Passive wireless tire pressure sensor

Abstract

The invention provides a passive wireless tire pressure sensor which comprises a sensor shell, a temperature and pressure sensitive assembly, a circuit board and an antenna board, the circuit board is electrically connected with the temperature and pressure sensitive assembly and the antenna board, and the circuit board is used for transmitting electric energy to the temperature and pressure sensitive assembly and processing temperature and pressure data output by the temperature and pressure sensitive assembly. The antenna board is used for providing electric energy for the temperature and pressure sensitive assembly and wirelessly sending the temperature and pressure data output by the circuit board to an external device. According to the passive wireless tire pressure sensor, the tire pressure and the tire temperature can be transmitted to the external equipment in a wireless mode so as to achieve wireless transmission, wireless radio frequency energy can be converted into direct current to provide electric energy for the temperature and pressure sensitive assembly so as to achieve passive power supply, and compared with the prior art, the passive wireless tire pressure sensor has the advantages of being simple in structure and convenient to use. The arrangement of a battery and a power supply cable is reduced, and the weight of the sensor is reduced, so that the sensor is light; meanwhile, the battery can be prevented from high-temperature burning explosion and the like, and the safety of the sensor is improved.

Description

Technical Field

[0001] The embodiments of the present disclosure belong to the field of sensor technology, and particularly relate to a passive wireless tire pressure sensor. Background Art

[0002] In the field of aircraft tire pressure and temperature monitoring, manual presses installed on the wheel valves are typically used for testing. This method has significant drawbacks: The valve assembly must be disassembled, which can easily cause tire leaks and increase maintenance burdens; the testing process is time-consuming and labor-intensive, affecting pre-flight preparation efficiency; and simultaneous temperature monitoring is impossible.

[0003] Related technologies also use sensors for detection. Wireless tire pressure sensors often rely on batteries or external power supplies, posing safety risks such as battery failure at low temperatures and explosion at high temperatures. The additional power lines also increase the weight and wiring complexity of onboard equipment. Therefore, a passive, power-free, lightweight, highly sealed, and fully domestically produced wireless tire pressure sensing solution is urgently needed to meet the requirements of high aircraft safety, weight reduction, and autonomous control. Summary of the Invention

[0004] The embodiments of the present disclosure aim to solve at least one of the technical problems existing in the prior art and provide a passive wireless tire pressure sensor.

[0005] An embodiment of the present disclosure provides a passive wireless tire pressure sensor, comprising:

[0006] A sensor housing, the sensor housing having a receiving cavity and an air inlet, the air inlet being communicated with the receiving cavity;

[0007] a temperature and pressure sensitive component, the temperature and pressure sensitive component being disposed in the accommodating cavity, the temperature and pressure sensitive component comprising a temperature and pressure sensing end and a communication transmission end, the temperature and pressure sensing end being close to the air inlet;

[0008] A circuit board, the circuit board is arranged in the accommodating cavity, the circuit board is arranged on a side of the temperature and pressure sensitive component away from the temperature and pressure sensing end, the circuit board is electrically connected to the communication transmission end, the circuit board is used to transmit power to the temperature and pressure sensitive component and to process the temperature and pressure data output by the temperature and pressure sensitive component;

[0009] An antenna board is arranged in the accommodating cavity, and the antenna board is arranged on the side of the circuit board away from the temperature and pressure sensitive component. The antenna board is electrically connected to the circuit board, and the antenna board is used to provide power to the temperature and pressure sensitive component and to wirelessly send the temperature and pressure data output by the circuit board to an external device.

[0010] In some embodiments of the present disclosure, the antenna board includes:

[0011] A passive energy harvesting unit, the passive energy harvesting unit is used to receive space wireless radio frequency energy and output direct current to the circuit board;

[0012] The radio frequency signal transmission unit is used to receive external wireless instructions and wirelessly send the temperature and pressure signals transmitted by the circuit board to external equipment.

[0013] In some embodiments of the present disclosure, the passive energy harvesting unit includes: a first LC resonant antenna, a rectification and filtering module, and an LDO voltage regulator module. The first LC resonant antenna is used to receive spatial wireless RF energy and form a DC current to output to the rectification and filtering module. The rectification and filtering module is used to rectify and filter the DC current. The LDO voltage regulator module is used to stabilize the DC current after rectification and filtering and output 3.3V standard DC power to the circuit board.

