Pressure sensor

Abstract

The utility model provides a pressure sensor, which comprises a shell defining a mounting cavity and comprising an end button and a pressure interface which are arranged at two longitudinal ends, and a metal cylindrical shell longitudinally connecting the end button and the pressure interface; the pressure interface is provided with a pressure introduction channel for introducing a to-be-measured pressure medium into the mounting cavity; the pressure measuring element is arranged in the mounting cavity and is hermetically connected to one end of the inner side of the pressure introduction channel; the electronic module assembly is arranged in the mounting cavity and is electrically connected to the pressure measuring element; wherein the top of the cylindrical shell extends inwards in the radial direction and is molded in the end button, and a first retaining hole used for retaining a grounding spring is formed in the end button; the ground spring extends substantially longitudinally and has one end in electrical contact with the top and the other end in electrical contact with the electronics module assembly. According to the pressure sensor, the electric connection between the electronic module assembly and the metal cylinder shell has high reliability.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of sensors, in particular to a pressure sensor. BACKGROUND

[0002] In a type of pressure sensor with a metal cylinder shell, a flexible circuit board connected with a circuit board extends outward to form a spring with a conductive part. When assembled, the inner side of the metal cylinder shell forms an electrical contact with the spring when the metal cylinder shell is assembled downward, thereby forming an electromagnetic shield for the electronic module assembly inside the pressure sensor. The reliability of this grounding electrical connection structure can be further improved. CONTENT OF THE UTILITY MODEL

[0003] In view of the deficiencies of the prior art, the present application provides a pressure sensor that makes the electrical connection with the metal cylinder shell more reliable.

[0004] The utility model provides a pressure sensor, which comprises:

[0005] A housing enclosing an installation cavity, comprising end knobs and a pressure interface arranged at the longitudinal two ends, and a metal cylinder shell longitudinally connecting the end knobs and the pressure interface; the pressure interface has a pressure introduction channel for introducing a pressure medium to be measured into the installation cavity;

[0006] A pressure measurement element arranged in the installation cavity and sealedly connected to one end of the inside of the pressure introduction channel;

[0007] An electronic module assembly arranged in the installation cavity and electrically connected to the pressure measurement element;

[0008] The top of the cylinder shell extends radially inward and is molded into the end knob, and the end knob has a first retaining hole for retaining a grounding spring; the grounding spring extends longitudinally, with one end electrically contacting the top and the other end electrically contacting the electronic module assembly.

[0009] Preferably, the end knob has a plurality of first retaining holes for retaining spiral elastic terminals, the elastic terminals extend longitudinally, with one end electrically contacting the electronic module assembly and the other end extending outward to the outside of the housing.

[0010] Preferably, the elastic terminal is a spiral spring, comprising:

[0011] A first part arranged longitudinally along the central axis and sparsely coiled;

[0012] A second part arranged longitudinally along the central axis and connected to the top end of the first part, comprising a tightly coiled part and a sparsely coiled part connected to the tightly coiled part at the bottom end;

[0013] and a transition portion connecting the top of the first portion and the bottom of the second portion, comprising at least one tapered portion, the tapered portion having a larger outer diameter at its bottom than at its top.

[0014] Preferably, the top end of the sparse coiled portion has a transverse portion.

[0015] Preferably, the elastic terminal further comprises a tapered tail portion connected to the bottom of the first portion, the tapered tail portion having a gradually decreasing outer diameter.

[0016] . The pressure sensor according to any one of claims 1 to 8, wherein the central axis of the first portion and the central axis of the second portion are arranged collinearly, and the maximum outer diameter of the second portion is smaller than the outer diameter of the first portion.

[0017] . The pressure sensor according to any one of claims 1 to 8, wherein the central axis of the first portion and the central axis of the second portion are arranged laterally offset by a distance.

[0018] Preferably, the projections of the outer contours of the tapered portion and the first portion on a transverse plane partially overlap.

[0019] Preferably, further comprising a substantially cylindrical support element for supporting the electronic module assembly; the inner end of the pressure interface longitudinally extends into the interior of the support element and is provided with at least one positioning groove on its peripheral edge, the inner wall of the support element is convex towards the inner side to form a positioning portion cooperating with the positioning groove; the inner end of the pressure introduction channel extends longitudinally towards the interior to form a connecting tube, the middle portion of the connecting tube extends towards the exterior to form a disc; the pressure measuring element comprises a metal diaphragm, the diaphragm is sealingly connected to the side of the disc away from the pressure interface; the edge of the disc forms a first guide groove longitudinally giving way to the positioning portion, one end of the positioning portion is supported on the pressure interface, the other end extends towards the inner side beyond the first guide groove.

