from the first elastic part to form a conical outer contour; the end of the second rigid part away from the first elastic part is also integrally connected with a sparsely coiled second elastic part, and the outer diameter of the second elastic part is smaller than the outer diameter of the first elastic part; the cover is provided with a through hole for the second elastic part to pass through, and the edge of the through hole is pressed toward the side away from the first elastic part to form a trumpet-shaped crimping surface that elastically electrically contacts the conical outer contour of the second rigid part upward; the lower end of the second elastic part is elastically electrically contacted with a grounding terminal of the electronic module assembly.

[0017] Preferably, the electrical connector is provided with a holding hole for holding at least a portion of the first elastic portion.

[0018] Preferably, the middle portion of the cover is depressed upward to form a cup-shaped portion, and the cup-shaped portion is fixedly buckled into a cavity formed by the upward depression of the electrical connector.

[0019] The pressure sensor of the present application is molded together with a metal shell and a seat, thereby providing support for the electronic module assembly while avoiding interference with the pressure sensitive element as much as possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1is a schematic structural diagram of the pressure sensor according to the first embodiment;

[0021] Figure 2 is a schematic structural diagram of a pressure sensor according to a second embodiment;

[0022] Figure 3 is a schematic structural diagram of a pressure sensor according to a third embodiment;

[0023] Figure 4 is a schematic structural diagram of a first coil spring according to a third embodiment;

[0024] Figure 5 is a partial structural diagram of a pressure sensor according to a third embodiment;

[0025] 6(a) to (c) are schematic structural diagrams of some variations of the electrical connection structure of the third embodiment;

[0026] Figure 7 is a schematic structural diagram of a pressure sensor according to a fourth embodiment;

[0027] Figure 8 A top view of a portion of the structure of the fourth embodiment; DETAILED DESCRIPTION

[0028] 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.

[0029] 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.

[0030] 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.

[0031] 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.

[0032] First embodiment:

[0033] like Figure 1 As shown. The pressure sensor 100 of the first embodiment includes a shell (not marked) that encloses a mounting cavity 10, and the shell includes a pressure interface 11, an electrical connector 15, and a metal shell 12 that seals and connects the pressure interface 11 and the electrical connector 15. The pressure interface 11 is located on the lower side of the electrical connector 15, and includes a pressure introduction channel 110. The outer end of the pressure introduction channel 110 is connected to the pressure medium to be measured, and the inner end of the pressure introduction channel 110 is sealed and coupled to a pressure sensitive element 102. The pressure sensitive element 102 is used to convert the pressure of the pressure medium into an electrical signal. A seat 13 and an electronic module assembly 14 fixed to the seat 13 are provided in the mounting cavity 10. The electronic module assembly 14 is electrically connected to the pressure sensitive element 102 to process the electrical signal measured by the pressure sensitive element 102. When the pressure sensitive element 102 is a passive device (resistance element, capacitance element, etc.), the electronic module assembly 14 also supplies power to its pressure sensitive element 102. In this embodiment, a metal diaphragm can be used as a pressure sensitive element, and a measuring circuit composed of strain resistors is insulatedly arranged on its upper surface to convert the strain generated by the metal diaphragm under the action of the pressure medium into an electrical signal. The measuring circuit is electrically connected to the electronic module assembly 14. Preferably, the metal diaphragm is arranged horizontally.

[0034] The pressure port 11 includes at least one metal portion, and the metal shell 12 includes at least a welded portion 121 sealably welded to the metal portion of the pressure port 11. The outer edge of the welded portion 121 extends upward to form an outer portion 122, and the inner edge of the welded portion 121 extends upward toward the mounting cavity 10 to form an inner portion 123 integrally molded within the seat 13. A groove 12a is formed between the inner portion 123, the welded portion 121, and the outer portion 122. The pressure port 11 is preferably made of metal. The metal shell 12 can be manufactured by stamping.

[0035] The pressure interface 11 may include an interface portion 111 forming the above-mentioned pressure introduction channel 110 and a plate-shaped portion 112 (i.e., the above-mentioned metal portion) connected to the interface portion 111 and welded to the welding portion 121. For example, the upper portion of the interface portion 111 may protrude outward to form a disc-shaped connecting portion 11a, and the disc-shaped connecting portion 11a is sleeved and welded to the hole 11c formed on the plate-shaped portion 112. The lower end of the disc-shaped connecting portion 11a may extend outward to form a support flange 11b for supporting the plate-shaped portion 112 upward. The lower surface of the welding portion 121 is welded to the upper surface of the plate-shaped portion 112 to form a weld 12c. In some other embodiments, the interface portion 111 may also be integrally connected to the plate-shaped portion 112.

