CN118837025A - Pressure sensor - Google Patents

Abstract

A pressure sensor, comprising: a housing enclosing a mounting cavity, provided with a pressure introduction passage having one end of the inner side thereof connected to the mounting cavity; a pressure sensitive element positioned in the mounting cavity and sealed and fixed at one end of the inner side of the pressure introducing channel; a supporting seat positioned in the mounting cavity and the lower end of which is fixed to the inner side of the shell, wherein the supporting seat is provided with a containing hole for containing the pressure sensitive element; the first circuit board is fixed on the upper side of the supporting seat and is electrically connected to the pressure sensitive element; the second circuit board is fixed on the lower side of the supporting seat and is provided with a through hole for allowing the pressure sensitive element to pass up and down; and a plurality of electric contact springs, which are electrically contacted to the first circuit board and the second circuit board in a one-to-one correspondence manner, are held on the supporting seat. According to the pressure sensor, the two circuit boards are respectively arranged on the upper side and the lower side of the supporting seat and are electrically connected through the electric contact springs, so that the cost is reduced, and meanwhile, the assembly is facilitated.

Description

Pressure Sensors

Technical Field

The present application relates to the field of sensor technology, and in particular to a pressure sensor.

Background Art

In a pressure sensor for measuring hydraulic pressure, a dual circuit board is usually provided to maintain a small size (especially the lateral size), wherein the first circuit board is connected to the pressure sensitive element, and the other circuit board is electrically connected to the first circuit board through a flexible circuit board, and needs to be mechanically fixed to the terminal in advance. Therefore, the flexible circuit board raises the overall cost of the product due to its relatively high price, and is also not conducive to assembly. For example, the movement and assembly of the terminal are limited by the length of the flexible board.

Summary of the invention

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

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

A housing enclosing a mounting cavity, wherein a pressure introduction passage is provided at one inner end thereof and connected to the mounting cavity;

A pressure sensitive element located in the installation cavity and sealed and fixed to one end of the inner side of the pressure introduction channel;

A support seat located in the installation cavity and fixed at its lower end to the inner side of the housing, and provided with an accommodating hole for accommodating the pressure sensitive element;

A first circuit board fixed to the upper side of the support base, electrically connected to the pressure sensitive element;

A second circuit board fixed to the lower side of the support base, having a through hole for allowing the pressure sensitive element to pass up and down;

A plurality of electrical contact springs, whose upper and lower ends are electrically contacted to the first circuit board and the second circuit board in a one-to-one correspondence, are held on the support seat.

The pressure sensor is constructed by arranging two circuit boards on the upper and lower sides of the support seat respectively and electrically connecting them through electrical contact springs, thereby reducing costs and facilitating assembly.

In order not to hinder the connection with the outer shell and to maintain an appropriate height between the two circuit boards, preferably, the support seat includes a retaining portion, an upper support portion arranged at the upper end of the retaining portion, and a lower support portion formed by the edge of the retaining portion protruding downward, and a concave cavity is formed between the lower side surface of the retaining portion and the inner wall of the lower support portion, and the second circuit board is fixed in the concave cavity.

Preferably, the second circuit board is bonded to the lower surface of the holding portion.

Alternatively, preferably, the edge of the second circuit board is snapped onto the inner wall of the lower support portion.

In order to facilitate the assembly of the first circuit board, preferably, the first circuit board is clamped on the upper side of the support seat.

In order to facilitate the assembly of the first circuit board, preferably, the upper support portion is arranged at the upper end edge of the holding portion and a plurality of buckles are formed thereon, and the first circuit board is fixed to the upper side surface of the holding portion by the buckles.

Preferably, the holding portion is provided with a plurality of first holding holes penetrating vertically and holding the electric contact spring in a vertical posture.

Preferably, the shell includes a metal cylinder shell, a terminal button connected to the upper end of the cylinder shell and a metal pressure port connected to the lower end of the cylinder shell; the lower support portion is snapped into the pressure port; the lower end of the cylinder shell is welded to the pressure port, and the upper end presses the terminal button downward to the upper support portion.

Preferably, the pressure sensor further comprises a terminal, the upper end of the terminal extends to the outside of the housing, and the lower end of the terminal extends into the interior of the housing to be electrically connected to the first circuit board.

Preferably, the terminal button is provided with a plurality of second retaining holes extending vertically therethrough, and the terminal includes a stepped spring, which is retained in the second retaining hole; the upper end of the stepped spring extends outward to the outside of the housing and the lower end electrically contacts the first electrical contact portion provided on the upper surface of the first circuit board.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic structural diagram of a pressure sensor according to a preferred embodiment.

FIG. 2 is a schematic structural diagram of a pressure sensor according to another preferred embodiment.

Explanation of the reference numerals: 10, pressure introduction channel; 11a, expanded diameter portion; 11b, groove; 11, protrusion; 1, pressure port; 2, cylinder shell; 31, support portion; 32, membrane; 33, pressure measurement circuit; 34, thickened portion; 3, pressure sensitive element; 42, lower support portion; 43a, buckle; 43, upper support portion; 44a, upper side surface; 44b, lower side surface; 44, retaining portion; 45, pressing edge; 49a, first retaining hole; 49, electrical contact spring; 4a, accommodating hole; 4, support seat; 5a, via hole; 5, second circuit board; 61, electronic component; 62, lead; 6a, via hole; 6, first circuit board; 71, lower end; 7a, step surface; 7b, second retaining hole; 7c, sealing ring; 7, terminal button; 8, terminal.

