Temperature pressure sensor

Abstract

The invention, which relates to the technical field of the sensor, discloses a temperature and pressure sensor comprising a detection housing, a temperature sensing unit, an annular ceramic capacitor, a signal processing unit and an electrical connection housing. Independent temperature and pressure detection channels are arranged in the detection shell to protect signals of the temperature sensing unit from being interfered by the annular ceramic capacitor, so that the stability of the temperature and pressure sensor is improved; the temperature sensing unit is connected with the signal processing unit through the axis through hole of the annular ceramic capacitor, wire winding is reduced, the assembling efficiency is improved, a disc-shaped assembly and redundant sealing rings are omitted, the overall structure of the temperature and pressure sensor is more compact, the height is reduced, the integration degree is further improved, automatic assembling and cost reduction are facilitated, and the temperature and pressure sensor is suitable for popularization and application. The problem that the structure of the temperature-pressure sensor is more complex due to the fact that the integration degree of the temperature and pressure sensing part of an existing temperature-pressure sensor is low is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of sensors, and in particular to a temperature and pressure sensor. Background Art

[0002] Temperature-pressure sensors are indispensable components in industrial automation, medical equipment and instruments, automobile manufacturing, the Internet of Things, and oil and gas transportation. In particular, the demand for these sensors in the automotive industry and industrial control is particularly significant, which has driven the expansion of the market.

[0003] With the technological advances in silicon, micromachining technology, ultra-large integrated circuit technology and special material preparation, pressure sensors have significantly improved in measurement accuracy, miniaturized size, temperature adaptability and stability in harsh environments; accordingly, temperature-pressure sensors are also developing towards miniaturization and high stability.

[0004] The current optimal structure of the temperature-pressure sensor is: a temperature sensing part, a pressure sensing part and a control processing part are arranged in sequence in the axial direction; in order not to affect the simultaneous detection of pressure and temperature, the detected liquid needs to be introduced into the reaction diaphragm of the pressure sensing part, so that the liquid pressure is sensed by the slight deformation of the reaction diaphragm, but it cannot affect the detection of the liquid temperature by the temperature sensing part, so the pressure and temperature detection channels must be separated; but because the pressure sensing part of the existing temperature-pressure sensor is a solid disc-shaped ceramic pressure capacitor, the wire of the front temperature sensing part needs to bypass the pressure sensing part before it can be connected to the control processing part. In order not to interfere with the liquid channel of the pressure sensing part and to protect the signal of the temperature sensing part, the structure of the existing temperature-pressure sensor is quite complicated, with many partition parts, many assembly steps and great assembly difficulty, resulting in low production efficiency and high cost.

[0005] For example, in the invention patent: CN108414030B, in order not to increase the volume of the temperature-pressure sensor and avoid affecting the performance of the ceramic capacitor, an eccentric capacitor is designed to drill holes around the capacitor to guide the wires of the temperature sensor part from the side to the control processing part, but the guided wires are soft. This design method makes it impossible to assemble the temperature-pressure sensor in an automated way, and it can only be assembled manually, which makes its manufacturing cost higher and its production efficiency lower than that of automated assembly. At the same time, the wires of the temperature sensing part will be longer and must withstand the interference of the pressure sensing part, which will increase the time consumption of the signal of the temperature sensing part during transmission and make it more susceptible to interference. In order to prevent the wires passing through the side from affecting the pressure channel of the pressure sensing part, a base and two sealing rings need to be added, which further increases the structural complexity of the temperature-pressure sensor and the production cost.

[0006] In summary, it is found that the prior art has at least the following technical problems: The existing temperature-pressure sensor is limited to the structure of the pressure sensing part, which makes the integration of the temperature and pressure sensing parts low, resulting in the problem that the structure of the temperature-pressure sensor is increasingly complicated. Summary of the invention

[0007] The object of the present invention is to provide a temperature-pressure sensor to solve the problem that the existing temperature-pressure sensor is limited to the structure of the pressure sensing part, resulting in a low integration of the temperature and pressure sensing parts, which leads to an increasingly complex structure of the temperature-pressure sensor.

[0008] The various technical effects that can be produced by the preferred technical solutions among the various technical solutions provided by the present invention are described in detail below.

