A frequency adaptive vibration energy harvester for wireless smart sensing

Abstract

The frequency self-adaptive vibration energy collector for wireless intelligent sensing comprises a vibration frequency conversion assembly, a main vibrator, a power conversion assembly, a vibration frequency sensing assembly and an energy collection assembly.

Description

Technical Field

[0001] This article relates to a power supply technology, and more particularly to a frequency-adaptive vibration energy harvester for wireless intelligent sensing. Background Technology

[0002] Existing wireless sensors used for monitoring industrial equipment are mostly battery-powered, with a battery replacement cycle of 2-3 years. Due to power supply issues, the sampling interval of wireless sensors for industrial equipment is mostly around 2 hours. Therefore, the power supply problem of wireless sensors has become one of the bottlenecks in improving the effectiveness of predictive maintenance at present.

[0003] To overcome this bottleneck, a vibration energy harvester is proposed in the relevant technical solutions. This harvester incorporates oscillators that convert the vibrational energy of the oscillators into electrical energy to continuously power the wireless sensor. Since the oscillators need to resonate to stably provide greater vibrational energy, and the excitation frequency driving the oscillators changes with the operating environment, the harvester uses multiple oscillators with different intrinsic frequencies (e.g., four oscillators). When the excitation frequency approaches the intrinsic frequency of any one of the oscillators, that oscillator can resonate, thereby generating more stable electrical energy output.

[0004] Using multiple oscillators can achieve wide-band coverage of the resonant frequency, ensuring that at least one oscillator will always resonate. However, mass is the primary resource for vibration energy harvesting, and the upper limit of vibration energy harvesting power is directly proportional to the mass of the resonating oscillator. Limited by the size of the vibration energy harvester, the total mass of multiple oscillators has an upper limit. Setting multiple oscillators within the limited internal space of the vibration energy harvester is equivalent to dividing the oscillator mass resource into multiple parts, sacrificing the maximum output power achieved when only one oscillator resonates, in exchange for a more stable low-power output at different excitation frequencies.

[0005] Therefore, the vibration energy harvester in the relevant technical solutions cannot simultaneously meet the requirements of wide frequency coverage of the resonant frequency and large output power. Summary of the Invention

[0006] This application provides a vibration energy harvester, which includes:

[0007] Vibration frequency converter components include:

[0008] The base is provided with a first pivot; and,

[0009] The first elastic element includes a cylinder sleeved on the first rotating shaft and capable of rotating around the first rotating shaft, and a first elastic sheet extending radially outward from the cylinder. The thickness of the first elastic sheet is uneven in the circumferential direction of the cylinder.

[0010] The main oscillator is rotatably connected to the first elastic sheet and is configured to not rotate relative to the base.

[0011] A power conversion component is used to convert the vibration transmitted to the power conversion component into torque that drives the first elastic element to rotate;

[0012] A vibration frequency sensing component is used to detect the excitation frequency of the vibration applied by the vibration source, and to prevent the first elastic element from rotating when it rotates to a position where the eigenfrequency of the main oscillator reaches the excitation frequency; and,

[0013] An energy harvesting component is used to convert the vibrational energy of the main oscillator into electrical energy and then output it.

[0014] In one illustrative embodiment, the main oscillator is provided with a mounting cavity and a first straight hole extending from the mounting cavity to the bottom end of the main oscillator, and the first rotating shaft extends into the mounting cavity along the first straight hole;

[0015] The first elastic element further includes a second elastic sheet of uneven thickness, and the first elastic sheet and the second elastic sheet extend radially outward from opposite ends of the cylinder, respectively;

[0016] The vibration frequency conversion assembly also includes two bearing sleeves respectively disposed at the top and bottom of the mounting cavity, and thrust bearings respectively located in the two bearing sleeves;

[0017] The first elastic sheet and the second elastic sheet are disposed between the two thrust bearings, and the opposite ends of the first elastic sheet and the second elastic sheet abut against the two thrust bearings respectively.

[0018] In one illustrative embodiment, the first elastic sheet is constructed as an annular shape, and a first groove distributed in a fan-shaped annular pattern is provided at one end of the first elastic sheet facing the second elastic sheet, with the depth of the first groove gradually changing upwards from the circumference of the first elastic sheet; and / or,

[0019] The second elastic sheet is constructed as a ring, and a second groove distributed in a fan-shaped ring is provided at one end of the second elastic sheet facing the first elastic sheet. The depth of the second groove gradually changes from circumferential to circumferential on the second elastic sheet.

[0020] In one illustrative embodiment, the central angle of the first groove is 90°, and there are two first grooves, which are symmetrically arranged on both sides of the first elastic sheet.

[0021] There are two second grooves, which are symmetrically arranged on both sides of the second elastic sheet;

[0022] The first groove and the second groove are offset in the axial direction of the first elastic sheet, and the first groove and the second groove have the same shape.

[0023] In one illustrative embodiment, the base includes a base body and a support column extending vertically upward from the base body. The outer diameter of the support column is larger than the inner diameter of the cylinder. The first rotating shaft is disposed at the top of the support column and is coaxial with the support column.

[0024] The main oscillator includes:

[0025] A lower counterweight, wherein the top center of the lower counterweight is recessed downward to form the mounting cavity, and the first straight hole extends from the mounting cavity to the bottom end of the lower counterweight; and,

[0026] The upper counterweight covers the top of the lower counterweight and is detachably connected to the upper counterweight.

[0027] In one illustrative embodiment, both the lower counterweight and the upper counterweight are constructed as vertical cylinders coaxial with the first rotating shaft.

[0028] In one illustrative embodiment, the energy harvesting assembly includes a coil disposed on the base and a magnet disposed on the main oscillator;

[0029] One side of the coil is close to the magnet, and the other side is far from the magnet, so that the magnetic field strength of the coil is different on opposite sides.

[0030] In one illustrative embodiment, two magnets are provided, spaced apart, with opposite magnetic poles at their ends closest to each other;

[0031] Two coils are provided, with one side of each coil connected to the base and the other side of each coil disposed between the two magnets. The two coils are connected in series so that the induced electromotive forces generated by the two coils are superimposed in the same direction.

[0032] In one illustrative embodiment, the energy harvesting assembly includes a piezoelectric ceramic sandwiched between the main oscillator and the base; and / or,

[0033] The power conversion component includes an ultrasonic motor powered by the energy harvesting component.

[0034] In one illustrative embodiment, a transmission component is also included;

[0035] The transmission component is connected to the first elastic element and the power conversion component, and is used to boost the torque output by the power conversion component and then transmit it to the first elastic element.

[0036] In one illustrative embodiment, the transmission assembly includes:

[0037] An internal gear ring is connected to the top of the main oscillator and is coaxially arranged with the first rotating shaft;

[0038] The central gear is disposed within the internal gear ring and is coaxially arranged with the internal gear ring;

[0039] Multiple planetary gears are disposed between the internal gear ring and the central gear, and mesh with the internal gear ring and the central gear;

[0040] A planetary carrier is disposed on the side of the planetary gears near the main oscillator and is rotatably connected to each of the planetary gears;

[0041] The second rotating shaft is coaxially arranged with the first rotating shaft, and its two ends are respectively connected to the planetary carrier and the first elastic element;

[0042] The third rotating shaft is coaxially arranged with the central gear, with one end connected to the central gear and the other end connected to the power conversion component.

[0043] In one illustrative embodiment, the transmission assembly further includes a cover plate that covers one end of the internal gear ring facing away from the main oscillator;

[0044] The power conversion component includes:

[0045] The outer casing is connected to the base;

[0046] A rotating component includes a turntable rotatably connected to the housing, the turntable being rotatable about the axis of the third rotating shaft;

[0047] A friction plate abuts against the end of the turntable near the cover plate; and

[0048] The second elastic element, with its two ends connected to the friction plate and the cover plate respectively, is configured to undergo both elastic deformation and torsional elastic deformation in the axial direction of the third rotating shaft.

[0049] The cover plate is provided with a first through hole, the friction plate is provided with a second through hole, and the third rotating shaft passes through the first through hole and the second through hole and is connected to the turntable.

[0050] In one illustrative embodiment, the second elastic member includes:

[0051] A first ring is connected to the cover plate, and the third rotating shaft passes through the first ring;

[0052] Multiple spring bars are evenly distributed in the circumferential direction of the third rotating shaft;

[0053] In this embodiment, multiple spring bars extend spirally from the first annulus to the friction plate, and the spiral directions are the same.

[0054] In one illustrative embodiment, the rotating component further includes a positioning plate disposed on the side of the turntable facing away from the friction plate and a connecting portion connecting the positioning plate and the turntable, wherein the positioning plate is coaxially disposed with the turntable;

[0055] The card slot is provided on the side of the card slot facing away from the turntable, and the card slot is eccentrically set on the card slot.

[0056] The vibration frequency sensing component includes:

[0057] The oscillator ring includes an annular base connected to the outer shell and a plurality of secondary oscillators elastically connected to the annular base;

[0058] Top plate, connected to the annular base; and,

[0059] The blocking component includes a column connected at one end to the top plate and a plurality of blocking plates that are elastically connected to the column.

[0060] The plurality of blocking plates are arranged in a ring above the movement trajectory of the card slot. A plurality of secondary vibrators extend from the ring base to the side of the blocking plates facing away from the card slot plate. The blocking plates are configured such that they can only be struck by the secondary vibrator to the extent that they can be deflected into the card slot when the secondary vibrator resonates. The resonant frequencies of the multiple secondary vibrators are different from each other. When the card slot rotates to the position directly below any blocking plate, the first elastic element rotates to the position where the resonant frequency of the main vibrator is equal to the resonant frequency of the secondary vibrator corresponding to the blocking plate.