[0014] In some embodiments of the present disclosure, the radio frequency signal transmission unit includes: a second LC resonant antenna, a downlink controller, an IIC data interface, an uplink controller and a third LC resonant antenna, the second LC resonant antenna is used to receive a wireless signal from an external device and transmit it to the downlink controller, the downlink controller is used to control the IIC data interface to output an inquiry instruction to the circuit board according to the wireless signal, the IIC data interface is used to upload the temperature and pressure data of the circuit board to the uplink controller, the uplink controller is used to transfer the temperature and pressure data to the third LC resonant antenna, and the third LC resonant antenna is used to wirelessly transmit the temperature and pressure data to the external device.

[0015] In some embodiments of the present disclosure, the circuit board includes an electric energy processing module, a compensation amplification module and a conditioning output module. The electric energy processing module is used to process the electric energy output by the antenna board and output a constant current of 2.5V DC to the temperature and pressure sensitive component. The compensation amplification module is used to compensate and amplify the temperature and pressure signal output by the temperature and pressure sensitive component and transmit it to the conditioning output module. The conditioning output module is used to output the compensated and amplified temperature and pressure signal to the antenna board.

[0016] In some embodiments of the present disclosure, the temperature and pressure sensitive component includes: a temperature and pressure sensitive base, a temperature and pressure chip, a metal diaphragm and a chip pin. The temperature and pressure sensitive base is connected to the inner wall of the sensor housing, the temperature and pressure chip is embedded in the end face of the temperature and pressure sensitive base close to the air inlet, the metal diaphragm is arranged on the side of the temperature and pressure sensitive base close to the air inlet, the space between the metal diaphragm and the temperature and pressure sensitive base is filled with silicone oil, and the chip pin connects the temperature and pressure chip and the circuit board.

[0017] In some embodiments of the present disclosure, the temperature and pressure sensitive chip comprises a temperature sensitive chip and a pressure sensitive chip, and the temperature sensitive chip is embedded in the end face of the temperature and pressure sensitive base in a spaced manner with the pressure sensitive chip.

[0018] In some embodiments of the present disclosure, the passive wireless tire pressure sensor comprises a conversion plate arranged on the side of the temperature and pressure sensitive assembly away from the air inlet, and the chip pin is fixedly connected with the conversion plate.

[0019] In some embodiments of the present disclosure, the air inlet of the sensor shell comprises at least two air inlet holes, and the at least two air inlet holes are arranged in a spaced manner along the circumference of the end face of the sensor shell.

[0020] In some embodiments of the present disclosure, the sensor shell comprises a shell body and a shell cover, the shell body is detachably connected with the shell cover, and the air inlet is arranged at one end of the shell body away from the shell cover.

[0021] The passive wireless tire pressure sensor according to the embodiments of the present disclosure comprises a sensor shell, a temperature and pressure sensitive assembly, a circuit board and an antenna plate, wherein the temperature and pressure sensitive assembly, the circuit board and the antenna plate are arranged in a containing cavity in the interior of the sensor shell, specifically, the temperature and pressure sensitive assembly is used for sensing the tire pressure and the tire temperature of an aviation tire and transmitting the tire pressure and the tire temperature data to the circuit board, the circuit board processes the tire temperature and the tire pressure data and transmits the tire temperature and the tire pressure data to the antenna plate, so as to wirelessly transmit the tire pressure and the tire temperature data to an external device through the antenna plate; the antenna plate can also convert the wireless radio frequency energy into direct current, and transmit the direct current to the temperature and pressure sensitive assembly through the circuit board, so as to provide the temperature and pressure sensitive assembly with electric energy. The passive wireless tire pressure sensor according to the embodiments of the present disclosure can realize wireless transmission of the tire pressure and the tire temperature to an external device, and can also realize conversion of the wireless radio frequency energy into direct current to provide the temperature and pressure sensitive assembly with electric energy, so as to realize passive power supply. Compared with the prior art, the passive wireless tire pressure sensor reduces the setting of the battery and the power cable, reduces the weight of the sensor, and realizes light weight of the sensor; at the same time, the use of the battery is reduced, and the safety problems such as high-temperature explosion of the battery can be prevented, and the safety of the sensor is improved. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 FIG. 1 is a schematic view of a passive wireless tire pressure sensor according to an embodiment of the present disclosure;