[0009] In order to solve the above technical problems, the present invention provides the following technical solutions: The present invention provides a temperature and pressure sensor, comprising a detection shell, a temperature sensing unit, an annular ceramic capacitor, a signal processing unit and an electrical connection shell; the detection shell is provided with a temperature detection channel and a pressure detection channel which are independent of each other; the temperature detection channel surrounds the temperature sensing unit from the probe of the detection shell to the axial through hole of the annular ceramic capacitor, and is used to protect the electrical signal of the temperature sensing unit from being interfered by the annular ceramic capacitor; a shielding channel is provided on the axis of the detection shell, and the shielding channel communicates with the inner cavity of the probe and the axial through hole of the annular ceramic capacitor; the probe and the shielding channel constitute the temperature detection channel; the pressure detection channel comprises a guide hole and a pressure sensing cavity of an annular surface, and is used to introduce and temporarily store a pressure source medium; The guide hole introduces the pressure source medium to the end face of the reaction diaphragm of the annular ceramic capacitor for measuring pressure; the detection end of the temperature sensing unit extends into the probe; the reaction diaphragm of the annular ceramic capacitor is installed in the detection shell in the direction facing the inner end face of the detection shell; the signal processing unit is stacked and installed on the base of the annular ceramic capacitor and is electrically connected to the annular ceramic capacitor; the wire of the temperature sensing unit passes through the axial through hole of the annular ceramic capacitor to the signal processing unit and is electrically connected to the signal processing unit; the electrical connection shell is sealed and connected to the detection shell, and the pins of the electrical connection shell are electrically connected to the signal processing unit, which is used to provide signal transmission between the signal processing unit and external electrical components.

[0010] In one of the embodiments, the axes of the detection housing, the temperature sensing unit, the annular ceramic capacitor and the signal processing unit are all on the same axis.

[0011] In one embodiment, there is at least one flow-conducting hole.

[0012] In one of the embodiments, an inner ring sealing ring and an outer ring sealing ring are also installed in the detection housing, and the outer diameter of the inner ring sealing ring is smaller than the outer diameter of the outer ring sealing ring; the inner ring sealing ring surrounds the axial through hole of the reaction diaphragm, and the outer periphery of the reaction diaphragm surrounds the inner ring sealing ring, and the inner ring sealing ring and the outer ring sealing ring are both sealed and abutted against the reaction diaphragm and the inner end faces of the detection housing to form the pressure sensing chamber.

[0013] In one of the embodiments, the annular surface of the pressure sensing chamber at least covers the annular electrode of the annular ceramic capacitor.

[0014] In one embodiment, the detection shell includes a base shell and a mounting boss connected in sequence, the base shell is provided with a accommodating cavity, and the mounting boss is provided on the outer end surface of the base shell; the probe and the flow-conducting hole are both provided on the terminal end surface of the mounting boss; the pressure sensing cavity is provided in the accommodating cavity, and a fluid channel for transmitting a medium is provided between the flow-conducting hole and the pressure sensing cavity, and the flow-conducting hole, the pressure sensing cavity and the fluid channel constitute the pressure detection channel.

[0015] In one of the embodiments, an outer ring sealing groove and an inner ring sealing groove are provided on the end face of the accommodating cavity, the outer ring sealing ring is installed in the outer ring sealing groove, and the inner ring sealing ring is installed in the inner ring sealing groove; the shielding channel passes through the inner ring sealing groove.

[0016] In one embodiment, the detection housing is a metal component or a plastic component.

[0017] In one embodiment, the shielding channel includes a first channel and a second channel connected in sequence; the first channel is a section connecting the inner cavity of the probe to the end face of the accommodating cavity; the second channel is a section connecting the end face of the accommodating cavity to the axial through hole of the annular ceramic capacitor; the second channel is a tubular boss connected to the inner end face of the accommodating cavity, or a signal protection tube embedded in the first channel.

[0018] In one embodiment, the signal protection tube is a corrugated tube, a metal tube, a plastic tube or a ceramic tube with a metal cloth or metal mesh or metal foil on the peripheral wall, or a non-metallic tube with a conductive layer or microwave absorbing coating on the peripheral wall.