[0061] In one illustrative embodiment, the secondary oscillator includes a first oscillator elastically connected to the annular base and a second oscillator elastically connected to the first oscillator;

[0062] The first oscillator and the second oscillator have the same eigenfrequency, the mass of the first oscillator is greater than the mass of the second oscillator, and the second oscillator strikes the blocking plate when resonance occurs.

[0063] In one illustrative embodiment, the blocking sheet has a buffer membrane disposed on the surface facing the sub-oscillator.

[0064] In one illustrative embodiment, the electromagnetic damping of the main oscillator is 100 N·s / m.

[0065] In the technical solution of this application, after the vibration energy harvester is placed on the vibration source, the vibration energy harvester vibrates along with the vibration source. The power conversion component can convert a portion of the vibration into torque to drive the first elastic element to rotate. As the first elastic element rotates, the eigenfrequency of the main oscillator changes. The vibration frequency sensing component can detect the excitation frequency of the vibration applied by the vibration source and prevent the first elastic element from rotating when the eigenfrequency of the main oscillator reaches the excitation frequency, thereby locking the eigenfrequency of the main oscillator. Since the eigenfrequency of the main oscillator is the same as the excitation frequency, the main oscillator resonates. The energy harvesting component converts the vibration energy of the main oscillator during resonance into electrical energy, which can supply stable power to other electrical devices. The vibration energy harvester can adjust the eigenfrequency of the main oscillator by adjusting the rotation position of the first elastic element, so that the eigenfrequency of the main oscillator is consistent with the excitation frequency. The eigenfrequency of the main oscillator can adapt to various different excitation frequencies, satisfying the wide frequency coverage of the resonance frequency. Furthermore, since the energy harvesting component only needs to harvest the vibration energy of one main oscillator, the mass of the main oscillator can be set as large as possible, thereby maximizing the output power of the energy harvesting component.

[0066] Other features and advantages of this application will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the application. Other advantages of this application can be realized and obtained by means of the solutions described in the description and the accompanying drawings. Attached Figure Description

[0067] The accompanying drawings are used to provide an understanding of the technical solutions of this application and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions of this application.

[0068] Figure 1 This is a full cross-sectional schematic diagram of a vibration energy harvester according to an embodiment of this application;

[0069] Figure 2 This is a disassembly diagram of a vibration energy harvester according to an embodiment of this application;

[0070] Figure 3 This is a full cross-sectional schematic diagram of the vibration frequency conversion component and the energy harvesting component in the embodiments of this application;

[0071] Figure 4 This is a disassembly diagram of the vibration frequency converter component in the embodiments of this application;

[0072] Figure 5 This is a three-dimensional schematic diagram of the first elastic element in an embodiment of this application;

[0073] Figure 6This is a three-dimensional schematic diagram of the lower counterweight block in an embodiment of this application;

[0074] Figure 7 This is a three-dimensional schematic diagram of the lower counterweight block from another perspective in an embodiment of this application;

[0075] Figure 8 This is a disassembled schematic diagram of the energy harvesting component in an embodiment of this application;

[0076] Figure 9 This is a three-dimensional schematic diagram of the base and coil in the embodiments of this application;

[0077] Figure 10 This is a perspective view of the transmission component in the embodiments of this application;

[0078] Figure 11 This is a full cross-sectional schematic diagram of the transmission component in the embodiments of this application;

[0079] Figure 12 This is a three-dimensional schematic diagram of the planetary gear, planet carrier, and second shaft in the embodiments of this application;

[0080] Figure 13 This is a three-dimensional schematic diagram of the first elastic element and the second rotating shaft in the embodiments of this application;

[0081] Figure 14 This is a full cross-sectional schematic diagram of the power conversion component in the embodiments of this application;

[0082] Figure 15 This is a disassembled schematic diagram of the power conversion component in the embodiments of this application;

[0083] Figure 16 This is a schematic diagram of the second elastic element and friction plate in an embodiment of this application;

[0084] Figure 17 This is a schematic diagram of the friction plate in an embodiment of this application;

[0085] Figure 18 This is a three-dimensional schematic diagram of the disassembled vibration frequency sensing component in an embodiment of this application;

[0086] Figure 19 This is a full cross-sectional schematic diagram of the vibration frequency sensing component in the embodiments of this application;

[0087] Figure 20 This is a three-dimensional schematic diagram of the oscillator coil in the embodiments of this application;

[0088] Figure 21 This is a full cross-sectional schematic diagram of the oscillator ring in the embodiments of this application;

[0089] Figure 22 This is a perspective view of the blocking element in the embodiments of this application;

[0090] Figure 23 This is a schematic diagram showing the correspondence between the rotation angle of the first elastic element and the eigenfrequency of the main oscillator in an embodiment of this application;

[0091] Figure 24 This is a schematic diagram of the first type of x-θ phase diagram in the embodiments of this application;

[0092] Figure 25 This is a schematic diagram of the second type of x-θ phase diagram in the embodiments of this application;

[0093] Figure 26 This is a schematic diagram of the third x-θ phase diagram in the embodiments of this application;

[0094] Figure 27 This is a schematic diagram of an N-θ phase diagram in an embodiment of this application;

[0095] Figure 28 This is a waveform diagram of the normal pressure changing over time in the embodiments of this application;

[0096] Figure 29 This is a time-domain diagram of an excitation acceleration signal in one of the embodiments of this application;

[0097] Figure 30 This is a frequency domain diagram of an excitation acceleration signal in an embodiment of this application;

[0098] Figure 31 The simulation results of the main oscillator of the vibration energy harvester in the embodiment of this application being in a resonant state are shown in the figure.

[0099] Figure 32 The simulation results are shown in the embodiment of the vibration energy harvester in this application when the eigenfrequency of the main oscillator is offset by 15Hz from the excitation frequency.

[0100] Figure 33 Simulation results of a vibration energy harvesting device where the eigenfrequency of the main oscillator cannot be adjusted;

[0101] Figure 34 This is a three-dimensional schematic diagram of the rotating component in the embodiments of this application. Detailed Implementation

[0102] This application describes several embodiments, but these descriptions are exemplary and not restrictive, and it will be apparent to those skilled in the art that many more embodiments and implementations are possible within the scope of the embodiments described herein. Although many possible combinations of features are shown in the drawings and discussed in the detailed description, many other combinations of the disclosed features are also possible. Unless specifically limited, any feature or element of any embodiment may be used in combination with, or may replace, any feature or element of any other embodiment.

[0103] This application includes and contemplates combinations of features and elements known to those skilled in the art. The embodiments, features, and elements disclosed in this application can also be combined with any conventional features or elements to form unique inventive solutions. Any feature or element of any embodiment can also be combined with features or elements from other inventive solutions to form another unique inventive solution. Therefore, it should be understood that any feature shown and / or discussed in this application can be implemented individually or in any suitable combination. Therefore, the embodiments are not limited except by the limitations imposed by the appended claims and their equivalents. Furthermore, various modifications and changes can be made within the scope of the appended claims.

[0104] Furthermore, in describing representative embodiments, the specification may have presented methods and / or processes as a specific sequence of steps. However, the method or process should not be limited to the specific order of steps described herein, to the extent that it does not depend on such a specific order. As will be understood by those skilled in the art, other sequences of steps are also possible. Therefore, the specific order of steps set forth in the specification should not be construed as a limitation of the claims. Moreover, the claims concerning the method and / or process should not be limited to the steps performed in the written order, and those skilled in the art will readily understand that these orders can be varied and still remain within the spirit and scope of the embodiments of this application.

[0105] like Figure 1 , 2 As shown, Figure 1 , 2 A vibration energy harvester 100 is shown in an embodiment of this application. The vibration energy harvester 100 includes a vibration frequency conversion component 101, a power conversion component 103, a vibration frequency sensing component 104, and an energy harvesting component 102.

[0106] like Figure 3 , 4As shown, the vibration frequency conversion assembly 101 includes a base 1, a first elastic element 9, and a main oscillator 600. The base 1 can be constructed as a thin-shell structure. The base 1 is fixed to a vibration source (not shown in the figure), which can be a mechanical device. The vibration source can emit vibration waves, which are transmitted to the vibration energy harvester 100 through the base 1. A first rotating shaft 10 is provided on the base 1. The first rotating shaft 10 is vertically arranged. The bottom end of the first rotating shaft 10 is connected to the base 1.

[0107] like Figure 5 As shown, the first elastic element 9 includes a cylindrical body 91 and a first elastic plate 92. The cylindrical body 91 can be constructed as a cylinder. The cylindrical body 91 is sleeved on the first rotating shaft 10. There is a clearance fit between the cylindrical body 91 and the first rotating shaft 10. The cylindrical body 91 can rotate freely around the first rotating shaft 10. The first elastic plate 92 extends radially outward from the outer circumferential surface of the cylindrical body 91. The first elastic plate 92 is constructed as a plate. The first elastic plate 92 is perpendicular to the first rotating shaft 10. The thickness of the first elastic plate 92 is uneven in the circumferential direction of the cylindrical body 91. For example, the thickness of the first elastic plate 92 gradually decreases in one circumferential direction of the cylindrical body 91. The first elastic element 9 can be made of spring steel, and the first elastic plate 92 is elastic and can undergo elastic deformation.

[0108] The main oscillator 600 is rotatably connected to the first elastic plate 92, which can rotate relative to the main oscillator 600 around the first rotating shaft 10. The first elastic plate 92 supports the main oscillator 600. The main oscillator 600 is configured to not rotate relative to the base 1. A corresponding limiting structure can be provided between the main oscillator 600 and the base 1 to limit the rotation of the main oscillator 600. For example, a limiting groove can be provided on the bottom surface of the main oscillator 600, and a limiting protrusion extending into the limiting groove can be provided on the base 1. A large gap can be provided between the limiting protrusion and the limiting groove to avoid the limiting part hindering the vibration of the main oscillator 600. The mass of the main oscillator 600 can be set as large as possible. The mass of the main oscillator 600 can account for more than 70% of the total mass of the vibration energy harvester 100, and the volume of the main oscillator 600 can account for more than 70% of the total volume of the vibration energy harvester 100. The main oscillator 600 can be made of a high-density material, such as iron, lead, or other metal materials.

