Pressure sensor

Abstract

The invention specifically relates to a pressure sensor comprising a seat body, one end of which is provided with an inner cavity defining an opening and a pressure introduction channel extending from the other end to be communicated with the inner cavity; the pressure measuring assembly is arranged in the inner cavity; the annular electric contact element is arranged in the inner cavity, the electric contact element comprises a plurality of independent electric contact parts arranged on the inner wall or the outer wall of the electric contact element, and each electric contact part is electrically connected to the pressure measuring assembly; one end of the end button is screwed into the upper end of the opening of the inner cavity in a screw-thread fit manner; and the plurality of terminals are fixed on the end button, one end of the inner side of each terminal extends into the inner cavity, and at least in a final state in a screwing process, the inner side of each terminal is correspondingly and electrically contacted with each matched electric contact part. The device at least has the advantages of small size, compact and reasonable structure and the like.

Description

Technical Field

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

[0002] With the continuous development of semiconductor technology, micro sensors and micro sensor chips are becoming more and more popular. As one of the common sensor types, pressure sensors are widely used in automotive electronics, medical electronics, smart electrical, industrial precision equipment and other scenarios. As the size of sensors continues to decrease, heat dissipation efficiency and heat dissipation stability are crucial.

[0003] In the prior art, pressure sensors often need to be connected to internal pressure sensitive elements through terminals during component connection. Planar pressure sensitive elements usually have electrical contacts in the form of concentric rings to achieve connection between multiple terminals and pressure sensitive elements. However, such methods often result in the final pressure sensor being too large, thus limiting the application scenarios of the pressure sensor. Summary of the invention

[0004] Based on the technical problem in the prior art that terminals arranged in concentric rings easily lead to the inability to further reduce the volume of the pressure sensor, the present invention provides a pressure sensor having at least the advantages of small volume, compact structure and reasonableness.

[0005] The present invention provides a pressure sensor, comprising: a seat body, having an inner cavity with an upper end opening and a pressure introduction channel extending from the other end and communicating with the inner cavity;

[0006] A pressure measuring component disposed in the inner cavity and encapsulated at a corresponding end of the pressure introduction channel;

[0007] The electrical contact element disposed in the inner cavity comprises an annular insulating base and a plurality of electrical contact portions which are circumferentially extending in a band-like manner and are electrically isolated from each other and are disposed on the inner wall or the outer wall of the base, wherein the lower end of each of the electrical contact portions is in electrical contact with the pressure measurement assembly;

[0008] A terminal button having an internal thread formed at the lower end and screwed downwardly into the upper end opening of the inner cavity in a thread-matching manner;

[0009] A plurality of terminals are fixed on the terminal button, and an inner end of each terminal extends into the inner cavity to form a first elastic sheet, and at least in the final state during the screwing process, the first elastic sheet is in electrical contact with each of the electrical contact parts one by one.

[0010] Specifically, one of the main concepts of the present invention is to arrange the electrical contact element in close contact with the inner cavity, so that the multiple electrical contact parts are staggered in height, so that the inner cavity only needs to consider the accommodation area of ​​the pressure measuring element, and there is no need to consider the accommodation area of ​​the electrical contact element, thereby reducing the volume of the pressure sensor.

[0011] Furthermore, each of the electrical contact portions is electrically isolated by an insulating portion disposed between them;

[0012] Specifically, another concept of the present invention is to use the stacked structure of the electrical contact part as the first layer of the electrical shielding structure of the pressure measuring element, so that the electrical shielding performance of the present invention is enhanced. The electrical contact part is a wider metal element, and the insulating layer is preferably a narrow elastic plastic, sponge or other material with insulating properties to avoid mutual interference between the electrical contacts. Thus, the electrical contacts form a metal shielding layer in space to enhance the shielding performance of the present invention.

[0013] Furthermore, the electrical contact portion extends in an arc, ring or spiral shape in the circumferential direction.

[0014] Furthermore, the electrical contact portions are arranged in parallel and extend in a spiral shape in the circumferential direction.

[0015] Furthermore, the electrical contact portions are arranged in parallel and extend in a spiral shape in the circumferential direction, and their rotation direction is the same as that of the internal thread, and their spiral inclination angle is substantially equal to that of the internal thread.

