Piezoelectric vibration energy collector based on spring sliding block structure

Abstract

The invention belongs to the technical field of power generation, and particularly relates to a piezoelectric vibration energy collector based on a spring sliding block structure, the piezoelectric vibration energy collector comprises a base assembly, a spring sliding block assembly and a piezoelectric film, the spring sliding block assembly comprises a cantilever beam, the cantilever beam is fixed on the base assembly, a sliding block is arranged on the cantilever beam in a sliding mode, and the piezoelectric film is fixed on the sliding block. Two springs are symmetrically arranged on the two sides of the sliding block, one end of each spring is fixedly connected with the sliding block, the other end of each spring is fixedly connected with the base assembly, and the piezoelectric film is arranged on the lower surface of the cantilever beam. The excitation frequency within a certain range near the resonant frequency can be tracked through the spring sliding block assembly, in the tracking process, the sliding block slides on the cantilever beam in a reciprocating mode, then large-amplitude vibration of the cantilever beam is caused, large electric output of the piezoelectric film is caused, and the piezoelectric effect is achieved. Therefore, the device has the characteristics of high energy collection and output capability and wide working frequency band.

Description

Technical Field

[0001] The invention belongs to the technical field of power generation, and in particular relates to a piezoelectric vibration energy collector based on a spring slider structure. Background Art

[0002] With the rapid development of the Internet of Things (IoT), wireless sensors have been widely used in various fields such as environmental monitoring, smart city construction, and healthcare. However, as time goes by, the power supply problem of sensors has become increasingly prominent. Traditional chemical batteries have many limitations as sensor power sources due to their limited lifespan and high replacement costs.

[0003] The environment contains abundant vibration energy, which is considered to be a promising energy source because it is less affected by climate. Compared with chemical batteries, the collection of vibration energy is not only low-cost, but also almost maintenance-free. Among various energy harvesting technologies based on electromechanical effects such as piezoelectricity, electrostatics, and electromagnetics, piezoelectric energy harvesters have become a more popular choice due to their high energy density, simple structure, and easy integration with microelectronic products.

[0004] Piezoelectric energy harvesting technology relies on the positive piezoelectric effect of piezoelectric materials. When an external mechanical force is applied to a piezoelectric material in a specific direction, the internal lattice structure of the material will deform accordingly, causing electrical polarization. In this process, the two opposite surfaces of the piezoelectric material will generate bound charges of equal amount but opposite sign, and the surface charge density is proportional to the strength of the externally applied mechanical force. When the direction of the external mechanical force changes, the polarity of the bound charge will also be reversed accordingly. This separation of charges forms a potential difference, i.e., voltage, at both ends of the material, thereby realizing the effective conversion and capture of mechanical vibration energy into electrical energy. Based on this mechanism, piezoelectric materials can directly convert mechanical vibration energy in the environment into usable electrical energy.

[0005] Currently, most piezoelectric vibration energy harvesters have a narrow operating frequency band, with a large voltage output at their resonant frequency, and their output voltage drops sharply away from the resonant frequency; in order to widen the operating frequency band, the structure of existing harvesters is designed to be relatively complex, making them difficult to apply in actual situations. Summary of the invention

[0006] In view of the above problems, the present invention provides a piezoelectric vibration energy collector based on a spring slider structure.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A piezoelectric vibration energy collector based on a spring slider structure includes a base assembly, a spring slider assembly and a piezoelectric film, wherein the spring slider assembly includes a cantilever beam, the cantilever beam is fixed on the base assembly, a slider is slidably arranged on the cantilever beam, two springs are symmetrically arranged on both sides of the slider, one end of the spring is fixedly connected to the slider, and the other end of the spring is fixedly connected to the base assembly, and the piezoelectric film is arranged on the lower surface of the cantilever beam.

[0009] Furthermore, the base assembly includes a U-shaped seat and an L-shaped seat, the L-shaped seat is fixedly connected to the U-shaped seat by bolts, and the cantilever beam is clamped and fixed between the U-shaped seat and the L-shaped seat.