[0109] The power conversion component 103 is connected to the first elastic element 9 via a transmission mechanism or directly to the first elastic element 9. The power conversion component 103 converts external vibrations into torque to drive the first elastic element 9 to rotate in a preset direction. From a top-view perspective, this preset direction can be clockwise or counterclockwise. Because the thickness of the first elastic sheet 92 is uneven along the circumference of the cylinder 91, the elastic coefficient of the first elastic element 9 changes when it rotates relative to the main oscillator 600, thereby altering the eigenfrequency of the main oscillator 600. There is a known correspondence between the rotational position of the first elastic element 9 and the eigenfrequency of the main oscillator 600; the rotational position of the first elastic element 9 can be represented by the angle of rotation.

[0110] The vibration frequency sensing component 104 can detect the excitation frequency of the vibration applied by the vibration source to the vibration energy harvester 100, and the excitation frequency is reached when the first elastic element 9 rotates to the intrinsic frequency of the main oscillator 600. The vibration frequency sensing component 104 can either cut off the torque transmission between the power conversion component 103 and the first elastic element 9, or it can directly jam the first elastic element 9 or the rotating part of the power conversion component 103, thereby preventing the rotation of the first elastic element 9.

[0111] The energy harvesting component 102 is used to convert the vibration energy of the main oscillator 600 into electrical energy. The energy harvesting component 102 may utilize magnetoelectric induction or the piezoelectric effect to convert vibration energy into electrical energy. The energy harvesting component 102 can output electrical energy, allowing the vibration energy harvester 100 to serve as a power source for other electrical devices. For example, the vibration energy harvester 100 can serve as a power source for a wireless sensor, providing power to the wireless sensor.

[0112] In this way, after the vibration energy harvester 100 is placed on the vibration source, the vibration energy harvester 100 vibrates along with the vibration source. The power conversion component 103 can convert a portion of the vibration into torque to drive the first elastic element 9 to rotate. As the first elastic element 9 rotates, the natural frequency of the main oscillator 600 changes. The vibration frequency sensing component 104 can detect the excitation frequency of the vibration applied by the vibration source, and prevent the first elastic element 9 from rotating when the natural frequency of the main oscillator 600 reaches the excitation frequency, thereby locking the natural frequency of the main oscillator 600. Since the natural frequency of the main oscillator 600 is the same as the excitation frequency, the main oscillator 600 resonates. The energy harvesting component 102 converts the vibration energy of the main oscillator 600 during resonance into electrical energy, which can supply stable power to other electrical devices. The vibration energy harvester 100 can adjust the intrinsic frequency of the main oscillator 600 by adjusting the rotational position of the first elastic element 9, ensuring that the intrinsic frequency of the main oscillator 600 is consistent with the excitation frequency. The intrinsic frequency of the main oscillator 600 can adapt to various different excitation frequencies, satisfying the wide frequency coverage of the resonance frequency. Furthermore, since the energy harvesting component 102 only needs to harvest the vibration energy of one main oscillator 600, the mass of the main oscillator 600 can be set as large as possible, maximizing the output power of the energy harvesting component 102.

[0113] In one illustrative embodiment, such as... Figure 1 As shown, the main oscillator 600 has a mounting cavity 61 and a first straight hole 62. The mounting cavity 61 can be a vertical cylindrical chamber. The main oscillator 600 can be configured as a vertical cylinder. The mounting cavity 61 is coaxially arranged with the main oscillator 600. The first straight hole 62 has a circular cross-section and extends vertically. The inner diameter of the first straight hole 62 is smaller than the inner diameter of the mounting cavity 61. The first straight hole 62 extends from the middle of the bottom end of the mounting cavity 61 to the middle of the bottom end of the main oscillator 600. The first rotating shaft 10 extends along the first straight hole 62, and one end of the first rotating shaft 10 extends into the mounting cavity 61 along the first straight hole 62. The diameter of the first rotating shaft 10 is smaller than the inner diameter of the first straight hole 62, and there is an annular gap between the first rotating shaft 10 and the first straight hole 62. The mounting cavity 61 and the first straight hole 62 are both coaxially arranged with the first rotating shaft 10.

[0114] like Figure 3 , 5 As shown, the first elastic element 9 also includes a second elastic sheet 93. The thickness of the second elastic sheet 93 is uneven. The first elastic sheet 92 and the second elastic sheet 93 extend radially outward from opposite ends of the cylinder 91, respectively. In this embodiment, the first elastic sheet 92 extends radially outward from the top end of the cylinder 91, and the second elastic sheet 93 extends radially outward from the bottom end of the cylinder 91. Both the first elastic sheet 92 and the second elastic sheet 93 are horizontally arranged. The first elastic element 9 is located within the mounting cavity 61.

[0115] The vibration frequency converter assembly 101 also includes two bearing sleeves 7 and two thrust bearings 8. The bearing sleeves 7 are cylindrical in shape and have through holes at their bottom. The two bearing sleeves 7 are respectively disposed at the top and bottom of the mounting cavity 61, spaced apart. The bearing sleeves 7 are coaxially arranged with the mounting cavity 61, and the bearing sleeves 7 and the mounting cavity 61 can have an interference fit. The openings of the two bearing sleeves 7 face each other. The two thrust bearings 8 are respectively disposed within the two bearing sleeves 7, and both are coaxially arranged with the mounting cavity 61. A first elastic element 92 and a second elastic element 93 are both disposed between the two thrust bearings 8. The end of the first elastic element 92 facing away from the second elastic element 93 abuts against the thrust washer of one thrust bearing 8, and the end of the second elastic element 93 facing away from the first elastic element 92 abuts against the thrust washer of the other thrust bearing 8.

[0116] In this way, the first elastic plate 92 and the second elastic plate 93 are sandwiched between the two thrust bearings 8. The first elastic plate 92 and the second elastic plate 93 together support the main oscillator 600. The first elastic element 9 is rotatably connected to the main oscillator 600 through the two thrust bearings 8, so that the first elastic element 9 can rotate relative to the main oscillator 600.

[0117] In one illustrative embodiment, the first elastic sheet 92 is constructed as an annular shape. A first groove 921, arranged in a fan-shaped annular pattern, is provided at one end of the first elastic sheet 92 facing the second elastic sheet 93. The depth of the first groove 921 gradually increases circumferentially from the first elastic sheet 92.

[0118] The second elastic sheet 93 is annular in shape, and a second groove 931 arranged in a fan-shaped annular pattern is provided at the end of the second elastic sheet 93 facing the first elastic sheet 92. The depth of the second groove 931 gradually changes upward from the second elastic sheet 93.

[0119] The thickness of the first elastic sheet 92 is controlled by setting a first groove 921 on the first elastic sheet 92, and the thickness of the second elastic sheet 93 is controlled by setting a second groove 931 on the second elastic sheet 93. The depths of the first groove 921 and the second groove 931 gradually change in the circumferential direction, so that the eigenfrequency of the main oscillator 600 can change continuously when the first elastic element 9 rotates.

[0120] In one illustrative embodiment, the central angle of the first groove 921 is 90°, and there are two first grooves 921, which are symmetrically arranged on both sides of the first elastic sheet 92.

[0121] The central angle of the second groove 931 is 90°. There are two second grooves 931, which are symmetrically arranged on both sides of the second elastic sheet 93.

[0122] Two first grooves 921 and two second grooves 931 are offset axially from the first elastic sheet 92. The orthographic projection of the second groove 931 on the first elastic sheet 92 and the first groove 921 are arranged alternately.

[0123] The first groove 921 and the second groove 931 have the same shape. The depth of the first groove 921 gradually increases and then decreases circumferentially on the first elastic sheet 92, reaching its maximum depth at its central position. Similarly, the depth of the second groove 931 gradually increases and then decreases circumferentially on the second elastic sheet 93, reaching its maximum depth at its central position.

[0124] Thus, for every 90° rotation of the first elastic element 9, the intrinsic frequency of the main oscillator 600 changes by one cycle. The intrinsic frequency of the main oscillator 600 gradually changes from its maximum intrinsic frequency to its minimum intrinsic frequency, and then back to its maximum intrinsic frequency. The desired maximum and minimum intrinsic frequencies of the main oscillator 600 can be set by controlling the thickness of the first elastic sheet 92 and the second elastic sheet 93, and the depth of the first groove 921 and the second groove 931. The maximum intrinsic frequency can be 1000Hz, and the minimum intrinsic frequency can be 100Hz. Furthermore, the intrinsic frequency of the main oscillator 600 can be made to change linearly with the rotation angle of the first elastic element 9 by controlling the shape of the first groove 921 and the second groove 931.

[0125] In one illustrative embodiment, such as Figure 9 As shown, the base 1 includes a base body 11 and a support column 12. The base body 11 is disc-shaped. The support column 12 extends vertically upward from the base body 11. The support column 12 is coaxially arranged with the first rotating shaft 10. The diameter of the support column 12 is larger than the inner diameter of the cylinder 91. The top end of the support column 12 abuts against the cylinder 91 and supports the first elastic member 9. The end face of the top end of the support column 12 can be an arc surface that arches upward in the middle, such as a spherical surface, which can reduce the friction between the support column 12 and the cylinder 91, allowing the first elastic member 9 to rotate more smoothly. In this embodiment, the first rotating shaft 10 is constructed as a screw and is threadedly connected to the top end of the support column 12, and the cylinder 91 of the first elastic member 9 is sleeved on the screw shank.

