Omnidirectional vibration energy collecting device and adjusting method thereof

Abstract

The invention discloses an omni-directional vibration energy collection device and an adjusting method thereof, and belongs to the technical field of energy collectors, and the omni-directional vibration energy collection device comprises a swing mechanism, a base plate, a matching block and four side plates. According to the invention, omnidirectional energy collection can be realized, and the complex structure caused by arraying unidirectional collectors along different directions and the difficulty brought by signal processing are avoided; under the action of the mass block, the supporting slender rod and the matching block, the bending deformation of the piezoelectric plate is greater than the deformation generated by only placing the side plate, and meanwhile, the defect of low torsional deformation voltage signal is avoided; the inherent frequency of the structure can be changed by adjusting the height of the supporting slender rod and the mass of the mass block, resonance with the excitation frequency is achieved, bending deformation of the piezoelectric plate is increased, and therefore piezoelectric voltage output is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of energy harvesters, and in particular to an omnidirectional vibration energy harvesting device and an adjustment method thereof. Background Art

[0002] Most of the existing energy harvesters can only perform unidirectional energy harvesting and cannot be used in multiple scenarios, so their usage scenarios are limited. Some energy harvesters can achieve multi-directional energy harvesting (Kan Junwu, Wu Yaqi, Zhang Zhonghua, et al. Research on torsion pendulum multi-directional piezoelectric vibration energy harvester [J]. China Mechanical Engineering, 2023, 34(4): 440-445. DOI: 10.3969 / j.issn.1004-132X.2023.04.008.), but some directions are distortion deformation of thin plates, and the harvesting efficiency is low. In order to improve the efficiency of low-frequency vibration energy harvesting, some experts and scholars have arranged unidirectional energy harvesters in an array to achieve multi-directional energy harvesting, but this form of structure is relatively complex, which limits the application of energy harvesters in the field of self-powered sensors.

[0003] How to achieve omnidirectional energy harvesting under the condition of reducing structural complexity is an urgent problem to be solved. To this end, the present invention proposes an omnidirectional vibration energy harvesting device and an adjustment method thereof. Summary of the invention

[0004] The technical problem to be solved by the present invention is: how to achieve omnidirectional energy harvesting under the condition of reducing structural complexity, and to provide an omnidirectional vibration energy harvesting device.

[0005] The present invention solves the above technical problems through the following technical solutions. The present invention includes a swing mechanism, a substrate, a matching block and four side plates. The upper end of the swing mechanism is arranged at the middle position of the upper surface of the substrate. When the substrate vibrates, the vibration displacement signal is amplified by the swing mechanism. The matching block is arranged on the swing mechanism. Each of the side plates is arranged around the outside of the matching block and is in contact with the outer surface of the matching block. The lower end of the side plate is fixedly connected to the upper surface of the substrate, and a piezoelectric sheet is fixedly arranged on the lower part of the outer surface of each side plate.

[0006] Furthermore, the swing mechanism includes a thin supporting rod and a mass block, wherein the mass block is arranged at the upper end of the thin supporting rod and is detachably connected thereto, and the thin supporting rod is arranged perpendicular to the base plate, and a lower end thereof is detachably connected to the base plate.

[0007] Furthermore, the mass block and the thin supporting rod, and the thin supporting rod and the base plate are connected by threads.

[0008] Furthermore, the matching block is sleeved on the supporting thin rod, and the outer surface thereof is in contact with the upper inner surface of each side plate.

[0009] Furthermore, the matching block and the supporting thin rod are connected by interference fit.

[0010] Furthermore, the four side panels have the same specifications and are all arranged perpendicularly to the base plate. Two adjacent side panels are perpendicular to each other, and any two side panels are not connected.

[0011] Furthermore, the four side panels are respectively a first side panel, a second side panel, a third side panel and a fourth side panel, wherein the first side panel and the second side panel are parallel to each other, and the third side panel and the fourth side panel are parallel to each other.

[0012] Furthermore, mounting holes for mounting the energy harvester are arranged at the four corners of the substrate.