[0036] The electrical connector 15 includes a plug-in portion 151 for connection to an external device, a cover portion 152 that covers the electronic module assembly 14, and a support portion 153 formed by the cover portion 152 extending toward the side of the metal shell 12. The lower end 15a of the support portion 153 is supported on the bottom 12b of the groove 12a (i.e., the upper surface of the welding portion 121). The upper end of the outer portion 122 extends inward to form a crimping portion 125. The crimping portion 125 presses the upward-facing step surface 15b formed on the outer side of the cover portion 152 downwardly against the welding portion 121. The step surface 15b and the crimping portion 125 are sealed by the provision of a sealing ring 101. The crimping portion 125 presses the sealing ring 101 downwardly against the step surface 15b.

[0037] A hole 13a is formed on the seat 13 for accommodating at least a portion of the pressure sensitive element 102. The electronic module assembly 14 includes a horizontally arranged circuit board 141, an electronic component 142, and a plurality of conductive connecting portions 144 arranged on the upper surface of the circuit board 141. The conductive connecting portions 144 are electrically connected to the measurement circuit via electrical connecting wires 143. The circuit board 141 may be provided with a hole 14a that allows the electrical connecting wires 143 to pass through. The pressure sensitive element 102 can be sealedly fixed to a protrusion 113 formed by an inward protrusion of the inner end (i.e., the upper end) of the pressure introduction channel 110 to minimize the height difference between the measurement circuit and the upper surface of the circuit board 141. The circuit board 141 may be provided with a plurality of connection holes (not labeled), and the seat 13 may be formed with connection structures that mate with the connection holes of the circuit board 141. For example, the seat 13 may be formed with connection posts 131 that tightly mate with the connection holes of the circuit board 141. Alternatively or additionally, the seat 13 may be formed with rivet posts 132 that are riveted to the connection holes of the circuit board 141. A gap 109 is left between the bottom of the seat 13 and the disc-shaped connection portion 11a.

[0038] In some other embodiments, a positioning connection can be formed between the electrical connector 15 and the seat 13. For example, the outer wall of the seat 13 can be formed with at least one circumferentially spaced snap-fitting portion 15c (e.g., a snap-fitting groove extending vertically). The inner side of the support portion 153 is formed with several snap-fitting portions 154 that circumferentially position and cooperate with the snap-fitting portions 15c. Furthermore, the snap-fitting portions 154 can also radially abut against the outer periphery of the seat 13 to achieve horizontal positioning. Preferably, the inner portion 223 can include a molded connecting portion (not labeled) and an inner cylindrical portion 124 near the welding portion 121. The inner cylindrical portion 124 can be positioned near the lower end 15a of the support portion 153 to horizontally position it.

[0039] A plurality of connection terminals 150 are fixed to the electrical connector 15, with one inner end of each terminal exposed within the mounting cavity 10 and electrically connected to the circuit board 141 via a flexible electrical connection element 145. Preferably, the flexible electrical connection element 145 comprises a plurality of coil springs. A retaining hole 15d for accommodating and retaining the coil springs is provided on the side of the cover portion 152 facing the circuit board 141. The inner end of the connection terminal 150 is exposed at the bottom (i.e., the upper end) of the retaining hole 15d, and the lower end of the retaining hole 15d may continue to extend into the mounting cavity 10 to form an outer extension 15e. One end of the coil spring electrically contacts the inner end 15f of the connection terminal 150, while the other end electrically contacts the circuit board 141. In other embodiments, the flexible electrical connection element 145 may alternatively comprise a flexible plate or a plurality of leaf springs.

[0040] Second embodiment:

[0041] like Figure 2 As shown. The pressure sensor 200 of the second embodiment includes a shell (not marked) that encloses a mounting cavity 20. The shell includes a pressure interface 21, an electrical connector 25, and a metal shell 22 that seals and connects the pressure interface 21 and the electrical connector 25. The pressure interface 21 is located on one side below the electrical connector 25. It includes a pressure introduction channel 210. The outer end of the pressure introduction channel 210 is connected to the pressure medium to be measured, and the inner end of the pressure introduction channel 210 is sealed and coupled to a pressure sensitive element 202. The pressure sensitive element 202 is used to convert the pressure of the pressure medium into an electrical signal. A seat 23 and an electronic module assembly 24 fixed to the seat 23 are provided in the mounting cavity 20. The electronic module assembly 24 is electrically connected to the pressure sensitive element 202 to process the electrical signal measured by the pressure sensitive element 202. When the pressure sensitive element 202 is a passive device (resistor element, capacitor element, etc.), the electronic module assembly 24 also supplies power to its pressure sensitive element 202. In this embodiment, a semiconductor pressure chip can be used as a pressure sensitive element, which includes a diaphragm. A measurement circuit composed of diffusion resistors is provided on the upper surface of the diaphragm to convert the strain generated by the pressure medium into an electrical signal. The semiconductor pressure chip is electrically connected to the electronic module assembly 24.

