MEMS engine oil pressure sensor

Abstract

The utility model relates to an MEMS engine oil pressure sensor, and the sensor comprises a housing assembly which comprises a first opening at one end; the sealing piece is arranged in the shell and divides the internal space of the shell assembly into a first space and a second space which are independent from each other, and the first space is communicated with the first opening; the MEMS chip is configured to convert environment pressure into an electric signal, and the MEMS chip is arranged in the first space; the first circuit board is arranged in the first space and is electrically connected with the MEMS chip; a second circuit board configured to calibrate and amplify the electrical signal; the second circuit board is arranged in the second space and is electrically connected with the first circuit board; and the electric connecting piece is inserted into the shell assembly and is electrically connected with the second circuit board. The MEMS engine oil pressure sensor provided by the embodiment of the utility model has the advantage of small size.

Description

TECHNICAL FIELD

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

[0002] The pressure sensor is a device or apparatus that can sense a pressure signal and convert the pressure signal into an electrical signal according to a certain rule.

[0003] In the current intelligent automobile, the pressure sensor is an essential part of the intelligent automobile, which needs to collect the pressure signal and give it to the host central processor for processing, so that the host can timely process and control various working conditions in the automobile. The pressure sensor is one of the commonly used sensors, which is an important device for detecting the engine oil pressure of the vehicle engine. The detected data can help control the normal operation of the engine. However, the current engine oil pressure sensor is large in size and difficult to meet the use requirements. CONTENT OF THE INVENTION

[0004] Therefore, it is necessary to provide a MEMS engine oil pressure sensor to solve the problem of large size of the sensor.

[0005] The first aspect of the embodiment of the present application provides a MEMS engine oil pressure sensor, which comprises: a shell assembly comprising a first opening at one end; a sealing element arranged in the shell and dividing the internal space of the shell assembly into a first space and a second space which are independent of each other, the first space being in communication with the first opening; a MEMS chip configured to convert an environmental pressure into an electrical signal, the MEMS chip being arranged in the first space; a first circuit board arranged in the first space and electrically connected with the MEMS chip; a second circuit board configured to amplify and calibrate the electrical signal, the second circuit board being arranged in the second space and electrically connected with the first circuit board; and an electrical connector inserted on the shell assembly and electrically connected with the second circuit board.

[0006] In one embodiment, the MEMS chip and the MEMS chip are connected by flip-chip bonding process.

[0007] In one embodiment, the first circuit board comprises a first pad on the board surface facing the first space; and the MEMS chip and the first pad are connected by flip-chip bonding.

[0008] In one embodiment, the MEMS chip comprises a base, a pressure sensing film and a second pad; the pressure sensing film is arranged in the middle of the base, the second pad protrudes from the bottom side of the base facing the circuit board, and the second pad is electrically connected with the first pad.

[0009] In one of the embodiments, the housing assembly comprises an upper cover and a lower shell; the upper cover and the lower shell can be covered with each other to jointly define an internal space of the housing assembly; the first opening is arranged at the bottom of the lower shell, the connecting member is arranged on the upper cover, and the sealing member is arranged in the lower shell.

[0010] In one of the embodiments, the lower shell is formed with a first recess and a second recess at the bottom of the first recess; the first opening is arranged at the bottom of the second recess, and the sealing member closes the opening of the second recess to form the first space; the upper cover covers the first recess.

[0011] In one of the embodiments, the MEMS engine oil pressure sensor comprises a plurality of metal pins; the metal pins penetrate the sealing member; the first circuit board is formed with a first connecting hole matched with one end of the metal pin; the second circuit board is formed with a second connecting hole matched with the other end of the metal pin.

[0012] In one of the embodiments, the sealing member comprises a main body and a shell part, the shell part is wrapped around the outer periphery of the main body, and the metal pin penetrates the main body and extends to the outside of the shell part; the shell part is in a welded sealing connection with the housing assembly.

[0013] In one of the embodiments, the metal pin is made of copper alloy, aluminum alloy or stainless steel.