[0126] like Figure 4 As shown, the main oscillator 600 includes a lower counterweight 6 and an upper counterweight 12. Both the lower counterweight 6 and the upper counterweight 12 are made of a high-density metal material. Figure 6 , 7As shown, the top center of the lower counterweight 6 is recessed downwards to form a mounting cavity 61. The mounting cavity 61 has an upward-facing opening. A first straight hole 62 extends downwards from the center of the bottom end of the mounting cavity 61 to the bottom end of the lower counterweight 6. A support column 12 is inserted into the first straight hole 62 from the bottom end of the first straight hole 62. The outer diameter of the support column 12 is smaller than the inner diameter of the first straight hole 62. There is an annular gap between the support column 12 and the first straight hole 62, so that the main oscillator 600 will not contact the support column 12 during vibration.

[0127] like Figure 3 As shown, the top of the upper counterweight 12 covers the top of the lower counterweight 6, and the upper counterweight 12 can cover the upward-facing opening of the mounting cavity 61. The upper counterweight 12 and the lower counterweight 6 are detachably connected. In this embodiment, the upper counterweight 12 and the lower counterweight 6 are connected by a first screw 13.

[0128] In this way, before the upper counterweight 12 is assembled onto the lower counterweight 6, the bearing sleeve 7, the thrust bearing 8, and the first elastic element 9 can be installed into the mounting cavity 61 through the upward opening of the mounting cavity 61. Then, the sleeve of the first elastic element 9 is assembled onto the first rotating shaft 10. Finally, the assembly of the upper counterweight 12 and the lower counterweight 6 is completed, so that the upper counterweight 12 can cover the upward opening of the mounting cavity 61, making the assembly more convenient.

[0129] In one illustrative embodiment, the lower counterweight 6 and the upper counterweight 12 are constructed as vertical cylinders. The lower counterweight 6 and the upper counterweight 12 have the same diameter. Both the lower counterweight 6 and the upper counterweight 12 are coaxially arranged with the first rotating shaft 10. The mass of the lower counterweight 6 can be greater than the mass of the upper counterweight 12, which can lower the center of gravity of the main oscillator 600.

[0130] The lower counterweight 6 and the upper counterweight 12 are constructed in cylindrical shape, and the main oscillator 600 is also constructed in a vertical cylindrical shape. The center of gravity of the main oscillator 600 is located on the axis of the first rotating shaft 10, making the force distribution more reasonable.

[0131] In one illustrative embodiment, such as Figure 3 , 8 As shown in Figure 9, the energy harvesting component 102 includes a coil 52 and a magnet 51. The magnet 51 is a permanent magnet, such as a neodymium magnet. The coil 52 is fixedly connected to the bottom of the base body 11 and located inside the base body 11. The two ends of the coil 52 are horizontally oriented. The magnet 51 is disposed on the main oscillator 600. The magnet 51 is fixedly connected to the bottom end of the lower counterweight 6 of the main oscillator 600. The magnet 51 generates a magnetic field, and the closer to the magnet 51, the stronger the magnetic field. The magnet 51 is closer to the upper side of the coil 52 and further away from the lower side of the coil 52. The magnetic field strength at the upper side of the coil 52 is much greater than the magnetic field strength at the lower side of the coil 52.

[0132] When the main oscillator 600 vibrates, it drives the magnet 51 to vibrate. When the magnet 51 vibrates, the magnetic field changes. The coil 52 is located in the changing magnetic field and will generate an induced electromotive force due to electromagnetic induction. In this embodiment, since the magnetic field follows the vibration of the magnet 51, the upper side of the coil 52 cuts the magnetic field lines to generate an induced electromotive force. When the coil 52 is connected to the power circuit, an induced current can be generated in the coil 52, thereby realizing the conversion of the vibration energy of the main oscillator 600 into electrical energy output.

[0133] In one illustrative embodiment, two magnets 51 are provided, spaced apart. The two magnets 51 can be configured as semi-circular plates. The end faces of the two magnets 51 that are close to each other are parallel planes. The ends of the two magnets 51 that are close to each other are provided with opposite magnetic poles; the end of the first magnet 51 near the second magnet 51 is provided with the S pole, and the end of the second magnet 51 near the first magnet 51 is provided with the N pole. The magnetic field strength between the two magnets 51 is relatively large.

[0134] The upper sides of both coils 52 are disposed within the gap between the two magnets 51, and the lower sides of both coils 52 are located below the gap between the two magnets 51. The two ends of each coil 52 face the two magnets 51 respectively. The lower sides of both coils 52 are connected to the base body 11. The two coils 52 are connected in series, and the terminals of the two coils 52 connected by wires have opposite potential polarities, causing the induced electromotive forces generated by the two coils 52 to be superimposed in the same direction.

[0135] Placing two coils 52 between two magnets 51 increases the magnetic field strength at the two coils 52, thereby increasing the induced electromotive force of each coil 52. Simultaneously, superimposing the induced electromotive forces generated by the two coils 52 in the same direction and outputting them allows the output voltage of the vibration energy harvester 100 to be amplified several times.

[0136] In one illustrative embodiment, the energy harvesting assembly 102 further includes a rectifier circuit and a filter circuit. The input terminal of the rectifier circuit is electrically connected via a wire to the non-connected terminals of the two coils 52. The output terminal of the rectifier circuit is electrically connected to the input terminal of the filter circuit. The induced electromotive force generated by the coils 52 is an alternating current (AC) voltage. The induced AC voltages generated by the two coils 52 are superimposed in the same direction and supplied to the input terminal of the rectifier circuit. The rectifier circuit converts the AC voltage input to DC voltage and supplies it to the input terminal of the filter circuit. The filter circuit is used to filter out ripple in the DC voltage. After filtering out the ripple, the filter circuit outputs the DC voltage from its output terminal. The power-consuming device (e.g., a wireless sensor) can then directly utilize the DC voltage output by the filter circuit.

[0137] In one illustrative embodiment, the bottom end of the lower counterweight 6 is recessed upwards to form a mounting groove 63. The mounting groove 63 can be a circular groove. The bottom of the mounting groove 63 is provided with two limiting grooves 64. The two limiting grooves 64 are spaced apart from each other. The upper parts of the two magnets 51 are respectively accommodated in the two limiting grooves 64, and the lower parts of the two magnets 51 are both accommodated in the mounting groove 63.

[0138] The main oscillator 600 also includes a counterweight base plate 3. The counterweight base plate 3 and the lower counterweight block 6 are made of a magnetically conductive material, such as iron or an iron alloy. The counterweight base plate 3 is disc-shaped. The counterweight base plate 3 is connected to the bottom end of the lower counterweight block 6 and covers the opening of the mounting groove 63. The counterweight base plate 3 and the lower counterweight block 6 can be connected together by a second screw 4. The end faces of the bottom ends of the two magnets 51 abut against the upper surface of the counterweight base plate 3. The counterweight base plate 3 has a vertical through-hole 31. The through-hole 31 can be constructed as a straight strip. The through-hole 31 is located directly below the gap between the two magnets 51. The extension direction of the cross-section of the through-hole 31 is perpendicular to the direction of the line connecting the two magnets 51.

[0139] Two coils 52 pass through the clearance through-holes 31 in the counterweight base plate 3 and extend into the mounting grooves 63 of the lower counterweight block 6. When the coils 52 abut against the inner wall of the clearance through-holes 31, they can limit the movement of the main oscillator 600 and prevent the main oscillator 600 from rotating around the first rotating shaft 10.

[0140] In this way, the counterweight base plate 3 presses the two magnets 51 into the two limiting grooves 64 respectively, thereby fixing the two magnetic tapes on the main oscillator 600. At the same time, the counterweight base plate 3 and the lower counterweight block 6 can conduct magnetism, which can reduce magnetic leakage and further enhance the magnetic field strength in the gap between the two magnets 51, and further increase the induced electromotive force of the coil 52.

[0141] Research on vibration energy harvesting devices in related technologies often focuses on harmonic waves, deviating from the actual vibration scenarios of industrial rotating equipment. This results in the device being highly sensitive to deviations between the resonant frequency and the intrinsic frequency, leading to unstable output power. The harmonic wave spectrum differs significantly from the actual vibration spectrum. In the actual spectrum, discussing the vibration energy at a specific frequency is meaningless, as the vibration energy is distributed across different frequency bands. In the case of harmonic waves, when the vibration energy harvesting device is at the resonant frequency, it is as shown in the following formula (1):

[0142]

[0143] Where m is the mass of the oscillator, ω is the angular frequency of vibration, A is the amplitude of the external excitation acceleration, and c is the electromagnetic damping of the mass element vibration, i.e. It can be seen that the smaller the damping, the greater the power. However, in the actual spectrum, as shown in the following formula (2):

[0144]

[0145] Where ω is the external excitation angular frequency, ω0 is the device's intrinsic frequency, β is the electromagnetic damping caused by unit velocity per unit mass, c = mβ, m is the oscillator mass, and A (ω) Let ω be the amplitude density at ω.

[0146] If we uniformly consider energy losses such as air damping in actual vibrations, the air damping c 空 <<1, that is, in the case of simple harmonic waves, when the magnitude of electromagnetic damping decreases to the same order of magnitude as air damping, until it is close to the magnitude of air damping, the output power of the vibration energy harvesting device reaches its maximum value. In the simulation experiment with actual signals as vibration sources, too small electromagnetic damping will lead to extreme sensitivity to frequency. A frequency deviation of a few Hertz from the resonant frequency will cause the power of the vibration energy harvesting device to drop by one to two orders of magnitude. As shown in formula (2), at a frequency 20Hz away from the resonant frequency, the electromagnetic damping β decreases from 0.1 to 0.01, which does not significantly increase the value of the formula within the brackets. Instead, it will reduce the electromagnetic damping c of the vibration of the mass outside the brackets by ten times, thereby reducing the power density at this frequency by about ten times. Conversely, a larger electromagnetic damping, such as β = 100s -1 This will greatly reduce the power's sensitivity to frequency deviation, and also result in a smaller increase in the collected power when the resonant frequency matches the intrinsic frequency well. However, when the electromagnetic damping is too large, such as β = 1000s... -1 In reality, a narrow resonant frequency range in the signal will not be able to produce a significant resonance phenomenon in the device.