[0019] The beneficial effects of the present invention are as follows: First, by setting up independent temperature detection channels and pressure detection channels, physical isolation of the temperature sensing unit and the annular ceramic capacitor is achieved, thereby protecting the electrical signal of the temperature sensing unit from interference from the annular ceramic capacitor and improving the measurement accuracy and stability of the sensor.

[0020] Secondly, the design of the pressure detection channel allows the pressure measurement medium to directly enter the end face of the reaction diaphragm of the annular ceramic capacitor. By setting two sealing rings to close the inner through hole and outer ring of the annular reaction diaphragm, the gas, liquid and other media entering from the guide hole are sealed in the pressure sensing cavity of the annular surface, which simplifies the design of the liquid channel and prevents the leakage of the incoming liquid in a reliable medium sealing manner, thereby avoiding the short circuit problem of the temperature sensor or signal processing unit.

[0021] In addition, the temperature and pressure sensor of the present invention uses an annular ceramic capacitor, and through the axial through hole of the annular ceramic capacitor, the wire of the temperature sensing unit is conveniently assembled in a straight path, directly passes through the axial through hole of the annular ceramic capacitor to the signal processing unit, and is electrically connected to the signal processing unit; compared with the invention patent: CN108414030B, the structural components of the middle plate assembly or the disc assembly and the redundant sealing ring are reduced, the height of the temperature and pressure sensor is reduced, and the lightweight is further achieved, the application of the temperature and pressure sensor in small scenes is carried out, and the adaptability and flexibility of the sensor are enhanced.

[0022] The assembly process is also simplified. Compared with the invention patent: CN108414030B, it eliminates the "two process steps of bending the wires of the temperature sensing unit and bypassing them from the side of the disc-shaped ceramic capacitor;" thereby further reducing the manufacturing difficulty, further improving the assembly efficiency through automated assembly, and reducing the manufacturing cost of the temperature-pressure sensor.

[0023] In general, the present invention applies an annular ceramic capacitor as a pressure sensing unit and utilizes the axial through hole of the annular ceramic capacitor to enable the temperature detection channel to achieve a straight path from the probe of the detection shell to the signal processing unit, while achieving the optimized design of the temperature detection channel and the pressure detection channel, thereby improving the pressure perception sensitivity of the annular ceramic capacitor, the anti-interference performance of the temperature sensing unit, and shortening the signal transmission path of the temperature sensing unit, thereby achieving miniaturization, high stability and low-cost manufacturing of temperature and pressure sensors, and effectively solving the problems of low integration, complex structure, low production efficiency and high cost in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solution of the present invention, the drawings required for use in the implementation mode will be briefly introduced below. Obviously, the drawings described below are only some implementation modes of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0025] Figure 1 It is a schematic diagram of the axonometric structure of the temperature and pressure sensor of the present invention; Figure 2 1 is a schematic diagram of the structure of the temperature and pressure sensor of the present invention when viewed from above; Figure 3 It is a schematic cross-sectional view of the detection housing and the probe of the present invention; Figure 4 It is a schematic cross-sectional structure diagram of the entire temperature and pressure sensor of the present invention.

[0026] The reference numerals are as follows: 1. Detection housing; 11. Base housing; 12. Accommodation cavity; 121. Outer ring sealing groove; 122. Inner ring sealing groove; 13. Mounting boss; 131. Connecting thread; 2. Temperature detection channel; 21. Probe; 22. Shielding channel; 221. First channel; 222. Second channel; 3. Pressure detection channel; 31. Diversion hole; 32. Fluid channel; 321. First flow channel; 322. Second flow channel; 33. Pressure sensing chamber; 4. Temperature sensing unit; 5. Ring-shaped ceramic capacitor; 51. Base; 52. Reaction diaphragm; 53. Axial through hole; 6. Signal processing unit; 7. Electrical connection shell; 81. Inner ring sealing ring; 82. Outer ring sealing ring; 83. External sealing ring. DETAILED DESCRIPTION

[0027] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0028] A temperature and pressure sensor is provided in a specific embodiment, which effectively solves the problem that the existing temperature-pressure sensor is limited to the structure of the pressure sensing part, resulting in low integration of the temperature and pressure sensing parts, and causing the structure of the temperature-pressure sensor to become increasingly complex.

