CN214177185U

CN214177185U - Nonlinear two-degree-of-freedom multi-resonance piezoelectric energy collector

Info

Publication number: CN214177185U
Application number: CN202023142263.6U
Authority: CN
Inventors: 申俊; 宋芳; 史晓帆; 张帆
Original assignee: Shanghai University of Engineering Science
Current assignee: Shanghai University of Engineering Science
Priority date: 2020-12-21
Filing date: 2020-12-21
Publication date: 2021-09-10
Anticipated expiration: 2030-12-21

Abstract

The utility model relates to a two non-linear degree of freedom multi-resonance piezoelectric energy collectors, including the outside support, set up power transmission part on the outside support and be fixed in adjustable hold assembly and the piezoelectricity collection part in the outside support through elastic element flexonics. Compared with the prior art, the utility model discloses a cantilever beam structure of the two degree of freedom of nonlinearity of piezoelectricity collection part can make the resonant frequency of cantilever beam match with external excitation source, and power transmission part can convert the low frequency of external excitation source into the high-frequency vibration of piezoelectricity collection part simultaneously, can adjust the position of placing of piezoelectricity collection part through adjustable hold assembly, makes the vibration frequency that piezoelectricity collection part can self-adaptation match external excitation source.

Description

Nonlinear two-degree-of-freedom multi-resonance piezoelectric energy collector

Technical Field

The utility model belongs to the technical field of new forms of energy and electricity generation, a little energy collection technique is related to, especially, relate to a two non-linear degrees of freedom multi-resonance piezoelectric energy collector.

Background

With the rapid development of wireless technology and micro-electro-mechanical systems (MEMS) technology, microelectronic devices are applied in various fields, and their application environments are becoming more and more complex. In the face of such circumstances, how to supply power to microelectronic devices becomes an urgent problem to be solved. The traditional battery power supply has a plurality of limitations on the application of the power supply of a microelectronic system due to a series of problems of short service life, limited stored energy, environmental pollution after being scrapped and the like.

Vibrational energy is a ubiquitous form of energy in the environment, from a wide variety of sources, including various industrial mechanical vibrations, as well as naturally occurring vibrations, such as wind-induced vibrations in nature. The collection of vibration energy is mainly through mechanical vibration in the environment converting into electrical energy and storing it through an energy collection circuit. The following three methods can be roughly classified according to the principle of acquisition: electrostatic, electromagnetic, piezoelectric, and magnetostrictive. The piezoelectric energy collection technology has the advantages of high electromechanical conversion efficiency, no need of a driving power supply and output voltage, and high energy density; meanwhile, the piezoelectric energy collector has a compact structure and strong environmental adaptability, and is easy for MEMS technology integration, so that the piezoelectric energy collection technology is favored.

The mechanism of the piezoelectric energy collection technology is that the piezoelectric effect based on the piezoelectric material converts the vibration energy into electric energy. When the external force action direction is changed, the polarity of the charges is changed, and therefore mechanical vibration energy is converted into electric energy.

At present, a piezoelectric energy collector often has a large voltage output only at a resonant frequency, the output voltage of the piezoelectric energy collector is rapidly reduced when the resonant frequency deviates from the resonant frequency, and the piezoelectric energy collector has the defects of low energy conversion efficiency, narrow working frequency band and the like. The working range of the piezoelectric energy collector is limited, and the practicability is not strong.

SUMMERY OF THE UTILITY MODEL

The utility model discloses based on nonlinear technical principle, a nonlinear two degree of freedom multivibration piezoelectric energy collector with broadband is provided. Through the nonlinear two-degree-of-freedom cantilever beam structure of the piezoelectric acquisition component, the resonant frequency of the cantilever beam can be matched with an external excitation source, meanwhile, the power transmission component can convert the low frequency of the external excitation source into the high-frequency vibration of the piezoelectric acquisition component, the placement position of the piezoelectric acquisition component can be adjusted through the adjustable clamping component, and the piezoelectric acquisition component can be matched with the vibration frequency of the external excitation source in a self-adaptive manner.