[0042] The metal shell 22 includes at least a welded portion 221 that is sealably welded to the pressure port 21. The outer edge of the welded portion 221 extends upward to form an outer portion 122. The inner edge of the welded portion 221 extends upward toward the mounting cavity 20 to form an inner portion 223 integrally molded onto the exterior of the seat 23. A groove 22a is formed between the inner portion 223, the welded portion 221, and the outer portion 222.

[0043] The pressure interface 21 may include an interface portion 211 forming the pressure introduction channel 210 and a plate portion 212 connected to the interface portion 211 and welded to a welding portion 221. The plate portion 212 is integrally connected to the upper portion of the interface portion 211. The lower surface of the welding portion 221 is welded to the upper surface of the plate portion 212 to form a weld 22c.

[0044] The electrical connector 25 includes a plug-in portion 251 for connection to the outside, a cover portion 252 positioned over the electronic module assembly 24, and a support portion 253 extending from the cover portion 252 toward the side of the metal shell 22. The lower end 25a of the support portion 253 is supported on the bottom 22b of the groove 22a (i.e., the upper surface of the welding portion 221). The upper end of the outer portion 222 extends inward to form a crimping portion 225, which presses the upward-facing step surface 25b formed on the outer side of the cover portion 252 downward against the welding portion 221. A sealing ring 201 is provided between the step surface 25b and the crimping portion 225 to achieve a seal. Preferably, the lower portion of the inner portion 223 can be recessed inward to form an annular cavity (not shown) between the inner portion 223 and the support portion 253. The annular cavity is sealed with a sealing ring 26 to seal between the inner portion 223 and the support portion 253. In this way, a double seal can be formed to better protect the components in the installation cavity 20.

[0045] The electronic module assembly 24 includes a horizontally arranged circuit board 241, electronic components 242 disposed on the upper surface of the circuit board 241, and a plurality of conductive connectors 244. The conductive connectors 244 are electrically connected to the measurement circuit via electrical conductors 243. The circuit board 241 may be provided with holes 24a for the electrical conductors 243 to pass through. The pressure sensor 202 can be sealedly mounted on a boss 213 formed by an inwardly projecting projection from one end of the inner side of the pressure introduction channel 210 to minimize the height difference between the measurement circuit and the upper surface of the circuit board 241. The base 23 is formed with a hole 23a for the boss 213 to pass upward. The circuit board 241 can be mounted within a downwardly formed recess at the top of the base 23, with several latches 233 securing the edges of the circuit board 241 to the base 23. A gap 209 is provided between the base 23 and the plate-shaped portion 212.

[0046] In some other solutions, a positioning connection may be formed between the electrical connector 25 and the seat 23 , for example, the electrical connector 25 and the seat 23 may be positioned together by a plurality of positioning holes and positioning posts respectively provided on the electrical connector 25 and the seat 23 .

[0047] A plurality of connection terminals 250 are fixed to the electrical connector 25, and one inner end of each terminal is exposed within the mounting cavity 20 and electrically connected to the circuit board 241 via a flexible electrical connection element 245. Preferably, the flexible electrical connection element 245 is a coil spring. A retaining hole 25d for accommodating and retaining the coil spring is provided on the side of the cover portion 252 facing the circuit board 241. The inner end of the connection terminal 250 is exposed at the bottom (i.e., the upper end) of the retaining hole 25d, and the lower end of the retaining hole 25d can continue to extend into the mounting cavity 20 to form an outer extension 25e. One end of the coil spring electrically contacts the inner end 25f of the connection terminal 250, and the other end electrically contacts the circuit board 241. In other embodiments, the flexible electrical connection element 245 can also be a flexible plate or a leaf spring.

[0048] Preferably, the pressure sensor 200 of this embodiment further includes a metal cover 27 fixedly disposed within the mounting cavity 20 and positioned over the electronic module assembly 24. The cover 27 can be fixed to the base 23. For example, its edge portion 272 can be provided with connection holes (not labeled) that tightly fit over connection posts 231 extending upward from the base 23. The cover 27 is preferably electrically connected to the upper end 226 of the inner portion 223. For example, the outer edge of the edge portion 272 can extend downward to form a cylindrical portion 271, which then electrically contacts the outer periphery of the upper end 226 to electrically connect to the metal shell 22. The outer edge of the cover 27 preferably partially overlaps or engages with the upper edge of the upper end 226 of the inner portion 223 to enclose the electronic module assembly 24 therein.

[0049] Thus, the electronic module assembly 24 is effectively electromagnetically shielded by the housing 27, the pressure interface 21, and the metal shell 22. The housing 27 is provided with a via (not labeled) through which the flexible electrical connection element 245 passes. Furthermore, the housing 27 is preferably grounded to discharge static electricity. For example, the housing 27 can be electrically connected to a ground terminal on the circuit board 241 via a ground connector 203. The ground connector 203 can be a conductive sheet, one end of which can be soldered to a ground terminal on the circuit board 241, while the other end can be penetrated by a connecting post 231 and clamped between the housing 27 and the base 23.