[0014] In one of the embodiments, the MEMS engine oil pressure sensor comprises a flexible circuit board; the flexible circuit board is arranged in the second space, and the second circuit board is connected with the electric connecting member through the flexible circuit board.

[0015] The beneficial effects are:

[0016] An embodiment of this application discloses a MEMS oil pressure sensor, which sequentially and electrically connects a MEMS chip, a first circuit board, a second circuit board, and electrical connectors. The MEMS chip is mounted on the first circuit board, facing a first opening. The MEMS chip converts the ambient pressure within the first space into an electrical signal. The first circuit board secures the MEMS chip and transmits the electrical signal from the MEMS chip to the second circuit board. The second circuit board then amplifies and adjusts the electrical signal before transmitting it externally through the electrical connectors. Because the MEMS chip itself is very small, the second circuit board amplifies and adjusts the electrical signal, and a housing assembly of suitable thickness accommodates the seal, MEMS chip, first circuit board, second circuit board, and electrical connectors. This results in a MEMS oil pressure sensor that is small in size, has excellent performance, and can adapt to various harsh working conditions. Attached Figure Description

[0017] Figure 1 An exploded view of a MEMS oil pressure sensor provided in some embodiments of this application.

[0018] Figure 2 This is a schematic diagram of the structure of a MEMS oil pressure sensor provided in some embodiments of this application.

[0019] Figure 3 for Figure 2 The image shows an AA cross-sectional view of the MEMS oil pressure sensor.

[0020] Figure 4 for Figure 3 The image shows an enlarged view of region B of the MEMS oil pressure sensor. Detailed Implementation

[0021] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0022] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0023] In the description of the embodiments of the present application, if these technical terms "first", "second" and the like appear, these terms are only used for the purpose of description, to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features.

[0024] Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment can be included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive or alternative embodiments. It is explicitly and implicitly understood that the embodiments described herein can be combined with other embodiments.

[0025] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " in this paper generally represents that the front and rear associated objects are a "or" relationship.

[0026] In the description of the embodiments of the present application, if the term "multiple" appears, the meaning of "multiple" is at least two (including two), for example, two, three, etc., unless otherwise explicitly and specifically limited. Similarly, if the term "multiple groups" appears, "multiple groups" refers to two groups or more (including two groups), and if the term "multiple pieces" appears, "multiple pieces" refers to two pieces or more (including two pieces).

[0027] In the description of the embodiments of the present application, if these terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like appear, the orientation or positional relationship indicated by these terms is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the embodiments of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the embodiments of the present application.

[0028] In the description of the embodiments of the present application, unless specifically defined and limited otherwise, if there are technical terms such as "installation", "connection", "connection", "fixation" and the like, these terms should be interpreted in a broad sense. For example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; 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; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0029] In the present application, unless specifically defined and limited otherwise, if there are similar descriptions such as "on" or "below" the first feature of the second feature, it means that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature "above", "above" and "above" the second feature can be directly above or obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature can be directly below or obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0030] It should be noted that if an element is referred to as "fixed to" or "disposed to" another element, it can be directly on another element or there can be a middle element. If an element is considered to be "connected" to another element, it can be directly connected to another element or there can be a middle element. If present, the terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used in the present application are only for the purpose of illustration, and do not represent the only implementation.

[0031] The first aspect of the embodiments of the present application provides a MEMS engine oil pressure sensor.

[0032] Referring to Figures 1 to 4 , the MEMS engine oil pressure sensor comprises a housing assembly 10, a sealing member 40, a MEMS chip 30, a first circuit board 20, a second circuit board 50 and an electrical connector 60.

[0033] The shell assembly 10 comprises a first opening 11 at one end; a sealing member 40 is arranged in the shell 10, the sealing member 40 divides the internal space of the shell assembly 10 into a first space 13 and a second space 14 which are independent of each other, the first space 13 communicates with the first opening 11; a MEMS chip 30 is configured to convert the ambient pressure into an electrical signal, the MEMS chip 30 is arranged in the first space 13; a first circuit board 20 is arranged in the first space 13 and electrically connected with the MEMS chip 30; a second circuit board 50 is configured to amplify and calibrate the electrical signal; the second circuit board 50 is arranged in the second space 14 and electrically connected with the first circuit board 20; and an electrical connector 60 is inserted on the shell assembly 10 and electrically connected with the second circuit board 50.