[0013] The present invention also provides a method for adjusting the above-mentioned omnidirectional vibration energy harvesting device, which is used to adjust the resonant frequency of the swing mechanism so that the resonant frequency is consistent with the vibration frequency, comprising the following steps:

[0014] S1: The frequency of the vibration source is measured by the sensor, that is, the vibration frequency;

[0015] S2: Select the length of the supporting thin rod and the weight and height of the mass block according to the calculation formula;

[0016] S3: According to the selected length of the thin supporting rod and the weight and height of the mass block, the length of the thin supporting rod and the weight and height of the mass block in the energy harvester are adjusted, and then the adjusted energy harvester is placed at the vibration source for energy harvesting.

[0017] Furthermore, in step S2, the calculation formula is as follows:

[0018]

[0019] Where f is the resonant frequency of the swing mechanism, Y is the elastic modulus of the supporting thin rod, I is the moment of inertia of the swing mechanism, l b is the length of the supporting rod, l m is the height of the mass block, m is the weight of the mass block, and f, Y, and I are known quantities.

[0020] Compared with the prior art, the present invention has the following advantages:

[0021] 1. It can realize omnidirectional energy collection, avoiding the complexity of structure and the difficulty of signal processing caused by arranging unidirectional collectors in different directions;

[0022] 2. Through the action of the mass block, the supporting thin rod and the matching block, the bending deformation of the piezoelectric sheet is larger than that caused by simply placing the side plate, while avoiding the disadvantage of low torsional deformation voltage signal;

[0023] 3. The natural frequency of the structure can be changed by adjusting the height of the supporting thin rod and the mass and height of the mass block to achieve resonance with the excitation frequency, increase the bending deformation of the piezoelectric film, and thus improve the piezoelectric voltage output. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 is a schematic diagram of the overall structure of the omnidirectional vibration energy harvesting device in an embodiment of the present invention;

[0025] Figure 2 is a partial structural schematic diagram of an omnidirectional vibration energy harvesting device in an embodiment of the present invention;

[0026] Figure 3 is a schematic diagram of the side structure of the omnidirectional vibration energy harvesting device in an embodiment of the present invention;

[0027] Figure 4 yes Figure 3 Schematic diagram of the cross-sectional structure along the AA axis. DETAILED DESCRIPTION

[0028] The following is a detailed description of an embodiment of the present invention. This embodiment is implemented on the premise of the technical solution of the present invention, and a detailed implementation method and a specific operation process are given, but the protection scope of the present invention is not limited to the following embodiment.

[0029] like Figures 1 to 4 As shown, this embodiment provides a technical solution: an omnidirectional vibration energy harvesting device, comprising a swing mechanism, a substrate 10, a matching block 2 and four side plates, the upper end of the swing mechanism is arranged at the middle position of the upper surface of the substrate 10, when the substrate 10 is vibrated, the vibration displacement signal is amplified by the swing mechanism, the matching block 2 is arranged on the swing mechanism, each of the side plates is arranged around the outside of the matching block 2, and is in contact with the outer surface of the matching block 2, the lower end of the side plate is fixedly connected to the upper surface of the substrate 10, and a piezoelectric sheet 9 is fixedly arranged on the lower part of the outer surface of each side plate.

[0030] In this embodiment, the swing mechanism includes a thin support rod 3 and a mass block 1, wherein the mass block 1 is disposed at the upper end of the thin support rod 3 and is detachably connected thereto, and the thin support rod 3 is disposed perpendicular to the substrate 10, and its lower end is detachably connected to the substrate 10. The detachable connection facilitates replacement of thin support rods 3 and mass blocks 1 of different specifications, thereby facilitating adjustment of the resonant frequency of the swing mechanism.

[0031] In this embodiment, the mass block 1 and the thin supporting rod 3 and the thin supporting rod 3 and the base plate 10 are both connected by threads.

[0032] In this embodiment, the matching block 2 is sleeved on the supporting thin rod 3, and the outer surface thereof is in contact with the upper inner surface of each side plate.

[0033] In this embodiment, the matching block 2 and the supporting thin rod 3 are connected by interference fit (detachable connection), the diameter of the thin rod is slightly larger than the hole diameter of the matching block, and the matching block 2 can be made of soft materials such as rubber and PDMS.

[0034] In this embodiment, the four side panels have the same specifications and are all arranged perpendicularly to the base plate 10 . Two adjacent side panels are perpendicular to each other, and no two side panels are connected.

[0035] In this embodiment, the four side panels are side panel 4, side panel 5, side panel 7 and side panel 8, wherein side panel 4 and side panel 5 are parallel to each other, and side panel 7 and side panel 8 are parallel to each other.