The purpose of the utility model can be realized through the following technical scheme:

a nonlinear two-degree-of-freedom multi-resonance piezoelectric energy collector comprises an external support, a power transmission part flexibly connected and arranged on the external support through an elastic element, and an adjustable clamping part and a piezoelectric collecting part which are fixed in the external support;

the piezoelectric acquisition component comprises a two-degree-of-freedom cantilever beam mechanism, a stress plate, two moving plates and two stress springs; the two-degree-of-freedom cantilever beam mechanism is provided with a fixed plate clamped by an adjustable clamping part, two cantilever beams which extend out from one side of the fixed plate and are arranged in parallel, a piezoelectric piece attached to each cantilever beam and a cantilever beam permanent magnet arranged at the tail end of each cantilever beam; the two movable plates are slidably arranged on the fixed plate in a penetrating mode and are respectively positioned on the upper side and the lower side of the cantilever beams arranged in parallel, the first ends of the two movable plates are positioned on one side of the cantilever beam of the fixed plate and are provided with movable plate permanent magnets, the second ends of the two movable plates are fixedly connected with the stress plate, and the two stress springs are respectively sleeved on the movable plate between the stress plate and the fixed plate;

the power transmission component is used for applying force to the stress plate in the rotating process so as to enable the stress plate to move along the axial direction of the stress spring.

Preferably, the part of the moving plate on the cantilever beam side of the fixed plate and the cantilever beam are both in a strip plate shape and are horizontally arranged in a natural state.

Preferably, the moving plate permanent magnets on the two moving plates are mutually attracted with the cantilever beam permanent magnets on the cantilever beams arranged in parallel, and the moving plate permanent magnets on the two moving plates are mutually attracted.

Preferably, the part of the moving plate penetrating through the fixed plate is cylindrical.

Preferably, the power transmission part include the rotor plate, the rotor plate bear on the outside support through elastic element, and the rotor plate is equipped with the L type towards the atress board towards one side in the outside support and hits the piece, L type hit the piece and be used for exerting force in the atress board when the rotor plate takes place to rotate, make the atress board along the motion of atress spring axis direction.

Preferably, the power transmission part further comprises a rotating shaft which is arranged on the rotating plate in a penetrating mode and fixed on the rotating plate, torsion spring coil fixing seats which are fixedly arranged and are respectively and rotatably connected with two ends of the rotating shaft, and torsion spring coils which are connected between the rotating shaft and the torsion spring coil fixing seats.

Preferably, the axis of rotation be both ends fluting axis of rotation, torsional spring coil fixing base on be equipped with the notch, the both ends of torsional spring coil block respectively in the notch of axis of rotation tip and the notch of torsional spring coil fixing base.

Preferably, the adjustable clamping component comprises a parallel motion guide base, a double-rotation-direction screw arranged in the middle of the motion guide base through a screw supporting base, a first nut seat and a second nut seat which are connected with the motion guide base in a sliding mode and respectively arranged on two sections of threads with different rotation directions of the double-rotation-direction screw, a friction plate arranged on the inner side surfaces of the first nut seat and the second nut seat, and screw knobs arranged at two ends of the double-rotation-direction screw.

Preferably, the adjustable clamping member is mounted inside the outer bracket via a base.

Preferably, the outer bracket is provided with a blocking plate, and the power transmission part is flexibly connected and arranged on the blocking plate through an elastic element.

The utility model discloses in: the outer support is primarily used to support the power transmission component. The base is used for fixing the adjustable clamping component. The power transmission member is mainly used to transmit an external excitation source. The piezoelectric acquisition component is used for converting vibration energy transmitted from the outside into electric energy. The adjustable clamping component is used for adjusting the position where the piezoelectric acquisition component is placed, and the energy acquisition efficiency is improved. The blocking plate serves to restrict excessive rotation of the power transmission member. The elastic element is used for connecting the power component and the blocking plate and accumulating elastic potential energy.

In the utility model, the rotating plate of the power transmission part compresses the elastic element (preferably a compression spring) under the action of external excitation, so that the elastic element accumulates elastic potential energy, and further preferably, the rotating plate drives the rotating shaft to deflect, so that the elastic potential energy can be accumulated in the torsion spring coil; corresponding to the conversion of the external excitation into the elastic potential energy of the elastic components (compression spring and torsion spring coil). After the external excitation disappears, the rotating plate does simple harmonic motion due to the release of the elastic potential energy. The rotation angle of the rotating plate is preferably smaller than 90 degrees, and the L-shaped striking block on the rotating plate strikes the piezoelectric acquisition component due to the reciprocating deflection of the rotating plate, so that the piezoelectric acquisition module is continuously excited. The piezoelectric acquisition component is continuously hit by the L-shaped hitting block, self-resonance is generated by the piezoelectric acquisition component, and the vibration energy is converted into electric energy.