[0034] In the related art, the working environment of a vehicle is very harsh, and the performance requirement and volume requirement of a sensor are very strict. For example, in the design requirement of a pressure sensor used for vehicle oil, not only high temperature resistance, corrosion resistance and high precision are required, but also performance reliability, wide working temperature range and anti-interference measures are required to improve the reliability of the sensor. In addition, the installation space in the vehicle is small, and the pressure sensor needs to be small in volume and occupy less space. However, the existing pressure sensor used for vehicle oil is generally a thick film pressure sensor chip or a ceramic piezoresistive sensor core. Although these two chips can meet the harsh working environment, the volume of the thick film pressure sensor chip or the ceramic piezoresistive sensor core itself (generally 18mm in outer diameter and 3.5mm or more in thickness) is already very large, and the overall volume is too large due to the corresponding circuit and shell structure, which is difficult to meet the use requirement.

[0035] The MEMS chip 30 is a pressure chip using a micro-electromechanical system (Micro-electromechanical Systems, hereinafter referred to as MEMS). Compared with the thick film pressure sensor chip or the ceramic piezoresistive sensor core in the related art, the MEMS chip 30 has the characteristics of small volume, light weight, low cost, low power consumption, high reliability, suitable for batch production, easy to integrate and realize intelligentization, etc. The inside of the MEMS chip 30 is generally at the micron or even nanometer level, so it can complete some functions that traditional mechanical sensors cannot realize.

[0036] In the embodiments of the present application, the MEMS chip 30, the first circuit board 20, the second circuit board 50 and the electrical connector 60 are sequentially electrically connected. The MEMS chip 30 is arranged on the first circuit board 20, and faces the first opening 11. The MEMS chip 30 is used to convert the ambient pressure in the first space 13 into an electrical signal. The first circuit board 20 is used to fix the MEMS chip 30, and transmit the electrical signal of the MEMS chip 30 to the second circuit board 50 through the first circuit board 20. The electrical signal is adjusted and amplified by the second circuit board 50, and then transmitted to the outside through the electrical connector 60.

[0037] In this way, the MEMS engine oil pressure sensor can timely feedback the change of the ambient pressure. Since the volume of the MEMS chip 30 is very small (for example, can be reduced to 1.6mm*1.6mm*0.9mm), the performance of the MEMS chip 30 is more excellent than that of the thick film pressure sensor or the ceramic piezoresistive sensor. The electrical signal is adjusted and amplified by the second circuit board 50. The shell assembly 10 with a proper thickness is used to accommodate the sealing member 40, the MEMS chip 30, the first circuit board 20, the second circuit board 50 and the electrical connector 60. Therefore, the MEMS engine oil pressure sensor has the advantages of small volume, excellent performance and adaptability to various harsh working conditions.

[0038] In some possible embodiments, referring to Figures 1 to 4 The first circuit board 20 is fixed on the bottom surface of the sealing member 40 facing the first space 13. The first circuit board 20 is used to weld and fix the MEMS chip 30, and then transmit the electrical signal of the MEMS chip 30. The first circuit board 20 can use ceramic material as the base material of the circuit board, which has the advantages of high and low temperature resistance, high pressure resistance, corrosion resistance, hard deformation and small deformation, etc. Therefore, the first circuit board 20 will not generate stress to affect the precision of the MEMS chip 30.

[0039] The second circuit board 50 is fixed on the top surface of the sealing member 40 facing the second space 14. The second circuit board 50 can be used to calibrate and amplify the electrical signal. The second circuit board 50 can withstand various harsh working conditions that the vehicle may face during operation, and has excellent circuit processing and amplification capacity and EMC anti-interference function, so as to ensure the smooth transmission of the signal.

