Pressure sensor

Abstract

The present disclosure relates to a pressure sensor comprising: a housing in which a first pressure port and a second pressure port isolated from each other are provided; the electronic assembly component is installed in the shell and comprises a first absolute pressure sensing element, a second absolute pressure sensing element and a processing unit, and the processing unit comprises a first output end and a second output end. The first output is configured to provide a pressure difference measurement value representing a pressure difference between a first fluid pressure and a second fluid pressure based on a first absolute pressure detection signal generated by the first absolute pressure sensing element and a second absolute pressure detection signal generated by the second absolute pressure sensing element. The second output is configured to provide an absolute pressure measurement representative of the first fluid pressure or the second fluid pressure based on the first absolute pressure detection signal or the second absolute pressure detection signal.

Description

Technical Field

[0001] This disclosure relates to a pressure sensor. Background Technology

[0002] Pressure sensors are commonly used in industrial practice and are widely applied in various industrial environments. For example, pressure sensors can be used in diesel particulate filters (DPF), gasoline particulate filters (GPF), and exhaust gas recirculation (EGR) systems in vehicles to detect the pressure of exhaust gases.

[0003] Figure 6 This is an illustration of a conventional dual-mode absolute pressure sensor. (As shown...) Figure 6 As shown, the dual-mode absolute pressure sensor includes a first absolute pressure sensing element and a second absolute pressure sensing element. The first absolute pressure sensing element is configured to detect a first fluid pressure P1 in the pipeline at a first measurement point and generate a first absolute pressure detection signal. The second absolute pressure sensing element is configured to detect a second fluid pressure P2 in the pipeline at a second measurement point and generate a second absolute pressure detection signal. The processing unit receives the first and second absolute pressure detection signals and performs necessary signal processing and calculations, thereby outputting the absolute pressure measurement value P1out of the first fluid pressure P1 based on the first absolute pressure detection signal and the absolute pressure measurement value P2out of the second fluid pressure P2 based on the second absolute pressure detection signal.

[0004] However, in typical applications such as DPF, GPF, and EGR, it is usually only necessary to use the pressure difference between the fluid pressure P1 at the first upstream measurement point and the fluid pressure P2 at the second downstream measurement point. This pressure difference is used, for example, for controlling and diagnosing faults in DPF regeneration, GPF regeneration, and exhaust gas recirculation (EGR) systems. In such cases, Figure 6 The dual-mode absolute pressure sensor shown cannot directly provide a differential pressure signal. Instead, the electronic control unit (ECU) needs to calculate the differential pressure value by measuring the fluid pressure P1 (P1out) and the fluid pressure P2 (P2out). The accumulated error results in a low accuracy of the obtained differential pressure value. Utility Model Content

[0005] To address the problems existing in the prior art, this disclosure provides a pressure sensor that can not only provide high-precision differential pressure measurements, but also provide absolute pressure measurements as needed.

[0006] According to one aspect of this disclosure, a pressure sensor is provided, the pressure sensor comprising: a housing having a first pressure port and a second pressure port isolated from each other within the housing; and an electronic assembly mounted in the housing, the electronic assembly including a first absolute pressure sensing element, a second absolute pressure sensing element, and a processing unit, the first absolute pressure sensing element being configured to detect a first fluid pressure in the first pressure port and generate a first absolute pressure detection signal, the second absolute pressure sensing element being configured to detect a second fluid pressure in the second pressure port and generate a second absolute pressure detection signal, the processing unit including a first output terminal and a second output terminal, the first output terminal being configured to provide a differential pressure measurement value representing the pressure difference between the first fluid pressure and the second fluid pressure based on the first absolute pressure detection signal and the second absolute pressure detection signal, and the second output terminal being configured to provide an absolute pressure measurement value representing the first fluid pressure or the second fluid pressure based on the first absolute pressure detection signal or the second absolute pressure detection signal.

[0007] In one embodiment of the pressure sensor, the second output terminal can be enabled or disabled.

[0008] In one embodiment of the pressure sensor, the processing unit includes a carrier, an encapsulation module, and a circuit module, wherein the encapsulation module and the circuit module are fixed to the carrier.

