Temperature and pressure composite sensor

Abstract

The invention belongs to the field of sensors, and particularly relates to a temperature and pressure composite sensor. The sensor comprises a shell, a sensitive assembly arranged in a base and a temperature probe, wherein a heat conduction groove is formed in the end of the temperature probe and used for measuring the liquid temperature. The circuit board is divided into a lower-layer conversion circuit board, a middle-layer pressure circuit board and an upper-layer temperature circuit board, the lower layer is fixed on the base through screws, the upper layer and the middle layer are fixed through copper columns and screws, and fixing holes are arranged beside the circuit. The outer side of the sensor is provided with a sealing groove and a flange structure, the lower end is sealed by a sealing ring and compressed by a middle flange, and the head is provided with a socket connected with an upper computer to transmit parameters. Compared with a traditional sensor, the temperature probe retracts inwards, so that the structure is compact, small space is adapted, the stability is enhanced by combining a multi-layer circuit board fixing mode with sealing and a flange structure, and the precision is improved by optimizing the measurement process through the pressure sensing through hole and the heat conduction groove. The scheme can solve the problems of long temperature probe, complex structure and the like of a traditional sensor.

Description

Technical Field

[0001] The invention belongs to the field of sensors, in particular to a temperature-pressure composite sensor. Background Art

[0002] The temperature and pressure composite sensor is a sensor that can measure two physical quantities, temperature and pressure, at the same time. It plays a key role in many fields such as industrial automation, automobile manufacturing, aerospace, and environmental monitoring. In the industrial production process, the temperature and pressure composite sensor can be used to monitor the temperature and pressure of the fluid in the pipeline to ensure the safety and stability of the production process. In the automobile engine system, it can measure the temperature and pressure in the cylinder in real time, providing key data for engine control and optimization.

[0003] In the field of sensor technology, traditional temperature and pressure composite sensors have many shortcomings. From the structural point of view, such as CN221549754U Figure 1 As shown in the figure, the temperature probe usually needs to be extended longer, which makes the overall structure of the sensor larger. In some application scenarios with strict space requirements, it will take up too much space, which is not conducive to the miniaturization and integration of the equipment. In terms of installation, traditional sensors need to use circuit board brackets to install circuit boards. This installation method not only takes up more control structure space, but also reduces the strength of the overall structure to a certain extent due to the existence of the bracket structure, so that the stability and reliability of the sensor are affected when facing external force impact or vibration. In addition, the overall structure of the traditional temperature and pressure composite sensor is relatively complex, with numerous components and complex connection relationships, which not only increases the difficulty and cost of production and manufacturing, but may also affect the performance of the sensor due to coordination problems between components, such as the stability and accuracy of signal transmission. Summary of the invention

[0004] In order to solve the problem that the temperature probe of the traditional temperature-pressure composite sensor is long and has a complex structure, the present invention proposes a temperature-pressure composite sensor, in which the sensitive component and the temperature probe are placed in a base, the multi-layer circuit board is specifically fixed, and the outside is connected by a flange to solve the above technical problems.

[0005] In order to achieve the above objectives, the present invention specifically adopts the following technical solutions:

[0006] A temperature-pressure composite sensor comprises a shell, a temperature probe, a sensitive component and a circuit board installed inside the shell, wherein the sensitive component is connected to the circuit board for measuring pressure values, the temperature probe is used to measure temperature signals and transmit them upwards, a pressure inlet head is arranged below the sensitive component, a pressure-sensing through hole is arranged inside the pressure inlet head, the sensitive component converts the measurement parameters into electrical signals through the circuit board, and transmits the pressure signal upwards step by step, and the sensitive component and the temperature probe are arranged inside the base.

[0007] Furthermore, the pressure-sensitive through hole is used for pressure gas or liquid to flow so as to contact the sensitive component, and the sensitive component transmits the measured pressure parameter to the circuit board.

[0008] Furthermore, the temperature probe contains a temperature sensitive element, and the end of the temperature probe is a heat conduction groove, which is connected to the device under test for measuring the temperature of the liquid.