[0040] Those skilled in the art should know that the first circuit board 20 and the second circuit board 50 can be installed with electronic components and other structures necessary for pressure detection. For example, a conditioning and amplification circuit and components can be installed on the second circuit board 50, so as to condition and amplify the weak electrical signal transmitted by the MEMS chip 30, and then transmit the processed electrical signal to the electrical connector 60. The present application will not be described here.

[0041] In some possible embodiments, referring toFigures 1 to 4 As shown, a part of the connecting piece 60 extends into the second space 14, and another part of the connecting piece 60 is located outside the housing assembly 10 for connecting the external environment. In this way, the electrical signals of the MEMS chip 30 are transmitted to the second circuit board 50 through the first circuit board 20; and then the electrical signals are amplified by the second circuit board 50 and transmitted to the external environment through the electrical connecting piece 60, so that the MEMS engine oil pressure sensor as a whole has small volume, excellent performance, and can adapt to various harsh working conditions.

[0042] In some possible embodiments, referring to Figure 1 As to Figure 4 As shown, the MEMS chip 30 is connected with the MEMS chip 30 by flip-chip technology. In this way, the MEMS chip 30 can face the first opening 11, so as to better perceive the environmental pressure, and the detection accuracy of the MEMS engine oil pressure sensor is high.

[0043] In some possible embodiments, referring to Figure 1 As to Figure 4 As shown, the first circuit board 20 includes a first pad 21 on the board surface facing the first space 13; and the MEMS chip 30 is connected with the first pad 21 by flip-chip technology.

[0044] Specifically, the MEMS chip 30 includes a base 31, a pressure sensing diaphragm 32, and a second pad 33.

[0045] The base 31 is a basic carrier of the MEMS chip 30, and those skilled in the art should know that electronic elements and other structures necessary for the MEMS chip 30 can be arranged thereon.

[0046] The pressure sensing diaphragm 32 is arranged at the middle part of the base 31. The pressure sensing diaphragm 32 is a mechanical structure part in the MEMS chip 30, and can be used to perceive the pressure signal in the external environment. The pressure sensing diaphragm 32 generates corresponding diaphragm deformation by perceiving the pressure signal caused by the pressure change, and then the mechanical variable is measured and converted into a corresponding electrical signal. The pressure sensing diaphragm 32 can be set to different thicknesses according to different detection pressure ranges, and the embodiments of the present application are not limited thereto.

[0047] The second pad 33 protrudes from the bottom side of the base 31 facing the circuit board 20. The distance between the second pad 33 protruding from the lower surface of the base 31 is usually kept at about 0.05mm-0.5mm, and the second pad 33 can be a copper pad or an aluminum pad, and the embodiments of the present application are not limited thereto.

[0048] The second pad 33 is electrically connected with the first pad 21. In this way, the two are welded and fixed by means of flip-chip technology, which can avoid the connection between the first circuit board 20 and the MEMS chip 30 by means of adhesive welding and the like, and make the interconnection line between the first circuit board 20 and the MEMS chip 30 shorter, thereby reducing the parasitic capacitance and parasitic inductance between the two, and ensuring the normal and stable implementation of the function of the MEMS engine oil pressure sensor.

[0049] In some possible embodiments, referring to Figure 1 As shown in Figure 4 The MEMS engine oil pressure sensor includes a solder ball 70, which is connected between the first pad 21 and the second pad 33.

[0050] Specifically, the MEMS engine oil pressure sensor includes four solder balls 70, and correspondingly, the first circuit board 20 can include four first pads 21, which can be arranged on the board surface of the board body facing the first space 13. The MEMS chip 30 includes four second pads 33, which face the top side of the circuit board 20. One solder ball 70 is arranged between each first pad 21 and the corresponding second pad 33. The solder ball 70 can be a tin ball, which has good electrical conductivity. The reflow soldering is adopted to melt the solder ball 70 and form a conductive layer between the first pad 21 and the second pad 33. The pressure-sensitive diaphragm 32 generates corresponding diaphragm deformation by sensing the pressure signal caused by the pressure change, and then mechanically measures and converts the mechanical variable into a corresponding electrical signal. The electrical signal is transmitted to the second pad 33 and then transmitted to the first pad 21 through the solder ball 70 to realize the transmission of the electrical signal.

