Pressure sensor

Abstract

The utility model provides a pressure sensor, and relates to the technical field of sensors, and the pressure sensor comprises a housing which is provided with an inner cavity; one end of the pressure sensing base is fixedly connected with one end of the shell; the support is arranged in the inner cavity, and one end of the support is fixedly connected with the other end of the pressure sensing base; one end of the first circuit board is fixedly connected with the other end of the bracket; one end of the first plastic part is fixedly connected with the other end of the bracket; a plurality of limiting holes are formed in the second plastic part; the elastic pieces are at least partially located in the limiting holes; the pressure sensor comprises a first plastic part and a second circuit board, the two sides of the first plastic part are coated with the second circuit board, the two sides of the second circuit board are electrically connected with the elastic part and the first circuit board respectively, and the structural applicability of the sensor is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of sensors, in particular to a pressure sensor. Background Art

[0002] The electronic stability control system (ESC) is a vehicle body stability system. When the vehicle body is in a critical out-of-control state, the ESC system can intervene to control the braking force and speed of the four wheels to return the vehicle body to a stable state. The high-pressure pressure sensor can be used to provide the ESC system with the oil pressure of the brake oil circuit.

[0003] In order to reduce the space occupied by the pressure sensor in the hydraulic brake system, most existing pressure sensors use a spring that is squeezed from the side (two plastic parts are used to fix and press the spring) or a conductive pin that provides a step surface as the bottom support surface of the spring and is crimped with another L-shaped conductive pin, thereby achieving electrical connection between the PCB board and the spring. The existing solution requires a relatively close distance between the spring and the circuit board, so the position design of the spring is limited and cannot meet all customers' specific requirements for the spring position. In addition, the existing solution cannot achieve effective electrical connection for products with 4 springs due to insufficient available space on the circuit board. Utility Model Content

[0004] The purpose of the utility model is to overcome the defects of the prior art and provide a pressure sensor to meet the design requirements of the specific structure of the pressure sensor product and improve the structural applicability of the pressure sensor.

[0005] In order to achieve the above objectives and other objectives, the present invention is implemented by including the following technical solutions: The present invention provides a pressure sensor, the pressure sensor comprising:

[0006] A shell, the shell having an inner cavity; a pressure-sensitive base, one end of the pressure-sensitive base is fixedly connected to one end of the shell, and the pressure-sensitive base has a pressure-sensitive channel; a bracket is arranged in the inner cavity, one end of the bracket is fixedly connected to the other end of the pressure-sensitive base; a first circuit board, the first circuit board is arranged in the inner cavity, one end of the first circuit board is fixedly connected to the other end of the bracket, and the first circuit board and the pressure-sensitive base are electrically connected; a first plastic part is arranged in the inner cavity, one end of the first plastic part is fixedly connected to the other end of the bracket; a second plastic part, one end of the second plastic part is fixedly connected to the other end of the shell, and a plurality of limiting holes are arranged in the second plastic part; a plurality of elastic parts are matched with the plurality of limiting holes, respectively, and the elastic parts are at least partially located in the limiting holes;

[0007] And a second circuit board is arranged in the inner cavity, the second circuit board is covered on both sides of the first plastic member, and the two sides of the second circuit board are electrically connected to the elastic member and the first circuit board respectively.

[0008] In some embodiments, the first circuit board is a rigid circuit board, and the second circuit board is a flexible circuit board.

[0009] In some embodiments, the second circuit board has a plurality of contact points electrically connected to the plurality of elastic members respectively.

[0010] In some embodiments, the second circuit board is bonded to both sides of the first plastic member.

[0011] In some embodiments, the pressure-sensitive base includes a pressure-sensitive head with a top and a pressure-sensitive chip disposed on an outer side wall of the pressure-sensitive head, and the pressure-sensitive chip is electrically connected to the first circuit board.

[0012] In some embodiments, the pressure sensing head is located in the bracket, and the first circuit board is located between the pressure sensing head and the first plastic component and is disposed in the bracket.

[0013] In some embodiments, the bracket and the first plastic part are integrally injection-molded, and the shell and the second plastic part are integrally injection-molded.

[0014] In some embodiments, the elastic member is a coil spring, and the number of the coil springs is less than or equal to 4.

[0015] In some embodiments, the elastic member includes a variable pitch section in the middle and a top conical section and a bottom conical section at both ends, and the diameters of the top conical section and the bottom conical section gradually decrease in the direction outward from the limiting hole.

[0016] In some embodiments, the limiting hole has a tapered structure at the top tapered section.

[0017] The utility model provides a pressure sensor. Compared with the prior art, the utility model has the following beneficial effects: the pressure sensor provides a large stable contact plane for a spring through a flexible second circuit board (FPC) bonded to a first plastic part, and electrical connection is achieved through crimping with the spring through four contact points on the second circuit board. The spring is pressed on the plane, which is conducive to ensuring the position accuracy of the spring and the reliability of the spring crimping.