[0009] Furthermore, the circuit board includes a lower conversion circuit board, a middle pressure circuit board and an upper temperature circuit board. The lower circuit board is fixed to the base by screws, and the upper and middle circuit boards are fixed by copper columns and screws.

[0010] Furthermore, a sealing groove and a flange structure are provided on the outer side of the sensor, and the lower end of the sensor is sealed by a sealing ring and is pressed and fixed by an intermediate flange structure.

[0011] Furthermore, the sensor head also includes a socket, which is used to connect to a host computer and transmit the measured parameters to the host computer.

[0012] Furthermore, a fixing hole is provided on the side of the circuit, a screw is installed on the upper circuit board, a copper column is installed on the middle circuit board, and the screw and the copper column are connected by threads so as to fix the upper and middle circuit boards to each other.

[0013] Compared with the prior art, the present invention has the following beneficial technical effects:

[0014] The temperature probe is placed inside the base, which changes the situation that the traditional sensor has a large appearance due to the long extension of the probe. In actual application scenarios, such as when the internal space of electronic equipment is limited, this compact structural design can be easily adapted, reducing the demand for installation space, improving the space utilization of the equipment, and providing strong support for the miniaturization of equipment.

[0015] The multi-layer circuit board adopts a unique fixing method. The lower layer is fixed to the base with screws, and the upper and middle layers are fixed by copper columns and screws. Combined with the sealing groove and flange structure on the outside of the sensor, the lower end is sealed by a sealing ring and pressed by the middle flange. The above structural design can effectively prevent the loosening of the circuit board and the displacement of components in the face of complex environments such as mechanical vibration and temperature changes, ensuring the stability of the internal structure of the sensor, thereby ensuring the stability and reliability of the measurement data, which is significantly enhanced in terms of stability compared to traditional sensors.

[0016] The pressure-sensitive through hole inside the pressure inlet head provides a stable flow channel for pressurized gas or liquid, allowing the sensitive component to accurately contact the medium for pressure measurement; the heat conduction groove at the end of the temperature probe is tightly connected to the device under test, and the temperature sensitive element inside it can efficiently sense the temperature. The above design optimizes the measurement process from the measurement principle and structure, reduces measurement errors, effectively improves the accuracy of pressure and temperature measurement, and meets the needs of application scenarios with high measurement accuracy requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural appearance diagram of a specific embodiment of the present invention;

[0018] Figure 2 It is a structural appearance diagram of a specific embodiment of the present invention from another viewing angle;

[0019] Figure 3 is a partial cross-sectional view of a specific embodiment of the present invention;

[0020] Figure 4 It is a cross-sectional view of a specific embodiment of the present invention.

[0021] Numbers in the figure:

[0022] 1. Shell; 101. Socket; 2. Base; 201. Sealing groove; 202. Flange structure; 3. Circuit board; 301. Temperature circuit board; 302. Pressure circuit board; 303. Adjustment circuit board; 4. Pressure inlet head; 401. Pressure sensing through hole; 5. Temperature probe; 501. Heat conduction groove; 6. Screws; 7. Copper column; 8. Sensitive component. DETAILED DESCRIPTION

[0023] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, 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. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0024] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, the omission of certain well-known structures and their descriptions in the drawings is understandable.

[0025] See also Figure 1and 2 , the cylindrical design of the bottom seal of the housing 1 fits tightly with the detection port of the engine. Before installation, ensure that the surface of the engine detection port is flat and free of impurities to ensure good contact between the sensor and the detection port. During installation, carefully insert the sensor into the detection port so that the bottom of the housing 1 is aligned with the edge of the detection port. Then, use the sealing groove 201 and flange structure 202 on the outside of the sensor to fix it. Place a suitable sealing ring in the sealing groove 201. Usually, a rubber sealing ring that is resistant to high temperature, corrosion and has good elasticity is selected to ensure the sealing between the sensor and the detection port under the high temperature and high pressure environment of the engine. Then, the intermediate flange structure 202 is tightly connected to the corresponding flange of the engine detection port by bolts. When tightening the bolts, it is necessary to operate according to the specified torque value to ensure the firmness of the connection and prevent the sensor from loosening or displacement due to vibration or pressure changes during engine operation. ,