[0050] Third embodiment:

[0051] like Figure 3As shown. The pressure sensor 300 of the third embodiment includes a shell (not marked) that encloses a mounting cavity 30. The shell includes a pressure interface 31, an electrical connector 35, and a metal shell 32 that seals the pressure interface 31 and the electrical connector 35. The pressure interface 31 is located on the lower side of the electrical connector 35 and includes a pressure introduction channel 310. The outer end of the pressure introduction channel 310 is connected to the pressure medium to be measured, and the inner end of the pressure introduction channel 310 is sealedly coupled to a pressure sensitive element 302. The pressure sensitive element 302 is used to convert the pressure of the pressure medium into an electrical signal. A seat 33 and an electronic module assembly 34 fixed to the seat 33 are provided in the mounting cavity 30. The electronic module assembly 34 is electrically connected to the pressure sensitive element 302 to process the electrical signal measured by the pressure sensitive element 302. When the pressure sensitive element 302 is a passive device (resistor element, capacitor element, etc.), the electronic module assembly 34 also supplies power to the pressure sensitive element 302. In this embodiment, a semiconductor pressure chip can be used as a pressure sensitive element, which includes a diaphragm. A measurement circuit composed of diffusion resistors is provided on the upper surface of the diaphragm to convert the strain generated by the pressure medium into an electrical signal. The semiconductor pressure chip is electrically connected to the electronic module assembly 34.

[0052] The metal shell 32 includes at least a welded portion 321 that is sealed against the pressure port 31. The outer edge of the welded portion 321 extends upward to form an outer portion 122. The inner edge of the welded portion 321 extends upward toward the mounting cavity 30 to form an inner portion 323 integrally molded onto the exterior of the seat 33. A groove 32a is formed between the inner portion 323, the welded portion 321, and the outer portion 322.

[0053] The pressure interface 31 may include an interface portion 311 forming the pressure introduction channel 310 and a plate portion 312 connected to the interface portion 311 and welded to a welding portion 321. The plate portion 312 is integrally connected to the upper portion of the interface portion 311. The lower surface of the welding portion 321 is welded to the upper surface of the plate portion 312 to form a weld 32c.

[0054] The electrical connector 35 includes a plug-in portion 351 for connecting to the external device, a cover portion 352 positioned over the electronic module assembly 34, and a support portion 353 extending from the cover portion 352 toward the metal shell 32. The lower end 35a of the support portion 353 is supported on the bottom 32b of the groove 32a (i.e., the upper surface of the soldering portion 321). The upper end of the outer portion 322 extends inward to form a crimping portion 325, which presses the upward-facing step surface 35b formed on the outer side of the cover portion 352 downward against the soldering portion 321. A sealing ring 301 is provided between the step surface 35b and the crimping portion 325. Preferably, the lower portion of the inner portion 323 can be recessed inward to form an annular cavity (not shown) between the inner portion 323 and the support portion 353. A sealing ring 36 is sealed within the annular cavity to seal between the inner portion 323 and the support portion 353. This creates a double seal, better protecting the components within the mounting cavity 30.

[0055] The electronic module assembly 34 includes a horizontally arranged circuit board 341, electronic components (not labeled) disposed on the upper surface of the circuit board 341, and multiple conductive connectors (not labeled). Electrical connections are established between the conductive connectors and the measurement circuit via electrical conductors 343. The circuit board 341 may include a hole 34a for the electrical conductors 343 to pass through. The pressure sensor 302 can be sealedly mounted on a protrusion 313 formed by an inwardly extending projection from one end of the inner side of the pressure introduction channel 310 to minimize the height difference between the measurement circuit and the upper surface of the circuit board 341. The seat 33 includes a hole 33a for the protrusion 313 to pass upward. The circuit board 341 can be mounted within a downwardly formed recess at the top of the seat 33, with several latches 333 securing the edges of the circuit board 341 to the seat 33. A gap 309 is provided between the bottom of the seat 33 and the plate-shaped portion 312.

[0056] In some other embodiments, a positioning connection can be formed between the electrical connector 35 and the seat 33, for example, the positioning can be achieved by a plurality of positioning holes (not marked) and positioning posts (not marked) respectively provided on the electrical connector 35 and the seat 33.

[0057] A plurality of connection terminals 350 are fixed to the electrical connector 35, with one inner end of each terminal exposed within the mounting cavity 30 and electrically connected to the circuit board 341 via a flexible electrical connection element. Preferably, the flexible electrical connection element comprises a plurality of coil springs 38. A retaining hole 35d is defined on the side of the cover portion 352 facing the circuit board 341 to accommodate and retain the coil springs 38. The inner ends of the connection terminals 350 are exposed at the bottom (i.e., the upper end) of the retaining hole 35d, while the lower end of the retaining hole 35d extends further into the mounting cavity 30 to form an outer extension 35e. One end of the coil spring 38 electrically contacts the inner end 35f of the connection terminal 350, while the other end electrically contacts the circuit board 341.