DETAILED DESCRIPTION

The technical solution of the present application will be clearly and completely described below in conjunction with the accompanying drawings. The following embodiments are exemplary and are only used to explain the present application, and cannot be interpreted as limiting the present application. In the following description, the same symbols are used to represent the same or equivalent elements, and repeated descriptions are omitted.

In the description of the present application, it should be understood that the terms "upper", "lower", "inside", "outside", "left", "right", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the products of the present application are conventionally placed when in use, or are the orientations or positional relationships conventionally understood by those skilled in the art. They are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

In addition, the terms "installed", "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

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

As shown in FIG1 , a pressure sensor according to a preferred embodiment of the present invention comprises a housing and a pressure sensitive element 3, a support seat 4, a second circuit board 5 and a first circuit board 6 arranged in a mounting cavity (not marked) surrounded by the housing. The housing has a pressure introduction channel 10 for introducing the pressure medium to be measured into the mounting cavity. The inner end of the pressure introduction channel 10 is connected to the mounting cavity. The pressure sensitive element 3 may include a horizontally extending metal membrane 32, and a pressure measurement circuit 33 is arranged on the upper surface of the membrane 32, such as a Wheatstone bridge composed of a plurality of piezoresistors; the edge of the membrane 32 extends downward to form a circle of support portion 31, and the lower end of the support portion 31 can be sealed and fixedly connected to the pressure port 1. In some other embodiments, the pressure sensitive element 3 may also be some other types of pressure sensitive elements, such as a capacitive pressure sensitive element, or a semiconductor pressure sensitive element in terms of material.

Merely by way of example, the housing includes a metal shell 2, a terminal 7 connected to the upper end of the shell 2, and a metal pressure port 1 connected to the lower end of the shell 2. The pressure port 1 is preferably made of metal so that it can be welded to the lower end of the support portion 31. By way of example, the upper end of the pressure introduction channel 10 is defined by a tubular protrusion 11 formed by the upper end of the pressure port 1 protruding upward. The middle portion of the outer wall of the protrusion 11 can be expanded outward to form a circle of expanded diameter portion 11a. The lower end of the support portion 31 can be supported and welded to the expanded diameter portion 11a. Accordingly, a circle of grooves 11b is formed between the expanded diameter portion 11a and the upper side surface of the pressure port 1 to reduce the influence of the installation stress of the pressure port 1 on the pressure sensitive element 3.

The support seat 4 is fixed in the installation cavity, and includes a retaining portion 44, an upper support portion 43 arranged at the upper end of the retaining portion 44, and a lower support portion 42 formed by the edge of the retaining portion protruding downward. A concave cavity (not marked) is surrounded by the lower side surface 44b of the retaining portion 44 and the inner wall of the lower support portion 42. The second circuit board 5 is fixed in the concave cavity. Specifically, the second circuit board 5 is bonded to the lower side surface 44b of the retaining portion 44, or the edge of the second circuit board 5 is tightly fitted to the inner wall of the lower support portion 42 or is snapped to the inner wall of the lower support portion 42. The first circuit board 6 can be bonded to the upper side surface 44a of the retaining portion 44, and can be additionally snapped and fixed by a plurality of buckles 43a formed on the upper support portion 43.

The lower support portion 42 can be snapped onto an inner annular positioning step formed on the pressure port 1. The lower end of the cylinder shell 2 is welded to an outer annular positioning step formed on the pressure port 1, and the upper end of the cylinder shell 2 can be rolled inward to form a circle of pressing edge 45, and the pressing edge 45 is pressed downward to an upward circle of step surface 7a formed on the outer wall of the terminal button 7, so that the pressing edge 45 presses the lower end 71 of the terminal button 7 to the upper support portion 43. A sealing ring 7c can be arranged between the pressing edge 45 and the step surface 7a. A sealant can also be additionally applied to the gap between the pressing edge 45 and the outer wall of the terminal button 7.

In order to facilitate the electrical connection between the pressure sensitive element 3 and the first circuit board 6, a receiving hole 4a for receiving the pressure sensitive element 3 is provided on the holding portion 44, and the receiving hole 4a passes through the holding portion 44 from top to bottom. The pressure measurement circuit 33 of the pressure sensitive element 3 is electrically connected to the processing circuit including a plurality of electronic components 61 provided on the upper surface of the first circuit board 6 through the lead 62. The first circuit board 6 may be provided with a via 6a that allows the lead 62 to pass up and down. The second circuit board 5 is also provided with a via 5a that allows the protrusion 11 to pass up and down. The holding portion 44 is provided with a plurality of first retaining holes 49a that pass through from top to bottom, and the electrical contact spring 49 is provided in the first retaining hole 49a and is maintained in a vertical posture. The upper and lower ends of the electrical contact spring 49 are electrically contacted to the first circuit board 6 and the second circuit board 5 in a one-to-one correspondence. During assembly, the second circuit board 5 can be temporarily placed on the upper surface of the pressure port 1, and then the pressure sensitive element 3 can be welded to the protrusion 11, and then the second circuit board 5 can be lifted (without being separated from the pressure sensitive element 3, and the outer diameter of the pressure sensitive element 3 is preferably larger than the inner diameter of the second via 5a to increase the available area of the second circuit board 5) and installed on the support seat 4.