[0023] Figure 2 FIG. 2 is a working principle diagram of the passive wireless tire pressure sensor shown in FIG. 1. Figure 1

[0024] In the drawings, various reference numerals represent the following:

[0025] ​100. Passive wireless tire pressure sensor;

[0026] 10. Sensor housing; 11. Housing body; 111. First housing; 112. Second housing; 12. Housing cover; 101. Air inlet;

[0027] 20. Temperature and pressure sensitive components; 21. Temperature and pressure sensitive base; 22. Temperature sensitive chip; 23. Pressure sensitive chip; 24. Metal diaphragm; 25. Chip pins; 26. Silicone oil;

[0028] 30. Circuit board; 31. Power processing module; 32. Compensation amplification module; 33. Conditioning output module;

[0029] 40. Antenna board; 41. Passive energy harvesting unit; 411. First LC resonant antenna; 412. Rectifier and filter module; 413. LDO voltage regulator module; 42. RF signal transmission unit; 421. Second LC resonant antenna; 422. Downlink controller; 423. IIC data interface; 424. Uplink controller; 425. Third LC resonant antenna;

[0030] 50. Adapter plate;

[0031] 60, FR-1 wire;

[0032] 70. RF cables;

[0033] 81. End seal; 82. Side seal;

[0034] 90. Bracket stud. DETAILED DESCRIPTION

[0035] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments described herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0036] It should be understood that the terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting.

[0037] The singular forms "a," "an," and "the" may also be construed to include the plural forms. The terms "comprise," "include," "contain," and "have" are inclusive and, therefore, specify the presence of the stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The control method steps, processes, and operations described herein are not to be construed as necessarily requiring them to be performed in the particular order described or illustrated, unless an order of execution is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0038] Although the terms first, second, third, etc. can be used in the text to describe multiple elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can only be used to distinguish an element, component, region, layer or section from another region, layer or section. Unless the context clearly indicates otherwise, terms such as "first", "second" and other numerical terms do not imply order or sequence when used in the text. Therefore, the first element, component, region, layer or section discussed below can be referred to as the second element, component, region, layer or section without departing from the teaching of the example embodiments.

[0039] For ease of description, spatially relative terms may be used herein to describe the relationship of one element or feature relative to another element or feature as shown in the figures, such as "inside," "outside," "inside," "outside," "below," "beneath," "above," and the like. Such spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is flipped, an element described as "below" or "below" another element or feature would then be oriented as "above" or "above" another element or feature. Thus, the example term "below" can include both above and below orientations. The device may be otherwise oriented (rotated 90 degrees or in other orientations) and the spatially relative descriptors used herein are interpreted accordingly.

[0040] like Figure 1As shown, an embodiment of the present disclosure provides a passive wireless tire pressure sensor 100, which includes: a sensor housing 10, a temperature and pressure sensitive component 20, a circuit board 30 and an antenna board 40. Specifically, the sensor housing 10 has a receiving cavity and an air inlet 101, the air inlet 101 is connected to the receiving cavity, the temperature and pressure sensitive component 20 is arranged in the receiving cavity and the temperature and pressure sensitive component 20 is connected to the inner wall of the sensor housing 10, the temperature and pressure sensitive component 20 has a temperature and pressure sensing end and a communication transmission end, the temperature and pressure sensing end is close to the air inlet 101, and the circuit board 30 is arranged In the accommodating cavity, the circuit board 30 is arranged on the side of the temperature and pressure sensitive component 20 away from the temperature and pressure sensing end, the circuit board 30 is electrically connected to the communication transmission end, the circuit board 30 is used to transmit electrical energy to the temperature and pressure sensitive component 20 and to process the temperature and pressure data output by the temperature and pressure sensitive component 20, the antenna board 40 is arranged in the accommodating cavity, the antenna board 40 is arranged on the side of the circuit board 30 away from the temperature and pressure sensitive component 20, the antenna board 40 is electrically connected to the circuit board 30, the antenna board 40 is used to provide electrical energy to the temperature and pressure sensitive component 20 and to wirelessly send the temperature and pressure data output by the circuit board 30 to an external device.