[0010] Furthermore, two fixing blocks corresponding to the springs are fixedly arranged on the outer side surface of the U-shaped seat, and the springs are fixedly connected to the fixing blocks.

[0011] Furthermore, the cantilever beam has a thickness of 0.4-0.8 mm and a width of 10-15 mm.

[0012] Furthermore, the height of the rectangular hole on the slider corresponding to the cantilever beam is greater than the thickness of the cantilever beam by 0.1-0.2 mm, and the width of the rectangular hole is greater than the width of the cantilever beam by 0.1-0.2 mm.

[0013] Furthermore, the distance between the side edge of the piezoelectric film close to the base assembly and the U-shaped seat is 5-10 mm.

[0014] Furthermore, the central axis of the piezoelectric film, the central axis of the slider and the central axis of the cantilever beam are all located in the same vertical plane.

[0015] Furthermore, the spring is arranged parallel to the cantilever beam.

[0016] Compared with the prior art, the present invention has the following advantages:

[0017] The present invention can track the excitation frequency within a certain range near the resonant frequency through the spring slider assembly. During the tracking process, the slider will slide back and forth on the cantilever beam, thereby causing the cantilever beam to vibrate significantly, causing a large electrical output of the piezoelectric film, so that the present invention has the characteristics of high energy collection output capacity and wide operating frequency band.

[0018] The invention improves the cantilever beam by combining a spring and a slider, and has the characteristic of simple structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a structural schematic diagram of the present invention;

[0020] Figure 2 A bottom view of the present invention;

[0021] In the figure, there are piezoelectric film 1, cantilever beam 2, slider 3, spring 4, U-shaped seat 5, L-shaped seat 6, and fixed block 7. DETAILED DESCRIPTION

[0022] In order to further illustrate the technical solution of the present invention, the present invention is further described below through embodiments.

[0023] like Figure 1 and Figure 2 As shown, a piezoelectric vibration energy collector based on a spring slider structure includes a base assembly, a spring slider assembly and a piezoelectric film 1, wherein the base assembly includes a U-shaped seat 5 and an L-shaped seat 6, wherein the L-shaped seat 6 is fixedly connected to the U-shaped seat 5 by bolts, and the spring slider assembly includes a cantilever beam 2, wherein the thickness of the cantilever beam 2 is 0.4-0.8 mm and the width is 10-15 mm, wherein the cantilever beam 2 is clamped and fixed between the U-shaped seat 5 and the L-shaped seat 6, and a slider 3 is slidably arranged on the cantilever beam 2, wherein the height of the rectangular hole on the slider 3 corresponding to the cantilever beam 2 is greater than the thickness of the cantilever beam 2 by 0.1-0.2 mm, and the width of the rectangular hole is greater than the thickness of the cantilever beam 2 by 0.1-0.2 mm, and the width of the rectangular hole is greater than the thickness of the cantilever beam 2 by 0.1-0.2 mm. The width of the cantilever beam 2 is 0.1-0.2mm, two springs 4 are symmetrically arranged on both sides of the slider 3, one end of the spring 4 is fixedly connected to the slider 3, and two fixed blocks 7 corresponding to the springs 4 are fixedly arranged on the outer side of the U-shaped seat 5, and the other end of the spring 4 is fixedly connected to the fixed block 7. The spring 4 is arranged parallel to the cantilever beam 2, and the piezoelectric film 1 is arranged on the lower surface of the cantilever beam 2. The distance between the side of the piezoelectric film 1 close to the base assembly and the U-shaped seat 5 is 5-10mm, and the central axis of the piezoelectric film 1, the central axis of the slider 3 and the central axis of the cantilever beam 2 are all located in the same vertical plane.