[0020] Preferably, the other end of the positioning portion is close to the disc. BRIEF DESCRIPTION OF DRAWINGS

[0021] Figure 1 is a perspective view of the elastic terminal of the first embodiment;

[0022] Figure 2 is a front view of the elastic terminal of the first embodiment;

[0023] Figure 3 is a perspective view of the pressure sensor of the first embodiment;

[0024] Figure 4 is a top view of the pressure sensor of the first embodiment;

[0025] Figure 5 A cross-sectional view of the pressure sensor of the first embodiment along Figure 4 A-A shown in FIG. 1;

[0026] Figure 6 A cross-sectional view of the pressure sensor of the first embodiment along Figure 4 B-B shown in FIG. 1;

[0027] Figure 7 A front view of the elastic terminal of the second embodiment;

[0028] BRIEF DESCRIPTION OF REFERENCE NUMERALS: 100, pressure sensor; 101a, tail portion; 101, first portion; 102a, tightly coiled portion; 102b, sparsely coiled portion; 102c, transverse portion; 102, second portion; 103, transition portion; 104, extension portion; 105, tapered portion; 10, elastic terminal; 110, pressure introduction channel; 11, pressure interface; 120, top portion; 12, barrel; 130, second retaining hole; 133, abutting surface; 13, end knob; 1, housing; 20, diaphragm; 21, pressure measurement circuit; 2, pressure measurement element; 5, external device; 111, coil; 112, connecting tube; 113, positioning groove; 11a, stress isolation groove; 11b, first guide groove; 131, leg portion; 134, first retaining hole; 20a, second guide groove; 22, extension; 23, flexible circuit board; 24, circuit board; 25, processing electronic element; 26, other electronic element; 27, thickened portion; 313, anti-disengagement portion; 314, positioning portion; 31a, first clearance portion; 31b, window; 31, barrel portion; 32a, clearance groove; 32b, second clearance portion; 32, connecting portion; 3, support element; 6, grounding spring; DETAILED DESCRIPTION

[0029] The technical solutions of the present application will be described clearly and completely below in conjunction with the drawings. The following examples are exemplary and are used only to explain the present application, and cannot be interpreted as a limitation on the present application. In the following description, the same reference signs are used to represent the same or equivalent elements, and repetitive descriptions are omitted.

[0030] In the description of the present application, it should be understood that the terms "upper", "lower", "inner", "outer", "left", "right", and the like indicate the orientation or positional relationship shown in the drawings, or the orientation or positional relationship commonly understood by those skilled in the art, or the orientation or positional relationship commonly understood by those skilled in the art, only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the prepositions "first", "second", "third" and the like are only used for the purpose of distinguishing the objects being modified, and cannot be understood as indicating or implying relative importance.

[0031] In addition, the terms "mounting", "connecting", "connecting" should be broadly understood, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, or it can be connected inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0032] It should be further understood that the term "and / or" used in the present application specification and corresponding claims means any combination of one or more of the listed items and all possible combinations.

[0033] As shown in Figure 1 , Figure 2 The elastic terminal 10 of the first embodiment is a spiral spring, which includes a first part 101 with a central axis arranged in the longitudinal direction, and a second part 102 with a central axis arranged in the longitudinal direction, and the central axis of the second part 102 is arranged in line with the central axis of the first part 101. The top end of the first part 101 is integrally connected to the bottom end of the second part 102 through a transition part 103. Among them, the outer diameter of the first part 101 is greater than the maximum outer diameter of the second part 102. The transition part 103 includes a tightly coiled tapered portion 105 (not labeled), the top end of the tapered portion 105 has a smaller outer diameter than the bottom end, the top end of the tapered portion 105 is integrally connected to the top end of the first part 101, and the bottom end of the tapered portion 105 is integrally connected to the bottom end of the second part 102. The tapered portion 105 is preferably tightly coiled and has strong rigidity, so as to be pressed tightly by other elements to the bottom side, and in some other schemes, the tapered portion 105 can also be loosely coiled.