[0009] In one embodiment of the pressure sensor, the packaging module may be a grid array packaging module, a BGA packaging module, a QFN packaging module, or a QFP packaging module.

[0010] In one embodiment of the pressure sensor, the circuit module includes a circuit board, the packaging module includes a processing chip, the packaging module is electrically connected to the circuit board via a first electrical connection structure, and the circuit board is electrically connected to an external terminal on the housing via a second electrical connection structure. The first absolute pressure sensing element, the second absolute pressure sensing element, and the processing chip can be integrated in the packaging module.

[0011] In one embodiment of the pressure sensor, the circuit board may be a printed circuit board or a flexible circuit board.

[0012] In one embodiment of the pressure sensor, the first electrical connection structure may be a bonding wire, surface mount technology (SMT), solder wire, or solder strip.

[0013] In one embodiment of the pressure sensor, the second electrical connection structure may be a crimped or welded structure.

[0014] In one embodiment of the pressure sensor, the processing unit includes a carrier, a printed circuit board, and a ceramic plate disposed between the carrier and the printed circuit board. The printed circuit board includes a processing chip, and the printed circuit board and the ceramic plate are fixed to the carrier.

[0015] In one embodiment of the pressure sensor, the operating temperature range of the pressure sensor is -40°C to 150°C.

[0016] In one embodiment of the pressure sensor, the differential pressure measurement value provided by the first output terminal of the pressure sensor can achieve range calibration in the range of -200 kPa to 200 kPa, and the absolute pressure measurement value provided by the second output terminal of the pressure sensor can achieve range calibration in the range of 0 to 220 kPa.

[0017] In one embodiment of the pressure sensor, the pressure sensor includes an output terminal, wherein the first output terminal and the second output terminal are integrated in the output terminal.

[0018] In one embodiment of the pressure sensor, the pressure sensor includes a first output terminal and a second output terminal, wherein the first output terminal is used as the first output terminal and the second output terminal is used as the second output terminal.

[0019] In one embodiment of the pressure sensor, the output form of the differential pressure measurement and the absolute pressure measurement can be an analog signal or a digital signal. Attached Figure Description

[0020] The various objectives, features, and advantages of this disclosure will become more apparent from the following description of preferred embodiments of the disclosure, taken in conjunction with the accompanying drawings. The drawings are merely illustrative of the present disclosure and are not necessarily drawn to scale. In the drawings, the same reference numerals always denote the same or similar parts.

[0021] Figure 1 This is a cross-sectional schematic diagram of a pressure sensor according to this disclosure.

[0022] Figure 2 This is a perspective view of one embodiment of the electronic assembly in the pressure sensor according to the present disclosure.

[0023] Figure 3 yes Figure 2 The diagram shows a cross-sectional view of the electronic assembly.

[0024] Figure 4 This is a perspective view of another embodiment of the electronic assembly in the pressure sensor according to the present disclosure.

[0025] Figure 5 yes Figure 4 The diagram shows a cross-sectional view of the electronic assembly.

[0026] Figure 6 This is a functional diagram illustrating a conventional dual-mode absolute pressure sensor.

[0027] Figure 7 This is a functional diagram of the pressure sensor based on this disclosure.

[0028] Figure 8A This is a functional illustration diagram of one embodiment of the external terminals of the pressure sensor according to the present disclosure. Figure 8B This is a functional illustration diagram of another embodiment of the external terminals of the pressure sensor according to the present disclosure.

[0029] List of reference numerals in the attached diagram:

[0030] 1-Housing; 2-Electronic assembly; 3-Cover plate; 4-Upper sealant; 5-Lower sealant; 6-Metal terminal; 7-External terminal; 8-Inner cavity; 9, 9A-First pressure port; 10, 10A-Second pressure port; 21-Encapsulation module; 22, 22A-Circuit board; 23, 23A-Carrier; 24-Bonding wire; 25, 25A-Opening; 26, 26A-Adhesive; 27, 27A-First absolute pressure sensing element; 28, 28A-Second absolute pressure sensing element; 29, 29A-Processing chip; 30-Ceramic plate; 31-Sealant; P1-First fluid pressure; P2-Second fluid pressure; P1out-Absolute pressure measurement of the first fluid pressure; P2out-Absolute pressure measurement of the second fluid pressure; ΔPout-Differential pressure measurement. Detailed Implementation