[0041] According to the passive wireless tire pressure sensor 100 of the embodiment of the present disclosure, it includes a sensor housing 10, a temperature and pressure sensitive component 20, a circuit board 30 and an antenna board 40, wherein the temperature and pressure sensitive component 20, the circuit board 30 and the antenna board 40 are all arranged in an internal accommodating cavity of the sensor housing 10. Specifically, the temperature and pressure sensitive component 20 is used to sense the tire pressure and tire temperature of the aircraft tire, and transmit the tire pressure and tire temperature data to the circuit board 30. The circuit board 30 processes the tire temperature and tire pressure data and transmits them to the antenna board 40, so as to wirelessly transmit the tire pressure and tire temperature data to an external device through the antenna board 40; the antenna board 40 can also convert space wireless radio frequency energy into direct current, and transmit the direct current to the temperature and pressure sensitive component 20 through the circuit board 30, thereby providing power for the temperature and pressure sensitive component 20. The passive wireless tire pressure sensor 100 of the embodiment of the present disclosure can transmit tire pressure and tire temperature to an external device wirelessly to achieve wireless transmission, and can also convert wireless radio frequency energy into direct current to provide power for the temperature and pressure sensitive component 20 to achieve passive power supply. Compared with the existing technology, the setting of batteries and power cables is reduced, and the weight of the sensor is reduced, so that the sensor is lightweight; at the same time, the use of batteries is reduced, and safety issues such as high-temperature explosion of batteries can be prevented, thereby improving the safety of the sensor.

[0042] In some embodiments of the present disclosure, the air inlet 101 of the sensor housing 10 includes at least two air inlet holes, spaced apart along the circumference of the sensor housing 10 on the end surface of the sensor housing 10, each air inlet hole communicating with the accommodating cavity. Specifically, the sensor housing 10 has an axisymmetric structure, and the at least two air inlet holes are arranged symmetrically along the axis of symmetry of the sensor housing 10 on the end surface of the sensor housing 10. There are four air inlet holes, symmetrically arranged about the axis of symmetry, and each has a diameter of 1.2 mm.

[0043] In some embodiments of the present disclosure, the sensor housing 10 includes a housing body 11 and a housing cover 12. The housing body 11 and the housing cover 12 are detachably connected, forming a receiving chamber. The air inlet 101 is located at the end of the housing body 11 facing away from the housing cover 12. Specifically, the housing body 11 and the housing cover 12 are both axisymmetric. The detachable connection between the housing body 11 and the housing cover 12 facilitates the installation of components such as the temperature and pressure sensing assembly 20, the adapter plate 50, the circuit board 30, and the antenna board 40 within the sensor housing 10, thereby improving the installation efficiency of the passive wireless tire pressure sensor 100. The housing body 11 and the housing cover 12 can be detachably connected using various methods, such as threaded, snap-fit, or plug-in connections. The housing body 11 and the housing cover 12 are sealed to prevent external dust and other substances from entering the interior of the sensor housing 10, thereby preventing dust from contaminating the components within the sensor housing 10 and improving the detection accuracy of the passive wireless tire pressure sensor 100.

[0044] Furthermore, the housing body 11 includes a first housing 111 and a second housing 112. The first housing 111 and the second housing 112 are welded together to form the integral housing body 11. The second housing 112 is threadedly connected to the housing cover 12. The width of the weld between the first and second housings 111 and 112 is 0.4 to 0.6 mm, and the depth of the weld is 0.5 to 0.6 mm. The housing cover 12 is made of fiberglass reinforced plastic, which has a certain strength and rigidity and is also wave-transmissive.

[0045] An end face seal 81 is further provided on the end face of one end of the air inlet 101 of the housing body 11, and a side seal 82 is further provided on the peripheral side of the housing body 11. The end face seal 81 and the side seal 82 ensure the sealing reliability of the connection between the sensor housing 10 and the wheel hub.

[0046] In some embodiments of the present disclosure, the temperature and pressure sensitive component 20 includes: a temperature and pressure sensitive base 21, which is connected to the inner wall of the sensor housing 10 along the circumference of the shell body 11. Specifically, the temperature and pressure sensitive base 21 is welded to the first shell 111 of the shell body 11, and the weld width is 0.5 to 0.8 mm, the weld depth is 1 to 1.5 mm, and the weld is free of cracks when observed under a microscope.