[0051] In the embodiments of the present application, the solder ball 70 is used for welding, which is relative to the traditional bonding method of wire bonding. Because the bonding wire can be cancelled, the on-resistance of the device drain and source electrode to the PCB board is greatly reduced, and the parasitic effect caused by the bonding wire is greatly reduced.

[0052] Optionally, the MEMS chip 30 can be a 1.6*1.6mm pressure detection chip. The base 31 projects as a square component with a side length of 1.6mm in the vertical direction. The four second pads 33 are arranged on the four corners of the bottom surface of the base 31, and the distance between the adjacent two second pads 33 is 1mm. In this way, a sufficient distance is maintained to avoid short circuit between the solder balls 70.

[0053] Optionally, in order to strengthen the connection between the second pad 33 and the first pad 21 through the solder ball 70, the first pad 21 is a copper pad, and the second pad 33 is an aluminum pad. After the solder ball 70 made of tin is melted, a good welding effect can be achieved with the aluminum pad and the copper pad, which not only has good electrical conductivity, but also has high connection strength.

[0054] In some possible embodiments, referring to Figures 1 to 4 As shown in the drawings, the shell assembly 10 comprises an upper cover 15 and a lower shell 16; the upper cover 15 and the lower shell 16 can be covered with each other to jointly define an internal space of the shell assembly 10; a first opening 11 is arranged at the bottom of the lower shell 16; a connecting piece 60 is inserted on the upper cover 15; and a sealing piece 40 is arranged in the lower shell 16.

[0055] The upper cover 15 and the lower shell 16 can be hollow structures with one side open, and the opening side of the first part 111 is covered on the opening side of the second part 112; the upper cover 15 and the lower shell 16 are connected by welding sealing. Specifically, the lower shell 16 is formed with a first groove 161 and a second groove 162 at the bottom of the first groove 161; the first opening 11 is arranged at the groove bottom of the second groove 162, and the sealing piece 40 closes the groove of the second groove 162 to form a first space 13; and the upper cover 15 covers the first groove 161.

[0056] The lower shell 16 can be made of copper alloy, aluminum alloy or stainless steel, and the embodiments of the present application do not limit this. The first opening 11 is drilled at the bottom of the lower shell 16 for allowing external liquid or gas to enter the first space 13 through the first opening 11. The lower shell 16 and the shell part (mentioned below) of the sealing piece 40 are welded together by laser welding to form a pressure-bearing first space 13. Since the wall surfaces around the first space 13 are all made of stainless steel and have a certain thickness, the first space 13 can withstand a maximum pressure of 30 Mpa without bursting and deforming. The size of the lower shell 16 cooperates with the upper cover 15 to adapt to the installation size in the vehicle and improve the space utilization.

[0057] The upper cover 15 can be made of copper alloy, aluminum alloy or stainless steel; the embodiments of the present application do not limit this. The connecting piece 60 is inserted on the upper cover 15, and the connecting piece 60 can be three metal columns which are specifically embedded in the upper cover 15 by glass, so as to realize sealing and electrical connection.

[0058] The metal columns can be made of copper alloy, aluminum alloy or stainless steel, and the surface can be plated with gold to improve its corrosion resistance and high and low temperature resistance. The connecting piece 60 and the second circuit board 50 realize electrical connection, can supply power to the whole MEMS engine oil pressure sensor, and the MEMS engine oil pressure sensor can transmit the feedback pressure electrical signal to the outside through the connecting piece 60.