[0031] The present disclosure will now be described with reference to the accompanying drawings, which illustrate embodiments of the present disclosure. However, it should be understood that the present disclosure can be presented in many different ways and is not limited to the embodiments described below; in fact, the embodiments described below are intended to make the disclosure more complete and to fully illustrate the scope of protection of the present disclosure to those skilled in the art. It should also be understood that the embodiments disclosed herein can be combined in various ways to provide further additional embodiments.

[0032] It should be understood that the same reference numerals denote the same elements in all the accompanying drawings. For clarity, the dimensions of certain features may be modified in the drawings.

[0033] Unless otherwise stated, the terminology used herein (including technical and scientific terms) should have the meaning that would be normally understood by one of ordinary skill in the art to which this disclosure pertains. Unless otherwise stated, the terms “comprising,” “including,” “having,” and similar terms as used in the specification and claims should be interpreted in an open-ended sense, that is, “comprising,” “including,” and “having” should be interpreted as synonymous with the terms “at least comprising,” “at least containing,” and “at least having.”

[0034] Unless otherwise stated, the directional terms “upper,” “lower,” “top,” “bottom,” etc., used in this disclosure refer to the relative orientation of the pressure sensor assembly in the state shown in the accompanying drawings.

[0035] The ordinal words “first”, “second”, etc., used in this disclosure are merely for distinguishing terms and do not impose any restrictions on the order, importance, or compositional differences of the features being modified.

[0036] It should be understood that the terminology used in this specification is for describing specific embodiments only and is not intended to limit this disclosure. For the sake of brevity and / or clarity, well-known functions or structures may not be described in detail.

[0037] The pressure sensor described in this disclosure can be used to measure both absolute and relative pressure. It can be used to measure gas pressure in vehicles such as diesel particulate filters (DPF), gasoline particulate filters (GPF), or exhaust gas recirculation (EGR) systems. The pressure sensor can also be applied to other applications requiring pressure measurement.

[0038] like Figure 1 As shown, the pressure sensor according to this disclosure includes a housing 1 and an electronic assembly 2. The housing 1 can be made of plastic or any suitable material. The electronic assembly 2 is mounted in the housing 1. Specifically, the electronic assembly 2 can be disposed in the inner cavity 8 of the housing 1 and fixed to the housing 1 by a lower sealant 5, thereby defining a first pressure port 9 and a second pressure port 10 isolated from each other within the housing 1. In addition, a cover plate 3 can be fixed to the upper part of the housing 1 by an upper sealant 4, thereby sealing the electronic assembly 2 in the inner cavity 8 of the housing 1.

[0039] Figure 2 and Figure 3 One embodiment of the electronic assembly 2 is shown. For example... Figure 2 and Figure 3As shown, the electronic assembly 2 includes a first absolute pressure sensing element 27, a second absolute pressure sensing element 28, and a processing unit. The first absolute pressure sensing element 27 is configured to detect a first fluid pressure P1 in the first pressure port 9 and generate a first absolute pressure detection signal. The second absolute pressure sensing element 28 is configured to detect a second fluid pressure P2 in the second pressure port 10 and generate a second absolute pressure detection signal. Thus, the two independent absolute pressure sensing elements can detect the fluid pressure at two different detection points in the pipeline and generate corresponding absolute pressure detection signals. Preferably, the absolute pressure detection signal can be a voltage signal generated by a Wheatstone bridge composed of piezors in the absolute pressure sensing elements.

[0040] like Figure 2 and Figure 3 As shown, the processing unit may include a packaging module 21, a circuit module, and a carrier 23. The packaging module 21 may be an LGA (Large Grid Array) package module, a BGA (Browser Grid Array) package module, a QFN (Quick Flyer Array) package module, or a QFP (Quick Fastener Array) package module. The number of packaging modules 21 may be one or more. Using packaging modules can simplify the structure of the pressure sensor and reduce costs.