[0047] The temperature and pressure sensitive component 20 includes: a temperature and pressure chip, which is embedded in the end face of the temperature and pressure sensitive base 21 near the air inlet 101. Specifically, the temperature and pressure chip includes a temperature sensitive chip 22 and a pressure sensitive chip 23. The temperature sensitive chip 22 and the pressure sensitive chip 23 are spaced apart and arranged at the end face of the temperature and pressure sensitive base 21, and the temperature sensitive chip 22 and the pressure sensitive chip 23 are respectively embedded in the interior of the temperature and pressure sensitive base 21. Furthermore, the end face of the temperature sensitive chip 22 is flush with the end face of the temperature and pressure sensitive base 21, and the end face of the pressure sensitive chip 23 is flush with the end face of the temperature and pressure sensitive base 21, so as to improve the firmness of the temperature sensitive chip 22 and the pressure sensitive chip 23. The pressure sensitive chip 23 and the temperature sensitive chip 22 can be embedded in the temperature and pressure sensitive base 21 by bonding, so as to further improve the reliability of the connection between the temperature sensitive chip and the temperature and pressure sensitive base 21.

[0048] The temperature and pressure sensitive component 20 includes: a metal diaphragm 24, which is connected to the inner wall of the first shell 111 of the shell body 11, and the metal diaphragm 24 is arranged on the side of the temperature and pressure sensitive base 21 close to the air inlet 101. The metal diaphragm 24 and the temperature and pressure sensitive base 21 are spaced apart, and a liquid-filled space is formed between the metal diaphragm 24, the temperature and pressure sensitive base 21, and the first shell 111. Silicone oil 26 is filled in the liquid-filled space between the metal diaphragm 24, the temperature and pressure sensitive base 21, and the first shell 111.

[0049] The temperature and pressure sensitive component 20 includes chip pins 25 that connect the temperature and pressure chip to the circuit board 30. Specifically, the temperature sensitive chip 22 is connected to the circuit board 30 via two chip pins 25, and the pressure sensitive chip 23 is connected to the circuit board 30 via two chip pins 25.

[0050] In some embodiments of the present disclosure, the passive wireless tire pressure sensor 100 includes an adapter plate 50, which is disposed on the side of the temperature and pressure sensing assembly 20 facing away from the air inlet 101. The chip pins 25 are fixedly connected to the adapter plate 50. Specifically, the adapter plate 50 is disposed on the end of the temperature and pressure sensing base 21 facing away from the air inlet 101. The adapter plate 50 is welded to the chip pins 25, which are then connected to the circuit board 30 after passing through the adapter plate 50.

[0051] In some embodiments of the present disclosure, a passive wireless tire pressure sensor 100 includes an FR-1 wire 60 and a radio frequency cable 70. The FR-1 wire 60 connects the chip pins 25 and the circuit board 30 to achieve electrical connection between the chip pins 25 and the circuit board 30. The radio frequency cable 70 connects the circuit board 30 and the antenna board 40 to achieve electrical connection between the circuit board 30 and the antenna board 40. Along the direction from the air inlet 101 of the sensor housing 10 to the housing cover 12 of the sensor housing 10, the temperature and pressure sensitive component 20, the circuit board 30, and the antenna board 40 are arranged in sequence, wherein the temperature and pressure sensitive component 20 and the circuit board 30 are connected via the FR-1 wire 60, and the circuit board 30 and the antenna board 40 are connected via the radio frequency cable 70. Specifically, the circuit board 30 is connected to the first shell 111 of the housing body 11 via a bracket stud 90, and the antenna board 40 is connected to the bracket stud 90 via a cross-recessed flat head screw. Thread fastener is applied to the screw threads to achieve a thread loosening effect.

[0052] In some embodiments of the present disclosure, the antenna board 40 includes: a passive energy harvesting unit 41 and a radio frequency signal transmission unit 32, the passive energy harvesting unit 41 is used to receive wireless radio frequency energy in space and output direct current to the circuit board 30; the radio frequency signal transmission unit 32 is used to receive external wireless instructions and wirelessly send the temperature and pressure signals transmitted by the circuit board 30 to external devices.