[0016] In some embodiments, the electrical contact portion extends generally downward along the inner wall or outer wall surface of the base to form an extension portion, and the lower end of the extension portion passes downward over the lower end edge of the electrical contact element to form a second spring sheet, and the second spring sheet is electrically contacted to the pressure measurement component.

[0017] Furthermore, the electrical contact portion is provided with an escape fracture for making way for the extension portion corresponding to the other electrical contact portion on the upper side.

[0018] Optionally, the end button is provided with an anti-retraction protrusion at the beginning of its thread.

[0019] Optionally, the pressure measurement component includes a pressure sensitive element and a processing circuit connected to the pressure sensitive element; the pressure sensitive element is sealed in the pressure introduction channel, and the lower end of each electrical contact portion is electrically contacted to the processing circuit.

[0020] Optionally, sealant may be applied to the connection between the terminal button and the seat body.

[0021] Furthermore, the pressure measurement component includes a substrate, which is packaged at a corresponding end of the pressure introduction channel. A pressure sensitive element and a processing circuit are provided on the side of the substrate away from the pressure introduction channel. The processing circuit is electrically connected to the pressure sensitive element and electrically contacted to the lower end of the electrical contact portion.

[0022] Furthermore, a substrate sealing ring is provided between the base and the seat body.

[0023] In summary, the present invention provides a pressure sensor having at least the following advantages:

[0024] 1. The electrical contact element is arranged in close contact with the inner cavity, so that the plurality of electrical contact parts are staggered in height, so that the inner cavity only needs to consider the accommodation area of ​​the pressure measuring element, and does not need to consider the accommodation area of ​​the electrical contact element, thereby reducing the volume of the pressure sensor;

[0025] 2. The laminated structure of the electrical contact part enables it to be used as the first layer of electrical shielding structure of the pressure measuring element, so that the electrical shielding performance of the present invention is enhanced. The electrical contact part is a wider metal element, and the insulating layer is preferably a narrower elastic plastic, sponge or other material with insulating properties to avoid mutual interference between the electrical contacts. Thus, the electrical contacts form a metal shielding layer in space. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention will be further described in detail below in conjunction with the accompanying drawings and preferred embodiments, but those skilled in the art will appreciate that these drawings are drawn only for the purpose of explaining the preferred embodiments and therefore should not be used as a limitation on the scope of the present invention. In addition, unless otherwise specified, the drawings are only schematically representing the composition or structure of the described objects and may contain exaggerated displays, and the drawings are not necessarily drawn to scale.

[0027] Figure 1 A cross-sectional schematic diagram of a pressure sensor provided by an embodiment of the present invention;

[0028] Figure 2 A schematic cross-sectional view of a pressure sensor in another direction provided by another embodiment of the present invention;

[0029] Figure 3 A partial schematic diagram of an electrical contact element provided by an embodiment of the present invention;

[0030] 1. seat; 2. pressure measuring assembly; 3. terminal; 11. inner cavity; 12. pressure introduction channel; 13. electrical contact element; 14. pressure connector; 21. pressure sensitive element; 22. processing circuit; 23. substrate; 24. lead; 25. frame; 26. protective gel; 31. first terminal; 32. second terminal; 33. third terminal; 34. thread; 35. positioning step; 131. first electrical contact part; 132. second electrical contact part; 133. third electrical contact part; 134. insulating base; 135. avoidance fracture; 14a. pressure sealing ring; 23a. substrate sealing ring; 31a-33a. first spring piece; 34a. internal thread; 34b. external thread; 35a. connection; 131a-133a. second spring piece; 134a. insulating part. DETAILED DESCRIPTION

[0031] The following is combined with Figures 1 to 3 , the present invention is described in detail.

[0032] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0033] It is worth noting that the embodiments of the present invention use ordinal numbers such as "first" and "second" to distinguish multiple objects, and are not used to limit the order, timing, priority or importance of multiple objects. For example, the first spring clips 31a~33a and the second spring clips 131a~133a are only for the convenience of description, and do not indicate the difference in the order, importance, etc. of the first spring clips 31a~33a and the second spring clips 131a~133a. In addition, the term "connection" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, a conflicting connection or an integrated connection; wherein, "connection" can also be a direct connection or an indirect connection. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] In order to explain the technical solution provided by the present invention, please refer to Figure 1 Shown is a cross-sectional schematic diagram of a pressure sensor provided by an embodiment of the present invention.