[0058] Preferably, the pressure sensor 300 of this embodiment further includes a metal housing 37 fixedly disposed within the mounting cavity 30 and positioned over the electronic module assembly 34. The housing 37 is provided with a through-hole (not labeled) through which a coil spring 38 passes. A raised portion (not labeled) is formed upwardly in the middle of the housing 37, which is secured to a recessed cavity (not labeled) formed at the bottom of the cover portion 252. An edge portion 372 of the housing 37 arches downwardly to form a first abutment portion 37a. The first abutment portion 37a electrically contacts the upper end 326 of the inner portion 323. The first abutment portion 37a may be in the form of a raised dot. In other embodiments, alternatively or additionally, the housing 37 may be torn downwardly to form a sheet-like third abutment portion 37c. The third abutment portion 37c electrically contacts the upper end 326 of the inner portion 323. The middle part of the cover shell 37 can also be pressed upward to form a cup-shaped part 371 and the cup-shaped part 371 can be fixedly buckled into the concave cavity 356 formed by the upward depression of the lower end of the cover part 352. The cup-shaped part 371 and the inner wall of the concave cavity 356 can be conveniently fixed together through the cooperating clamping action between the cup-shaped part 371 and the inner wall of the concave cavity 356.

[0059] The edge of the cover 37 is torn downward to form a second abutting portion 37b in the form of a sheet. The second abutting portion 37b is electrically in contact with a ground terminal 346 on the electronic module assembly 34, thereby electrically connecting the cover 37 to the ground terminal of the electronic module assembly 34. The second abutting portion 37b can be omitted, and the cover 37 can be directly connected to the ground terminal in the connection terminal 350. For details, please refer to Figure 4 . The above-mentioned multiple coil springs 38 include a first coil spring 381 and a plurality of second coil springs 382. The above-mentioned multiple connection terminals 350 include a first terminal 354 and a plurality of second terminals 355. Among them, one end of the first coil spring 381 is electrically connected to the first terminal 354, and the other end of the first coil spring 381 is electrically connected to the conductive connection part 344 on the circuit board 341; one end of the second coil spring 382 is electrically connected to each of the second terminals 355, and the other end is electrically connected to the conductive connection part 345 on the circuit board 341. Among them, the second coil spring 382 can be an ordinary metal coil spring, and the structure of the first coil spring 381 is different from that of the second coil spring 382, please refer to Figure 5The first coil spring 381 comprises a sparsely coiled first elastic portion 38b, with a relatively tightly coiled first rigid portion 38a and a second rigid portion 38c integrally connected at its axial ends. The outer diameters of the first and second rigid portions 38a, 38c gradually decrease toward the side away from the first elastic portion 38b, forming a tapered outer profile. The second rigid portion 38c is also integrally connected to the end away from the first elastic portion 38b with a sparsely coiled second elastic portion 38d. The outer diameter D2 of the second elastic portion 38d is smaller than the outer diameter D1 of the first elastic portion 38b. The housing 37 is provided with a through hole 374 for the passage of the second coil spring 382. The housing 37 also has a through hole 375 to allow the second elastic portion 38d of the first coil spring 381 to pass downward. The edge of the through hole 375, recessed toward the side away from the first elastic portion 38b, forms a bell-shaped crimping surface 373 that elastically and electrically contacts the tapered outer profile of the second rigid portion 38c, compressing the first elastic portion 38b upward. Because the cover 37 is fixed to the electrical connector 35, during assembly, the electrical connector 35 can also compress the second elastic portion 38d toward the circuit board 341. This electrical connection structure in this embodiment facilitates electrical contact between the first terminal 354, the conductive connection portion 344, and the cover 37 via the first coil spring 381. The cross-section of the bell-shaped crimping surface 373 (a cross-section taken perpendicular to the spring plane) gradually increases toward the first terminal 354 and is preferably a tapered surface.

[0060] Figures 6(a) to 6(c) also illustrate three alternative embodiments for electrically connecting the first terminal 354, the housing 37, and the conductive connecting portion 344 via alternative electrical connection structures. Below, the first element 391, the second element 392, and the third element 393 are abstractly described as the first terminal 354, the housing 37, and the conductive connecting portion 344, respectively. It should be understood that the aforementioned connection relationship between the first terminal 354, the housing 37, and the conductive connecting portion 344 is equally applicable even when the first element 391, the second element 392, and the third element 393 are used as replacements.