[0053] In some embodiments of the present disclosure, the passive energy harvesting unit 41 includes: a first LC resonant antenna 411, a rectification and filtering module 412 and an LDO voltage regulator module 413. The first LC resonant antenna 411 is used to receive spatial wireless RF energy and form a DC current to output to the rectification and filtering module 412. The rectification and filtering module 412 is used to rectify and filter the DC current. The LDO voltage regulator module 413 is used to stabilize the DC current after rectification and filtering and output 3.3V standard DC power to the circuit board 30.

[0054] In some embodiments of the present disclosure, the RF signal transmission unit 42 includes: a second LC resonant antenna 421, a downlink controller 422, an IIC data interface 423, an uplink controller 424 and a third LC resonant antenna 425. The second LC resonant antenna 421 is used to receive wireless signals from external devices and transmit them to the downlink controller 422. The downlink controller 422 is used to control the IIC data interface 423 to output an inquiry instruction to the circuit board 30 according to the wireless signal. The IIC data interface 423 is used to upload the temperature and pressure data of the circuit board 30 to the uplink controller 424. The uplink controller 424 is used to transfer the temperature and pressure data to the third LC resonant antenna 425. The third LC resonant antenna 425 is used to wirelessly transmit the temperature and pressure data to the external device.

[0055] In some embodiments of the present disclosure, the circuit board 30 comprises an electric energy processing module 31, a compensation amplification module 32 and a conditioning output module 33, the electric energy processing module 31 is used to process the electric energy output by the antenna board 40 and output a constant current 2.5V direct current to the temperature and pressure sensitive component 20, the compensation amplification module 32 is used to compensate and amplify the temperature and pressure signal output by the temperature and pressure sensitive component 20 and transmit to the conditioning output module 33, and the conditioning output module 33 is used to output the compensated and amplified temperature and pressure signal to the antenna board 40.

[0056] Electric energy collection and supply process:

[0057] The first LC resonant antenna 411 receives the space wireless radio frequency energy, forms a direct current, and outputs a 3.3V standard direct current through the rectification and filtering module 412 and the LDO voltage stabilizing module 413. The 3.3V standard direct current supplies power to the electric energy processing module 31 of the rear-end circuit board 30, i.e. supplies power to the electric energy processing module 31 of the conditioning chip, and the electric energy processing module 31 of the conditioning chip outputs a constant current 2.5V direct current to supply power to the temperature and pressure chip of the temperature and pressure sensitive component 20.

[0058] Radio frequency signal transmission process:

[0059] After the temperature and pressure sensitive component 20 works, the temperature and pressure chip outputs the internal medium pressure signal and temperature signal of the aircraft tire, the compensation amplification module 32 of the conditioning chip performs compensation amplification processing on the pressure signal and temperature signal, the second LC resonant antenna 421 receives the external wireless instruction, outputs the inquiry instruction through the IIC data interface of the radio frequency circuit downlink controller 422, uploads the compensated and amplified pressure signal and temperature signal to the uplink controller 424 through the radio frequency circuit IIC data interface 423, and finally the pressure signal and temperature signal detected by the temperature and pressure sensitive component 20 are sent to the rear-end signal collection device in a wireless form through the third LC resonant antenna 425.

[0060] It can be understood that the above embodiments are only exemplary embodiments adopted for illustrating the principles of the present disclosure, however, the present disclosure is not limited thereto. Various modifications and improvements can be made by those of ordinary skill in the art without departing from the spirit and essence of the present disclosure, and these modifications and improvements are also regarded as the protection scope of the present disclosure.

Claims

1. A passive wireless tire pressure sensor, characterized in that: The passive wireless tire pressure sensor includes: A sensor housing, the sensor housing having a receiving cavity and an air inlet, the air inlet being communicated with the receiving cavity; a temperature and pressure sensitive component, the temperature and pressure sensitive component being disposed in the accommodating cavity, the temperature and pressure sensitive component comprising a temperature and pressure sensing end and a communication transmission end, the temperature and pressure sensing end being close to the air inlet; A circuit board, the circuit board is arranged in the accommodating cavity, the circuit board is arranged on a side of the temperature and pressure sensitive component away from the temperature and pressure sensing end, the circuit board is electrically connected to the communication transmission end, the circuit board is used to transmit power to the temperature and pressure sensitive component and to process the temperature and pressure data output by the temperature and pressure sensitive component; An antenna board is arranged in the accommodating cavity, and the antenna board is arranged on the side of the circuit board away from the temperature and pressure sensitive component. The antenna board is electrically connected to the circuit board, and the antenna board is used to provide power to the temperature and pressure sensitive component and to wirelessly send the temperature and pressure data output by the circuit board to an external device.