[0026] After installation, the socket 101 on the sensor head is connected to the engine's electronic control unit (ECU) through a dedicated cable. The cable should be selected based on its high temperature resistance and anti-interference performance to ensure the stability of signal transmission. When connecting, ensure that the cable plug fits tightly with the socket 101. The connection terminals inside the socket 101 should have good conductivity and stability to reliably transmit the temperature and pressure signals measured by the sensor. After the connection is completed, the cable should be properly fixed and protected to avoid cable damage or loose connection due to engine vibration or other external factors.

[0027] See also Figure 3 The lubricating oil or gas and other pressure media inside the engine first contacts the pressure inlet head 4, ensuring that it can receive pressure from different parts inside the engine. The pressure-sensing through hole 401 inside it provides a channel for pressure transmission. The aperture size of the pressure-sensing through hole 401 is designed according to the pressure variation range inside the engine and the sensitivity of the sensitive component 8. The inner wall is finely processed and has a high degree of smoothness to reduce energy loss and turbulence during pressure transmission, ensuring that the pressure can be stably and accurately transmitted to the sensitive component 8.

[0028] After receiving the pressure, the pressure sensitive element in the sensitive component 8 will deform based on its specific physical principle. Taking the common piezoresistive sensitive element as an example, the crystal structure of the semiconductor material inside it will change under the pressure, resulting in a change in resistance. This change in resistance is detected and converted by the circuit on the circuit board 3. The lower conversion circuit board 303 of the circuit board 3 will perform preliminary processing on the weak electrical signal from the sensitive component 8. First, the signal is amplified by a low-noise amplifier to increase the amplitude of the signal so that it can be accurately identified and processed by subsequent circuits. At the same time, a filtering circuit is used to remove high-frequency noise and interference components in the signal, and the signal after preliminary processing is transmitted to the middle-layer pressure circuit board 302.

[0029] The middle layer pressure circuit board 302 further amplifies and calibrates the signal accurately. Under different operating conditions of the engine, such as idling, acceleration, high-speed operation, etc., the pressure change range and characteristics will be different. The pressure circuit board 302 can automatically identify these operating conditions and adjust the signal processing parameters to ensure that the output pressure signal accurately reflects the actual pressure inside the engine. The processed pressure signal is transmitted to the socket 101 through the circuit board 3, and finally stably transmitted to the engine's ECU.

[0030] See also Figure 4 The heat conducting groove 501 at the end of the temperature probe 5 is closely attached to the cylinder wall, lubricating oil channel or other key parts of the engine. During the operation of the engine, the high temperature generated by the combustion in the cylinder and the temperature change of the lubricating oil will be quickly transmitted to the temperature sensitive element inside the temperature probe 5 through the heat conducting groove 501. The temperature sensitive element will convert this thermoelectric potential into a weak electrical signal.

[0031] The upper temperature circuit board 301 will perform a series of processing operations on the temperature signal. First, linearization processing is performed. Since the thermoelectric potential and temperature of the thermocouple are not a simple linear relationship, the temperature circuit board 301 has a built-in linearization algorithm. By fitting and compensating the thermoelectric potential and temperature relationship curve, the thermoelectric potential is accurately converted into a corresponding temperature value. At the same time, changes in the ambient temperature of the engine may affect the cold end temperature of the temperature probe 5, thereby introducing measurement errors. In this embodiment, the temperature circuit board 301 also has a cold end compensation function. By measuring the cold end temperature and using the pre-stored temperature compensation coefficient and algorithm, the measurement result is corrected to eliminate the influence of the cold end temperature change on the measurement accuracy, ensuring that the output temperature signal is accurate and reliable. The processed temperature signal is also transmitted to the socket 101 through the circuit board 3, and then transmitted to the engine's ECU.