[0147] In this embodiment, when the coil 52 generates an induced current, it applies a magnetic force to the magnet 51 in the opposite direction of its motion, thereby hindering the vibration of the main oscillator 600 and forming electromagnetic damping on the main oscillator 600. The electromagnetic damping of the main oscillator 600 can be adjusted by increasing or decreasing the number of turns of the coil 52 or by adjusting the magnetic field strength of the magnet 51. The electromagnetic damping c of the main oscillator 600 is set to 100 N·s / m, so that in the simulation experiment with actual signals, the resonance range of the main oscillator 600 reaches 30 Hz, and the resonance phenomenon is obvious. This not only stabilizes the output power of the vibration energy harvester 100, but also ensures that the vibration energy harvester 100 has a high output power when the main oscillator 600 resonates.

[0148] In one illustrative embodiment, such as Figure 1As shown, the vibration energy harvester 100 also includes a speed change assembly 105. The speed change assembly 105 can be a gearbox. The speed change assembly 105 can be mounted on the main oscillator 600, further increasing the vibration energy. The speed change assembly 105 is connected to the first elastic element 9 and the power conversion assembly 103. The speed change assembly 105 can increase the torque output by the power conversion assembly 103 and transmit the increased torque to the first elastic element 9 to drive its rotation.

[0149] Since the power source of the power conversion component 103 is mechanical vibration, the torque it directly outputs is usually small. The speed change component 105 increases the torque output by the power conversion component 103 and then sends it to the first elastic element 9 to drive the first elastic element 9 to rotate. This ensures that the first elastic element 9 can overcome friction and rotate, thus improving the reliability of the vibration energy harvester 100.

[0150] In one illustrative embodiment, such as Figures 11-13 As shown, the transmission assembly 105 includes an internal gear ring 15, a central gear 17, multiple planetary gears 16, a planet carrier 14, a second rotating shaft 11, and a third rotating shaft 20. The internal gear ring 15 is fixedly connected to the top of the upper counterweight 12 of the main oscillator 600. The outer diameter of the internal gear ring 15 can be the same as the diameter of the upper counterweight 12. The internal gear ring 15 is coaxially arranged with the first rotating shaft 10. The central gear 17 is disposed inside the internal gear ring 15. The central gear 17 is coaxially arranged with the internal gear ring 15. The number of planetary gears 16 can be three. Multiple planetary gears 16 are disposed between the internal gear ring 15 and the central gear 17, and the multiple planetary gears 16 are evenly distributed in the circumferential direction of the central gear 17. Each planetary gear 16 meshes with both the internal gear ring 15 and the central gear 17.

[0151] The planet carrier 14 can be constructed in the shape of a triangular plate. The planet carrier 14 is positioned on the side of the planetary gear 16 near the main oscillator 600. Multiple spindles 141 are mounted on the planet carrier 14, all parallel to the first rotating shaft 10. The number of spindles 141 is the same as the number of planetary gears 16. The multiple planetary gears 16 are respectively mounted on the multiple spindles 141. The planetary gears 16 can rotate freely around the spindles 141, thereby achieving a rotational connection between the planet carrier 14 and each planetary gear 16.

[0152] The upper counterweight 12 of the main oscillator 600 has a second straight hole 121 that runs vertically through it. The second straight hole 121 is coaxial with the first straight hole 62. The inner diameter of the second straight hole 121 is larger than the outer diameter of the second rotating shaft 11, which passes through the second straight hole 121. One end of the second rotating shaft 11 is connected to the planetary carrier 14, and the other end is connected to the first elastic element 9. The second rotating shaft 11 is coaxial with the first rotating shaft 10. The second rotating shaft 11 can be a hollow shaft. The first elastic element 9 has a first mounting hole 94, and the planetary carrier 14 has a second mounting hole 142. The two ends of the second rotating shaft 11 are respectively inserted into the first mounting hole 94 of the first elastic element 9 and the second mounting hole 142 of the planetary carrier 14. The second rotating shaft 11 and the first mounting hole 94 can be an interference fit. The second rotating shaft 11 and the second mounting hole 142 can be an interference fit.

[0153] One end of the third rotating shaft 20 is connected to the middle of the central gear 17 and is coaxially arranged with the central gear 17. The central gear 17 may be mounted on the third rotating shaft 20. The connection between the central gear 17 and the third rotating shaft 20 may be an interference fit or a keyed connection. The third rotating shaft 20 extends upward from the middle of the central gear 17. The end of the third rotating shaft 20 facing away from the central gear 17 is connected to the power conversion assembly 103. The power conversion assembly 103 supplies torque to the third rotating shaft 20.

[0154] Thus, the internal gear ring 15, the central gear 17, multiple planetary gears 16, the planet carrier 14, the second shaft 11, and the third shaft 20 form a coaxial planetary gear 16 transmission. The third shaft 20 is the input shaft of this planetary gear 16 transmission, and the second shaft 11 is the output shaft. The power conversion assembly 103 transmits torque to the third shaft 20 to drive its rotation. The third shaft 20 drives the central gear 17 to rotate, which in turn drives the planetary gears 16 to rotate. The planetary gears 16 then drive the planet carrier 14 to rotate, which in turn drives the second shaft 11 to rotate. The second shaft 11 then drives the first elastic element 9 to rotate. The torque is increased during the transmission from the third shaft 20 to the second shaft 11.

[0155] In one illustrative embodiment, the central gear 17 and the planetary gear 16 both have 14 teeth, and the module of both the central gear 17 and the planetary gear 16 is 0.5. The internal gear ring 15 has 42 teeth and the module of the internal gear ring 15 is 0.5.

[0156] In this way, the transmission ratio of the transmission component 105 is 4:1, and the torque can be increased by nearly four times.

[0157] In an illustrative embodiment, the second rotating shaft 11 includes two sub-shafts 111. The sub-shafts 111 are constructed as straight strips. The cross-section of each sub-shaft 111 is arc-shaped, and the arc-shaped cross-sections of the two sub-shafts 111 are concentric. The two sub-shafts 111 are symmetrically arranged about the rotation axis of the first elastic member 9. The first elastic member 9 has two first mounting holes 94, both of which have arc-shaped cross-sections. The planetary carrier 14 has two second mounting holes 142, both of which have arc-shaped cross-sections. One end of each sub-shaft 111 is inserted into one of the two first mounting holes 94, and the other end of each sub-shaft 111 is inserted into one of the two second mounting holes 142.

[0158] Connecting the first elastic element 9 and the planetary carrier 14 with two sub-shafts 111 enables precise alignment between them, reducing assembly difficulty. Simultaneously, splitting the second rotating shaft 11 into two sub-shafts 111 weakens its structural strength, allowing it to undergo elastic deformation and reducing its impact on the vibration of the main oscillator 600.

[0159] In one illustrative embodiment, such as Figure 11 As shown, the transmission assembly 105 also includes a cover plate 18. The cover plate 18 can be constructed as a circular flat plate. The cover plate 18 covers the end of the internal gear ring 15 facing away from the main oscillator 600. The cover plate 18 is connected to the internal gear ring 15. The cover plate 18 prevents the central gear 17 and planetary gear 16 from disengaging from the internal gear ring 15. A first through hole 181 is provided on the cover plate 18. The first through hole 181 is located in the middle of the cover plate 18 and is coaxially arranged with the third rotating shaft 20. The cover plate 18, the internal gear ring 15, and the upper counterweight 12 can be connected together by a third screw 19.

[0160] like Figures 15-17 As shown, the power conversion assembly 103 includes a housing 2, a rolling bearing 22, a rotating component 23, a second elastic component 27, and a friction plate 21. The housing 2 is cylindrical. One end of the housing 2 is connected to the base body 11 of the base 1. The housing 2 and the base body 11 can be threaded together. The vibration frequency conversion assembly 101 and the energy harvesting assembly 102 are located inside the housing 2. A mounting base 202 is provided at the end of the housing 2 facing away from the base 1. The mounting base 202 can be constructed as an annular plate. The mounting base 202 is provided with a third mounting hole 203. The third mounting hole 203 is a through hole penetrating the middle of the mounting base 202. The rolling bearing 22 is disposed in the third mounting hole 203, and the outer ring of the rolling bearing 22 is interference-fitted with the third mounting hole 203, so that the outer ring of the rolling bearing 22 is fixed on the mounting base 202 of the housing 2. The rolling bearing 22 is coaxially arranged with the third rotating shaft 20.

[0161] The rotating component 23 includes a turntable 231. The turntable 231 is disc-shaped. The turntable 231 is disposed within the inner ring of the rolling bearing 22, and is interference-fitted with the inner ring of the rolling bearing 22. The turntable 231 is fixed to the inner ring of the rolling bearing 22. The turntable 231 is rotatably connected to the housing 2 via the rolling bearing 22. The axis of the turntable 231 is coaxial with the axis of the rolling bearing 22.

[0162] The friction plate 21 is disc-shaped. It is positioned between the turntable 231 and the cover plate 18. The friction plate 21 and the turntable 231 are coaxially aligned. The friction plate 21 abuts against the end of the turntable 231 near the cover plate 18. The coefficient of friction between the friction plate 21 and the turntable 231 is preferably 0.2. A second through hole 211 is provided in the center of the friction plate 21, and this second through hole 211 is coaxially aligned with the third rotating shaft 20.

[0163] The third rotating shaft 20 passes through the second through hole 211 of the friction plate 21 and the first through hole 181 of the cover plate 18. The inner diameters of both the first through hole 181 and the second through hole 211 are larger than the diameter of the third rotating shaft 20. The end of the third rotating shaft 20 facing away from the central gear 17 is fixedly connected to the turntable 231. A shaft hole can be provided in the middle of the turntable 231, and the end of the third rotating shaft 20 is inserted into the shaft hole with an interference fit.