[0061] As shown in FIG6( a ), in a first variation of the electrical connection structure, the electrical connection structure comprises three elements spaced axially along a first coil spring 381: a first element 391, a second element 392, and a third element 393. The first coil spring 381 comprises a sparsely coiled first elastic portion 38b, connected at both ends to a relatively tightly coiled first rigid portion 38a and a second rigid portion 38c. The outer diameters of the first and second rigid portions 38a, 38c gradually decrease toward the side away from the first elastic portion 38b, forming a tapered outer profile. The end of the second rigid portion 38c, away from the first elastic portion 38b, is further connected to a sparsely coiled second elastic portion 38d. The outer diameter of the second elastic portion 38d is smaller than that of the first elastic portion 38b. The first coil spring 381 also comprises a sparsely coiled third elastic portion 38e, connected to the side of the first elastic portion 38b away from the second elastic portion 38d. The second element 392 is provided with a through hole 39b to allow the second coil spring 382 to pass through. A flared crimping surface 39a formed within the through hole 39b, facing the first elastic portion 38b, resiliently and electrically contacts the tapered outer contour of the first rigid portion 38a, thereby axially compressing the first and second elastic portions 38b, 38c, toward the third element 393. The outer end of the third elastic portion 38e (i.e., the end distal from the first elastic portion 38b) resiliently and electrically contacts the first element 391, while the outer end of the second elastic portion 38d (i.e., the end distal from the first elastic portion 38b) resiliently and electrically contacts the third element 393. The third elastic portion 38e is retained within a retaining hole 39c formed in a fourth element 394. The fourth element 394 can be fixedly connected to the first element 391, preferably located at the bottom of the retaining groove 39c. The third elastic portion 38e is compressed by the first element 391 toward the first elastic portion 38b. In this way, the elastic parts and the tapered outer contour provided on both sides are in contact with the third element, thereby achieving common electrical connection among the first element 391 , the second element 392 and the third element 393 .

[0062] As shown in Figure 6(b), the difference between the second variant embodiment of the electrical connection structure and the first variant embodiment is that a trumpet-shaped crimping surface 39a formed in the through hole 39b facing the side of the third elastic part 38e is elastically electrically contacted with the conical outer contour of the second rigid part 38c, and causes the first elastic part 38b to be axially compressed toward the side of the third element 393.

[0063] As shown in FIG6(c), the first variation of the electrical connection structure differs from the second variation in that the retaining groove 39c is omitted. Instead, the first coil spring 381 is directly fixed to the second element 392 via a fourth element 395, thereby maintaining the first coil spring 381 in a suitable axial position. Specifically, a through hole 39d is formed in the fourth element 395 to allow the third elastic portion to pass upward. The edge of the through hole 39d is recessed toward the side away from the second element 392 to form a bell-shaped crimping surface 39e facing toward 38b. The bell-shaped crimping surface 39e elastically and electrically contacts (either electrically or non-electrically) the tapered outer contour of the first rigid portion 38a toward the side of the second element 392 (i.e., toward the first elastic portion 38b). The fourth element 394 can be an electrical conductor or an electrical insulator.

[0064] In various variations of this electrical connection structure, each elastic portion is compressed. Furthermore, when the third elastic portion 38e is present, it can be replaced by a tightly coiled third rigid portion (not labeled). In this case, the third elastic portion 38e is compressed. The third rigid portion and the first elastic portion 38b can be collectively referred to as the intermediate coiled portion, or encompassed by the intermediate coiled portion. The central axes of the various portions of the first coiled spring 381 extend in the same direction (i.e., the direction of arrangement of the first element 391, the second coiled spring 382, and the third element 393), i.e., are collinear. Preferably, the through hole 39b accommodates at least a portion of the first elastic portion 38b to retain the first elastic portion 38b.

[0065] Fourth embodiment:

[0066] like Figure 7 、 Figure 8As shown. The pressure sensor 500 of the fourth embodiment includes a shell (not marked) that encloses a mounting cavity 50, and the shell includes a pressure interface 51, an electrical connector 55, and a metal shell 52 that seals and connects the pressure interface 51 and the electrical connector 55. The pressure interface 51 is located on the lower side of the electrical connector 55, and includes a pressure introduction channel 510. The outer end of the pressure introduction channel 510 is connected to the pressure medium to be measured, and the inner end of the pressure introduction channel 510 is sealed and coupled to a pressure sensitive element 502. The pressure sensitive element 502 is used to convert the pressure of the pressure medium into an electrical signal. A seat 53 and an electronic module assembly 54 fixed to the seat 53 are provided in the mounting cavity 50. The seat 53 includes a first part 531 and a second part 532, and the second part 532 extends approximately vertically. The electronic module assembly 54 is electrically connected to the pressure sensitive element 502 to process the electrical signal measured by the pressure sensitive element 502. When the pressure-sensitive element 502 is a passive device (resistor, capacitor, etc.), the electronic module assembly 54 also provides power to the pressure-sensitive element 502. In this embodiment, a metal diaphragm can be used as the pressure-sensitive element. A measurement circuit composed of strain gauge resistors is insulatedly provided on its side surface to convert the strain generated by the metal diaphragm under the action of the pressure medium into an electrical signal. The measurement circuit is electrically connected to the electronic module assembly 54. Preferably, the pressure-sensitive element 502 includes a vertical diaphragm 503. The measurement circuit is provided on a vertical surface 504 provided on the outside of the vertical diaphragm 503. The inside of the vertical diaphragm 503 is connected to the pressure introduction channel 510.