[0035] Specifically, the pressure sensor provided by the present invention includes a seat body 1, a pressure measuring element and a terminal 3. Among them, one end of the seat body 1 is provided with an inner cavity 11 with an upper opening (not marked) to accommodate the pressure measuring component 2; and the other end of the seat body 1 is provided with a pressure introduction channel 12, one end of the pressure introduction channel 12 is connected to the inner cavity 11 from the lower end of the seat body 1, and the other end of the pressure introduction channel 12 is used to introduce the pressure medium to be measured. The pressure measuring component 2 is sealed to the inner end of the pressure introduction channel 12 (i.e., the upper end in the figure) to measure the pressure of the pressure medium to be measured introduced by the pressure introduction channel 12. Among them, the pressure introduction channel 12 can be formed inside a pressure joint 14, and the above-mentioned pressure joint 14 can be extended downward from the lower end of the seat body 1.

[0036] The lower end of the end button 3 and the upper end opening of the seat body 1 are provided with threads, and the end button 3 can be screwed to the upper end opening of the seat body 1 by means of threaded connection. Compared with the prior art, the end button is usually connected to the seat body by riveting or bonding. The above connection method can provide downward pressing force compared with the bonding method, and at the same time avoids the disadvantage that the riveting method requires the seat body to have at least a metal thin shell-shaped cylinder. Specifically, the lower end of the end button 3 is provided with an internal thread 34a, and the upper end opening of the inner cavity 11 is provided with an external thread 34b in cooperation therewith.

[0037] The pressure sensor further includes an electrical contact element 13 disposed in the inner cavity 11. The electrical contact element 13 includes an annular insulating base 134 and three mutually isolated (insulated) electrical contacts fixedly disposed on the inner wall or outer wall of the insulating base 134, including a first electrical contact 131, a second electrical contact 132, and a third electrical contact 133. Each electrical contact 131-133 is electrically connected to the pressure measurement assembly 2.

[0038] A plurality of terminals are fixed on the terminal button 3, for example, the first terminal 31, the second terminal 32 and the third terminal 33. The inner ends of the plurality of terminals 31-33 (i.e., the lower ends in the figure) extend into the inner cavity 11, and the inner ends of the terminals 31-33 can form first spring pieces 31a-33a respectively. When the terminal button 3 is screwed into the final state, each spring piece 31a-33a is electrically contacted to the first electrical contact part 131, the second electrical contact part 132 and the third electrical contact part 133 one by one. In some other schemes, the number of terminals and electrical contacts can also be set to four or other numbers according to the needs of signal processing. Among them, the above-mentioned final state (or the final angle / height position of the terminal button 2 relative to the seat body 1) can be defined by a positioning step 35 formed by the proximal end of the lower end of the terminal button 3 protruding outward and the upper end of the seat body 1, or by the mating end point of the thread.

[0039] The lower ends of the electrical contacts 131 - 133 are electrically connected to the pressure measurement assembly 2 .

[0040] The advantage of the present invention is that the terminal button can be conveniently connected to the main housing by threaded connection, and can be electrically connected to the pressure measurement component by electrical contact through the annular electrical contact element. The connection 35a between the terminal button 3 and the seat body 1 can be provided with a sealant, or an elastic sealing pad can be provided between the positioning step 35 and the corresponding end surface of the seat body 1, so as to enhance the sealing performance.

[0041] For example only, the pressure measurement component 2 may include a substrate 23. The substrate 23 is sealed and connected to the inner end of the pressure introduction channel 12. For example, the peripheral portion of the pressure introduction channel 12 facing the pressure measurement component 2 may form a pressure seal with the substrate 23 through a substrate sealing ring 23a. The pressing force of the pressure seal may be provided by the threaded connection, that is, the lower end of the terminal button 3 may be pressed downward against the upper end of the insulating base 134, and the lower end of the insulating base 134 presses the substrate 23 downward to the substrate sealing ring 23a. In some other schemes, the lower end of the substrate 23 may also be directly sealed to the peripheral portion of the pressure introduction channel 12 facing the pressure measurement component 2 by glue.