[0029] In addition, all the contents of the configurations shown in the following embodiments are not necessarily limited to the solutions of the inventions described in the claims.

[0030] A first embodiment of a temperature and pressure sensor is Figures 1 to 4 As shown, it includes a detection shell 1, a temperature sensing unit 4, an annular ceramic capacitor 5, a signal processing unit 6 and an electrical connection shell 7; the detection shell 1 is provided with a temperature detection channel 2 and a pressure detection channel 3 which are independent of each other; the temperature detection channel 2 surrounds the temperature sensing unit 4 from the probe 21 of the detection shell 1 to the axial through hole 53 of the annular ceramic capacitor 5, and is used to protect the electrical signal of the temperature sensing unit 4 from interference from the annular ceramic capacitor 5; a shielding channel 22 is provided on the axis of the detection shell 1, and the shielding channel 22 communicates with the inner cavity of the probe 21 and the axial through hole 53 of the annular ceramic capacitor 5; the probe 21 and the shielding channel 22 constitute the temperature detection channel 2; the pressure detection channel 3 includes a guide hole 31 and a pressure sensing cavity 33 of an annular surface, which is used to introduce and temporarily store the pressure source medium ; The guide hole 31 introduces the pressure source medium to the end face of the reaction diaphragm 52 of the annular ceramic capacitor 5 for measuring pressure; the detection end of the temperature sensing unit 4 extends into the probe 21; the reaction diaphragm 52 of the annular ceramic capacitor 5 is installed in the detection shell 1 in the direction facing the inner end face of the detection shell 1; the signal processing unit 6 is stacked and installed on the base 51 of the annular ceramic capacitor 5 and is electrically connected to the annular ceramic capacitor 5; the wire of the temperature sensing unit 4 passes through the axial through hole 53 of the annular ceramic capacitor 5 to the signal processing unit 6, and is electrically connected to the signal processing unit 6; the electrical connection shell 7 is sealed and connected to the detection shell 1, and the pins of the electrical connection shell 7 are electrically connected to the signal processing unit 6, which is used to provide signal transmission between the signal processing unit 6 and external electrical components.

[0031] The axes of the detection housing 1 , the temperature sensing unit 4 , the annular ceramic capacitor 5 and the signal processing unit 6 are all on the same axis.

[0032] The temperature and pressure sensor of the present invention uses an annular ceramic capacitor 5. Through the axial through hole 53 of the annular ceramic capacitor 5, the wire of the temperature sensing unit 4 is conveniently assembled in a straight path, directly passes through the axial through hole 53 of the annular ceramic capacitor 5 to the signal processing unit 6, and is electrically connected to the signal processing unit 6; compared with the invention patent: CN108414030B, the structural components of the middle plate component or the disc-mounted component and the redundant sealing ring are reduced, the height of the temperature and pressure sensor is reduced, and the lightweight is further achieved, the application of the temperature and pressure sensor in small scenes is carried out, and the adaptability and flexibility of the sensor are enhanced.

[0033] The assembly process is also simplified. Compared with the invention patent: CN108414030B, it eliminates "the two process steps of bending the wire of the temperature sensing unit 4 and bypassing it from the side of the disc-shaped ceramic capacitor;" thereby further reducing the manufacturing difficulty, further improving the assembly efficiency through automated assembly, and reducing the manufacturing cost of the temperature-pressure sensor.

[0034] As one optional implementation, Regarding the specific structure of the above-mentioned detection housing, the specific structure of the temperature detection channel 2 and the pressure detection channel 3, as shown in FIG. Figure 3 and Figure 4 As shown, the detection shell 1 includes a base shell 11 and a mounting boss 13 connected in sequence, the base shell 11 is provided with a accommodating cavity 12, and the mounting boss 13 is arranged on the outer end surface of the base shell 11; a probe 21 and a flow guide hole 31 are arranged on the terminal end surface of the mounting boss 13; a shielding channel 22 is arranged on the axis of the base shell 11 and the mounting boss 13, and the shielding channel 22 connects the inner cavity of the probe 21 and the axial through hole 53 of the annular ceramic capacitor 5; the probe 21 and the shielding channel 22 constitute a temperature detection channel 2; the pressure sensing cavity 33 is arranged in the accommodating cavity 12, and a fluid channel 32 for transmitting a medium is arranged between the flow guide hole 31 and the pressure sensing cavity 33, and the flow guide hole 31, the pressure sensing cavity 33 and the fluid channel 32 constitute a pressure detection channel 3.

