A self-powered wireless transmission type tensile and compressive magnetostrictive force sensor

Abstract

The present invention discloses a self-powered wireless transmission type tensile and compressive magnetostrictive force sensor, which relates to the field of magnetostrictive force sensors. It includes: an installation cavity is formed by enclosing between the inner wall of the barrel wall, the pressure ring and the lower end shaft; the input shaft passes through the pressure ring and is arranged at the top opening of the barrel wall and is connected to the connecting shaft; an upper piezoelectric ceramic ring is arranged between the input shaft and the piezoelectric ceramic ring partition plate, and a lower piezoelectric ceramic ring is arranged between the connecting shaft and the piezoelectric ceramic ring partition plate; an upper permanent magnet is arranged at the groove between the fixed frame end cover and the fixed frame, a magnetostrictive rod is arranged in the inner cavity of the fixed frame, an upper magnetic conductive sheet and a pre-tightening spring are arranged at the upper end of the magnetostrictive rod, and a lower magnetic conductive sheet is arranged at the lower end; a lower permanent magnet is sleeved on the lower permanent magnet baffle; an energy collection module and a data acquisition and wireless radio frequency transmission and output module are arranged in the barrel wall. The present invention helps to achieve self-power supply of the device, real-time tracking of the force conditions of each aircraft rotor and its pitch link, and reduction of maintenance costs.

Description

Technical Field

[0001] The present invention relates to the technical field of magnetostrictive force sensors, and in particular to a self-powered wireless transmission type tensile-compressive magnetostrictive force sensor. Background Art

[0002] During the high-speed flight of a helicopter, sharp maneuvering flight can cause serious structural stress on the propeller pitch link. If the stress is too large, accidents will occur. For the load monitoring of the rotor pitch rod, a new rotor pitch rod load monitoring sensor system is required.

[0003] The traditional power supply method is to use chemical batteries to provide energy. Wireless sensors that require long-term energy supply need to replace the batteries regularly, which not only brings a lot of inconvenience and economic burden to the wireless sensors but also causes environmental pollution. The inherent disadvantages of chemical batteries limit the application of portable electronic devices and wireless sensors and become one of the bottlenecks in their development. Mechanical vibration is ubiquitous in nature and has a high energy density, making energy harvesters based on mechanical vibration have the advantages of long-term power supply and being less restricted by weather and application scenarios, thus increasingly becoming a research field that has received much attention. Piezoelectric energy harvesters have the advantages of simple structure, high energy density, long life, and compatibility with MEMS.

[0004] As a core component in the monitoring, diagnosis, and intelligent control system, the performance of the sensor directly determines the quality of the test results and affects the final diagnosis conclusion. Therefore, any sensor first needs to meet the requirements of sensitivity and linearity. In addition, once the structure of the sensor is too complex and the working conditions are harsh, its stability will be reduced and it is prone to failure; at this time, a sensor that is easy to disassemble and assemble can shorten the maintenance period and reduce economic losses. Therefore, current sensors are all developing in the direction of simple structure and wireless testing. The magnetostrictive effect and its inverse effect can realize the mutual conversion of magnetic energy and mechanical energy.

[0005] For information transmission and collection systems, the traditional method is to use a wired connection method, which limits the number of layout lines and occupies a large space. Currently, with the rapid development of wireless layout methods, more and more systems use wireless methods.

[0006] Therefore, how to provide a self-powered wireless transmission type tensile-compressive magnetostrictive force sensor with the effects of simple structure, real-time perception, fast response, and high stability is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0007] In view of this, the present invention provides a self-powered wireless transmission type tensile and compressive magnetostrictive force sensor, which can achieve the self-powered function of the sensor and can monitor the stress and strain of the aircraft rotor in real time. To achieve the above object, the present invention adopts the following technical solutions:

[0008] A self-powered wireless transmission type tensile and compressive magnetostrictive force sensor, comprising:

[0009] A barrel wall, a pressure ring and a lower end shaft, and an installation cavity is formed by enclosing between the inner wall of the barrel wall, the pressure ring and the lower end shaft;

[0010] An input shaft passes through the pressure ring and is arranged at the top opening of the barrel wall;