[0018] Compared with the existing technology, by adjusting the position and number of circular contact points on the second circuit board, the design requirements of the client can be met, the application scenarios of the product are increased, and the second circuit board is only responsible for providing copper leakage contact points for the spring, which greatly improves the space utilization of the first circuit board (PCB) and solves the problem of insufficient space. The second circuit board FPC and the first circuit board PCB extend from the upper end as a soft-hard combination board, and the second circuit board is bonded to the circular first plastic part, which has a good supporting effect on the second circuit board. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Shown is a schematic structural diagram of the pressure sensor of the utility model.

[0020] Figure 2 Shown is a cross-sectional view of the pressure sensor of the present invention.

[0021] Figure 3 Shown is a schematic diagram of the internal structure of the pressure sensor of the utility model.

[0022] Figure 4 Shown is an exploded view of the pressure sensor of the present invention.

[0023] Numbers in the figure:

[0024] 1-shell, 11-inner cavity;

[0025] 2-pressure sensing base, 21-pressure sensing channel, 22-pressure sensing head, 23-pressure sensing chip;

[0026] 3- bracket, 31- fixed foot, 32- port;

[0027] 4- first circuit board;

[0028] 5-first plastic part;

[0029] 6-second circuit board, 61-contact point;

[0030] 7-elastic member, 71-variable pitch section, 72-top tapered section, 73-bottom tapered section;

[0031] 8-second plastic part, 81-limiting hole, 81a-conical structure. DETAILED DESCRIPTION

[0032] See also Figures 1 to 4The following describes the implementation of the present invention through specific examples. Those skilled in the art can easily understand other advantages and functions of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific implementations, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0033] like Figure 1 and Figure 2 As shown, the utility model provides a pressure sensor, which includes a shell 1 , which is a metal shell and has an inner cavity 11 .

[0034] like Figure 2 As shown, the pressure sensor includes a pressure-sensitive base 2, and the pressure-sensitive base 2 can be a metal base. One end of the pressure-sensitive base 2 is fixedly connected to one end of the shell 1. Specifically, the bottom of the shell 1 is fixedly connected to the outer edge of the middle step surface of the pressure-sensitive base 2, and the fixing can be welding. The pressure-sensitive base 2 has a pressure-sensitive channel 21, and the pressure-sensitive medium can enter from the pressure-sensitive channel 21. The pressure-sensitive base 2 includes a pressure-sensitive head 22 at the top and a pressure-sensitive chip 23 arranged on the outer side wall of the pressure-sensitive head 22. The pressure-sensitive chip 23 can output a pressure signal through the piezoresistance principle. For example, the stainless steel elastic diaphragm on the pressure-sensitive head 22 is deformed after sensing the pressure transmitted by the medium in the pressure-sensitive channel 21, causing the resistance on the pressure-sensitive chip 23 to change, thereby outputting an electrical signal.

[0035] like Figure 4 As shown, the pressure sensor includes a bracket 3, which is arranged in the inner cavity 11. The bottom of the bracket 3 can be fixedly connected to the inner edge of the middle step surface of the pressure sensing base 2. The bracket 3 can be a cylindrical body with two ends open. The pressure sensing head 22 can be located in the bracket 3. The side wall of the bracket 3 can be provided with multiple openings 32 to reduce the use of materials. The bracket 3 also includes a fixed foot 31, which can include four fixed feet 31. The fixed foot 31 can be connected to the side wall of the bracket 3 and bend toward the center of the bracket 3.

[0036] like Figure 2 As shown, the pressure sensor includes a first plastic part 5, which is disposed in the inner cavity 11, the bottom of the first plastic part 5 is fixedly connected to the top of the bracket 3, the first plastic part 5 can be a cylindrical plastic part, and the bracket 3 and the first plastic part 5 can be integrally formed by injection molding. The first plastic part 5 is made of nylon 66.

[0037] like Figure 4As shown, the pressure sensor includes a first circuit board 4, which is arranged in the inner cavity 11 and located in the bracket 3. The first circuit board 4 is a rigid PCB circuit board, and the first circuit board 4 can be welded to the fixed foot 31 on the bracket 3. The first circuit board 4 and the pressure-sensing chip 23 on the pressure-sensing base 2 can be electrically connected by aluminum wire welding. The first circuit board 4 has a variety of signal processing components, which can further process the signal transmitted by the pressure-sensing chip 23 to ensure the stability and accuracy of the pressure signal. The first circuit board 4 is located between the first plastic part 5 and the pressure-sensing head 22.

[0038] like Figure 4 As shown, the pressure sensor includes a second circuit board 6, which is a flexible circuit board. The second circuit board 6 can be coated on the periphery of the first plastic part 5. Specifically, the second circuit board 6 can be coated on both sides of the first plastic part 5. The coating can be carried out by bonding, and the bonding material is epoxy resin glue. One end of the second circuit board 6 is electrically connected to the first circuit board 4, and specifically, a seamless pressing connection can be achieved by a pressing machine.

[0039] like Figure 4 As shown, the second circuit board 6 may be provided with contact points 61 at the area above the first plastic part 5 , and the contact points 61 may be four contact points 61 .