[0035] The specific structure of the fluid channel, such as Figure 3 and Figure 4 As shown, the fluid channel 32 includes a first flow channel 321 and a second flow channel 322 . The first flow channel 321 is provided from the mounting boss 13 to the base shell 11 , and the second flow channel 322 is provided in the base shell 11 and is located under the pressure sensing chamber 33 .

[0036] Regarding the arrangement of the above-mentioned flow-conducting holes, at least one flow-conducting hole 31 is provided.

[0037] When applying, Figure 3 and Figure 4 As shown, the flow guide hole 31 is set next to the probe 21, and two flow guide holes 31 are set, which are symmetrically arranged, and can guide gas, liquid and other media into the pressure sensing chamber 33 at the same time. When the monitored liquid pressure changes, the liquid pressure in the two flow guide holes 31 also changes at the same time. The symmetrical pressure change gives the reaction diaphragm 52 a symmetrical and uniform force. Therefore, under the influence of the structure of the pressure detection channel 3 set in the shell, the pressure change monitored by the internally installed pressure sensing unit is also more accurate, and the output pressure information has higher accuracy.

[0038] Regarding the specific structure of the above-mentioned shielding channel, such as Figure 3 As shown, the shielding channel 22 includes a first channel 221 and a second channel 222 connected in sequence; the first channel 221 is a section connecting the inner cavity of the probe 21 to the end face of the accommodating cavity 12; the second channel 222 is a section connecting the end face of the accommodating cavity 12 to the axial through hole 53 of the annular ceramic capacitor 5; the second channel 222 is a tubular boss connected to the inner end face of the accommodating cavity 12, or a signal protection tube embedded in the first channel 221.

[0039] The detection housing 1 is a metal component or a plastic component. That is, the second channel 222 is a tubular boss connected to the inner end surface of the accommodating cavity 12 and is a structure manufactured integrally with the base housing 11 .

[0040] In further application, the signal protection tube can also be a corrugated tube, a metal tube, a plastic tube, a plastic tube or a ceramic tube with a metal cloth or a metal mesh or a metal foil on the peripheral wall, or a non-metallic tube with a conductive layer or a microwave absorbing coating on the peripheral wall. By isolating or absorbing the electrical signal around the annular ceramic capacitor 5, the signal transmitted by the temperature sensing unit 4 is protected from interference.

[0041] Regarding the sealing structure forming the pressure sensing cavity, Figure 4 As shown, an inner ring sealing ring 81 and an outer ring sealing ring 82 are also installed in the detection shell 1. The outer diameter of the inner ring sealing ring 81 is smaller than the outer diameter of the outer ring sealing ring 82. The inner ring sealing ring 81 surrounds the axial through hole 53 of the reaction diaphragm 52, and the outer periphery of the reaction diaphragm 52 surrounds the inner ring sealing ring 81. The inner ring sealing ring 81 and the outer ring sealing ring 82 are both sealed against the reaction diaphragm 52 and the inner end surface of the detection shell 1 to form a pressure sensing chamber 33.

[0042] Specifically, Figure 3 As shown, the inner ring seal ring 81 and the outer ring seal ring 82 cooperate with the base shell 11, and the end surface of the accommodating cavity 12 is provided with an outer ring seal groove 121 and an inner ring seal groove 122, the outer ring seal ring 82 is installed in the outer ring seal groove 121, and the inner ring seal ring 81 is installed in the inner ring seal groove 122; the shielding channel 22 passes through the inner ring seal groove 122. The shielding channel 22 contacts the inner cavity of the inner ring seal ring 81.