[0034] The second portion 102 includes a tightly coiled portion 102a at the bottom side and a loosely coiled portion 102b at the top side. The outer diameter of the loosely coiled portion 102b can be less than or equal to the outer diameter of the tightly coiled portion 102a. The loosely coiled portion 102b can provide a certain longitudinal flexibility when making longitudinal elastic contact with an external device (which can be a circuit board) while the tightly coiled portion 102a can increase lateral stiffness when making contact with the external device, thereby suppressing lateral displacement of the second portion 102 when making electrical contact with the external device. Figure 3 The loosely coiled portion 102b can provide a certain longitudinal flexibility when making longitudinal elastic contact with an external device (which can be a circuit board) while the tightly coiled portion 102a can increase lateral stiffness when making contact with the external device, thereby suppressing lateral displacement of the second portion 102 when making electrical contact with the external device.

[0035] Preferably, the top of the loosely coiled portion 102b forms a lateral portion 102c extending in the lateral direction, which can provide a larger contact area when making electrical contact with an external device (which can be a circuit board or an electrical contact member), so as to avoid the situation that the helix angle of the second portion 102 causes it to form only a point contact when making longitudinal contact with the external device.

[0036] Please refer to Figures 3-6 . Figures 3-6 A pressure sensor 100 including a plurality of elastic terminals 10 is shown. The pressure sensor 100 includes a housing 1 enclosing a mounting cavity, and an electronic module assembly (not labeled) and at least one pressure measuring element 2 disposed in the mounting cavity. The pressure measuring element 2 is connected to a pressure medium to be measured through a pressure introduction channel 110 to obtain the pressure of the medium to be measured. The pressure measuring element 2 converts the pressure into an electrical signal and transmits it to the electronic module assembly. The housing 1 can include a generally longitudinally extending metal barrel 12, and an end knob 13 fixed to the top end of the barrel 12 and a pressure port 11 fixed to the bottom end of the barrel 12. The pressure introduction channel 110 can be disposed in the pressure port 11. In other embodiments, the pressure introduction channel is not necessary, for example, one side of the pressure measuring element 2 can be directly exposed to the pressure medium to be measured.

[0037] The pressure measuring element 2 is disposed in the mounting cavity and sealingly connected to one end inside the pressure introduction channel 110, and electrically connected to the electronic module assembly.

[0038] The top 120 of the barrel 12 extends radially inwardly and is molded into the end knob 13. The end knob 13 has a first retaining hole 134 formed therein for retaining a grounding spring 6. The grounding spring 6 extends generally longitudinally, and its upper end is electrically connected to the top 120 and its lower end is electrically connected to the electronic module assembly.

[0039] A second retaining hole 130 can be formed in the end button 13, and the tapered portion 105 of the transition portion 103 is retained in the second retaining hole 130. Preferably, the second retaining hole 130 can be a stepped hole, which includes a first hole portion on a bottom side and a second hole portion on a top side, and a transition between the first hole portion and the second hole portion is formed by a bearing surface 133 which bears downwardly against the tapered portion 105 of the transition portion 103. The bearing surface 133 is preferably tapered, and preferably matches the outer shape of the tapered portion 105 of the transition portion 103.

[0040] At least a portion of the bottom of the tightly coiled portion 102a of the tightly coiled portion 102a is retained in the second retaining hole 130, so that the sidewall of the second hole portion laterally supports the tightly coiled portion 102a to increase the lateral stiffness of the second portion 102. Preferably, the top end of the tightly coiled portion 102a extends outside the second retaining hole 130.

[0041] The electronic module assembly can include a circuit board 24 having first electrical contact portions (not shown) disposed thereon, and the bearing surface 133 bears downwardly against the tapered portion 105 of the transition portion 103, so that the bottom end of the first portion 101 resiliently electrically contacts the first electrical contact portions.

[0042] For example, the pressure measuring element 2 can include a diaphragm 20 which generates a surface strain under the pressure, and a pressure measuring circuit 21 is disposed on the side surface of the diaphragm 20 away from the pressure port 11, and generates an electrical signal corresponding to the strain. The pressure measuring circuit 21 is electrically connected to the circuit board 24. For example, the pressure measuring circuit 21 can be electrically connected to the circuit board 24 through a flexible circuit board 23.