The utility model discloses a multi-resonance is the resonance frequency bandwidth of two degree of freedom structures of nonlinearity, and piezoelectricity collection part has a plurality of resonant frequency. The utility model discloses a non-linearity indicates to add the permanent magnet at the cantilever beam end, and the potential energy function of whole vibration energy collection part has taken place to change after introducing the magnetic field, becomes non-linear potential energy function system, and whole piezoelectricity collection part forms the non-linear vibration. The utility model discloses a two degrees of freedom refer to in the energy harvesting part left and right cantilever beam accept external excitation, and the vibration between the left and right cantilever beam passes through magnetic force and influences each other simultaneously, forms an interact's structural system. The utility model discloses an adjustable clamping part is used for fixed and the height and the transverse position that the position of adjusting piezoelectricity collection part can control piezoelectricity collection part centre gripping.

Compared with the prior art, the utility model discloses following beneficial effect has:

the utility model provides a power transmission module that two non-linear degrees of freedom multivibration piezoelectric energy collectors adopted can turn into elastomeric element's elastic potential energy with the energy of external vibration excitation, and the temporary storage energy is after external vibration excitation disappears, and elastomeric element will drive the rotor plate, is simple harmonic motion together.

The utility model discloses the simple harmonic rotary motion of transfer board makes the L type hit the piece and constantly hit and hit the piezoelectricity collection part to encourage many times that piezoelectricity energy collection part produces the self-resonance, turn into the electric energy with external vibration energy.

The utility model discloses the cantilever beam piezoelectricity collection part of the middle two degree of freedom that adopt non-linearity has the frequency band of broad, can produce great amplitude in the frequency range of broad to produce great stress and meeting an emergency on the piezoelectric chip, improved energy conversion efficiency, increase the output of electric energy.

The utility model discloses with the high-frequency vibration of the input conversion of external low frequency for piezoelectric energy acquisition part cantilever beam, make piezoelectric energy acquisition module receive excitation many times, all improved energy acquisition efficiency, increased electric energy output.

Drawings

Fig. 1 is a schematic structural view of the present invention at a viewing angle.

Fig. 2 is a schematic structural diagram of the present invention at another viewing angle.

Fig. 3 is a schematic view of the adjustable clamping member of the present invention.

Fig. 4 is a schematic structural diagram of the piezoelectric collecting component of the present invention.

Fig. 5 is an explosion diagram of the piezoelectric collecting component of the present invention.

Fig. 6 is a schematic structural view of the power transmission component of the present invention.

In the figure, 1 is an external support, 2 is a piezoelectric collecting component, 21 is a moving plate, 22 is a cantilever permanent magnet, 23 is a piezoelectric plate, 24 is a two-degree-of-freedom cantilever mechanism, 241 is a fixed plate, 242 is a cantilever beam, 25 is a moving plate permanent magnet, 26 is a stressed spring, 27 is a stressed plate, 3 is an adjustable clamping component, 31 is a motion guide base, 32 is a first nut seat, 33 is a double-rotation-direction screw, 34 is a screw knob, 35 is a friction plate, 36 is a screw support seat, 37 is a second nut seat, 4 is a power transmission component, 41 is a rotating plate, 42 is a rotating shaft, 43 is a torsion spring ring fixing seat, 44 is a torsion spring ring, 45 is an L-shaped beating block, 5 is a base, 6 is an elastic element, and 7 is a blocking plate.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

In the description of the present invention, it should be noted. The terms "upper", "lower", "center", "left", "right", "inside/outside", "top/bottom", and the like indicate orientations or positional relationships that are based on the orientations or positional relationships shown in the drawings only for convenience of describing the present invention and simplifying the description, but do not indicate or imply that the device or element referred to must have a particular orientation, be constructed in a particular orientation, and be operated, and therefore should not be construed as limiting the present invention.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "disposed," "placed," "connected," and the like are to be construed broadly, and for example, "connected" may be either fixedly connected or detachably connected, or integrally connected; the two elements may be mechanically connected, welded, directly connected, indirectly connected through an intermediate medium, or communicated with each other. The specific meaning of the above terms in the present application can be understood in a specific case to those skilled in the art.