[0041] The carrier 23 can be made of plastic or any other suitable material. The carrier 23 can be fixed inside the housing 1 by the lower sealant 5.

[0042] The circuit module may include circuit board 22, and the packaging module 21 may include processing chip 29. Circuit board 22 may be a printed circuit board (PCB), a flexible circuit board (FCB), or any other suitable circuit board. The printed circuit board may be a BT board. Packaging module 21 and circuit board 22 may be fixed to carrier 23, thereby achieving separation and sealing of the first pressure port 9 and the second pressure port 10 on carrier 23. Such fixing may be achieved by adhesive 26 or other suitable fixing methods. The first absolute pressure sensing element 27, the second absolute pressure sensing element 28, and the processing chip 29 may be integrated into packaging module 21.

[0043] The packaging module 21 is connected to the circuit board 22 via a first electrical connection structure. This first electrical connection structure can be a bonding wire 24, surface mount technology (SMT), solder wire, solder ribbon, or any other suitable electrical connection method. The circuit board 22 is connected to the external terminal 7 on the housing 1 via a second electrical connection structure. This second electrical connection structure can be a crimp structure (e.g., fisheye PIN crimp), a solder structure (e.g., solder joint), or any other suitable electrical connection method. For example, at least one opening 25 can be provided on the circuit board 22, through which the electronic assembly 2 can be connected to the metal terminal 6 on the housing. Additionally, at least one external terminal 7 is correspondingly provided on the housing 1. The metal terminal 6 and the external terminal 7 can be integrally molded and injection molded into the housing 1 as inserts.

[0044] Figure 4 and Figure 5 Another embodiment of the electronic assembly 2 is shown. For example... Figure 4 and Figure 5 As shown, the electronic assembly 2 includes a first absolute pressure sensing element 27A, a second absolute pressure sensing element 28A, and a processing unit. The processing unit may include a printed circuit board 22A, a carrier 23A, and a ceramic plate 30 disposed between the printed circuit board 22A and the carrier 23A. The printed circuit board 22A includes a processing chip 29A. For example, the processing chip 29A and other electronic components can be mounted on the printed circuit board 22A via surface mounting. The printed circuit board 22A and the ceramic plate 30 are fixed to the carrier 23A. Specifically, the printed circuit board 22A and the ceramic plate 30 can be bonded together with adhesive 26A, the first absolute pressure sensing element 27A and the second absolute pressure sensing element 28A are fixed to the ceramic plate 30, and the entire assembly is fixed to the carrier 23A with sealant 31, thereby achieving separation and sealing of the first pressure port 9A and the second pressure port 10A on the carrier 23A. Additionally, at least one opening 25A can be provided on the printed circuit board 22A, through which the electronic assembly 2 can be connected to the metal terminal 6 on the housing. At least one external terminal 7 is correspondingly provided on the housing 1. The metal terminal 6 and the external terminal 7 may be integrally molded and injection molded into the housing 1 as inserts.

[0045] Figure 4 and Figure 5 The other structures and configurations of the electronic assembly 2 shown are similar to those of the electronic assembly component 2. Figure 2 and Figure 3 The electronic assembly component 2 shown is largely the same, so its description will be omitted.

[0046] The following will combine Figure 7 Explain the working process of the pressure sensor according to this disclosure. For example... Figure 7As shown, a first absolute pressure sensing element is configured to detect a first fluid pressure P1 in the first pressure port 9 and generate a first absolute pressure detection signal. A second absolute pressure sensing element is configured to detect a second fluid pressure P2 in the second pressure port 10 and generate a second absolute pressure detection signal. The processing unit receives the first and second absolute pressure detection signals, performs signal processing on them by the circuit module, and outputs differential pressure measurements and / or absolute pressure measurements from the pressure sensors. The output of the differential pressure measurements and absolute pressure measurements can be in the form of analog signals (e.g., voltage signals). Alternatively, the output of the differential pressure measurements and absolute pressure measurements can also be in the form of digital signals.