[0043] Furthermore, the annular surface of the pressure sensing cavity 33 at least covers the annular electrode of the annular ceramic capacitor 5. The annular ceramic capacitor 5 detects pressure information through the reaction diaphragm 52 when it is impacted by pressure of gas, liquid, etc., the reaction diaphragm 52 is deformed, the distance between the electrode of the annular ceramic base 51 and the electrode of the annular reaction diaphragm 52 changes, so that the capacitance of the annular ceramic capacitor 5 changes, the annular ceramic capacitor 5 outputs real-time capacitance, and the capacitance difference is calculated and converted into a pressure signal, thereby realizing the perception of pressure; the pressure sensing cavity 33 is a pressure source that provides pressure to the reaction diaphragm 52, and the area of ​​the pressure sensing cavity 33 determines the force area of ​​the reaction diaphragm 52, and also affects the deformation of the reaction diaphragm 52; when the area of ​​the pressure sensing cavity 33 is smaller than the annular electrode area of ​​the annular ceramic capacitor 5, it will cause the capacitance change between the electrodes to be smaller than the normal value, thereby causing the pressure detection of the annular ceramic capacitor 5 to deviate.

[0044] The temperature and pressure sensor of the present invention realizes physical isolation of the temperature sensing unit 4 and the annular ceramic capacitor 5 by setting up a temperature detection channel 2 and a pressure detection channel 3 which are independent of each other, thereby protecting the electrical signal of the temperature sensing unit 4 from interference from the annular ceramic capacitor 5 and improving the measurement accuracy and stability of the sensor.

[0045] Secondly, the design of the pressure detection channel 3 allows the pressure measurement medium to directly enter the end face of the reaction diaphragm 52 of the annular ceramic capacitor 5. By setting two sealing rings to close the inner through hole and the outer ring of the annular reaction diaphragm 52, the gas, liquid and other media entering from the guide hole 31 are sealed in the pressure sensing cavity 33 of the annular surface, which simplifies the design of the liquid channel and prevents the leakage of the incoming liquid in a reliable medium sealing manner, thereby avoiding the short circuit problem of the temperature sensor or the signal processing unit 6.

[0046] In general, the present invention uses an annular ceramic capacitor 5 as a pressure sensing unit and utilizes the axial through hole 53 of the annular ceramic capacitor to enable the temperature detection channel 2 to achieve a straight path from the probe of the detection shell 1 to the signal processing unit 6, while achieving the optimized design of the temperature detection channel 2 and the pressure detection channel 3, thereby improving the pressure sensing sensitivity of the annular ceramic capacitor 5, the anti-interference performance of the temperature sensing unit 4, and shortening the signal transmission path of the temperature sensing unit 4, thereby achieving miniaturization, high stability and low-cost manufacturing of the temperature and pressure sensors, and effectively solving the problems of low integration, complex structure, low production efficiency and high cost in the prior art.

[0047] Regarding the installation structure of the temperature and pressure sensor when in use, such as Figure 1 As shown, a connecting thread 131 is provided on the circumference of the end of the mounting boss 13 ; an external sealing ring 83 is installed on the circumferential surface of the mounting boss 13 , and the external sealing ring 83 is arranged between the connecting thread 131 and the outer end surface of the base shell 11 .

[0048] Regarding the specific connection structure of the above-mentioned signal processing unit, the signal processing unit 6 is a PCB control board, and the PCB control board is provided with pinholes connected to the pins of the annular ceramic capacitor 5 and solder joints connected to the temperature sensing unit 4; the pins provided on the back side of the base 51 of the annular ceramic capacitor 5 are inserted into the pinholes and welded; the wires of the temperature sensing unit 4 are welded and connected to the solder joints.

[0049] When applying, the connection method of pinholes and solder points can make the connection between the signal processing unit 6 (PCB control board) and other sensor units more standardized and modular, which is conducive to the design and implementation of automated assembly lines, thereby improving the overall assembly efficiency.

[0050] When designing the automated welding steps, the annular ceramic capacitor 5, the temperature sensor unit 4 and the signal processing unit 6 can be integrated into a welding jig, and then the entire jig can be combined with a welding process such as reflow soldering or wave soldering to achieve high mechanical stability of the automated welding connection and optimize component production.

[0051] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described.

