CN108448937A - A double-track circular arc piezoelectric energy harvester - Google Patents

Abstract

The present invention discloses a double-track arc type piezoelectric energy harvester. The energy harvester includes a pair of cantilever beams. The pair of cantilever beams is formed by connecting two mutually symmetrical cantilever beams. Each cantilever beam consists of a The arc-shaped sheet is connected with a square sheet, the piezoelectric layer is attached to the arc-shaped sheet, and the mass block is attached to the square sheet; the cantilever beam pairs are symmetrically distributed around the diagonal of the square sheet; the circular arc The left end of the type sheet is connected with a square sheet, and the right end of the arc-shaped sheet is a fixed end. The double-track arc-type piezoelectric energy harvester of this technical solution can not only absorb the vibration energy in the direction of the top surface and the side surface, but also has the advantages of high output voltage, high space utilization rate and good stability, and has the advantages of easy integration and miniaturization specialty.

Description

A double-track circular arc piezoelectric energy harvester

technical field

The invention relates to a double-track arc type piezoelectric energy harvester, which belongs to the technical field of energy collection.

Background technique

The piezoelectric energy harvester uses the piezoelectric effect to convert the mechanical energy that cannot be directly used in the surrounding environment into electrical energy that can be directly used. At present, the commonly used piezoelectric energy harvesters are usually straight structures. Although they can play the role of energy harvesting under this structure, experiments have shown that the frequency range of the energy that can be collected is small, and the output potential is low. In addition, piezoelectric energy harvesters with straight structures have a series of defects such as low stability and low space utilization. The traditional single-arc piezoelectric energy harvester is applied to the top or side of the mass block through external vibration, the cantilever beam vibrates and deforms, and the piezoelectric layer generates an electric potential.

Although the traditional high-performance arc-type piezoelectric energy harvester can convert the load into electric energy output under a certain arc, its output potential is significantly smaller under a certain external load, and the energy and space utilization are low, and Structural asymmetry tends to cause stability problems.

Contents of the invention

The purpose of the present invention is to solve the above-mentioned problems existing in the prior art, and to propose a double-track arc type piezoelectric energy harvester.

The purpose of the present invention will be achieved through the following technical solutions: a double-track arc-type piezoelectric energy harvester, comprising a pair of cantilever beams, the pair of cantilever beams is connected by two mutually symmetrical cantilever beams, each The cantilever beams are formed by connecting an arc-shaped sheet and a square sheet, the arc-shaped sheet is attached with a piezoelectric layer, and the square sheet is attached with a mass block.

Preferably, the pairs of cantilever beams are symmetrically distributed around the diagonal of the square sheet.

Preferably, a square sheet is connected to the left end of the arc-shaped sheet, and the right end of the arc-shaped sheet is a fixed end.

Preferably, the square sheet is an arc-shaped material layer.

Preferably, the cantilever beam is made of phosphor bronze.

Preferably, the arc-shaped sheet has an inner diameter of 20 mm, an outer diameter of 30 mm, a width of 10 mm, and an arc of 90 degrees.

Preferably, the piezoelectric layer is PZT-5H.

Preferably, the inner diameter of the piezoelectric layer is 20 mm, the outer diameter is 30 mm, the thickness is 0.3 mm, and the arc is 90 degrees.

Preferably, the mass block is made of nickel material.

Preferably, the length, width and height of the proof mass are 10mm, 10mm and 10mm respectively.

The advantage of technical solution of the present invention is mainly reflected in:

Under the condition that the external excitation load remains unchanged, the piezoelectric layer area of the double-rail arc piezoelectric energy harvester is twice that of the arc-shaped piezoelectric energy harvester, which means that the double-rail piezoelectric energy harvester can Energy that puts out more power and therefore has a higher potential.

For a mass block of the same size, the double-track arc-type piezoelectric energy harvester corresponds to two piezoelectric layers, while the arc-type piezoelectric energy harvester has a single-track structure, and only one piezoelectric layer corresponds to the mass block. This structure can effectively improve the space utilization rate, and further improve the integration degree of the device as an integrated unit small module of a piezoelectric integrated chip.