[0164] The second elastic element 27 is disposed between the cover plate 18 and the friction plate 21. One end of the second elastic element 27 is connected to the middle of the friction plate 21, and the other end of the second elastic element 27 is connected to the middle of the cover plate 18. The second elastic element 27 is elastic. The second elastic element 27 elastically supports the friction plate 21. When the second elastic element 27 is in a compressed state, there is slight pressure between the friction plate 21 and the turntable 231. The second elastic element 27 is configured to undergo elastic deformation in the axial direction of the third rotating shaft 20 and torsional elastic deformation in the circumferential direction of the third rotating shaft 20. The elastic deformation of the second elastic element 27 in the axial direction of the third rotating shaft 20 can be tensile elastic deformation and compressive elastic deformation. When the two ends of the second elastic element 27 are compressed, the second elastic element 27 will not only be shortened, but will also undergo torsional deformation, causing one end of the second elastic element 27 to rotate relative to the other end of the second elastic element 27 in the circumferential direction of the third rotating shaft 20.

[0165] When the main oscillator 600 vibrates under the excitation of the vibration source, it drives the cover plate 18 to vibrate, causing a change in the distance between the cover plate 18 and the friction plate 21. This causes the second elastic element 27 to undergo elastic deformation. The second elastic element 27 applies a normal pressure parallel to the axial direction of the third rotating shaft 20 and a torque in the direction surrounding the third rotating shaft 20 to the friction plate 21. This results in the friction plate 21 generating normal vibration and angular torsional vibration, and also causes the friction plate 21 to apply pressure and torsional frictional force to the turntable 231. Because there is a phase difference between the normal pressure applied to the friction plate 21 by the second elastic element 27 and the torsional angle of the second elastic element 27, the turntable 231 can receive a torque in a fixed direction applied by the friction plate 21. This torque drives the turntable 231 to rotate in a fixed direction. In other words, part of the vibration energy of the main oscillator 600 is converted into torque that causes the turntable 231 to rotate.

[0166] The following section explains in detail why the friction plate 21 applies a torque in a fixed direction to the turntable 231.

[0167] Let x be the distance by which the main oscillator 600 deviates from its equilibrium position, N be the normal pressure exerted by the second elastic element 27 on the friction plate 21, θ be the torsional angle of the second elastic element 27, k1 be the normal elastic coefficient of the second elastic element 27, k2 be the torsional elastic coefficient of the second elastic element 27, k3·1m be the torque generated by the second elastic element 27 per unit compression distance, J be the moment of inertia of the torsional counterweight, and β be the torsional resistance coefficient. Then, the following two equations can be obtained:

[0168] N = k1x(3)

[0169]

[0170] Equation (3) is a linear equation, which can be used to analyze a single-frequency scenario. Let the angular frequency of x be ω and the amplitude of θ be Θ, then equation (4) is the forced vibration equation for sinusoidal excitation. θ will lag behind x by one phase.

[0171]

[0172] like Figures 24-26 As shown, the three possible x-θ phase diagrams are all clockwise. Since all three are clockwise, they do not affect the conclusion; without loss of generality, let's assume the state is the same as... Figure 24 The first phase diagram shown is the same state. Figure 27 The N-θ phase diagram for this state is shown.

[0173] For example Figure 28 The above, Figure 28The areas marked with "+" represent areas where the angular velocity of the rotating counterweight is positive, and the direction of the frictional force applied by friction plate 21 to turntable 231 is positive. The areas marked with "-" represent areas where the angular velocity of the rotating counterweight is negative, and the direction of the frictional force applied by friction plate 21 to turntable 231 is negative. The area S of the areas marked with "+" represents the integral of N over t within that area, and the resulting frictional impulse torque μlS. + Conversely, μlS - Where l is the equivalent force arm, and μ is the coefficient of friction between the friction plate 21 and the turntable 231, the average frictional torque applied by the friction plate 21 to the turntable 231 can be obtained as follows: And for Figures 24-26 In all three cases, S + -S - If the value is greater than 0, the direction of the average frictional torque applied by the friction plate 21 to the turntable 231 is constant.

[0174] In one illustrative embodiment, the second elastic element 27 includes a first ring 271 and a plurality of spring bars 272. The first ring 271 is connected to the cover plate 18 and located at one end of the cover plate 18 near the friction plate 21. A third rotating shaft 20 passes through the first ring 271, and the first ring 271 is coaxially arranged with the third rotating shaft 20. The inner diameter of the first ring 271 is larger than the diameter of the third rotating shaft 20.

[0175] The spring strip 272 is elastic and capable of elastic deformation. The spring strip 272 can be a strip-shaped metal sheet. One end of the spring strip 272 is connected to the first ring 271, and the other end is connected to the friction plate 21. The spring strip 272 can be helical. Multiple spring strips 272 extend helically from the first ring 271 to the friction plate 21, and the helical directions of the multiple spring strips 272 are the same. The multiple spring strips 272 are evenly distributed circumferentially on the third rotating shaft 20.

[0176] Thus, when the distance between the friction plate 21 and the cover plate 18 changes, the length of the second elastic element 27 in the axial direction of the third rotating shaft 20 changes, and multiple spring bars 272 will jointly apply a normal elastic force parallel to the axial direction of the third rotating shaft 20 and a torque in the circumferential direction of the third rotating shaft 20 to the friction plate 21.

[0177] In one illustrative embodiment, such as Figure 17 As shown, a protrusion 212 protruding towards one side of the turntable 231 is provided in the middle of the friction plate 21. The end face of the top of the protrusion 212 abuts against the plate surface of the turntable 231 facing the friction plate 21. The end face of the top of the protrusion 212 and the plate surface of the turntable 231 facing the friction plate 21 can be parallel planes.

[0178] The friction plate 21 applies frictional force to the turntable 231 through the protrusion 212 to drive the turntable 231 to rotate. This prevents other parts of the friction plate 21, except for the protrusion 212, from contacting the housing 2 or the rolling bearing 22, thus avoiding interference from the housing 2 or the rolling bearing 22 with the vibration of the friction plate 21.

[0179] In one illustrative embodiment, such as Figure 34 As shown, the rotating component 23 also includes a positioning plate 232 and a connecting portion 233. The positioning plate 232 is disposed on the side of the turntable 231 facing away from the friction plate 21. The positioning plate 232 can be constructed in a disc shape. The positioning plate 232 is coaxially arranged with the turntable 231. The positioning plate 232 can be made of a lightweight material and can be constructed as a hollow plate. The positioning plate 232 has a very small mass. The connecting portion 233 connects the positioning plate 232 and the turntable 231, thereby fixing the positioning plate 232 and the turntable 231 together. Multiple connecting portions 233 can be provided and distributed on the edges of the positioning plate 232 and the turntable 231. The connecting portion 233 can be constructed as a micro-spring to elastically support the positioning plate 232. The side of the positioning plate 232 facing away from the turntable 231 is provided with a slot 2321. The slot 2321 is eccentrically positioned on the positioning plate 232, meaning it is not located at the exact center of the positioning plate 232. The slot 2321 rotates with the rotating component 23, and its movement trajectory is circular.

[0180] The vibration frequency sensing component 104 includes an oscillator ring 24, a top plate 26, and a blocking member 25. The oscillator ring 24 includes an annular base 241 and multiple auxiliary oscillators 242. The annular base 241 is circular in shape. The annular base 241 is connected to the end of the outer shell 2 facing away from the base 1. The annular base 241 is coaxially arranged with the outer shell 2. The annular base 241 and the outer shell 2 can be connected by a snap-fit ​​connection. The multiple auxiliary oscillators are arranged within the annular base 241 and sequentially around the circumference of the annular base 241. The auxiliary oscillators 242 are elastically connected to the annular base 241. The multiple auxiliary oscillators 242 can be distributed in a spoke-like pattern within the annular base 241. The local frequencies of the multiple auxiliary oscillators 242 are different from each other. A locking plate 232 is located within the oscillator ring 24.

[0181] A top plate 26 covers one end of the annular base 241 facing away from the outer casing 2. The top plate 26 is fixedly connected to the outer casing 2. The top plate 26 can be a circular plate. The top plate 26 is located on the side of the positioning plate 232 facing away from the turntable 231 and on the side of the auxiliary vibrator 242 facing away from the positioning plate 232. There is a gap between the top plate 26 and the auxiliary vibrator 242. The mass of the auxiliary vibrator 242 can be set to be relatively small.

[0182] The blocking component 25 includes a column 251 and multiple blocking plates 252. The column 251 can be constructed as a vertically extending straight strip structure. One end of the column 251 is connected to the middle of the top plate 26, and the other end of the column 251 extends to a position near the positioning plate 232. The column 251 and the positioning plate 232 are coaxially arranged. The blocking plates 252 are constructed as plate-like structures, and can be constructed as approximately triangular plates. The blocking plates 252 are vertically arranged. The blocking plates 252 are elastically connected to the end of the column 251 near the positioning plate 232. The blocking plates 252 and the column 251 can be connected by an elastic sheet. The multiple blocking plates 252 are distributed in a spoke-like pattern around the column 251. The multiple blocking plates 252 are arranged in a ring directly above the movement trajectory of the slot 2321 of the positioning plate 232. During the rotation of the positioning plate 232, the slot 2321 passes directly below the multiple blocking plates 252 in sequence. The number of auxiliary vibrators 242 is the same as the number of blocking plates 252, with each auxiliary vibrator 242 corresponding to a blocking plate 252. Each auxiliary vibrator 242 extends from the annular base 241 to the side of its corresponding blocking plate 252 facing away from the positioning plate 232. When vibrating, the auxiliary vibrator 242 vibrates in a vertical plane, striking its corresponding blocking plate 252, causing the blocking plate 252 to shift towards the side closer to the positioning plate 232. When the auxiliary vibrator 242 resonates, its vibration amplitude reaches its maximum value, and the degree to which its corresponding blocking plate 252 shifts towards the side closer to the positioning plate 232 is also the maximum. The blocking plate 252 is configured so that it can only be struck by its corresponding auxiliary vibrator 242 to the extent that it can shift to the insertion slot 2321 when the auxiliary vibrator 242 resonates. That is, the secondary oscillator 242 can only strike its corresponding blocking piece 252 into the insertion slot 2321 when resonance occurs. The first elastic member 9 is configured such that when the slot 2321 is rotated to a position where the eigenfrequency of the main oscillator 600 is equal to the eigenfrequency of the secondary oscillator 242 corresponding to the blocking piece 252, the first elastic member 9 can rotate to a position where the eigenfrequency of the main oscillator 600 is equal to the eigenfrequency of the secondary oscillator 242 corresponding to the blocking piece 252.