[0011] An upper piezoelectric ceramic ring plate and a lower piezoelectric ceramic ring plate are sequentially arranged from top to bottom between the input shaft and the connecting shaft, and a piezoelectric ceramic ring plate partition is arranged between the upper piezoelectric ceramic ring plate and the lower piezoelectric ceramic ring plate;

[0012] An upper permanent magnet is arranged between the fixed frame end cover and the upper end of the fixed frame. A magnetostrictive rod is arranged in the inner cavity of the fixed frame. A slot is opened on one side of the fixed frame for pasting a Hall element at the slot of the fixed frame so as to make it contact the magnetostrictive rod. Upper and lower magnetic conductive sheets are respectively arranged at the upper and lower ends of the magnetostrictive rod;

[0013] A pre-tightening spring is installed between the upper magnetic conductive sheet and the connecting shaft;

[0014] The lower end of the fixed frame is connected to the lower permanent magnet, and the position of the lower permanent magnet is fixed by a lower permanent magnet baffle;

[0015] A chip end cover and a chip barrel wall are arranged in the space enclosed by the lower permanent magnet baffle, the barrel wall and the lower end shaft. An energy harvesting module and a data acquisition and wireless radio frequency transmitting and outputting module are arranged between the chip end cover and the chip barrel wall.

[0016] For the above sensor, optionally, the pressure ring and the barrel wall are connected by threads to fix the position of the piezoelectric ceramic ring plate partition;

[0017] The input shaft and the connecting shaft are connected by threads. The upper piezoelectric ceramic ring plate and the lower piezoelectric ceramic ring plate are sleeved on the connecting shaft, and the upper piezoelectric ceramic ring plate and the lower piezoelectric ceramic ring plate are separated by a piezoelectric ceramic ring plate partition;

[0018] In addition, two symmetrical through holes are provided on the piezoelectric ceramic ring plate partition for the leads of the upper piezoelectric ceramic ring plate and the lower piezoelectric ceramic ring plate to access the subsequent circuit through the through holes.

[0019] For the above sensor, optionally, the inner diameter of the pressure ring matches the outer diameter of the retaining ring of the input shaft, the upper end of the pressure ring is lower than the upper end of the input shaft, and in addition, a sealant is used for sealing treatment between the two.

[0020] For the above-mentioned sensor, optionally, the inner diameters of the upper piezoelectric ceramic ring, the lower piezoelectric ceramic ring, the inner diameter of the piezoelectric ceramic ring partition and the outer diameter of the threaded hole of the connecting shaft are equal.

[0021] The outer diameter of the inner cavity of the fixing bracket is equal to the inner diameter of the upper permanent magnet, the outer diameter of the upper ring of the fixing bracket is equal to the outer diameter of the upper permanent magnet, the fixing bracket end cover is connected to the fixing bracket, the outer diameter of the lower end of the fixing bracket, the outer diameter of the lower permanent magnet and the outer diameter of the upper permanent magnet are equal, and the lower permanent magnet is sleeved on the lower permanent magnet baffle. The diameter of the lower end of the lower permanent magnet baffle is equal to the inner diameter of the barrel wall, and two symmetrical through holes are drilled.

[0022] The diameters of the upper magnetic conductive sheet, the lower magnetic conductive sheet, the magnetostrictive rod, the outer diameter of the pre-tightening spring are equal to the inner diameter of the groove of the lower permanent magnet baffle.

[0023] For the above-mentioned sensor, optionally, the lower surface of the fixing bracket and the upper surface of the lower permanent magnet, the lower surface of the lower permanent magnet and the upper surface of the lower permanent magnet baffle are adhesively bonded.

[0024] For the above-mentioned sensor, optionally, the height of the upper magnetic conductive sheet is lower than the height of the upper permanent magnet, and the height of the lower magnetic conductive sheet is higher than the height of the lower permanent magnet.

[0025] The upper magnetic conductive sheet is arranged on the top surface of the magnetostrictive rod, and the lower magnetic conductive sheet is arranged on the bottom surface, which is used to guide the magnetic flux of the upper permanent magnet and the lower permanent magnet.