The double-track arc-type piezoelectric energy harvester is composed of two completely symmetrical cantilever beams and the piezoelectric layer attached to it, so it has symmetry, which makes the double-track piezoelectric energy harvester have better symmetry and applicability. Compared with the single-track arc-type piezoelectric energy harvester, the double-track arc-type piezoelectric energy harvester of this technical solution can not only absorb the vibration energy in the top and side directions, but also has high output voltage and high space utilization , good stability, and has the characteristics of easy integration and miniaturization.

Description of drawings

FIG. 1 is a schematic structural view of a double-track arc-type piezoelectric energy harvester of the present invention.

FIG. 2 is a graph showing the relationship between the output voltage and frequency of the arc-type piezoelectric energy harvester and the double-track arc-type piezoelectric energy harvester of the present invention.

Detailed ways

Objects, advantages and features of the present invention will be illustrated and explained by the following non-limiting description of preferred embodiments. These embodiments are only typical examples of applying the technical solutions of the present invention, and all technical solutions formed by adopting equivalent replacements or equivalent transformations fall within the protection scope of the present invention.

The present invention discloses a double-track arc type piezoelectric energy harvester, as shown in Figure 1, a double-track arc type piezoelectric energy harvester includes a cantilever beam pair 1, and the cantilever beam pair consists of two Two mutually symmetrical cantilever beams are symmetrically connected, and each said cantilever beam is formed by symmetrically connecting an arc-shaped sheet 2 and a square sheet 3, specifically, each said cantilever beam is composed of two identical cantilever beams. It is formed by connecting arc-shaped thin slices with a certain radian and square thin slices. The cantilever beam is made of phosphor bronze material with wide sources, good ductility and easy deformation.

A piezoelectric layer 4 is attached to the arc-shaped sheet, and a mass block 5 is attached to the square sheet. The piezoelectric layer is PZT-5H. The inner diameter of the piezoelectric layer is 20 mm, the outer diameter is 30 mm, the thickness is 0.3 mm, and the arc is 90 degrees, and the arc-shaped piezoelectric layer of 90 degrees is attached to the arc-shaped sheet of 90 degrees. The mass block is made of high-density nickel material, and the mass block is attached to a square sheet. The length, width, and height of the mass block are 10 mm, 10 mm, and 10 mm, respectively. For the double-track arc-shaped piezoelectric energy harvesters with different radians, the arc-shaped slices corresponding to the cantilever beam have different radians from the piezoelectric layer to which they are attached.

The left end of the arc-shaped sheet is connected with a square sheet, the length and width of the square sheet are LM=10mm, WM=10mm, the width of the base layer is W=10mm, and the thickness HS=0.5mm. The right end is the fixed end 6. The arc-shaped sheet has an inner diameter Ra of 20 mm, an outer diameter Rb of 30 mm, a width of 10 mm, and an arc of 90 degrees.

The two pairs of identical cantilever beams are symmetrically distributed around the diagonal line of the square sheet, which makes the double-rail piezoelectric energy harvester have better stability. The two piezoelectric layers are connected to the same mass block, which enables the double-track arc-type piezoelectric energy harvester to output higher power energy under the condition that the external excitation load remains unchanged. In addition, the double-rail structure effectively improves the space utilization rate of the piezoelectric energy harvester of the present invention, and further improves the integration degree of the technical solution as an integrated unit small module of the piezoelectric integrated chip.

In order to better reflect the advantages of this structure compared to arc-type piezoelectric energy harvesters, a boundary load of 10 Pa vertically downward is applied to the top of the mass block to make arc-type and double-track arc-type piezoelectric energy harvesters. The relationship diagram between the output voltage of the device and the energy frequency is shown in Figure 2. In Figure 2, the abscissa represents the power, and the ordinate represents the voltage. It can be found from the figure that for the arc-type piezoelectric energy harvester, the first-order resonance frequency is 85Hz, and the output voltage at this time is 0.69V. For the relationship between voltage and frequency of the double-rail arc-type piezoelectric energy harvester, when the first-order frequency is 90Hz, the energy harvester has the highest output voltage of 0.94V. It can be seen that, compared with the arc-shaped piezoelectric energy harvester, the double-track arc-type energy harvester has a better output high potential advantage.