[0047] The processing unit includes a first output terminal and a second output terminal. The first output terminal provides a differential pressure measurement value ΔPout, representing the pressure difference between a first fluid pressure P1 and a second fluid pressure P2, based on a first absolute pressure detection signal and a second absolute pressure detection signal. The second output terminal provides an absolute pressure measurement value P1out representing the first fluid pressure P1 or an absolute pressure measurement value P2out representing the second fluid pressure P2, based on either the first or second absolute pressure detection signal.

[0048] Depending on the specific application requirements, the second output terminal can be enabled or disabled. Specifically, when the second output terminal is enabled, it can output either the absolute pressure measurement value P1out representing the first fluid pressure P1 or the absolute pressure measurement value P2out representing the second fluid pressure P2. When the second output terminal is disabled, the pressure sensor does not provide any absolute pressure measurement results and can be used solely as a differential pressure sensor.

[0049] The first and second output terminals of the pressure sensor can be connected via external terminals 7 (see) provided on housing 1. Figure 1 )supply. Figure 8A One embodiment of the external terminal is shown. For example... Figure 8A As shown, the pressure sensor according to this disclosure may include three external terminals. Specifically, these three external terminals include a power supply terminal (i.e., power supply VCC), a ground terminal (i.e., ground GND), and an output terminal. The first and second output terminals of the pressure sensor are integrated into the output terminal.

[0050] Figure 8B Another implementation of the external terminal is shown. For example... Figure 8BAs shown, the pressure sensor according to this disclosure may include four external terminals. Specifically, these four external terminals include a power supply terminal (i.e., power supply VCC), a ground terminal (i.e., ground GND), a first output terminal, and a second output terminal. The first output terminal is used as a first output terminal of the pressure sensor to provide a differential pressure measurement value ΔPout representing the pressure difference between a first fluid pressure P1 and a second fluid pressure P2, and the second output terminal is used as a second output terminal of the pressure sensor to provide an absolute pressure measurement value P1out representing the first fluid pressure P1 or an absolute pressure measurement value P2out representing the second fluid pressure P2.

[0051] The pressure sensor described in this disclosure can be calibrated at the electronic assembly component level 2, the packaging module level 21, or the finished sensor product level. The specific calibration process is as follows: On a dedicated sensor calibration device, first, input the signal type, calibration temperature point, calibration pressure point, target pressure curve, and other parameter information required for the pressure sensor's output signal. Then, start the sensor calibration device to store the calibration temperature of the pressure sensor (electronic assembly component, packaging module, or finished sensor product, etc.). Subsequently, calibration pressure is simultaneously or separately applied to the first pressure port 9 and the second pressure port 10. The first absolute pressure sensing element 27 and the second absolute pressure sensing element 28 respectively detect the fluid pressure and generate a first absolute pressure detection signal and a second absolute pressure detection signal. The first and second absolute pressure detection signals are sent to the processing unit, which adjusts the signal amplification coefficient according to their respective set target values ​​and writes it in. Simultaneously, the differential pressure signal is calculated and compensated, thereby achieving calibration of the differential pressure signal at a specified temperature and pressure. For example, depending on the operating temperature range and operating pressure range of the pressure sensor, three or four calibration temperature points can be selected within the operating temperature range, and two or three calibration pressure points can be selected within the operating pressure range. By performing the calibration described above, the pressure sensor according to this disclosure can provide high-precision differential pressure measurements.

[0052] The pressure sensor described in this disclosure operates within a temperature range of -40°C to 150°C. Furthermore, those skilled in the art will understand that, depending on actual needs, the operating temperature range of the pressure sensor can be other suitable temperature ranges within the range of -40°C to 150°C. For example, the operating temperature range of the pressure sensor could be -40°C to 140°C.

[0053] The differential pressure measurement provided by the first output terminal of the pressure sensor according to this disclosure enables range calibration within the range of -200 kPa to 200 kPa, and the absolute pressure measurement provided by the second output terminal of the pressure sensor enables range calibration within the range of 0 to 220 kPa. Furthermore, those skilled in the art should understand that, depending on actual needs, the differential pressure measurement provided by the first output terminal of the pressure sensor can enable range calibration within a smaller pressure range of -200 kPa to 200 kPa, and the absolute pressure measurement provided by the second output terminal of the pressure sensor can enable range calibration within a smaller pressure range of 0 to 220 kPa. For example, the differential pressure measurement provided by the first output terminal of the pressure sensor can enable range calibration within the range of -20 kPa to 80 kPa, and the absolute pressure measurement provided by the second output terminal of the pressure sensor can enable range calibration within the range of 0 kPa to 100 kPa.