[0026] For the above-mentioned sensor, optionally, the polarities of the opposite surfaces of the upper permanent magnet and the lower permanent magnet are opposite, which is used to apply a bias magnetic field to the magnetostrictive rod.

[0027] For the above-mentioned sensor, optionally, the chip end cover and the lower permanent magnet baffle are connected by countersunk head screws, the chip barrel wall and the lower end shaft are connected by countersunk head screws, the chip end cover and the chip barrel wall are threadedly connected, and a through hole is left at the chip barrel wall.

[0028] For the above-mentioned sensor, optionally, the lower permanent magnet baffle is threadedly connected to the inner side of the barrel wall, the lower end shaft is threadedly connected to the inner side of the barrel wall, and a retaining ring is arranged on the lower end shaft, which is closely attached to the bottom of the barrel wall to prevent the lower end shaft from having an interference fit when screwing into the inner side of the barrel wall, so as to realize the limit of the lower end shaft and the lower permanent magnet baffle.

[0029] As can be seen from the above technical solutions, compared with the prior art, the present invention provides a self-powered wireless transmission type tensile and compressive magnetostrictive force sensor, which has the following beneficial effects: The present invention can realize the self-powered function of the sensor, get rid of the traditional chemical power supply method; realize the monitoring of the stress and strain of the aircraft rotor; realize the wireless transmission of data; effectively reduce the daily maintenance cost of the aircraft, improve the accuracy of the helicopter load monitoring data, and improve the safety performance during the flight of the helicopter. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to the provided drawings.

[0031] Figure 1 Structural diagram of a self-powered wireless transmission type tensile and compressive magnetostrictive force sensor disclosed by the present invention;

[0032] Figure 2 Schematic application diagram of a self-powered wireless transmission type tensile and compressive magnetostrictive force sensor disclosed in this embodiment;

[0033] Wherein, 1 - energy harvesting module, 2 - lower permanent magnet baffle, 3 - lower permanent magnet, 4 - Hall element, 5 - fixing bracket, 6 - upper permanent magnet, 7 - connecting shaft, 8 - lower piezoelectric ceramic ring, 9 - piezoelectric ceramic ring partition, 10 - upper piezoelectric ceramic ring, 11 - input shaft, 12 - fixing bracket end cover, 13 - pressing ring, 14 - pre-tightening spring, 15 - upper magnetic conductive sheet, 16 - magnetostrictive rod, 17 - lower magnetic conductive sheet, 18 - barrel wall, 19 - data acquisition and wireless radio frequency transmission output module, 20 - chip end cover, 21 - chip barrel wall, 22 - lower end shaft. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0035] In this application, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. The terms "comprising", "including" or any other variant thereof are intended to cover non-exclusive inclusion, such that a process, method, article or device comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or device. Without further limitation, an element defined by the statement "comprising an..." does not exclude the presence of additional identical elements in the process, method, article or device comprising the element.

[0036] Referring to Figure 1 as shown, the present invention discloses a self-powered wireless transmission type tensile and compressive magnetostrictive force sensor, comprising:

[0037] A barrel wall 18, a pressing ring 13 and a lower end shaft 22, and an installation cavity is formed by enclosing between the inner wall of the barrel wall 18, the pressing ring 13 and the lower end shaft 22.

[0038] An input shaft 11 is arranged at the top opening of the barrel wall 18 through the pressing ring 13.

[0039] The input shaft 11 is threadedly connected to the connecting shaft 7, and an upper piezoelectric ceramic ring plate 10 and a lower piezoelectric ceramic ring plate 8 are sequentially arranged between the input shaft 11 and the connecting shaft 7 from top to bottom. Except when a pressure F is applied to the input shaft 11, it is ensured that there is always a piezoelectric ceramic ring plate subjected to a force, and thus energy is supplied. In addition, a piezoelectric ceramic ring plate partition 9 is arranged between the upper piezoelectric ceramic ring plate 10 and the lower piezoelectric ceramic ring plate 8.