Example 1

A nonlinear two-degree-of-freedom multi-resonance piezoelectric energy collector is shown in figures 1, 2, 4 and 5 and comprises an external support 1, a power transmission part 4 flexibly connected and arranged on the external support 1 through an elastic element 6, an adjustable clamping part 3 fixed in the external support 1 and a piezoelectric acquisition part 2; the piezoelectric acquisition component 2 comprises a two-degree-of-freedom cantilever beam mechanism 24, a stress plate 27, two moving plates 21 and two stress springs 26; the two-degree-of-freedom cantilever mechanism 24 includes a fixed plate 241 held by the adjustable holding member 3, two cantilevers 242 arranged in parallel and extending from one side of the fixed plate 241, a piezoelectric sheet 23 attached to each cantilever 242 (as shown in fig. 4 and 5, the piezoelectric sheet is attached to the upper surface of the cantilever 242), and a cantilever permanent magnet 22 provided at the end of each cantilever 242; the two moving plates 21 slidably penetrate through the fixed plate 241 and are respectively located at the upper side and the lower side of the cantilever beams 242 arranged in parallel, the first ends of the two moving plates 21 are located at one side of the cantilever beam 242 of the fixed plate 241 and are provided with moving plate permanent magnets 25, the second ends of the two moving plates 21 are fixedly connected with the stress plate 27, and the two stress springs 26 are respectively sleeved on the moving plate 21 between the stress plate 27 and the fixed plate 241; the power transmission member 4 is used for applying force to the force bearing plate 27 during rotation, so that the force bearing plate 27 moves along the axial direction of the force bearing spring 26.

In this embodiment, the portion of the moving plate 21 on the cantilever beam 242 side of the fixed plate 241 and the cantilever beam 242 are preferably both in the shape of a long strip and are horizontally arranged in a natural state. It is further preferable that the portion of the moving plate 21 penetrating the fixing plate 241 is cylindrical, and it is further preferable that the portion of the moving plate 21 on the other side of the fixing plate 242 is cylindrical, forming a cylindrical end, and the forced spring 26 is sleeved on the cylindrical end, as shown in fig. 4 and 5. In the present embodiment, the moving plate 21 is preferably fastened to the force-bearing plate 27 by screws. Further preferably, the moving plate permanent magnets 25 on the two moving plates 21 are attracted to the cantilever beam permanent magnets 22 on the cantilever beams 242 arranged in parallel, and the moving plate permanent magnets 25 on the two moving plates 21 are attracted to each other. For example, in the present embodiment, as shown in fig. 4 and 5, the upper and lower surfaces of the cantilever beam permanent magnet 22 at the end of the cantilever beam 242 are respectively S-level and N-level. The lower surface (the surface facing the 242 surfaces of the two cantilevers) of the permanent magnet 25 of the moving plate at the first end of the upper moving plate 21 is the N-pole, and the upper surface (the surface facing the 242 surfaces of the two cantilevers) of the permanent magnet 25 of the moving plate at the first end of the lower moving plate is the S-pole.

In this embodiment, as shown in fig. 6, preferably, the power transmission component 4 includes a rotating plate 41, the rotating plate 41 is supported on the outer bracket 1 through an elastic element 6, and one side of the rotating plate 41 facing the inside of the outer bracket 1 is provided with an L-shaped striking block 45 pointing to the force-bearing plate 27, and the L-shaped striking block 45 is used for applying force to the force-bearing plate 27 when the rotating plate 41 rotates, so that the force-bearing plate 27 moves along the axial direction of the force-bearing spring 26. Further preferably, the power transmission member 4 further includes a rotating shaft 42 passing through and fixed on the rotating plate 41, a torsion spring coil fixing seat 43 fixedly disposed and rotatably connected to two ends of the rotating shaft 42 respectively (the fixing seat 43 may be fixed on the external bracket 1 or may be fixed on other external equipment), and a torsion spring coil 44 connected between the rotating shaft 42 and the torsion spring coil fixing seat 43. It is further preferable that the rotating shaft 42 is a rotating shaft with notches at two ends, the torsion spring coil fixing seat 43 is provided with notches, and two ends of the torsion spring coil 44 are respectively clamped into the notches at the end of the rotating shaft 42 and the notches of the torsion spring coil fixing seat 43. In this embodiment, as shown in fig. 1, 2 and 6, two blocking plates 7 are preferably disposed at two ends of the outer bracket 1, and four corners of the rotating plate 41 are flexibly connected to the two blocking plates 7 through the elastic member 6. The elastic element 6 is preferably a compression spring.