Combining with Figure 1, it can be found that for the same size mass, the double-rail arc-type piezoelectric energy harvester of this technical solution corresponds to two piezoelectric layers, while the arc-type piezoelectric energy harvester has a single-rail structure, only A piezoelectric layer corresponds to the proof mass. This structure effectively improves the space utilization rate, and further improves the integration degree of the small integrated unit module of the piezoelectric integrated chip of the present invention.

The double-track circular-arc piezoelectric energy harvester of the technical solution is composed of two completely symmetrical cantilever beams and piezoelectric layers attached to them, so it has symmetry. This makes the double-rail piezoelectric energy harvester also have better symmetry. Compared with the single-track arc-type piezoelectric energy harvester, the double-track arc-type piezoelectric energy harvester of this technical solution can not only absorb the vibration energy in the top and side directions, but also has high output voltage and high space utilization , good stability, and has the characteristics of easy integration and miniaturization.

Compared with the traditional arc-shaped piezoelectric energy harvester, the energy harvester adopts a certain arc-shaped double-track arc-shaped symmetrical structure design. When the excitation acts on the mass block, the specific arc-shaped piezoelectric energy harvester can generate a higher electric potential. At the same time, the double-track arc-shaped energy harvester can not only improve the space utilization rate of the device, improve the integration degree, but also enhance the stability, and has high research value.

In summary, the energy harvester of the present invention adopts a double-track circular arc structure design with a symmetrical structure. When the excitation acts on the mass, the arc-shaped piezoelectric energy harvester of a specific arc generates a higher electric potential. In addition to being able to output ultra-high potential, the double-track arc-shaped energy harvester can also improve space utilization and device integration, and bring better stability.

There are still many implementations in the present invention, and all technical solutions formed by equivalent transformation or equivalent transformation fall within the protection scope of the present invention.

Claims (10)

1. A double-track arc-type piezoelectric energy harvester is characterized in that: it comprises a cantilever beam pair, and the cantilever beam pair is formed by two mutually symmetrical cantilever beams being connected symmetrically, each of the cantilever beams being It is formed by connecting an arc-shaped thin slice and a square thin slice, a piezoelectric layer is attached to the arc-shaped thin slice, and a quality block is attached to the square thin slice. 2 . The dual-track arc-type piezoelectric energy harvester according to claim 1 , wherein the cantilever beam pairs are symmetrically distributed around the diagonal line of the square sheet. 3 . 3. A double-track arc-shaped piezoelectric energy harvester according to claim 1, wherein a square sheet is connected to the left end of the arc-shaped sheet, and the right end of the arc-shaped sheet is a fixed end . 4 . The dual-track arc-shaped piezoelectric energy harvester according to claim 1 , wherein the square sheet is an arc-shaped material layer. 5 . The dual-rail arc piezoelectric energy harvester according to claim 1 , wherein the cantilever beam is made of phosphor bronze. 5 . 6. A kind of dual-track arc-type piezoelectric energy harvester according to claim 1, characterized in that: the inner diameter of the arc-shaped sheet is 20mm, the outer diameter is 30mm, the width is 10mm, and the arc degree is 90 degrees. 7. A double-track arc type piezoelectric energy harvester according to claim 1, characterized in that: the piezoelectric layer is PZT-5H. 8. A kind of dual-track arc type piezoelectric energy harvester according to claim 1, characterized in that: the inner diameter of the piezoelectric layer is 20mm, the outer diameter is 30mm, the thickness is 0.3mm, and the arc degree is 90 degrees. 9. A double-track arc-type piezoelectric energy harvester according to claim 1, wherein the mass block is made of nickel material. 10 . The double-track circular arc piezoelectric energy harvester according to claim 1 , wherein the length, width and height of the mass block are 10 mm, 10 mm and 10 mm, respectively. 11 .