[0040] An upper permanent magnet 6 is arranged between the fixed frame end cover 12 and the upper end of the fixed frame 5. The upper permanent magnet 6 is sleeved on the fixed frame 5, and the fixed frame 5 has a circular ring with a cantilever beam structure, which is used to cooperate with the fixed frame end cover 12 to fix the position of the upper permanent magnet 6. A magnetostrictive rod 16 is arranged in the inner cavity of the fixed frame 5. The fixed frame 5 is provided with a slot hole, and a horizontally placed Hall element 4 is attached at the slot hole, and the top end of the Hall element 4 abuts against the magnetostrictive rod 16. Upper and lower magnetic conductive sheets 15 and 17 are respectively placed at the upper and lower ends of the magnetostrictive rod 16, and a pre-tightening spring 14 is arranged between the upper magnetic conductive sheet 15 and the input shaft 11, so that the magnetostrictive rod 16 is pre-loaded with a pre-tightening force.

[0041] The lower end of the fixing bracket 5 is connected to the lower permanent magnet 3, and the position of the lower permanent magnet 3 is fixed by the lower permanent magnet baffle 2 to prevent the position of the lower permanent magnet 3 from changing. In addition, the lower surface of the fixing bracket 5 and the upper surface of the lower permanent magnet 3, and the lower surface of the lower permanent magnet 3 and the upper surface of the lower permanent magnet baffle 2 are adhesively bonded.

[0042] A chip end cover 20 and a chip barrel wall 21 are arranged in the cavity between the lower permanent magnet baffle 2, the barrel wall 18 and the lower end shaft 22. An energy harvesting module 1 and a data acquisition and wireless radio frequency transmitting and outputting module 19 are placed between the chip end cover 20 and the chip barrel wall 21.

[0043] Furthermore, the pressing ring 13 is threadedly connected to the barrel wall 18 to fix the position of the piezoelectric ceramic ring partition 9 and prevent it from moving. At the same time, the piezoelectric ceramic ring partition 9 serves to isolate the upper piezoelectric ceramic ring 10 from the lower piezoelectric ceramic ring 8, ensuring that only one piezoelectric ceramic ring can generate voltage during the working state.

[0044] Furthermore, the input shaft 11 is threadedly connected to the connecting shaft 7. The upper piezoelectric ceramic ring 10 and the lower piezoelectric ceramic ring 8 are sleeved on the connecting shaft 7, and the upper piezoelectric ceramic ring 10 and the lower piezoelectric ceramic ring 8 are separated by the piezoelectric ceramic ring partition 9.

[0045] The distance between the non-contact surfaces of the input shaft 11 and the connecting shaft 7 is equal to the sum of the thicknesses of the upper piezoelectric ceramic ring 10, the lower piezoelectric ceramic ring 8, and the piezoelectric ceramic ring partition 9. The input shaft 11 and the pressing ring 13 are sealed with sealant.

[0046] The input shaft 11 is provided with threads and is threadedly connected to the connecting shaft 7, enabling the force on the input shaft 11 to be transmitted to the connecting shaft 7 and then, through the pre-tightening spring 14 and the upper magnetic conductive sheet 15, to the magnetostrictive rod 16.

[0047] Furthermore, two symmetrical through holes are provided on the piezoelectric ceramic ring partition 9 for the leads of the upper piezoelectric ceramic ring 10 and the lower piezoelectric ceramic ring 8 to access the subsequent circuit through the through holes.

[0048] Furthermore, the inner diameter of the pressing ring 13 matches the outer diameter of the retaining ring of the input shaft 11, and the upper end of the pressing ring 13 is lower than the upper end of the input shaft 11. In addition, sealant is used for sealing between the two.

[0049] Furthermore, the inner diameters of the upper piezoelectric ceramic ring 10, the lower piezoelectric ceramic ring 8, and the piezoelectric ceramic ring partition 9 are equal to the outer diameter at the threaded hole at the upper end of the connecting shaft 7.