[0042] A pressure sensitive element 21 and a processing circuit 22 may be disposed on the upper side of the substrate 23, and the pressure sensitive element 21 may be electrically connected to the processing circuit 22 via a lead 24. The processing circuit 22 may include a plurality of electrical contact pads (not shown), and the lower ends of the electrical contact portions 131 to 133 may be electrically contacted to the electrical contact pads correspondingly.

[0043] Preferably, the plurality of electrical contacts 131 to 133 extend in a band shape on the circumference of the inner wall or outer wall of the insulating base 134. Specifically, the plurality of electrical contacts 131 to 133 may extend in a complete ring shape on the inner wall or outer wall of the insulating base 134, or may be only a portion of the ring shape, such as an arc shape. In this embodiment, preferably, the electrical contacts 131 to 133 may extend in a spiral shape on the inner wall or outer wall of the insulating base 134 (such as Figures 1-2 As shown), the first spring pieces 31a-33a can maintain electrical contact at more angles when the end button 3 is screwed into the upper opening of the seat body 1. For example, when the end button 3 is screwed into the upper opening of the seat body 1 for three turns by means of a threaded connection, the electrical contact parts 131-133 are spirally extended from the corresponding position to the starting point for at least three turns, so that it can be ensured that the first spring pieces 31-33 can form electrical contact with the corresponding electrical contact parts 131-133 in the entire screwed-in state. It is easy to understand that the direction of rotation of the spirally extended electrical contact parts 131-133 should be the same as that of the internal thread 34a, and the spiral inclination angle thereof should be substantially equal to the thread inclination angle of the internal thread 34a.

[0044] As attached Figures 1-2As shown, the electrical contact portions 131-133 can extend side by side and can overlap in height. In some other solutions, the electrical contact portions 131-133 can also be at completely different heights, that is, the electrical contact portions 131-133 have no overlap in height, that is, in this case, it is only necessary to increase the lower end spacing of the first spring pieces 31a-33a of the terminals 31-33 accordingly.

[0045] Preferably, the pressure measurement component 2 is further provided with a frame 25 on the upper side of the substrate 23 and enclosing the pressure sensitive element 21 inside. The frame 25 may be filled with a protective gel 26 covering the pressure sensitive element 21 and the lead wires 24 .

[0046] An insulating portion 134a is provided between each electrical contact portion, and the ratio of the axial width of the insulating portion 134a to the axial width of the electrical contact portion can be set to 1:1.5 to 3. Each electrical contact portion is a conductor and is arranged around the pressure measurement component 2, so it can also form a certain electromagnetic shielding protection for the pressure measurement component 2.

[0047] Optionally, each terminal 31-33 is provided with a bent first spring sheet 31a-33a at the end thereof (see Figure 2 The figure shows a cross-sectional schematic diagram of another direction of a pressure sensor provided by another embodiment of the present invention. The ends of the first spring pieces 31a~33a are provided with widened contact blocks according to the first electrical contact portion 131, the second electrical contact portion 132, and the third electrical contact portion 133. After the terminal button 3 is completely screwed in, each contact block is respectively connected to the first electrical contact portion 131, the second electrical contact portion 132, and the third electrical contact portion 133.

[0048] Optionally, 2-3 turns of thread are provided at the end of the terminal button 3. Considering the contact reliability between the contact block and each annular contact part, the number of turns of thread 34 of the terminal button 3 should be designed to be small enough to avoid each terminal from contacting other parts of the inner wall for a long time during the rotation process, which would damage the contact reliability of the terminal.