[0032] The multi-layer circuit board structure of the sensor remains stable throughout the entire operating cycle of the engine. The lower circuit board 303 is firmly fixed to the base 2 by screws 6, providing a foundation for the entire circuit board system. The upper and middle circuit boards are fixed by the tight fit of copper pillars 7 and screws 6, as well as the auxiliary fixing holes on the side of the circuit to ensure that the circuit boards will not loosen or move in the vibration environment of the engine. The above design can maintain the stability of signal transmission. For example, when the engine is running at high speed, it will generate large vibrations and impact forces, but the sensor's circuit board can still work stably to ensure the continuous and accurate transmission of measurement data.

[0033] As the engine continues to run, the sensor needs to be regularly maintained and calibrated. During the maintenance process, the technician will first check whether the housing 1 is damaged, such as whether there is deformation or cracks in the housing caused by engine vibration or other reasons. At the same time, the cable connection will be checked to see if it is loose, ensuring that the signal transmission line between the sensor and the ECU is unobstructed. For calibration work, high-precision pressure and temperature standard equipment is required. When the engine is stopped, connect the standard pressure source and temperature source to the sensor, and adjust the pressure and temperature measurement accuracy of the sensor according to the prescribed calibration procedure. For example, by adjusting the relevant circuit parameters on the circuit board 3, such as gain, zero offset, etc., the measurement results of the sensor are matched with the measurement values ​​of the standard equipment, ensuring that the sensor can continue to provide accurate and reliable temperature and pressure data during the subsequent engine operation.

[0034] In summary, the present invention innovates the original sensor structure, reduces the outer dimensions and size of the sensor, simplifies the structure, and improves the stability and reliability of internal components, thereby forming a new temperature and pressure composite sensor with high precision, good stability, and easy installation and carrying.

Claims

1. A temperature-pressure composite sensor, comprising a housing (1), a temperature probe (5), a sensitive component (8), and a circuit board (3) installed inside the housing (1), wherein the sensitive component (8) is connected to the circuit board (3) for measuring a pressure value, the temperature probe (5) is used to measure a temperature signal and transmit it upward, a pressure inlet head (4) is arranged below the sensitive component (8), a pressure-sensing through hole (401) is provided inside the pressure inlet head (4), the sensitive component (8) converts a measurement parameter into an electrical signal through the circuit board (3), and transmits the pressure signal upward step by step, characterized in that: The sensitive component (8) and the temperature probe (5) are arranged inside the base (2).

2. The temperature-pressure composite sensor according to claim 1, characterized in that: The pressure-sensitive through hole (401) is used for the flow of pressurized gas or liquid so as to contact the sensitive component (8), and the sensitive component (8) transmits the measured pressure parameter to the circuit board (3).

3. The temperature-pressure composite sensor according to claim 1, characterized in that: The temperature probe (5) contains a temperature sensitive element inside, and the end of the temperature probe (5) is a heat conducting groove (501), and the heat conducting groove (501) is connected to the device under test for measuring the temperature of the liquid.

4. The temperature-pressure composite sensor according to claim 1, characterized in that: The circuit board (3) comprises a lower conversion circuit board (303), a middle pressure circuit board (302) and an upper temperature circuit board (301); the lower circuit board (303) is fixed to the base (2) by screws (6), and the upper and middle circuit boards are fixed by copper pillars (7) and screws (6).

5. The temperature-pressure composite sensor according to claim 1, characterized in that: A sealing groove (201) and a flange structure (202) are provided on the outside of the sensor, and the lower end of the sensor is sealed by a sealing ring and is pressed and fixed by the middle flange structure (202).

6. The temperature-pressure composite sensor according to claim 1, characterized in that: The sensor head also includes a socket (101), and the socket (101) is used to connect to a host computer and transmit measured parameters to the host computer.

7. The temperature-pressure composite sensor according to claim 4, characterized in that: A fixing hole is provided on the side of the circuit, a screw (6) is installed on the upper circuit board, a copper column (7) is installed on the middle circuit board, and the screw (6) and the copper column (7) are connected by threads so as to fix the upper and middle circuit boards to each other.

Images