[0050] Furthermore, the outer diameter of the inner cavity of the fixing bracket 5 is equal to the inner diameter of the upper permanent magnet 6, the outer diameter of the upper ring of the fixing bracket 5 is equal to the outer diameter of the upper permanent magnet 6, the fixing bracket end cover 12 is connected to the fixing bracket 5, the outer diameter of the lower end of the fixing bracket 5, the outer diameter of the lower permanent magnet 3, and the outer diameter of the upper permanent magnet 6 are equal. The lower permanent magnet 3 is sleeved on the lower permanent magnet baffle 2, the lower diameter of the lower permanent magnet baffle 2 is equal to the inner diameter of the barrel wall 18, and two symmetrical through holes are drilled in the lower permanent magnet baffle 2.

[0051] Specifically, the fixing bracket 5 and the fixing bracket end cover 12 are adhesively bonded. The outer diameter of the upper end of the fixing bracket 5, the outer diameter of the lower end of the fixing bracket end cover 12 are equal to the inner diameter of the upper permanent magnet 6, and the outer diameter of the ring of the cantilever beam structure at the upper end of the fixing bracket 5 is equal to the outer diameter of the upper permanent magnet 6.

[0052] Furthermore, the diameter of the upper magnetic conductive sheet 15, the diameter of the lower magnetic conductive sheet 17, the diameter of the magnetostrictive rod 16, and the inner diameter of the inner cavity of the fixing bracket 5 are equal to the inner diameter at the groove of the lower permanent magnet baffle 2, and the outer diameter of the pre-tightening spring 14 is equal to the inner diameter of the inner cavity of the fixing bracket 5.

[0053] The lower surface of the fixing bracket 5 and the upper surface of the lower permanent magnet 3, and the lower surface of the lower permanent magnet 3 and the upper surface of the lower permanent magnet baffle 2 are adhesively bonded.

[0054] Furthermore, the height of the upper magnetic conductive sheet 15 is lower than the height of the upper permanent magnet 6, and the height of the lower magnetic conductive sheet 17 is higher than the height of the lower permanent magnet 3.

[0055] The upper magnetic conductive sheet 15 is arranged on the top surface of the magnetostrictive rod 6, and the lower magnetic conductive sheet 17 is arranged on the bottom surface of the magnetostrictive rod 6, which is used to guide the magnetic flux of the upper permanent magnet 6 and the lower permanent magnet 3.

[0056] Furthermore, the opposite polarities of the upper permanent magnet 6 and the lower permanent magnet 3 are opposite, which is used to apply a bias magnetic field to the magnetostrictive rod 16.

[0057] Furthermore, the lower permanent magnet baffle 2 is threadedly connected to the inner cavity of the barrel wall 18, the chip end cover 20 and the lower permanent magnet baffle 2 are connected by countersunk head screws, the chip barrel wall 21 and the lower end bearing 22 are connected by countersunk head screws, the chip end cover 20 and the chip barrel wall 21 are threadedly connected, and a through hole is left at the chip barrel wall 21; the lower end bearing 22 is threadedly connected to the inner cavity of the barrel wall 18.

[0058] The lower end shaft 22 is threadedly connected to the inner side of the barrel wall 18, and a retaining ring is provided on the lower end shaft 22, which is closely attached to the bottom of the barrel wall to prevent the interference fit phenomenon from occurring when the lower end shaft 22 is screwed into the inner side of the barrel wall 18, thereby realizing the limitation of the lower end shaft 22 and the lower permanent magnet baffle 2. Furthermore, in cooperation with the piezoelectric ceramic ring plate partition 9, the connecting shaft 7, the magnetostrictive rod 16, the upper magnetic conductive sheet 15 and the lower magnetic conductive sheet 17, a definite position space is reserved for the pre-tightening spring 14, so that the spring pre-tightening force is determined.

[0059] Furthermore, the pre-tightening spring 14 is subjected to a pre-tightening force of magnitude F. At this moment, the magnetostrictive rod 16 and the lower piezoelectric ceramic ring plate 8 are subjected to the force F, ensuring that the magnetostrictive rod 16 is subjected to the force when a pressure or a tensile force is applied to the input shaft 11.

[0060] Furthermore, the energy harvesting module 1 and the data acquisition and radio frequency transmission module 19 are integrally designed, and the height of the integrated chip is the same as the depth of the inner cavity of the chip barrel wall 21. Moreover, a through hole is provided on the side surface of the chip barrel wall 21, and the leads required at the chip are led out from the through hole in advance.