[0049] Preferably, the first electrical contact portion 131, the second electrical contact portion 132, and the third electrical contact portion 133 are electrically connected to the pressure measurement component 2 through the second elastic pieces 131a-133a. Since each electrical contact portion is arranged above the pressure measurement component 2 through a height space, in order to solve the problem of electrical contact between each electrical contact portion and the pressure measurement component 2, each electrical contact portion 131-133 extends approximately downward along the inner wall or outer wall surface of the base 134 to form an extension portion (not marked), and the lower end of the extension portion passes downward over the lower end edge of the electrical contact element to form the above-mentioned second elastic piece 131a-133a, and each electrical contact portion 131-133 is connected to the pressure measurement component 2 through the connection of the second elastic pieces 131a-133a. For example, two avoidance breaks 135 are provided on the third electrical contact portion 133 at the lower side, so as to make room for the extensions of the first electrical contact portion 131 and the second electrical contact portion 132 at the upper side, and one avoidance break 135 is provided on the second electrical contact portion 132, so as to make room for the extension of the first electrical contact portion 131 at the upper side. These avoidance breaks 135 are staggered with each other in the circumferential direction.

[0050] The present invention is described in detail above. The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the present invention and its core ideas. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, the present invention can also be improved and modified in a number of ways, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A pressure sensor, characterized in that: include: The seat body (1) has an inner cavity (11) with an upper end opening and a pressure introduction channel (12) extending from the other end and connected to the inner cavity (11); A pressure measuring component (2) disposed in the inner cavity (11) and sealed to a corresponding end of the pressure introduction channel (12); An electrical contact element (13) disposed in the inner cavity (11), comprising an annular insulating base (134) and a plurality of electrical contact portions (131-133) which are electrically isolated from each other and are disposed on the inner wall or the outer wall of the base in a band-like manner and extending in the circumferential direction, wherein the lower end of each of the electrical contact portions (131-133) is electrically in contact with the pressure measurement component (2); An end button (3) having an internal thread (34a) formed at the lower end and screwed downwardly into the upper end opening of the inner cavity (11) in a threaded manner; A plurality of terminals (31-33) are fixed on the terminal button (3), an inner end of each terminal (31-33) extends into the inner cavity (11) and forms a first spring sheet (31a-33a), and at least in the final state during the screwing process, the first spring sheet (31a-33a) is in electrical contact with each electrical contact portion one by one.

2. A pressure sensor as claimed in claim 1, characterized in that: The electrical contact portions (131-133) are electrically isolated by an insulating portion (134a) provided between them.

3. A pressure sensor as claimed in claim 2, characterized in that: The electrical contact portions (131-133) extend in an arc, ring or spiral shape in the circumferential direction.

4. A pressure sensor as claimed in claim 1, characterized in that: The electrical contact portions (131-133) respectively extend approximately downward along the inner wall or outer wall surface of the base to form an extension portion, the lower end of the extension portion passes downward over the lower end edge of the electrical contact element (13) to form a second spring piece (131a-133a), and the second spring piece (131a-133a) is in electrical contact with the pressure measurement component (2).

5. A pressure sensor as claimed in claim 4, characterized in that: The electrical contact parts (131-133) are provided with avoidance fractures (135) for giving way to extension parts corresponding to other electrical contact parts on the upper side.

6. A pressure sensor as claimed in claim 1, characterized in that: The end button (3) is provided with an anti-retraction protrusion at the beginning of its thread.

7. A pressure sensor as claimed in claim 1, characterized in that: The pressure measurement assembly (2) comprises a pressure sensitive element (21) and a processing circuit (22) connected to the pressure sensitive element (21); the pressure sensitive element (21) is sealed in the pressure introduction channel (12), and the lower end of each of the electrical contact portions (131-133) is in electrical contact with the processing circuit (22).

8. A pressure sensor as claimed in claim 1, characterized in that: Sealant may be applied to the connection between the terminal button (3) and the seat body (1).

9. A pressure sensor as claimed in claim 8, characterized in that: The pressure measurement assembly (2) comprises a substrate (23), the substrate (23) being sealed to a corresponding end of the pressure introduction channel (12), a pressure sensitive element (21) and a processing circuit (22) being provided on a side of the substrate 23 away from the pressure introduction channel (12), the processing circuit (22) being electrically connected to the pressure sensitive element (21) and electrically contacting the lower end of the electrical contact portion (131-133).

10. A pressure sensor as claimed in claim 9, characterized in that: A substrate sealing ring (23a) is provided between the substrate (23) and the base body (1).

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