In the present embodiment, as shown in fig. 3, it is preferable that the adjustable clamping member 3 includes a movement guide base 31 (the movement guide base 31 has two guide rails arranged side by side), a double-handed screw 33 (the double-handed screw 33 is a screw having different-handed threads at both ends thereof, and the axial direction of the double-handed screw 33 is the same as the guiding direction of the movement guide base 31) provided in the middle of the movement guide base 31 through a screw support 36, a first nut seat 32 (a nut seat on the right side in fig. 3) and a second nut seat 37 (a nut seat on the left side in fig. 3) slidably coupled (fitted) to the movement guide base 31 and respectively provided on two different-handed threads of the double-handed screw 33, a friction plate 35 provided on the inner side surfaces of the first nut seat 32 and the second nut seat 37, and screw knobs 34 provided on both ends of the double-handed screw 33. Preferably the adjustable clamping member 3 is mounted inside the outer bracket 1 by means of a base 5. The fixing plate 241 of the piezoelectric pickup unit 2 can be clamped by rotating the screw knob 34.

In this embodiment, the rotating plate 41 is a stressed portion excited by the outside, so that the elastic element 6 (compression spring) and the torsion coil 44 connected to the rotating plate 41 obtain elastic potential energy, and the rotating plate 41 deflects. Meanwhile, the L-shaped striking block 45 fixed to the rotating plate 41 deflects along with the rotating plate 41, so that the L-shaped striking block 45 strikes the piezoelectric pickup unit 2. The stress plate 27 of the piezoelectric acquisition component 2 receives the impact of the L-shaped impact block 45, the stress plate 27 extrudes the stress spring 26 to push the moving plate 21 to move, the moving plate permanent magnet 25 and the cantilever beam permanent magnet 22 at the tail end of the moving plate 21 move to generate excitation, vibration is transmitted to the two-degree-of-freedom cantilever beam 242, and meanwhile, the piezoelectric sheet 23 is subjected to tensile or compressive strain due to the vibration of the two-degree-of-freedom piezoelectric cantilever beam 242. So that there is a charge output on the piezoelectric patch 23. When the external excitation disappears, the elastic element 6 and the torsion spring coil 44 release the elastic potential energy to make the rotating plate 41 generate the reciprocating deflection in the process of restoring the rotating plate 41 to the original position, and perform the simple harmonic motion. The rotating plate 41 is deflected to and fro, so that the L-shaped impact block 45 continuously and continuously impacts the piezoelectric acquisition component 2, and the piezoelectric acquisition component 2 generates self-resonance. By continuously exciting the piezoelectric collecting member 2, the external vibration energy is converted into electric energy. Meanwhile, the screw knob 34 can be rotated by adopting the adjustable clamping part 3, and the position of the piezoelectric acquisition part 2 impacted by the L-shaped impact block 45 is adjusted by opening and closing the second nut seat 37 and the first nut seat 32, so that the piezoelectric acquisition part can be better matched with the frequency of an external vibration excitation source, and the energy conversion efficiency is improved. The utility model discloses become external single excitation into the rotation back and forth of rotor plate 41, the L type is hit 2 that beat piece 45 constantly strike piezoelectricity collection part and is made the low frequency vibration excitation source become the high frequency vibration excitation source, has improved the efficiency to energy acquisition, has increased the output of electric energy.

The embodiments described above are intended to facilitate the understanding and use of the invention by those skilled in the art. It will be readily apparent to those skilled in the art that various modifications to these embodiments may be made, and the generic principles described herein may be applied to other embodiments without the use of the inventive faculty. Therefore, the present invention is not limited to the above embodiments, and those skilled in the art should make improvements and modifications within the scope of the present invention according to the disclosure of the present invention.