[0059] In some possible embodiments, referring to Figures 1 to 4 As shown in the drawings, the MEMS engine oil pressure sensor comprises a plurality of metal pins 41; the metal pins 41 penetrate the sealing piece 40; the first circuit board 20 is formed with a first connecting hole 21 matched with one end of the metal pin 41; and the second circuit board 50 is formed with a second connecting hole 51 matched with the other end of the metal pin 41.

[0060] The metal needle 41 can be made of copper alloy, aluminum alloy or stainless steel, and the surface can be plated with gold to improve its corrosion resistance and temperature resistance.

[0061] The first circuit board 20 is formed with a first connecting hole 21 matched with one end of the metal needle 41, and the second circuit board 50 is formed with a second connecting hole 51 matched with the other end of the metal needle 41, and the two are connected by glass or insulating glue. In this way, the first circuit board 20 and the second circuit board 50 are electrically connected through the metal needle 41, the MEMS chip 30 converts the environmental pressure in the first space 13 into an electrical signal, and the first circuit board 20 transmits the electrical signal of the MEMS chip 30 to the second circuit board 50 through the metal needle 41, thereby ensuring the stable realization of the function of the MEMS oil pressure sensor.

[0062] In some possible embodiments, the sealing member 40 includes a main body portion (not labeled) and a shell portion (not labeled), the shell portion is wrapped around the outer periphery of the main body portion, and the metal needle 41 penetrates through the main body portion and extends to the outside of the shell portion; the shell portion is welded and sealed to the shell assembly 10.

[0063] Specifically, the lower shell 16 and the shell portion of the sealing member 40 are welded together by laser welding to form the pressure-bearing first space 13, which can withstand a pressure of 30 MPa without bursting or deforming. The metal needle 41 penetrates through the main body portion and extends to the outside of the shell portion; the MEMS chip 30 converts the environmental pressure in the first space 13 into an electrical signal, and the first circuit board 20 transmits the electrical signal of the MEMS chip 30 to the second circuit board 50 through the metal needle 41, thereby ensuring the stable realization of the function of the MEMS oil pressure sensor.

[0064] Optionally, the main body portion can be made of glass, rubber, ceramic or plastic, and the shell portion can be made of copper alloy, aluminum alloy or stainless steel, and the embodiments of the present application do not limit this.

[0065] In some possible embodiments, referring to Figures 1 to 4 As shown in the figure, the MEMS oil pressure sensor includes a flexible circuit board 80; the flexible circuit board 80 is arranged in the second space 14, and the second circuit board 50 and the electrical connector 60 are connected through the flexible circuit board 80.

[0066] The flexible circuit board 80 is made of flexible material, and generally includes an insulating substrate and a conductive foil printed on the insulating substrate. The insulating substrate can be made of high molecular material such as polyimide (PI) or polyester film (PET), and the conductive foil can be copper foil. The flexible circuit board 80 has good heat dissipation and weldability, and is easy to assemble and has low comprehensive cost; and can flexibly connect the circuit in the narrow second space 14.

[0067] The flexible circuit board 80 can transmit the electrical signal transmitted by the second circuit board 50 to the electrical connector 60, and then transmit the pressure signal to the outside; meanwhile, the outside can supply power to the second circuit board 50, the first circuit board 20 and the MEMS chip 30 through the electrical connector 60 and the flexible circuit board 80.

[0068] The second aspect of the present application provides a vehicle, which comprises the MEMS engine oil pressure sensor described above. The MEMS engine oil pressure sensor can be used to sense the engine oil or other gas-liquid pressure in the vehicle.

[0069] Specifically, the engine oil or other gas-liquid enters the first space 13 sealed by the pressure through the first opening 11 at the bottom of the housing assembly 10, and the pressure sensing diaphragm 32 of the MEMS chip 30 in the first space 13 deforms slightly to generate a corresponding electrical signal; the electrical signal is transmitted to the second circuit board 50 through the first circuit board 20, and the second circuit board 50 calibrates and amplifies the original electrical signal to output a standard analog signal or digital signal, and then the signal is connected to the control system (not shown) of the vehicle through the electrical connector 60, so that the pressure signal can be fed back in real time, and the control system can control the operation of each part.