[0067] The pressure port 51 includes at least one metal portion, and the metal shell 52 includes at least a welded portion 521 sealably welded to the metal portion of the pressure port 51. The outer edge of the welded portion 521 extends upward to form an outer portion 122, and the inner edge of the welded portion 521 extends upward toward the side of the mounting cavity 50 to form an inner portion 523 integrally molded within the first portion 531. A groove 52a is formed between the inner portion 523, the welded portion 521, and the outer portion 522. Preferably, the inner portion 523 may include a molded connecting portion (not labeled) and an inner cylindrical portion 524 adjacent to the welded portion 521. The inner cylindrical portion 524 may be adjacent to the lower end 55a of the support portion 553 to horizontally position it. A gap 509 is provided between the bottom of the seat 53 and the plate-shaped portion 512.

[0068] The pressure interface 51 may include an interface portion 511 forming the above-mentioned pressure introduction channel 510 and a plate-shaped portion 512 (i.e., the above-mentioned metal portion) connected to the interface portion 511 and welded to the welding portion 521. For example, the upper portion of the interface portion 511 may protrude outward to form a disc-shaped connecting portion 51a, which is sleeved and welded to a hole 51c formed in the plate-shaped portion 512. The lower end of the disc-shaped connecting portion 51a may extend outward to form a support flange 51b for supporting the plate-shaped portion 512 upward. The lower surface of the welding portion 521 is welded to the upper surface of the plate-shaped portion 512 to form a weld 52c. In some other embodiments, the interface portion 511 may also be integrally connected to the plate-shaped portion 512.

[0069] The electrical connector 55 includes a cover portion 552 and a support portion 553 extending from the cover portion 552 toward one side of the metal shell 52. The lower end 55a of the support portion 553 is supported on the bottom 52b of the groove 52a (i.e., the upper surface of the welding portion 521). The upper end of the outer portion 522 extends inward to form a crimping portion 525, which presses the upward-facing step surface 55b formed on the outer side of the cover portion 552 downward against the welding portion 521. A sealing ring 501 is provided between the step surface 55b and the crimping portion 525. The support portion 553 of the electrical connector 55 is circumferentially positioned and covered on the outside of the seat 53. For example, a vertically extending positioning groove 534 can be provided on the outer wall of the second portion 532, and the inner wall of the support portion 553 can be extended inward to form a vertical positioning portion 555, which is disposed within the positioning groove 534.

[0070] A hole 53a is formed in the first portion 531 for accommodating at least a portion of the pressure-sensitive element 502. The lower end of the second portion 532 is connected to the left and right sides of the first portion 531. The electronic module assembly 54 includes a vertically arranged circuit board 541, an electronic component 542, and a plurality of first conductive connecting portions 544 arranged on a side surface of the circuit board 541. The measurement circuit on the vertical surface 504 is located on the upper side of the upper end of the first portion 531, and the vertical surface 504 is arranged parallel to the circuit board 541. The first conductive connecting portion 544 is electrically connected to the measurement circuit via an electrical connection wire 543. The pressure-sensitive element 502 can be sealedly arranged on a protrusion 513 formed by an inward protrusion of the inner end of the pressure introduction channel 510.

[0071] The lateral ends of the circuit board 541 are respectively inserted downwardly into two insertion slots 53e formed in the second portion 532. The openings of the two insertion slots 53e are arranged in a direction opposite each other. The lower end of the circuit board 541 is positioned and supported on the upper end of the first portion 531. In this way, the circuit board 541 is stably fixed to the base 53. In some other embodiments, the circuit board 541 can also be additionally fixed in the insertion slots 53e using adhesive.

[0072] A plurality of connection terminals 550 are fixed to the electrical connector 55, and one inner end of each terminal is electrically connected to the circuit board 541. For example, a first electrical contact element 546 may be molded on the second portion 532. The first electrical contact element 546 comprises a first vertical portion 54c disposed on the sidewall of the insertion slot 53e facing the circuit board 541, and a first transverse portion 54a disposed on the upper surface of the second portion 532. The first vertical portion 54c is electrically connected to a second conductive connection portion 545 disposed on the circuit board 541 via an electrical connection wire 548. A second electrical contact element 547 may also be molded on the second portion 532. The second electrical contact element 547 comprises a second vertical portion 54d disposed on the sidewall of the second portion 532, and a second transverse portion 54e exposed on the upper surface of the second portion 532 and extending horizontally. The second vertical portion 54d is electrically connected to a second conductive connection portion 545 disposed on the circuit board 541 via an electrical connection wire 549. The inner end 55f of the connection terminal 550 is connected to the first transverse portion 54a or the second transverse portion 54e via a flexible electrical connection element 540. The second portion 532 has a generally arcuate horizontal cross-section and forms an opening 533 circumferentially opposite the vertical surface 504. This facilitates electrical connection between the measurement circuit on the outer surface of the vertical surface 504 and the first conductive connection portion 544 via an electrical connection wire 543. The first transverse portion 54a and the first vertical portion 54c are connected via an embedded portion 54b embedded within the second portion 532. The second transverse portion 54e can be disposed on the sidewalls of an extension portion 53d formed by extending from the circumferential edges of the opening 533 away from the circuit board 541.