Claims

1. A nonlinear two-degree-of-freedom multi-resonance piezoelectric energy collector is characterized by comprising an external support (1), a power transmission part (4) flexibly connected and arranged on the external support (1) through an elastic element (6), and an adjustable clamping part (3) and a piezoelectric collecting part (2) which are fixed in the external support (1);

the piezoelectric acquisition component (2) comprises a two-degree-of-freedom cantilever beam mechanism (24), a stress plate (27), two moving plates (21) and two stress springs (26); the two-degree-of-freedom cantilever beam mechanism (24) is provided with a fixed plate (241) clamped by the adjustable clamping part (3), two cantilever beams (242) which extend out from one side of the fixed plate (241) and are arranged in parallel, a piezoelectric sheet (23) attached to each cantilever beam (242) and a cantilever beam permanent magnet (22) arranged at the tail end of each cantilever beam (242); the two moving plates (21) are slidably arranged on the fixed plate (241) in a penetrating mode and are respectively located on the upper side and the lower side of the cantilever beams (242) which are arranged in parallel, the first ends of the two moving plates (21) are located on one side of the cantilever beams (242) of the fixed plate (241) and are provided with moving plate permanent magnets (25), the second ends of the two moving plates (21) are fixedly connected with the stress plate (27), and the two stress springs (26) are respectively sleeved on the moving plates (21) between the stress plate (27) and the fixed plate (241);

the power transmission component (4) is used for applying force to the stress plate (27) in the rotating process, so that the stress plate (27) moves along the axial direction of the stress spring (26).

2. The non-linear two-degree-of-freedom multi-resonance piezoelectric energy collector according to claim 1, wherein the portion of the moving plate (21) on the cantilever beam (242) side of the fixed plate (241) and the cantilever beam (242) are both in the shape of an elongated plate and are horizontally arranged in a natural state.

3. The non-linear two-degree-of-freedom multi-resonance piezoelectric energy collector according to claim 1 or 2, characterized in that the moving plate permanent magnets (25) on the two moving plates (21) are mutually attracted with the cantilever beam permanent magnets (22) on the cantilever beams (242) arranged in parallel, and the moving plate permanent magnets (25) on the two moving plates (21) are mutually attracted.

4. The non-linear two-degree-of-freedom multi-resonant piezoelectric energy collector as claimed in claim 2, wherein the portion of the moving plate (21) penetrating through the fixed plate (241) is cylindrical.

5. The non-linear two-degree-of-freedom multi-resonance piezoelectric energy collector as claimed in claim 1, wherein the power transmission component (4) comprises a rotating plate (41), the rotating plate (41) is carried on the outer support (1) through an elastic element (6), an L-shaped striking block (45) pointing to the stress plate (27) is arranged on one side of the rotating plate (41) facing the inner side of the outer support (1), and the L-shaped striking block (45) is used for applying force to the stress plate (27) when the rotating plate (41) rotates, so that the stress plate (27) moves along the axial direction of the stress spring (26).

6. The non-linear two-degree-of-freedom multi-resonance piezoelectric energy collector according to claim 5, wherein the power transmission part (4) further comprises a rotating shaft (42) penetrating and fixed on the rotating plate (41), torsion spring coil fixing seats (43) fixedly arranged and rotatably connected with two ends of the rotating shaft (42) respectively, and torsion spring coils (44) connected between the rotating shaft (42) and the torsion spring coil fixing seats (43).

7. The non-linear two-degree-of-freedom multi-resonance piezoelectric energy collector as claimed in claim 6, wherein the rotating shaft (42) is a rotating shaft with notches at two ends, the torsion spring coil fixing seat (43) is provided with notches, and two ends of the torsion spring coil (44) are respectively clamped into the notch at the end part of the rotating shaft (42) and the notch of the torsion spring coil fixing seat (43).

8. The non-linear two-degree-of-freedom multi-resonance piezoelectric energy harvester according to claim 1, wherein the adjustable clamping component (3) comprises a motion guide base (31), a double-rotation screw (33) arranged in the middle of the motion guide base (31) through a screw support seat (36), a first nut seat (32) and a second nut seat (37) which are connected with the motion guide base (31) in a sliding manner and respectively arranged on two sections of threads with different rotation directions of the double-rotation screw (33), friction plates (35) arranged on inner side surfaces of the first nut seat (32) and the second nut seat (37), and screw knobs (34) arranged at two ends of the double-rotation screw (33).

9. The non-linear two-degree-of-freedom multi-resonant piezoelectric energy harvester according to claim 1, characterized in that the adjustable clamping member (3) is mounted inside the outer support (1) by a base (5).

10. The non-linear two-degree-of-freedom multi-resonance piezoelectric energy harvester according to claim 1, wherein the outer support (1) is provided with a blocking plate (7), and the power transmission part (4) is flexibly connected with the blocking plate (7) through an elastic element (6).