Claims

1. A temperature and pressure sensor, It is characterized in that It includes a detection shell, a temperature sensing unit, a ring-shaped ceramic capacitor, a signal processing unit and an electrical connection shell; the detection shell is provided with a temperature detection channel and a pressure detection channel which are independent of each other; The temperature detection channel surrounds the temperature sensing unit from the probe of the detection housing to the axial through hole of the annular ceramic capacitor, and is used to protect the electrical signal of the temperature sensing unit from interference by the annular ceramic capacitor; A shielding channel is provided on the axis of the detection housing, and the shielding channel communicates with the inner cavity of the probe and the axial through hole of the annular ceramic capacitor; the probe and the shielding channel constitute the temperature detection channel; The pressure detection channel includes a guide hole and a pressure sensing cavity on an annular surface, which are used to introduce and temporarily store the pressure source medium; the guide hole introduces the pressure source medium to the end surface of the reaction diaphragm of the annular ceramic capacitor, which is used to measure the pressure; The detection end of the temperature sensing unit extends into the probe; the reaction diaphragm of the annular ceramic capacitor is installed in the detection shell in a direction facing the inner end surface of the detection shell; the signal processing unit is stacked and installed on the base of the annular ceramic capacitor and is electrically connected to the annular ceramic capacitor; the wire of the temperature sensing unit passes through the axial through hole of the annular ceramic capacitor to the signal processing unit and is electrically connected to the signal processing unit; The electrical connection shell is sealed and connected to the detection housing, and the pins of the electrical connection shell are electrically connected to the signal processing unit, so as to provide signal transmission between the signal processing unit and external electrical components.

2. The temperature and pressure sensor according to claim 1, It is characterized in that The axes of the detection housing, the temperature sensing unit, the annular ceramic capacitor and the signal processing unit are all on the same axis.

3. The temperature and pressure sensor according to claim 1, It is characterized in that The guide hole is provided with at least one.

4. The temperature and pressure sensor according to claim 2, It is characterized in that An inner ring sealing ring and an outer ring sealing ring are also installed in the detection shell, and the outer diameter of the inner ring sealing ring is smaller than the outer diameter of the outer ring sealing ring; the inner ring sealing ring surrounds the axial through hole of the reaction diaphragm, and the outer periphery of the reaction diaphragm surrounds the inner ring sealing ring, and the inner ring sealing ring and the outer ring sealing ring are both sealed and abutted against the reaction diaphragm and the inner end surface of the detection shell to form the pressure sensing chamber.

5. The temperature and pressure sensor according to claim 4, It is characterized in that The annular surface of the pressure sensing cavity at least covers the annular electrode of the annular ceramic capacitor.

6. The temperature and pressure sensor according to claim 4, It is characterized in that The detection shell includes a base shell and a mounting boss connected in sequence, the base shell is provided with a accommodating cavity, and the mounting boss is provided on the outer end surface of the base shell; the probe and the flow-conducting hole are both provided on the terminal end surface of the mounting boss; the pressure sensing cavity is provided in the accommodating cavity, and a fluid channel for transmitting a medium is provided between the flow-conducting hole and the pressure sensing cavity, and the flow-conducting hole, the pressure sensing cavity and the fluid channel constitute the pressure detection channel.

7. The temperature and pressure sensor according to claim 6, It is characterized in that An outer ring sealing groove and an inner ring sealing groove are provided on the end surface of the accommodating cavity, the outer ring sealing ring is installed in the outer ring sealing groove, and the inner ring sealing ring is installed in the inner ring sealing groove; The shielding channel passes through the inner ring sealing groove.

8. The temperature and pressure sensor according to claim 6, It is characterized in that The detection housing is a metal component or a plastic component.

9. The temperature and pressure sensor according to claim 8, It is characterized in that The shielding channel includes a first channel and a second channel connected in sequence; the first channel is a section connecting the inner cavity of the probe to the end face of the accommodating cavity; the second channel is a section connecting the end face of the accommodating cavity to the axial through hole of the annular ceramic capacitor; the second channel is a tubular boss connected to the inner end face of the accommodating cavity, or a signal protection tube embedded in the first channel.

10. The temperature and pressure sensor according to claim 9, It is characterized in that The signal protection tube is a corrugated tube, a metal tube, a plastic tube or a ceramic tube with a metal cloth or a metal mesh or a metal foil on the peripheral wall, or a non-metal tube with a conductive layer or a microwave absorbing coating on the peripheral wall.

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