[0040] like Figure 2 As shown, the pressure sensor includes an elastic member 7, which may be a coil spring, and the elastic member 7 may include four elastic members 7. Specifically, the elastic member 7 includes a variable pitch section 71 in the middle and a top conical section 72 and a bottom conical section 73 at both ends.

[0041] like Figure 2 As shown, the pressure sensor includes a second plastic part 8, one end of the second plastic part 8 is fixedly connected to the other end of the shell 1, and the fixing can also be achieved by an integrated injection molding process. A limiting hole 81 can be set in the second plastic part 8, and the elastic part 7 is at least partially located in the limiting hole 81. The limiting holes 81 extend from both ends of the elastic part 7. The number of the limiting holes 81 can be set one by one according to the number of elastic parts 7, and the bottom of the elastic part 7 is in extrusion contact with the contact point 61.

[0042] like Figure 2As shown, the top of the limiting hole 81 has a conical structure 81a that matches the top conical section 72 of the elastic member 7. The diameter of each circle of the conical section of the elastic member 7 changes along the axial direction of the elastic member 7. Specifically, the diameter of each circle of the elastic member 7 can be reduced along the outward direction of the limiting hole 81, so that the top conical section 72 can be stuck at the conical structure 81a to form a pre-compression contact with the contact point 61.

[0043] The installation of the utility model may include: integrally injecting the first plastic part 5 and the bracket 3, and gluing the second circuit board 6 to the upper and lower side surfaces of the first plastic part 5, and integrally injecting the second plastic part 8 and the shell 1, and pre-pressing the elastic part 7 into the limiting hole 81 and the contact point 61 on the second circuit board 6, and then fixing the first circuit board 4 and the bracket 3 by welding, and then welding the shell 1 and the pressure-sensing base 2 together. After the pressure sensor is assembled, the elastic part 7 is in a pre-pressed state, ensuring that the elastic part 7 is in stable contact with the contact point 61 on the second circuit board 6, so that the pressure-sensing chip 23 and the signal output by the first circuit board 4 are transmitted to the elastic part 7 through the second circuit board 6, and finally output to the client.

[0044] Therefore, the utility model effectively overcomes various shortcomings in the prior art and has a high industrial utilization value. The above embodiments are only illustrative of the principles and effects of the utility model, and are not used to limit the utility model. Anyone familiar with this technology can modify or change the above embodiments without violating the spirit and scope of the utility model. Therefore, all equivalent modifications or changes made by those with ordinary knowledge in the relevant technical field without departing from the spirit and technical ideas disclosed by the utility model should still be covered by the claims of the utility model.

Claims

1. A pressure sensor, characterized in that: The pressure sensor comprises: a housing having an inner cavity; A pressure-sensitive base, one end of which is fixedly connected to one end of the shell, and the pressure-sensitive base has a pressure-sensitive channel; A bracket is arranged in the inner cavity, one end of the bracket is fixedly connected to the other end of the pressure-sensing base; A first circuit board, wherein the first circuit board is disposed in the inner cavity, one end of the first circuit board is fixedly connected to the other end of the bracket, and the first circuit board is electrically connected to the pressure-sensing base; A first plastic member, disposed in the inner cavity, wherein one end of the first plastic member is fixedly connected to the other end of the bracket; a second plastic member, one end of the second plastic member being fixedly connected to the other end of the housing, and a plurality of limiting holes being arranged in the second plastic member; A plurality of elastic members, respectively matched with the plurality of limiting holes, wherein at least a portion of the elastic members is located in the limiting holes; And a second circuit board is arranged in the inner cavity, the second circuit board is covered on both sides of the first plastic member, and the two sides of the second circuit board are electrically connected to the elastic member and the first circuit board respectively.

2. The pressure sensor according to claim 1, characterized in that: The first circuit board is a rigid circuit board, and the second circuit board is a flexible circuit board.

3. The pressure sensor according to claim 1, characterized in that: The second circuit board has a plurality of contact points which are electrically connected to the plurality of elastic members respectively.

4. The pressure sensor according to claim 1, characterized in that: The second circuit board is bonded to two sides of the first plastic component.

5. The pressure sensor according to claim 1, characterized in that: The pressure-sensitive base includes a pressure-sensitive head with a top and a pressure-sensitive chip arranged on an outer side wall of the pressure-sensitive head. The pressure-sensitive chip is electrically connected to the first circuit board.

6. The pressure sensor according to claim 5, characterized in that: The pressure sensing head is located in the bracket, and the first circuit board is located between the pressure sensing head and the first plastic component and is arranged in the bracket.

7. The pressure sensor according to claim 1, characterized in that: The bracket and the first plastic part are integrally injection-molded, and the shell and the second plastic part are integrally injection-molded.

8. The pressure sensor according to claim 1, characterized in that: The elastic member is a coil spring, and the number of the coil springs is less than or equal to 4.

9. The pressure sensor according to claim 1, characterized in that: The elastic member comprises a variable pitch section in the middle and a top conical section and a bottom conical section at both ends. The diameters of the top conical section and the bottom conical section gradually decrease in the direction outward from the limiting hole.

10. The pressure sensor according to claim 9, characterized in that: The limiting hole has a tapered structure at the top tapered section.

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