[0073] The flexible electrical connection element 540 can be a flexible plate, a coil spring, or a leaf spring. In this embodiment, the flexible electrical connection element 540 can be an electrical contact spring whose lower end forms elastic electrical contact with the first transverse portion 54a or the second transverse portion 54e, and whose upper end is tightly coiled to form a rigid portion with a conical outer profile. The above-mentioned connection terminal 550 can also be integrally connected to the above-mentioned rigid portion and has a certain degree of rigidity due to the tight coiling, thereby being able to be plugged into an external device. Correspondingly, a stepped retaining hole 55d can be formed in the electrical connector 55, and a downward-facing crimping surface (not marked) is formed on the inner wall of the retaining hole 55d, and the crimping surface is elastically and electrically contacted downward on the rigid portion.

[0074] 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 housing enclosing a mounting cavity includes an electrical connector, a metal pressure interface, and a metal shell. The metal shell includes a ring-shaped welding portion, an outer portion extending upward from the outer edge of the welding portion, and an inner portion extending upward into the mounting cavity from the inner edge of the welding portion. The lower surface of the outer portion is seal-welded to the pressure interface. The pressure interface has an inner end connected to a pressure interface of the mounting cavity. The electrical connector includes a downwardly extending support portion, the lower end of which is supported on the upper surface of the welding portion. The upper end of the outer portion presses the electrical connector downwardly against the welding portion. A pressure sensitive element sealed and fixed to the inner end of the pressure introduction channel; a seat molded onto the inner portion and having a hole for receiving at least a portion of the pressure sensitive element; an electronic module assembly fixed on the seat and electrically connected to the pressure sensitive element via electrical connecting wires, which is electrically connected to a plurality of connecting terminals fixed on the electrical connector; and a metal cover, which is arranged above the electronic module assembly.

2. The pressure sensor according to claim 1, wherein The outer edge of the cover is joined to or partially overlaps with the upper edge of the upper end of the inner portion.

3. The pressure sensor according to claim 1, wherein The edge portion of the cover case is electrically connected to the upper end of the inner portion.

4. The pressure sensor according to claim 1, wherein The edge of the cover shell arches downward to form a first abutting portion, and the first abutting portion electrically contacts the upper end of the inner portion downward.

5. The pressure sensor according to claim 1, wherein The cover shell is torn downward to form a sheet-shaped third abutting portion, and the third abutting portion is downwardly electrically contacted with the upper end of the inner portion.

6. The pressure sensor according to claim 5, characterized in that The cover is torn downward to form a sheet-shaped second abutting portion, and the second abutting portion is downwardly electrically contacted with a grounding terminal of the electronic module assembly.

7. The pressure sensor according to claim 5, characterized in that The connecting terminal includes at least one grounded first terminal, the first terminal being electrically connected to a ground terminal of the electronic module assembly, and the first terminal being electrically connected to the first terminal via a first coil spring.

8. The pressure sensor according to claim 7, characterized in that The first coil spring includes a sparsely coiled first elastic part, and its two axial ends are integrally connected with a relatively tightly coiled first rigid part and a second rigid part, and the outer diameters of the first rigid part and the second rigid part gradually decrease toward the side away from the first elastic part to form a conical outer contour; the end of the second rigid part away from the first elastic part is also integrally connected with a sparsely coiled second elastic part, and the outer diameter of the second elastic part is smaller than the outer diameter of the first elastic part; the cover is provided with a through hole for the second elastic part to pass through, and the edge of the through hole is pressed toward the side away from the first elastic part to form a trumpet-shaped crimping surface that elastically electrically contacts the conical outer contour of the second rigid part upward; the lower end of the second elastic part is elastically electrically contacted with a grounding terminal of the electronic module assembly.

9. The pressure sensor according to claim 8, characterized in that: The electrical connector is provided with a holding hole for holding at least a portion of the first elastic portion.

10. The pressure sensor according to claim 7, wherein: The middle part of the cover shell is pressed upward to form a cup-shaped part, and the cup-shaped part is fixedly buckled in a cavity formed by the upward depression of the electric connector.

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