[0054] Although this disclosure has been described with reference to exemplary embodiments, it should be understood that this disclosure is not limited to the exemplary embodiments described above. Various variations and modifications can be made to the exemplary embodiments described above without departing from the scope and definition of this disclosure. The appended claims should be interpreted in the broadest possible sense to include all such variations and equivalent structures and functions.

Claims

1. A pressure sensor, characterized by, The pressure sensor comprises: a housing, in which a first pressure port and a second pressure port are provided and isolated from each other; and an electronic assembly component installed in the housing, the electronic assembly component comprising a first absolute pressure sensing element, a second absolute pressure sensing element and a processing unit, wherein the first absolute pressure sensing element is configured to detect a first fluid pressure in the first pressure port and generate a first absolute pressure detection signal, the second absolute pressure sensing element is configured to detect a second fluid pressure in the second pressure port and generate a second absolute pressure detection signal, and the processing unit comprises a first output end configured to provide a differential pressure measurement value representing a pressure difference between the first fluid pressure and the second fluid pressure based on the first absolute pressure detection signal and the second absolute pressure detection signal, and a second output end configured to provide an absolute pressure measurement value representing the first fluid pressure or the second fluid pressure based on the first absolute pressure detection signal or the second absolute pressure detection signal.

2. The pressure sensor of claim 1, wherein, The second output end can be enabled or disabled.

3. The pressure sensor of claim 2, wherein, The processing unit comprises a carrier, a packaging module and a circuit module, the packaging module and the circuit module being fixed to the carrier.

4. The pressure sensor of claim 3, wherein, The packaging module is a grid array packaging module, a BGA packaging module, a QFN packaging module or a QFP packaging module.

5. The pressure sensor of claim 3, wherein, The circuit module comprises a circuit board, the packaging module comprises a processing chip, the packaging module is electrically connected with the circuit board through a first electrical connection structure, the circuit board is electrically connected with an external terminal on the housing through a second electrical connection structure, and the first absolute pressure sensing element, the second absolute pressure sensing element and the processing chip are integrated in the packaging module.

6. The pressure sensor of claim 5, wherein, The circuit board is a printed circuit board or a flexible circuit board.

7. The pressure sensor of claim 5, wherein, The first electrical connection structure is a bonding wire, a surface mount, a soldering wire or a soldering strip.

8. The pressure sensor of claim 7, wherein, The second electrical connection structure is a crimping or soldering structure.

9. The pressure sensor of claim 2, wherein, The processing unit comprises a carrier, a printed circuit board and a ceramic plate arranged between the carrier and the printed circuit board, the printed circuit board comprises a processing chip, and the printed circuit board and the ceramic plate are fixed to the carrier.

10. The pressure sensor according to any one of claims 1 to 9, characterized in that, The working temperature range of the pressure sensor is -40°C to 150°C.

11. The pressure sensor according to any one of claims 1 to 9, characterized in that, The differential pressure measurement value provided by the first output end of the pressure sensor can achieve a range calibration in the range of -200kPa to 200kPa, and the absolute pressure measurement value provided by the second output end of the pressure sensor can achieve a range calibration in the range of 0 to 220kPa.

12. The pressure sensor of any one of claims 1 to 9, wherein, The pressure sensor comprises one output terminal, and the first output end and the second output end are integrated in the output terminal.

13. The pressure sensor of any one of claims 1 to 9, wherein, The pressure sensor comprises a first output terminal and a second output terminal, wherein the first output terminal is used as the first output end, and the second output terminal is used as the second output end.

14. The pressure sensor of any one of claims 1 to 9, wherein, The output forms of the differential pressure measurement value and the absolute pressure measurement value are analog signals or digital signals.

Images