[0043] The shell 1 can further be provided with a substantially cylindrical support element 3, on which the circuit board 24 can be fixed, and the bottom of the support element 3 can be supported on the pressure interface 11. The inner side of one end of the pressure interface 11 longitudinally extends into the support element 3 and is provided with at least one positioning groove 113 on the periphery thereof. The inner wall of the support element 3 protrudes towards the inner side in the radial direction to form a positioning portion 314 which cooperates with the positioning groove 113. The inner side of one end of the pressure introduction channel 110 extends longitudinally towards the inside to form a connecting pipe 112. The middle of the connecting pipe 112 extends towards the outside to form a disc body 111, and a stress isolation groove 11a is left between the disc body 111 and the main body of the pressure interface 11. The diaphragm 20 is sealingly connected to the side of the disc body 111 which is away from the pressure interface 11. The edge of the disc body 111 forms a first guide groove 11b which longitudinally leaves room for the positioning portion 314. One end of the positioning portion 314 is supported on the pressure interface 11. The other end extends towards the inner side in the radial direction to form an anti-disengagement portion 313 which extends beyond the first guide groove 11b. The other end of the positioning portion 314 is close to the disc body 111. The edge of the diaphragm 20 can extend downwards to form a cylindrical extension 22, and the lower end of the extension 22 can be welded to the disc body 111. The edge of the diaphragm 20 can also be enlarged towards the outside in the radial direction to form a thickened portion 27, thereby increasing the rigidity of the edge of the diaphragm 20. The diaphragm 20 can be provided with a second guide groove 20a which corresponds to the positioning portion 314 in the circumferential direction. Correspondingly, in order to facilitate the circumferential positioning of the diaphragm 20 and the pressure interface 11 by other equipment, a window 31b which corresponds to the second guide groove 20a in the circumferential direction can be provided on the support element 3.

[0044] The bottom end of the cylindrical shell 12 can be welded to the pressure interface 11. In other schemes, the top portion 120 of the cylindrical shell 12 can also be fixed to the end knob 13 by a press-in manner, and in this case the support element 3 can provide support to the end knob 13.

[0045] The support element 3 can include a cylindrical portion 31 which extends upwards and downwards, and a plate-shaped connecting portion 32 which is integrally connected to the proximal portion near the upper end of the cylindrical portion 31 in the outer periphery. The diaphragm 20 can be enclosed inside the cylindrical portion 31, and the support element 3 can form a first room-providing portion 31a in the form of a notch or a window in the circumferential direction to allow the flexible circuit board 23 to pass through. The connecting portion 32 can also be provided with a second room-providing portion 32b in the form of a notch or a window to provide room for the flexible circuit board 23. Preferably, the first room-providing portion 31a is in the form of a notch and extends longitudinally, and the end knob 13 extends downwards to form a leg portion 131 which is cooperatively inserted into the first room-providing portion 31a downwards, thereby allowing the end knob 13 to be circumferentially positioned relative to the support element 3. The top of the support element 3 supports the edge portion of the circuit board 24 upwards.

[0046] The circuit board 24 can be a double-sided circuit board, and the lower side surface of the circuit board 24 can be provided with a processing electronic element 25 (for example, an ASIC chip), and the upper side surface of the circuit board 24 can be provided with other electronic elements 26. The upper side of the connecting portion 32 can be provided with a clearance groove 32a for providing a clearance for the processing electronic element 25. The connecting portion 32 can be upwardly protruding and formed with a plurality of hot riveting columns 32c, and the circuit board 24 can be fixed to the top end of the supporting element 3 through the hot riveting columns 32c.

[0047] It should be emphasized that the elastic terminal 10 of the utility model is not only applicable to Figure 3 the specific pressure sensor shown in the drawings, but also applicable to many known types of pressure sensors. The pressure sensor is particularly suitable for a pressure sensor built in a specific installation space in the automobile field to save the installation space, for example, a pressure sensor built in an EBS (Electronic Brake System) to obtain the pressure of a brake medium.

[0048] Please refer to Figure 7 On the basis of the first embodiment, the second portion 102 of the elastic terminal 10 can also not be collinear with the central axis of the first portion 101, for example, the central axes of the first portion 101 and the second portion 102 are laterally staggered by a certain distance. In addition to the tapered portion 105, the transition portion 103 also includes an extension portion 104 connected to the bottom end of the transition portion 103 and the top end of the first portion 101, respectively. The lateral staggered distance is mainly provided by the extension portion 104. The advantage of this is that when the area of the end button 13 available for installing the elastic terminal 10 is generally significantly smaller than the lateral area of the circuit board 24, the arrangement of the electrical contact portion can be facilitated.