[0061] Furthermore, during the operation of the rotor, one of the upper piezoelectric ceramic ring plate 10 and the lower piezoelectric ceramic ring plate 8 is subjected to a force to generate energy, and thus the self-power supply function can be realized. The energy generated by the piezoelectric ceramic is collected and stored by the energy harvesting module 1. The voltage output terminal lead of the energy harvesting module 1 is connected to the input terminal leads of the Hall element 4 and the data acquisition and radio frequency transmission output module 19. The energy harvesting module 1 is used to supply power to the Hall element 4 and the data acquisition and radio frequency transmission output module 19. The voltage signal at the output terminal of the Hall element 4 is converted into a digital signal through an ADC and connected to the input terminal of the data acquisition and radio frequency transmission output module 19 to realize the monitoring of the voltage signal of the Hall element 4. In addition, during the flight of the aircraft, if the force on the rotor remains unchanged, the electric energy stored in the energy harvesting module 1 at this time can supply the Hall element 4 and the data acquisition and radio frequency transmission output module 19 to maintain a certain working time, ensuring the uninterrupted monitoring of the rotor load.

[0062] Specifically, the lower end shaft 22, the input shaft 11 and the connecting shaft 7 are limited in position, and the pre-tightening spring 14 between the connecting shaft 7 and the upper magnetic conductive sheet 15 is also fixed accordingly and is subjected to a certain pre-tightening force F. The force applied to the input shaft 11 in the initial state is 0. The connecting shaft 7, the input shaft 11 and the lower piezoelectric ceramic ring 8 are subjected to an upward force F. During the working process, when the screw propeller is stressed and the input shaft 11 applies a force, when the applied pressure F0 satisfies 0 ≤ F0 < F, the lower piezoelectric ceramic ring 8 is stressed to generate energy, and the upper piezoelectric ceramic ring 10 is not stressed. When the pressure applied to the input shaft 11 is F, the upper and lower piezoelectric ceramic rings are not stressed. When the pressure applied to the input shaft 11 is greater than F, the lower piezoelectric ceramic ring 8 is not stressed, and the upper piezoelectric ceramic ring 10 is stressed to generate electric energy; when the input shaft 11 applies a tensile force, the upper piezoelectric ceramic ring 10 is not stressed, and the lower piezoelectric ceramic ring 8 is stressed to generate energy. This ensures that when the input shaft 11 is subjected to a force greater than or less than F, there is always a piezoelectric ceramic ring that can be stressed to generate vibration and a certain amount of charge, realizing the self-power supply function. In the state where the input shaft 11 is subjected to the pressure F, the piezoelectric ceramic ring is not stressed and does not generate energy at this time. However, since the energy harvesting module 1 stores electric energy, the rotor load monitoring can still be realized. In addition, the state where the input shaft 11 is subjected to the pressure F lasts for a very short time and has no impact on the entire energy harvesting. The energy harvesting module 1 collects the generated charges to supply power to the Hall element 4 and the data acquisition and radio frequency transmission output module 19; the magnetostrictive sensor has the magnetostrictive rod 16 as the main core structure, and high-permeability magnetic conductive sheets are placed above and below the giant magnetostrictive rod 16, which can realize the guidance of magnetic flux and make the magnetic flux density distribution in the magnetostrictive rod 16 uniform.

[0063] Specifically, a slot hole is opened on the fixing bracket 5, and a horizontally placed Hall element 4 is closely attached to the slot hole. The top end of the Hall element 4 abuts against the magnetostrictive rod 16. The voltage generated by the piezoelectric ceramic and collected supplies power to the Hall element 4 through the energy harvesting module 1. The Hall element 4 is placed in the bias magnetic field generated by the upper permanent magnet 6 and the lower permanent magnet 3. When the magnetostrictive rod 16 is subjected to a dynamic force under the action of the input shaft 11, the magnetic permeability of the magnetostrictive rod 16 changes. Since the magnetostrictive rod 16 is located in the magnetic field generated by the permanent magnet, the change in magnetic permeability affects the change in magnetic flux, and further leads to the change in the voltage of the Hall element 4. This voltage is converted into a digital signal by the signal conditioning circuit and collected by the data acquisition circuit. The magnitude of the bias magnetic field applied to the entire structure by the upper permanent magnet 6 and the lower permanent magnet 3 can also be detected through the Hall element 4; by collecting the voltage signal output by the Hall element 4, the magnitude of the magnetic induction intensity on the magnetostrictive rod 16 can be measured, and the magnitude of the force applied to the input shaft 11 can be detected.