[0024] The working process of the present invention is as follows: when the excitation frequency of the external environmental vibration to which the U-shaped seat 5 is subjected is not within the frequency range in which the spring slider assembly can track the excitation frequency by itself, the slider 3 does not slide, the cantilever beam 2 vibrates slightly, and the output voltage of the piezoelectric film 1 is low; when the excitation frequency is within the frequency range in which the spring slider assembly can track the excitation frequency by itself, the slider 3 slides periodically, causing the resonant frequency of the cantilever beam 2 to change continuously. When the slider 3 slides toward the free end of the cantilever beam 2, the amplitude of the cantilever beam 2 increases; when the slider 3 slides toward the fixed end of the cantilever beam 2, the amplitude of the cantilever beam 2 decreases. The sliding of the slider 3 causes the resonant frequency of the cantilever beam 2 to change around the excitation frequency. Therefore, the movement of the cantilever beam 2 is multi-periodic, and the output voltage generated by the strain on the piezoelectric film 1 also changes in multiple periods.

[0025] The present invention can make the cantilever beam 2 generate multi-cycle large-scale vibration under the sliding of the slider 3; changing the length of the spring 4 can change the frequency range of the tracking excitation frequency, and changing the mass of the slider 3 can also change the frequency range of the tracking excitation frequency. The present invention discloses energy collection characteristics with a wide operating frequency band and structural characteristics with a simple structure.

[0026] The above shows and describes the main features and advantages of the present invention. It is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive. The scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes that fall within the meaning and scope of the equivalent elements of the claims are included in the present invention.

[0027] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A piezoelectric vibration energy harvester based on a spring slider structure, characterized in that: The invention comprises a base assembly, a spring slider assembly and a piezoelectric film (1), wherein the spring slider assembly comprises a cantilever beam (2), the cantilever beam (2) is fixed on the base assembly, a slider (3) is slidably arranged on the cantilever beam (2), two springs (4) are symmetrically arranged on both sides of the slider (3), one end of the spring (4) is fixedly connected to the slider (3), and the other end of the spring (4) is fixedly connected to the base assembly, and the piezoelectric film (1) is arranged on the lower surface of the cantilever beam (2).

2. The piezoelectric vibration energy collector based on a spring slider structure according to claim 1 is characterized in that: The base assembly comprises a U-shaped seat (5) and an L-shaped seat (6); the L-shaped seat (6) is fixedly connected to the U-shaped seat (5) by bolts; and the cantilever beam (2) is clamped and fixed between the U-shaped seat (5) and the L-shaped seat (6).

3. The piezoelectric vibration energy collector based on a spring slider structure according to claim 2 is characterized in that: Two fixing blocks (7) corresponding one to one with the springs (4) are fixedly arranged on the outer side surface of the U-shaped seat (5), and the springs (4) are fixedly connected to the fixing blocks (7).

4. The piezoelectric vibration energy collector based on a spring slider structure according to claim 1 is characterized in that: The cantilever beam (2) has a thickness of 0.4-0.8 mm and a width of 10-15 mm.

5. The piezoelectric vibration energy collector based on a spring slider structure according to claim 1 is characterized in that: The height of the rectangular hole on the slider (3) corresponding to the cantilever beam (2) is greater than the thickness of the cantilever beam (2) by 0.1-0.2 mm, and the width of the rectangular hole is greater than the width of the cantilever beam (2) by 0.1-0.2 mm.

6. The piezoelectric vibration energy collector based on a spring slider structure according to claim 2 is characterized in that: The distance between the side edge of the piezoelectric film (1) close to the base assembly and the U-shaped seat (5) is 5-10 mm.

7. The piezoelectric vibration energy harvester based on a spring slider structure according to claim 1, characterized in that: The central axis of the piezoelectric film (1), the central axis of the slider (3) and the central axis of the cantilever beam (2) are all located in the same vertical plane.

8. The piezoelectric vibration energy harvester based on a spring slider structure according to claim 1, characterized in that: The spring (4) is arranged parallel to the cantilever beam (2).

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