[0036] In this embodiment, mounting holes 101 are provided at the four corners of the substrate 10 for mounting the energy harvester.

[0037] In this embodiment, the side plate is a rectangular plate, the base plate 10 is a square plate, the mass block 1 is a sphere or a cube with a connection hole, and the matching block 2 is a cube with a connection hole.

[0038] The following is an example of the working process of the energy harvester:

[0039] When the substrate 10 is subjected to vibration along the positive direction of the x-axis, the swing mechanism composed of the supporting thin rod 3 and the mass block 1 will swing back and forth along the x-axis, and the swing mechanism can amplify the vibration displacement signal. When the mass block 1 swings back and forth along the x-axis, the matching block 2 swings back and forth following the supporting thin rod 3.

[0040] When the supporting thin rod 3 and the mass block 1 swing in the positive direction of the x-axis, the matching block 2 squeezes the side plate 5, causing the side plate 5 to bend and deform, driving the piezoelectric sheet 9 at the lower part of the outer surface of the side plate 5 to deform and generate a voltage signal. During the swing back, the matching block 2 squeezes the side plate 4, causing the piezoelectric sheet 9 at the lower part of the outer surface of the side plate 4 to bend and deform and generate a voltage signal. Such reciprocating motion causes the piezoelectric sheet to generate a continuous voltage signal, which can power the self-powered sensor.

[0041] When the supporting thin rod 3 and the mass block 1 swing in the negative direction of the x-axis, the matching block 2 squeezes the side plate 4, causing the side plate 4 to bend and deform, driving the piezoelectric sheet 9 at the lower part of the outer surface of the side plate 4 to deform and generate a voltage signal. During the swing back, the matching block 2 squeezes the side plate 5, causing the piezoelectric sheet 9 at the lower part of the outer surface of the side plate 5 to bend and deform and generate a voltage signal. Such reciprocating motion causes the piezoelectric sheet to generate a continuous voltage signal, which can power the self-powered sensor.

[0042] When the substrate 10 is subjected to vibration at an angle of 30° to the positive direction of the x-axis, the swing mechanism composed of the supporting thin rod 3 and the mass block 1 swings back and forth in the direction at an angle of 30° to the positive direction of the x-axis. At this time, the matching block 2 squeezes the side plates 5 and 8, causing the side plates 5 and 8 to bend and deform, driving the piezoelectric sheet 9 at the lower part of the outer surface of the side plate to deform and generate a voltage signal. When swinging back, the matching block 2 squeezes the side plates 4 and 7, causing the side plates 4 and 7 to bend and deform, driving the piezoelectric sheet 9 at the lower part of the outer surface of the side plate to deform and generate a voltage signal. Such reciprocating motion causes the piezoelectric sheet to generate a continuous voltage signal, which can power the self-powered sensor.

[0043] This embodiment also provides a method for adjusting the above omnidirectional vibration energy harvesting device, which is specifically described as follows:

[0044] When the vibration signal is very weak, in order to amplify and effectively collect the voltage signal, the height of the supporting thin rod and the mass of the mass block can be adjusted to adjust the resonant frequency of the swing mechanism composed of the thin rod and the mass block, so that its frequency is consistent with the vibration frequency to achieve a resonance effect, increase the bending deformation of the side plate, and achieve amplification of the voltage signal.

[0045] The specific adjustment process is as follows:

[0046] Step 1: Measure the frequency of the vibration source, i.e., the vibration frequency, through the sensor;

[0047] Step 2: Select the length of the supporting thin rod and the weight and height of the mass block according to the calculation formula. The calculation formula is as follows:

[0048]

[0049] Among them, f is the resonant frequency of the swing mechanism, Y is the elastic modulus of the supporting thin rod, I is the moment of inertia of the swing mechanism, f, Y, I are known quantities, l b is the length of the supporting rod, l m is the height of the mass block, m is the weight of the mass block;

[0050] It should be noted that according to the above formula, the length l of the supporting thin rod can be solved b , the height of the mass block l m, the weight m of the mass block, the designer can choose a reasonable solution according to the actual situation to determine the length l of the supporting thin rod b , the height of the mass block l m , the specific size of the weight m of the mass block.