[0064] See Figure 2 As shown, the self-powered wireless transmission type tensile and compressive magnetostrictive force sensor consists of an energy harvester, a magnetostrictive load sensor, wireless intelligent transmission, and an embedded load monitoring system. During the process of applying force to the piezoelectric stack on the input shaft 11, the piezoelectric stack generates electrical energy, which is stored in the battery through a capacitor, after processes such as AC / DC conversion, voltage regulator, and voltage amplifier, thus forming the energy harvester. The energy harvester powers the magnetostrictive load sensor, wireless intelligent transmission, and embedded load monitoring system. The output end of the Hall element 4 inside the magnetostrictive load sensor is connected to the embedded load monitoring system through voltage stabilization filtering, A / D conversion, etc. The system analyzes the detected signal and transmits it wirelessly to the host interface to achieve the monitoring of force. Through the above, the self-powered function of the sensor is realized, and the magnitude of the rotor load is monitored in real time.

[0065] In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described according to functions in the above description. Whether these functions are executed in a hardware or software manner depends on the specific application and design constraints of the technical solution. A person skilled in the art can use different methods for each specific application to implement the described functions, but such implementation should not be considered to exceed the scope of the present invention.

[0066] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A self-powered wireless transmission type tensile and compressive magnetostrictive force sensor, characterized in that Comprising: A barrel wall (18), a pressing ring (13) and a lower end shaft (22), an installation cavity is formed by enclosing between the inner wall of the barrel wall (18), the pressing ring (13) and the lower end shaft (22); An input shaft (11) passes through the pressing ring (13) and is arranged at the top opening of the barrel wall (18); An upper piezoelectric ceramic ring plate (10) and a lower piezoelectric ceramic ring plate (8) are sequentially arranged from top to bottom between the input shaft (11) and the connecting shaft (7), and a piezoelectric ceramic ring plate partition (9) is arranged between the upper piezoelectric ceramic ring plate (10) and the lower piezoelectric ceramic ring plate (8); An upper permanent magnet (6) is arranged between the fixed frame end cover (12) and the upper end of the fixed frame (5). A magnetostrictive rod (16) is arranged in the inner cavity of the fixed frame (5). A slot hole is formed in the fixed frame (5). A Hall element (4) is horizontally attached tightly at the slot hole, and the top end of the Hall element (4) abuts against the magnetostrictive rod (16). Upper and lower magnetic conductive sheets (15) and (17) are respectively arranged at the upper and lower ends of the magnetostrictive rod (16); A pre-tightening spring (14) is installed between the upper magnetic conductive sheet (15) and the connecting shaft (7); The lower end of the fixed frame (5) is connected to a lower permanent magnet (3), and the position of the lower permanent magnet (3) is fixed by a lower permanent magnet baffle (2); A chip end cover (20) and a chip barrel wall (21) are arranged in the space enclosed by the lower permanent magnet baffle (2), the barrel wall (18) and the lower end shaft (22). An energy harvesting module (1) and a data acquisition and wireless radio frequency transmitting and outputting module (19) are arranged between the chip end cover (20) and the chip barrel wall (21); The pressing ring (13) and the barrel wall (18) are connected by threads to fix the position of the piezoelectric ceramic ring plate partition (9); The input shaft (11) and the connecting shaft (7) are connected by threads. The upper piezoelectric ceramic ring plate (10) and the lower piezoelectric ceramic ring plate (8) are sleeved on the connecting shaft (7), and the upper piezoelectric ceramic ring plate (10) and the lower piezoelectric ceramic ring plate (8) are separated by the piezoelectric ceramic ring plate partition (9); In addition, two symmetrical through holes are provided on the piezoelectric ceramic ring plate partition (9) for the leads of the upper piezoelectric ceramic ring plate (10) and the lower piezoelectric ceramic ring plate (8) to access the subsequent circuit through the through holes; The inner diameters of the upper piezoelectric ceramic ring plate (10), the lower piezoelectric ceramic ring plate (8), the piezoelectric ceramic ring plate partition (9) are equal to the outer diameter of the threaded hole of the connecting shaft (7); The outer diameter of the inner cavity of the fixed frame (5) is equal to the inner diameter of the upper permanent magnet (6). The outer diameter of the upper end ring of the fixed frame (5) is equal to the outer diameter of the upper permanent magnet (6). The fixed frame end cover (12) is connected to the fixed frame (5). The outer diameter of the lower end of the fixed frame (5), the outer diameter of the lower permanent magnet (3), and the outer diameter of the upper permanent magnet (6) are equal. And the lower permanent magnet (3) is sleeved on the lower permanent magnet baffle (2). The lower end diameter of the lower permanent magnet baffle (2) is equal to the inner diameter of the barrel wall (18), and two symmetrical through holes are provided on the lower permanent magnet baffle (2); The diameters of the upper magnetic conductive sheet (15), the lower magnetic conductive sheet (17), the magnetostrictive rod (16), the outer diameter of the pre-tightening spring (14) are equal to the inner diameter of the groove of the lower permanent magnet baffle (2).