[0049] At this time, the top end outer diameter of the tapered portion 105 can be smaller than the bottom end outer diameter, and the outer diameter of the first portion 101 does not have to be larger than the maximum outer diameter of the second portion 102. At least a portion of the second portion 102 can be held by a third holding hole (not shown) on an additional holding element (not shown) to avoid lateral deviation. The additional holding element can be fixed to the bottom end of the end button or fixed to the top end of the supporting element. Preferably, the tapered portion 105 and the first portion 101 partially overlap in the lateral direction, that is, the projections of the outer contours of the two on the lateral plane partially overlap, so that when the tapered portion 105 is pressed downward by the pressing surface, the first portion can be effectively compressed to elastically electrically contact the circuit board 24.

[0050] In the above embodiments, the elastic terminal 10 can also include a tapered tail portion 101a with a gradually reduced outer diameter connected to the bottom of the first portion 101.

[0051] The scope of the disclosure is not intended to be limited by the detailed description, but is instead defined by the claims and their equivalents, and all variations within the scope of the claims and their equivalents are to be construed as being included in the disclosure.

Claims

1. A pressure sensor, characterized in that, include: The housing forming an installation cavity includes end buttons (13) and pressure ports (11) located at both longitudinal ends, and a metal cylindrical shell (12) longitudinally connecting the end buttons (13) and the pressure ports (11); the pressure ports (11) have a pressure inlet channel (110) for introducing the pressure medium to be measured into the installation cavity. A pressure measuring element is disposed in the mounting cavity and sealed to one end of the pressure inlet channel (110); An electronic module assembly disposed within the mounting cavity and electrically connected to the pressure measuring element; The top (120) of the cylindrical shell (12) extends radially inward and is molded within the end button (13), which has a first retaining hole (134) for retaining a grounding spring (6); the grounding spring (6) extends longitudinally and has one end electrically contacting the top (120) and the other end electrically contacting the electronic module assembly.

2. The pressure sensor according to claim 1, characterized in that, The end button (13) has a plurality of second retaining holes (130) for retaining the spiral elastic terminal (10), the elastic terminal (10) extending longitudinally, with one end electrically contacting the electronic module assembly and the other end extending outward to the outside of the housing.

3. The pressure sensor according to claim 2, characterized in that, The elastic terminal is a helical spring, comprising: The first part, with the central axis arranged longitudinally and sparsely coiled; The second part, which is longitudinally arranged along the central axis and whose bottom end is connected to the top of the first part, includes a tightly coiled part and a sparsely coiled part whose bottom end is connected to the tightly coiled part; The transition portion connecting the top of the first portion and the bottom of the second portion includes at least one tapered portion, wherein the bottom outer diameter of the tapered portion is greater than the top outer diameter.

4. The pressure sensor according to claim 3, characterized in that, The top of the sparsely coiled portion has a transverse portion.

5. The pressure sensor according to claim 4, characterized in that, The resilient terminal also includes a tapered tail with a gradually decreasing outer diameter connected to the bottom of the first part.

6. The pressure sensor according to any one of claims 3 to 5, characterized in that, The central axis of the first part and the central axis of the second part are collinear, and the maximum outer diameter of the second part is smaller than the outer diameter of the first part.

7. The pressure sensor according to any one of claims 3 to 5, characterized in that, The central axis of the first part and the central axis of the second part are offset by a certain distance in the lateral direction.

8. The pressure sensor according to claim 7, characterized in that, The projections of the outer contours of the tapered portion and the first portion onto the transverse plane partially overlap.

9. The pressure sensor according to claim 1, characterized in that, It also includes a cylindrical support element (3) for supporting the electronic module assembly; one inner end of the pressure port (11) extends longitudinally into the support element (3) and at least one positioning groove (113) is provided on its periphery; the inner wall of the support element (3) protrudes radially inward to form a positioning part (314) that cooperates with the positioning groove (113); one inner end of the pressure inlet channel (110) extends longitudinally inward to form a connecting pipe (112), and the middle part of the connecting pipe (112) extends outward to form A disc body (111); the pressure measuring element (2) includes a metal diaphragm (20) which is hermetically connected to the side of the disc body (111) away from the pressure port (11); the edge of the disc body (111) forms a first guide groove (11b) to allow longitudinal clearance for the positioning part (314), one end of the positioning part (314) is supported on the pressure port (11), and the other end of the positioning part (314) extends radially inward beyond the first guide groove (11b).

10. The pressure sensor according to claim 9, characterized in that, The other end of the positioning part (314) approaches the disk body (111).

Images