[0183] Thus, after the vibration energy harvester 100 receives the vibration output from the vibration source, the rotating component 23 rotates, and drives the first elastic component 9 to rotate through the speed change component 105. The rotating component 23 and the first elastic component 9 rotate synchronously. All the secondary vibrators 242 also vibrate. The secondary vibrator 242 whose intrinsic frequency is closest to the external excitation frequency resonates. The amplitude of this secondary vibrator 242 is the largest, causing the blocking plate 252 corresponding to this secondary vibrator 242 to shift to the maximum extent towards the positioning plate 232 and press the positioning plate 232. When the rotating component 23 rotates, the slot 2321 moves along its annular motion trajectory. When the slot 2321 moves below the blocking plate 252 corresponding to the resonant secondary vibrator 242, the blocking plate 252 is inserted into the slot 2321 under the impact of the secondary vibrator 242. After the blocking plate 252 is inserted into the slot 2321, it can lock the positioning plate 232, causing the positioning plate 232 and the first elastic component 9 to stop rotating simultaneously. At this time, the first elastic element 9 stops at the position where the eigenfrequency of the main oscillator 600 is equal to the eigenfrequency of the resonant secondary oscillator 242. Since the eigenfrequency of the resonant secondary oscillator 242 is equal to the excitation frequency, the main oscillator 600 resonates because its eigenfrequency is equal to the excitation frequency. The main oscillator 600 is locked in the resonant state, and the output power of the vibration energy harvester 100 is stable and large.

[0184] After the excitation frequency changes, the sub-oscillator 242 corresponding to the blocking piece 252 currently inserted into the slot 2321 stops resonating. Under the action of the restoring elastic force, the blocking piece 252 disengages from the slot 2321, and the rotating member 23 and the first elastic member 9 rotate again. Meanwhile, the secondary oscillator 242, whose intrinsic frequency is closest to the changed excitation frequency, resonates, causing the blocking plate 252 corresponding to the secondary oscillator 242 to shift to the maximum extent towards the positioning plate 232 and press the positioning plate 232. When the slot 2321 moves again below the blocking plate 252 corresponding to the resonating secondary oscillator 242, the blocking plate 252 can be inserted into the slot 2321, causing the positioning plate 232 and the first elastic member 9 to stop rotating simultaneously. At this time, the intrinsic frequency of the main oscillator 600 is adjusted to be equal to the intrinsic frequency of the resonating secondary oscillator 242, that is, the intrinsic frequency of the main oscillator 600 is equal to the changed excitation frequency and resonates. The main oscillator 600 is locked in the resonance state again, and the vibration energy harvester 100 returns to a state with stable and large output power.

[0185] Therefore, the eigenfrequency of the main oscillator 600 can change with the excitation frequency, so that the main oscillator 600 can always remain in a resonant state, and the vibration energy harvester 100 can obtain a stable and large output power regardless of the change of the excitation frequency.

[0186] In one illustrative embodiment, the end of the blocking piece 252 facing the card slot 232 may be configured as a pointed tip, and the portion of the blocking piece 252 that can be inserted into the card slot 2321 is its pointed tip.

[0187] The tip can be inserted more smoothly into the slot 2321 of the card slot plate 232, reducing the possibility of the blocking piece 252 failing to be inserted into the slot 2321.

[0188] In an illustrative embodiment, the sub-oscillator 242 includes a first oscillator 2421 and a second oscillator 2422. The first oscillator 2421 is elastically connected to an annular base 241. The second oscillator 2422 is elastically connected to the first oscillator 2421. The first oscillator 2421 and the second oscillator 2422 are arranged sequentially in a radially inward direction from the annular base 241. The first oscillator 2421 and the second oscillator 2422 can be constructed as a vertical flat plate structure. The first oscillator 2421 and the second oscillator 2422 in the same sub-oscillator 242 have the same eigenfrequency. The mass of the first oscillator 2421 is greater than the mass of the second oscillator 2422. When resonance occurs, the second oscillator 2422 strikes a blocking plate 252, while the first oscillator 2421 does not contact the blocking plate 252. The first oscillator 2421 and the second oscillator 2422 oscillate vertically during vibration.

[0189] Since the first oscillator 2421 and the second oscillator 2422 in the same sub-oscillator 242 have the same eigenfrequency, the first oscillator 2421 and the second oscillator 2422 will resonate synchronously and amplify the resonance amplitude, thereby increasing the deflection stroke of the blocking plate 252.

[0190] In an illustrative embodiment, the secondary oscillator 242 further includes a first elastic rod 2423 and a second elastic rod 2424. The first elastic rod 2423 is disposed between the annular base 241 and the first oscillator 2421, with its two ends respectively connected to the sides of the annular base 241 and the first oscillator 2421 that are close to each other. The second elastic rod 2424 is disposed between the first oscillator 2421 and the second oscillator 2422, with its two ends respectively connected to the sides of the first oscillator 2421 and the second oscillator 2422 that are close to each other. The first elastic rod 2423 and the second elastic rod 2424 are elastic and can undergo bending elastic deformation.

[0191] The first elastic rod 2423 elastically connects the first oscillator 2421 to the annular base 241, and the second elastic rod 2424 elastically connects the first oscillator 2421 to the second oscillator 2422.

[0192] In one illustrative embodiment, a buffer membrane is disposed on the surface of the blocking sheet 252 facing the sub-oscillator 242. The buffer membrane may be made of a flexible material.

[0193] When the secondary vibrator 242 strikes the buffer membrane, the buffer membrane cushions the impact of the secondary vibrator 242, allowing the blocking plate 252 to deflect stably toward the positioning plate 232.

[0194] In an illustrative embodiment, a plurality of secondary oscillators 242 are uniformly distributed circumferentially on the annular base 241. The intrinsic frequencies of the multiple secondary oscillators 242 increase uniformly along their arrangement direction. For example, there are 30 secondary oscillators 242, arranged in a ring from the 1st to the 30th. From the 1st to the 30th secondary oscillator 242, the intrinsic frequencies of the secondary oscillators 242 increase sequentially by the same amount. The intrinsic frequencies from the 1st to the 30th secondary oscillator 242 can increase sequentially from 100Hz to 1000Hz, with each increase being 30Hz. The range of variation of the intrinsic frequency of the main oscillator 600 corresponds to the range of variation of the intrinsic frequencies of the multiple secondary oscillators 242; the range of variation of the intrinsic frequency of the main oscillator 600 can be from 100Hz to 1000Hz.

[0195] In this embodiment, the eigenfrequency distribution of the multiple secondary oscillators 242 with respect to angular position is shown in the following table:

[0196]

[0197] The vibration energy harvester 100 in this embodiment can extract and compare the vibration spectrum through a large number of miniature secondary oscillators 242 resonant amplification and mechanical comparators. Through a purely mechanical structure, it adjusts the intrinsic frequency of the main oscillator 600 under external excitation, automatically changing the intrinsic frequency to approach the excitation frequency of the external excitation. The intrinsic frequencies of the secondary oscillators 242 are spaced 30Hz apart. Ultimately, the error between the intrinsic frequency of the main oscillator 600 and the external main excitation frequency is controlled within ±15Hz, and the frequency adaptation range is 115-985Hz. When the main oscillator 600 is in a resonant or near-resonant state, the vibration energy harvesting efficiency of the vibration energy harvester 100 in this embodiment is significantly improved compared to energy harvesting devices of the same volume with fixed intrinsic frequencies.

[0198] Based on a simulation experiment using a real-world application scenario, an excitation acceleration signal from the operation of a real rotating device was transmitted to the vibration energy harvester 100, and the following results were obtained: Figure 29 , 30 The time-domain and frequency-domain plots of the excitation acceleration signal are displayed. In the simulation experiment, the magnetic field strength of magnet 51 is set to 2T, the total length of the wire of coil 52 is set to 22.5m, the resistance of the wire of coil 52 is about 2Ω, the equivalent resistance of the external electrical appliance is 18Ω, and the total mass of the main oscillator 600 is 0.5kg.

[0199] like Figure 31 As shown, the main external excitation frequency is 543Hz, and when the first elastic element 9 is at an elastic coefficient of 5.83×10⁻⁶, the frequency is 543Hz. 6 At a position of N / m, the natural frequency of the main oscillator 600 is 583Hz, at which point the main oscillator 600 is in a resonant state, and the power of the vibration energy harvested from the main oscillator 600 is 85mW. For example... Figure 32 As shown, when the intrinsic frequency of the main oscillator 600 shifts by 15Hz, the vibration energy harvesting power of the main oscillator 600 is 46mW and 48mW, respectively.

[0200] In dealing with similar scenarios, the energy harvesting power of the vibration energy harvester 100 to the main oscillator 600 in this embodiment is between 55% and 100% under resonance conditions. For example... Figure 33 As shown, without an adaptive frequency sensing and adjustment mechanism, the mass of the oscillator in a vibration energy harvesting device of the same volume can reach 0.8 kg. When dealing with uncertain excitation frequencies of 100-1000 Hz, electromagnetic damping is necessary to ensure stable energy harvesting power. It should be about 10 times that of the vibration energy harvester 100 in this embodiment to ensure that the energy harvesting power is maintained at 6-11mW when the main excitation frequency is between 400 and 700Hz.