2. The self-powered wireless transmission type tensile and compressive magnetostrictive force sensor according to claim 1, characterized in that The inner diameter of the pressing ring (13) matches the outer diameter of the retaining ring of the input shaft (11), and the upper end of the pressing ring (13) is lower than the upper end of the input shaft (11). In addition, sealant is used for sealing between the two.

3. The self-powered wireless transmission type tensile and compressive magnetostrictive force sensor according to claim 1, characterized in that The lower surface of the fixing frame (5) is adhesively bonded to the upper surface of the lower permanent magnet (3), and the lower surface of the lower permanent magnet (3) is adhesively bonded to the upper surface of the lower permanent magnet baffle (2).

4. The self-powered wireless transmission type tensile and compressive magnetostrictive force sensor according to claim 1, characterized in that The height of the upper magnetic conductive sheet (15) is lower than the height of the upper permanent magnet (6), and the height of the lower magnetic conductive sheet (17) is higher than the height of the lower permanent magnet (3); The upper magnetic conductive sheet (15) is arranged on the top surface of the magnetostrictive rod (16), and the lower magnetic conductive sheet (17) is arranged on the bottom surface of the magnetostrictive rod (16) to guide the magnetic flux of the upper permanent magnet (6) and the lower permanent magnet (3).

5. The self-powered wireless transmission type tensile and compressive magnetostrictive force sensor according to claim 1, characterized in that The opposite surfaces of the upper permanent magnet (6) and the lower permanent magnet (3) have opposite polarities to apply a bias magnetic field to the magnetostrictive rod (16).

6. The self-powered wireless transmission type tensile and compressive magnetostrictive force sensor according to claim 1, characterized in that The chip end cover (20) is connected to the lower permanent magnet baffle (2) by countersunk head screws, the chip barrel wall (21) is connected to the lower end shaft (22) by countersunk head screws, and the chip end cover (20) is threadedly connected to the chip barrel wall (21), and a through hole is left at the chip barrel wall (21).

7. The self-powered wireless transmission type tensile and compressive magnetostrictive force sensor according to claim 1, characterized in that The lower permanent magnet baffle (2) is threadedly connected to the inner side of the barrel wall (18), the lower end shaft (22) is threadedly connected to the inner side of the barrel wall (18), and a retaining ring is provided on the lower end shaft (22), which is closely attached to the bottom of the barrel wall to prevent the lower end shaft (22) from having an interference fit when screwing into the inner side of the barrel wall (18), thereby realizing the limitation of the lower end shaft (22) and the lower permanent magnet baffle (2).

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