[0051] When the mass block is a sphere, the height l of the mass block m is the diameter of the sphere; when the mass block is a cuboid (its upper and lower surfaces are squares), the side edge height of the cuboid is the height l of the mass block m .

[0052] Step 3: According to the calculated length of the thin supporting rod and the weight and height of the mass block, adjust the length of the thin supporting rod and the weight and height of the mass block in the energy harvester, and then place the adjusted energy harvester at the vibration source for energy harvesting.

[0053] In summary, the omnidirectional vibration energy harvesting device and its adjustment method in the above-mentioned embodiments can realize omnidirectional energy harvesting, avoiding the structural complexity and signal processing difficulties caused by arranging unidirectional harvesters in different directions; through the action of the mass block, the supporting thin rod and the matching block, the bending deformation of the piezoelectric sheet is larger than the deformation caused by simply placing the side plate, while avoiding the disadvantage of low torsional deformation voltage signal; the natural frequency of the structure can be changed by adjusting the height of the supporting thin rod and the mass and height of the mass block to achieve resonance with the excitation frequency, increase the bending deformation of the piezoelectric sheet, and thus improve the piezoelectric voltage output.

[0054] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. An omnidirectional vibration energy harvesting device and an adjustment method thereof, characterized in that: It includes a swing mechanism, a base plate, a matching block and four side plates. The upper end of the swing mechanism is arranged at the middle position of the upper surface of the base plate. When the base plate vibrates, the vibration displacement signal is amplified by the swing mechanism. The matching block is arranged on the swing mechanism. Each of the side plates is arranged around the outer side of the matching block and is in contact with the outer surface of the matching block. The lower end of the side plate is fixedly connected to the upper surface of the base plate. A piezoelectric sheet is fixedly arranged on the lower part of the outer surface of each side plate.

2. The omnidirectional vibration energy harvesting device according to claim 1, characterized in that: The swing mechanism includes a thin supporting rod and a mass block. The mass block is arranged at the upper end of the thin supporting rod and is detachably connected thereto. The thin supporting rod is arranged perpendicular to the base plate, and its lower end is detachably connected to the base plate.

3. The omnidirectional vibration energy harvesting device according to claim 2, characterized in that: The mass block and the thin supporting rod, as well as the thin supporting rod and the base plate are connected by threads.

4. The omnidirectional vibration energy harvesting device according to claim 2, characterized in that: The matching block is sleeved on the supporting thin rod, and the outer surface thereof is in contact with the upper inner surface of each side plate.

5. The omnidirectional vibration energy harvesting device according to claim 4, characterized in that: The matching block and the supporting thin rod are connected by interference fit.

6. The omnidirectional vibration energy harvesting device according to claim 4, characterized in that: The four side panels have the same specifications and are all arranged perpendicularly to the base plate. Two adjacent side panels are perpendicular to each other, and any two side panels are not connected.

7. The omnidirectional vibration energy harvesting device according to claim 4, characterized in that: The four side panels are respectively a first side panel, a second side panel, a third side panel and a fourth side panel, wherein the first side panel and the second side panel are parallel to each other, and the third side panel and the fourth side panel are parallel to each other.

8. The omnidirectional vibration energy harvesting device according to claim 7, characterized in that: The four corners of the substrate are all provided with mounting holes for mounting the energy collector.

9. A method for adjusting an omnidirectional vibration energy harvesting device, characterized in that: The method is used to adjust the resonant frequency of the oscillating mechanism in the energy harvester according to any one of claims 2 to 8 so that the resonant frequency is consistent with the vibration frequency, comprising the following steps: S1: The frequency of the vibration source is measured by the sensor, that is, the vibration frequency; S2: Select the length of the supporting thin rod and the weight and height of the mass block according to the calculation formula; S3: According to the selected length of the thin supporting rod and the weight and height of the mass block, the length of the thin supporting rod and the weight and height of the mass block in the energy harvester are adjusted, and then the adjusted energy harvester is placed at the vibration source for energy harvesting.

10. The omnidirectional vibration energy harvesting device and the adjustment method thereof according to claim 9, characterized in that: In step S2, the calculation formula is as follows: Among them, f is the resonant frequency of the swing mechanism, Y is the elastic modulus of the supporting thin rod, I is the moment of inertia of the swing mechanism, lb is the length of the supporting thin rod, lm is the height of the mass block, m is the weight of the mass block, and f, Y, and I are known quantities.

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