[0070] The technical features of the above-described embodiments can be combined in any manner. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described, but as long as the combinations of the technical features do not contradict, they should be considered as within the scope of the present application.

[0071] The above-described embodiments only express several embodiments of the present application, and the description is relatively specific and detailed, but it should not be understood as a limitation on the scope of the patent application. It should be pointed out that for ordinary skilled persons in the art, some modifications and improvements can be made without departing from the concept of the present application, and these are within the scope of protection of the present application. Therefore, the scope of protection of the patent of the present application should be subject to the appended claims.

Claims

1. A MEMS oil pressure sensor, characterized in that, The MEMS oil pressure sensor includes: The housing assembly (10) includes a first opening (11) at one end. A sealing element (40) is disposed inside the housing (10) and divides the internal space of the housing assembly (10) into a first space (13) and a second space (14) that are independent of each other. The first space (13) is connected to the first opening (11). MEMS chip (30) is configured to convert environmental pressure into an electrical signal, and the MEMS chip (30) is disposed in the first space (13); The first circuit board (20) is disposed in the first space (13) and electrically connected to the MEMS chip (30); The second circuit board (50) is configured to amplify and adjust electrical signals; the second circuit board (50) is disposed in the second space (14) and electrically connected to the first circuit board (20); And an electrical connector (60) is inserted into the housing assembly (10) and electrically connected to the second circuit board (50).

2. The MEMS oil pressure sensor according to claim 1, characterized in that, The MEMS chips (30) are connected to each other using a flip-chip bonding process.

3. The MEMS oil pressure sensor according to claim 1, characterized in that, The first circuit board (20) includes a first pad (21) on the board surface facing the first space (13); the MEMS chip (30) is flip-chip bonded to the first pad (21).

4. The MEMS oil pressure sensor according to claim 3, characterized in that, The MEMS chip (30) includes a base (31), a pressure-sensitive membrane (32), and a second pad (33); the pressure-sensitive membrane (32) is disposed in the middle of the base (31), and the second pad (33) protrudes from the bottom side of the base (31) facing the circuit board (20), and the second pad (33) is electrically connected to the first pad (21).

5. The MEMS oil pressure sensor according to any one of claims 1 to 4, characterized in that, The housing assembly (10) includes an upper cover (15) and a lower cover (16). The upper cover (15) and the lower shell (16) can close together to define the internal space of the shell assembly (10); The first opening (11) is located at the bottom of the lower shell (16), the connector (60) is inserted into the upper cover (15), and the sealing member (40) is located inside the lower shell (16).

6. The MEMS oil pressure sensor according to claim 5, characterized in that, The lower shell (16) has a first groove (161) and a second groove (162) located at the bottom of the first groove (161). The first opening (11) is located at the bottom of the second groove (162), and the sealing member (40) closes the opening of the second groove (162) to form the first space (13). The upper cover (15) fits over the first groove (161).

7. The MEMS oil pressure sensor according to any one of claims 1 to 4, characterized in that, The MEMS oil pressure sensor includes multiple metal needles (41); the metal needles (41) penetrate the seal (40); The first circuit board (20) has a first connection hole (21) that is adapted to one end of the metal pin (41). The second circuit board (50) has a second connection hole (51) that is adapted to the other end of the metal pin (41).

8. The MEMS oil pressure sensor according to claim 7, characterized in that, The sealing element (40) includes a main body and a shell, the shell covering the outer periphery of the main body, and the metal needle (41) penetrating the main body and extending to the outside of the shell; The shell portion is welded and sealed to the shell assembly (10).

9. The MEMS oil pressure sensor according to claim 7, wherein the metal needle (41) is made of copper alloy, aluminum alloy or stainless steel.

10. The MEMS oil pressure sensor according to any one of claims 1 to 4, characterized in that, The MEMS oil pressure sensor includes a flexible circuit board (80); the flexible circuit board (80) is disposed in the second space (14), and the second circuit board (50) is connected to the electrical connector (60) through the flexible circuit board (80).

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