2. The passive wireless tire pressure sensor according to claim 1, characterized in that: The antenna board includes: A passive energy harvesting unit, the passive energy harvesting unit is used to receive space wireless radio frequency energy and output direct current to the circuit board; The radio frequency signal transmission unit is used to receive external wireless instructions and wirelessly send the temperature and pressure signals transmitted by the circuit board to external equipment.

3. The passive wireless tire pressure sensor according to claim 2, characterized in that: The passive energy collection unit includes: a first LC resonant antenna, a rectification and filtering module and an LDO voltage regulator module. The first LC resonant antenna is used to receive spatial wireless RF energy and form a DC current to output to the rectification and filtering module. The rectification and filtering module is used to rectify and filter the DC current. The LDO voltage regulator module is used to stabilize the DC current after rectification and filtering and output 3.3V standard DC power to the circuit board.

4. The passive wireless tire pressure sensor according to claim 2, characterized in that: The radio frequency signal transmission unit includes: a second LC resonant antenna, a downlink controller, an IIC data interface, an uplink controller and a third LC resonant antenna, wherein the second LC resonant antenna is used to receive a wireless signal from an external device and transmit it to the downlink controller, the downlink controller is used to control the IIC data interface to output an inquiry instruction to the circuit board according to the wireless signal, the IIC data interface is used to upload the temperature and pressure data of the circuit board to the uplink controller, the uplink controller is used to transfer the temperature and pressure data to the third LC resonant antenna, and the third LC resonant antenna is used to wirelessly transmit the temperature and pressure data to the external device.

5. The passive wireless tire pressure sensor according to claim 1, characterized in that: The circuit board includes an electric energy processing module, a compensation amplification module and a conditioning output module. The electric energy processing module is used to process the electric energy output by the antenna board and output a constant current of 2.5V DC to the temperature and pressure sensitive component. The compensation amplification module is used to compensate and amplify the temperature and pressure signal output by the temperature and pressure sensitive component and transmit it to the conditioning output module. The conditioning output module is used to output the compensated and amplified temperature and pressure signal to the antenna board.

6. The passive wireless tire pressure sensor according to claim 1, characterized in that: The temperature and pressure sensitive component includes: a temperature and pressure sensitive base, a temperature and pressure chip, a metal diaphragm and chip pins. The temperature and pressure sensitive base is connected to the inner wall of the sensor housing, the temperature and pressure chip is embedded in the end face of the temperature and pressure sensitive base close to the air inlet, the metal diaphragm is arranged on the side of the temperature and pressure sensitive base close to the air inlet, the space between the metal diaphragm and the temperature and pressure sensitive base is filled with silicone oil, and the chip pins connect the temperature and pressure chip and the circuit board.

7. The passive wireless tire pressure sensor according to claim 6, characterized in that: The temperature and pressure chip includes a temperature sensitive chip and a pressure sensitive chip. The temperature sensitive chip and the pressure sensitive chip are embedded in the end surface of the temperature and pressure sensitive base at intervals.

8. The passive wireless tire pressure sensor according to claim 6, characterized in that: The passive wireless tire pressure sensor includes an adapter plate, which is arranged on a side of the temperature and pressure sensitive component away from the air inlet, and the chip pins are fixedly connected to the adapter plate.

9. The passive wireless tire pressure sensor according to claim 1, characterized in that: The air inlet of the sensor housing includes at least two air inlet holes, and the at least two air inlet holes are arranged on the end surface of the sensor housing at intervals along the circumference of the sensor housing.

10. The passive wireless tire pressure sensor according to claim 1, characterized in that: The sensor housing comprises a housing body and a housing cover. The housing body and the housing cover are detachably connected. The air inlet is arranged at one end of the housing body away from the housing cover.

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