[0201] Under the same volume (a cylinder with a diameter of 40mm and a height of 66mm) and application scenario, the vibration energy harvester 100 in this embodiment can provide approximately 7 times the energy harvesting power of a typical vibration energy harvester 100, and has a wider frequency adaptation range (100-1000Hz). The output power of the vibration energy harvester 100 is stable at around 50mW, which is much greater than the output power of a battery when powered by a battery, and can greatly improve the sampling frequency of the wireless sensor. It is also smaller in size and can be installed at any angle.

[0202] In another illustrative embodiment, the energy harvesting assembly 102 includes a piezoelectric ceramic (not shown). The piezoelectric ceramic is sandwiched between the bottom end of the main oscillator 600 and the upper surface of the base 1. Piezoelectric ceramic is a functional ceramic material capable of converting mechanical energy and electrical energy into each other. The piezoelectric ceramic may be fixed to the base 1. When the main oscillator 600 vibrates, it compresses the piezoelectric ceramic, causing the piezoelectric effect to occur, thereby converting the mechanical energy of the main oscillator 600's vibration into electrical energy output.

[0203] The power conversion assembly 103 includes an ultrasonic motor (not shown). The ultrasonic motor is electrically connected to the energy harvesting assembly 102. A portion of the electrical energy generated by the energy harvesting assembly 102 is supplied to the ultrasonic motor. The ultrasonic motor is also drively connected to the first elastic member 9. The ultrasonic motor drives the first elastic member 9 to rotate after the power is turned on.

[0204] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0205] Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first," "second," etc., may explicitly or implicitly include at least one of those features.

[0206] In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise expressly and specifically limited.

[0207] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral part; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; it can be the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0208] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0209] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0210] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A vibration energy harvester, characterized in that, include: Vibration frequency converter components include: The base is provided with a first pivot; and, The first elastic element includes a cylinder sleeved on the first rotating shaft and capable of rotating around the first rotating shaft, and a first elastic sheet extending radially outward from the cylinder. The thickness of the first elastic sheet is uneven in the circumferential direction of the cylinder. The first elastic element further includes a second elastic sheet of uneven thickness, and the first elastic sheet and the second elastic sheet extend radially outward from opposite ends of the cylinder, respectively; The main oscillator is rotatably connected to the first elastic sheet and is configured to not rotate relative to the base; the main oscillator is provided with a mounting cavity and a first straight hole extending from the mounting cavity to the bottom end of the main oscillator, and the first rotating shaft extends into the mounting cavity along the first straight hole; The vibration frequency conversion assembly also includes two bearing sleeves respectively disposed at the top and bottom of the mounting cavity, and thrust bearings respectively located in the two bearing sleeves; The first elastic sheet and the second elastic sheet are disposed between the two thrust bearings, and the ends of the first elastic sheet and the second elastic sheet that are opposite to each other abut against the two thrust bearings respectively; A power conversion assembly is used to convert the vibration transmitted to the power conversion assembly into torque that drives the first elastic element to rotate; the power conversion assembly includes: a housing connected to the base; A transmission assembly, which is connected to the first elastic element and the power conversion assembly, is used to boost the torque output by the power conversion assembly and then transmit it to the first elastic element. A vibration frequency sensing component is used to detect the excitation frequency of the vibration applied by the vibration source, and to prevent the first elastic element from rotating when the first elastic element rotates to a position where the eigenfrequency of the main oscillator reaches the excitation frequency. The vibration frequency sensing component includes: an oscillator ring, including an annular base connected to the outer shell and multiple secondary oscillators elastically connected to the annular base, wherein the eigenfrequency of the multiple secondary oscillators is different from that of each other; And an energy harvesting component, used to convert the vibration energy of the main oscillator into electrical energy and output it.

2. The vibration energy harvester according to claim 1, characterized in that, The first elastic sheet is annular in shape, and one end of the first elastic sheet facing the second elastic sheet has a first groove distributed in a fan-shaped annular pattern, with the depth of the first groove gradually changing upwards from the circumference of the first elastic sheet; and / or, The second elastic sheet is constructed as a ring, and a second groove distributed in a fan-shaped ring is provided at one end of the second elastic sheet facing the first elastic sheet. The depth of the second groove gradually changes from circumferential to circumferential on the second elastic sheet.

3. The vibration energy harvester according to claim 2, characterized in that, The central angle of the first groove is 90°, and there are two first grooves, which are symmetrically arranged on both sides of the first elastic sheet. There are two second grooves, which are symmetrically arranged on both sides of the second elastic sheet; The first groove and the second groove are offset in the axial direction of the first elastic sheet, and the first groove and the second groove have the same shape.

4. The vibration energy harvester according to claim 1, characterized in that, The base includes a base body and a support column extending vertically upward from the base body. The outer diameter of the support column is larger than the inner diameter of the cylinder. The first rotating shaft is disposed at the top of the support column and is coaxial with the support column. The main oscillator includes: A lower counterweight, wherein the top center of the lower counterweight is recessed downward to form the mounting cavity, and the first straight hole extends from the mounting cavity to the bottom end of the lower counterweight; and, The upper counterweight covers the top of the lower counterweight and is detachably connected to the upper counterweight.

5. The vibration energy harvester according to claim 4, characterized in that, Both the lower counterweight and the upper counterweight are constructed as vertical cylinders coaxial with the first rotating shaft.

6. The vibration energy harvester according to any one of claims 1 to 5, characterized in that, The energy harvesting component includes a coil disposed on the base and a magnet disposed on the main oscillator; One side of the coil is close to the magnet, and the other side is far from the magnet, so that the magnetic field strength of the coil is different on opposite sides.

7. The vibration energy harvester according to claim 6, characterized in that, The magnet is provided in two parts, which are spaced apart, and the ends of the two magnets that are close to each other are provided with opposite magnetic poles; Two coils are provided, with one side of each coil connected to the base and the other side of each coil disposed between the two magnets. The two coils are connected in series so that the induced electromotive forces generated by the two coils are superimposed in the same direction.

8. The vibration energy harvester according to any one of claims 1 to 5, characterized in that, The energy harvesting assembly includes a piezoelectric ceramic sandwiched between the main oscillator and the base; and / or The power conversion component includes an ultrasonic motor powered by the energy harvesting component.

9. The vibration energy harvester according to claim 1, characterized in that, The speed transmission component includes: An internal gear ring is connected to the top of the main oscillator and is coaxially arranged with the first rotating shaft; The central gear is disposed within the internal gear ring and is coaxially arranged with the internal gear ring; Multiple planetary gears are disposed between the internal gear ring and the central gear, and mesh with the internal gear ring and the central gear; A planetary carrier is disposed on the side of the planetary gears near the main oscillator and is rotatably connected to each of the planetary gears; The second rotating shaft is coaxially arranged with the first rotating shaft, and its two ends are respectively connected to the planetary carrier and the first elastic element; The third rotating shaft is coaxially arranged with the central gear, with one end connected to the central gear and the other end connected to the power conversion component.

10. The vibration energy harvester according to claim 9, characterized in that, The transmission assembly also includes a cover plate that covers the end of the internal gear ring facing away from the main oscillator. A rotating component includes a turntable rotatably connected to the housing, the turntable being rotatable about the axis of the third rotating shaft; A friction plate abuts against the end of the turntable near the cover plate; and The second elastic element, with its two ends connected to the friction plate and the cover plate respectively, is configured to undergo both elastic deformation and torsional elastic deformation in the axial direction of the third rotating shaft. The cover plate is provided with a first through hole, the friction plate is provided with a second through hole, and the third rotating shaft passes through the first through hole and the second through hole and is connected to the turntable.

11. The vibration energy harvester according to claim 10, characterized in that, The second elastic element includes: A first ring is connected to the cover plate, and the third rotating shaft passes through the first ring; Multiple spring bars are evenly distributed in the circumferential direction of the third rotating shaft; In this embodiment, multiple spring bars extend spirally from the first annulus to the friction plate, and the spiral directions are the same.

12. The vibration energy harvester according to claim 10, characterized in that, The rotating component also includes a positioning plate disposed on the side of the turntable facing away from the friction plate and a connecting part connecting the positioning plate and the turntable, wherein the positioning plate is coaxially disposed with the turntable; The card slot is provided on the side of the card slot facing away from the turntable, and the card slot is eccentrically set on the card slot. Top plate, connected to the annular base; and, The blocking component includes a column connected at one end to the top plate and a plurality of blocking plates that are elastically connected to the column. The plurality of blocking plates are arranged in a ring above the movement trajectory of the card slot. A plurality of secondary vibrators extend from the ring base to the side of the blocking plates facing away from the card slot plate. The blocking plates are configured such that they can only be struck by the secondary vibrator to the extent that they can be deflected into the card slot when the corresponding secondary vibrator resonates. When the card slot rotates to the position directly below any blocking plate, the first elastic element rotates to the position where the eigenfrequency of the main vibrator is equal to the eigenfrequency of the secondary vibrator corresponding to the blocking plate.

13. The vibration energy harvester according to claim 12, characterized in that, The secondary oscillator includes a first oscillator elastically connected to the annular base and a second oscillator elastically connected to the first oscillator; The first oscillator and the second oscillator have the same eigenfrequency, the mass of the first oscillator is greater than the mass of the second oscillator, and the second oscillator strikes the blocking plate when resonance occurs.

14. The vibration energy harvester according to claim 12, characterized in that, The surface of the blocking plate facing the sub-oscillator is provided with a buffer membrane.

15. The vibration energy harvester according to claim 6, characterized in that, The electromagnetic damping of the main oscillator is 100 N•s / m.

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