The upper end of the support portion 31 can be expanded outward to form a thickened portion, thereby increasing the rigidity of the edge of the membrane 32 . At the same time, it also requires a larger receiving hole 4 a, but also limits the assembly method of the second circuit board 5 accordingly.

In some other embodiments, the pressure sensor further includes a plurality of terminals 8. The upper ends of the terminals 8 extend to the outside of the housing. The lower ends of the terminals 8 extend into the interior of the housing and are electrically connected to the first circuit board 6. Preferably, the terminal 7 is provided with a plurality of second retaining holes 7b extending vertically. The terminal 8 includes a stepped spring. The stepped spring is retained in the second retaining hole 7b. The upper end of the stepped spring extends outward to the outside of the housing and the lower end electrically contacts the first electrical contact portion provided on the upper surface of the first circuit board 6.

Please refer to Figure 2. In another preferred embodiment, preferably, the lower surface of the second circuit board 5 can also be directly bonded to the upper surface of the pressure port 1. In this case, when assembling the pressure sensor, the second circuit board 5 can be bonded to the upper surface of the pressure port 1 first, and then the pressure sensitive element 3 can be welded to the protrusion 11, and then the support base 4 and the first circuit board 6 can be assembled to the pressure port 1.

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 (10)

1. A pressure sensor, comprising: A housing enclosing a mounting cavity, wherein a pressure introduction channel (10) is provided on the housing, one inner end of the pressure introduction channel being connected to the mounting cavity; A pressure sensitive element (3) located in the installation cavity and sealed and fixed to one end of the inner side of the pressure introduction channel (10); A support seat (4) located in the installation cavity and having its lower end fixed to the inner side of the housing, and having a receiving hole (4a) for receiving the pressure sensitive element (3); A first circuit board (6) fixed to the upper side of the support seat (4) and electrically connected to the pressure sensitive element (3); A second circuit board (5) fixed to the lower side of the support seat (4), provided with a through hole (5a) for allowing the pressure sensitive element (3) to pass up and down; A plurality of electrical contact springs (49) are electrically contacted to the first circuit board (6) and the second circuit board (5) in a one-to-one correspondence at the upper and lower ends and are held on the support seat (4). 2. The pressure sensor according to claim 1 is characterized in that the support seat (4) includes a retaining portion (44), an upper support portion (43) arranged at the upper end of the retaining portion (44), and a lower support portion (42) formed by the edge of the retaining portion protruding downward, and a concave cavity is formed between the lower side surface (44b) of the retaining portion (44) and the inner wall of the lower support portion (42), and the second circuit board (5) is fixed in the concave cavity. 3. The pressure sensor according to claim 2, characterized in that the second circuit board (5) is bonded to the lower surface (44b) of the holding portion (44). 4. The pressure sensor according to claim 2, characterized in that an edge of the second circuit board (5) is clamped onto an inner wall of the lower support portion (42). 5. The pressure sensor according to claim 2, characterized in that the first circuit board (6) is clamped on the upper side of the support seat (4). 6. The pressure sensor according to claim 3 is characterized in that the upper support portion (43) is arranged at the upper end edge of the retaining portion (44) and has a plurality of clips (43a) formed thereon, and the first circuit board (6) is fixed to the upper side surface (44a) of the retaining portion (44) by the clips (43a). 7. The pressure sensor according to claim 1, characterized in that the holding portion (44) is provided with a plurality of first holding holes (49a) penetrating vertically and holding the electrical contact spring (49) in a vertical posture. 8. The pressure sensor according to any one of claims 2 to 7 is characterized in that the shell comprises a metal cylindrical shell (2), a terminal button (7) connected to the upper end of the cylindrical shell (2) and a metal pressure port (1) connected to the lower end of the cylindrical shell (2); the lower support portion (42) is snapped into the pressure port (1); the lower end of the cylindrical shell (2) is welded to the pressure port (1), and the upper end presses the terminal button (7) downward to the upper support portion (43). 9. The pressure sensor according to claim 8 is characterized in that it also includes a terminal, wherein the upper end of the terminal (8) extends to the outside of the housing, and the lower end of the terminal (8) extends into the interior of the housing to be electrically connected to the first circuit board (6). 10. The pressure sensor according to claim 9 is characterized in that a plurality of second retaining holes (7b) extending vertically therethrough are provided on the terminal button (7), and the terminal comprises a stepped spring, which is retained in the second retaining hole (7b); the upper end of the stepped spring extends outward to the outside of the housing and the lower end electrically contacts the first electrical contact portion provided on the upper surface of the first circuit board (6).