Micro-vibration energy-gathering type nano generator

Abstract

The utility model discloses a micro-vibration energy-gathering type nanometer generator, and belongs to the technical field of micro-energy sensing. According to the device, a fluorinated ethylene propylene copolymer top membrane and an elastic silica gel bottom membrane are innovatively adopted to construct an energy conversion structure, an efficient air pressure transmission system is formed through optimized membrane area proportion design, and weak mechanical vibration in the environment can be converted into effective electric energy to be output; the working principle is combined with the pneumatic transmission and friction nanometer power generation effect, the top film and the multi-walled carbon nanotube friction layer are driven by the air pressure change generated by deformation of the bottom film to make periodic contact-separation motion, so that conversion from mechanical energy to electric energy is achieved, and meanwhile the low-frequency vibration response characteristic is remarkably improved through the built-in air pressure balance through hole. The nano-generator adopts an all-solid-state modular design, has excellent weather resistance, stability and environmental adaptability, can be widely applied to the micro-energy supply field of Internet of Things sensors, wearable equipment and the like, and effectively solves the problem that a traditional nano-generator is insufficient in conversion efficiency in a weak-energy environment.

Description

Micro-vibration focused energy nanogenerator Technical Field

[0001] This utility model relates to the field of micro-energy sensing technology, specifically to a micro-vibration energy-concentrating nanogenerator. Background Technology

[0002] Against the backdrop of the rapid development of the Internet of Things and low-power sensing technologies, how to efficiently collect and utilize micromechanical energy (such as sound waves and touch) in the environment has become a key technological bottleneck for realizing self-powered systems. Mechanical vibrations in the environment generally exhibit low-frequency (<100 Hz) and weak-amplitude characteristics, making it difficult for traditional electromagnetic generators that rely on high-frequency resonance mechanisms to efficiently convert this type of energy. Although triboelectric nanogenerators (TENGs) show advantages such as low material cost and flexible structural design in low-frequency energy harvesting, their inherent contact-separation working mechanism has a high threshold for input energy intensity, resulting in the inability to effectively trigger the separation of the electrified layer under micro-Newton level external force excitation. This limitation severely restricts their application efficiency in capturing energy in weak environments.

[0003] Currently, improvements in nanogenerator technology primarily focus on device structure optimization, generally employing two methods: The first utilizes precision machining techniques such as laser etching and nanoimprinting to create micron- or nanometer-scale fine structures on the surface of the tribological layer, significantly increasing the actual contact area between materials; the second involves designing gradient materials or composite structures to adjust the mechanical properties of the contact layer, thereby improving the efficiency of the contact separation process. While both methods effectively enhance the energy conversion performance of nanogenerators, neither fundamentally solves the energy capture challenge under micro-excitation scenarios. Under conditions of weak mechanical energy and ultra-low frequency vibration, the van der Waals forces between the charged layers of traditional TENGs far exceed the external input mechanical energy, preventing effective triggering of the contact separation process. This critical bottleneck severely restricts their practical application value in environmental energy harvesting.

[0004] Existing research has also explored piezoelectric or electromagnetic composite energy conversion mechanisms, attempting to improve energy harvesting efficiency through multi-physics coupling. However, these hybrid structures often suffer from problems such as high device complexity, severe mismatch between the inherent resonant frequency of piezoelectric materials and the frequency band of environmental micro-vibrations, and sharp attenuation of the induced electromotive force of electromagnetic units under micro-displacement conditions. These inherent defects make it difficult for piezoelectric or composite generators to effectively capture low-frequency weak excitation signals in practical applications.

[0005] Therefore, it is crucial to develop a novel optimized mechanical energy transfer path scheme to address the shortcomings of existing nanogenerators in energy harvesting in weak environments. Such innovative designs need to be able to automatically sense and efficiently harvest minute amounts of mechanical energy from the environment under weak vibration conditions, particularly achieving stable and reliable energy conversion for low-frequency vibrations. This technological breakthrough will not only significantly improve energy harvesting efficiency but will also provide sustainable micro-energy solutions for applications such as IoT sensors and wearable devices, possessing broad market prospects and practical value. Summary of the Invention

[0006] The purpose of this invention is to address the shortcomings of existing technologies and provide a micro-vibration energy-concentrating nanogenerator. By optimizing the design of the mechanical energy transmission path, it can effectively capture and convert weak vibration energy under weak excitation environments, thereby achieving self-driven sensing functionality.

[0007] The technical solution of this utility model is as follows: a micro-vibration energy-concentrating nanogenerator, comprising: a base unit, which adopts a hollow cavity structure for receiving and amplifying environmental vibration signals; a top cover unit, located on top of the base unit, which has a downwardly recessed cavity structure, wherein the bottom region of the cavity is provided with an electrode layer and a multi-walled carbon nanotube friction layer; and an energy-concentrating unit, comprising a flexible membrane structure for sealing the openings at both ends of the base unit.

[0008] The top membrane structure integrates an electrode layer, forming a tunable dynamic gap between it and the multi-walled carbon nanotube friction layer.

[0009] The bottom membrane structure deforms under weak excitation conditions, inducing changes in the cavity air pressure, which drives the top membrane and the multi-walled carbon nanotube friction layer to produce periodic contact-separation motion, realizing the conversion of mechanical energy into electrical energy.

[0010] Furthermore, the base unit is generally truncated conical or frustum-shaped.

[0011] Furthermore, the top cover unit includes:

[0012] The base section serves as the main load-bearing component;

[0013] The enclosure extends circumferentially along the base portion and is integrally formed with the base portion, together forming a functional chamber for accommodating the electrode layer and the multi-walled carbon nanotube friction layer.

[0014] Furthermore, the bottom membrane is made of elastic silicone material with a thickness of 0.4~0.6 mm; the top membrane is made of FEP material with a thickness of 0.02~0.05 mm; and the area ratio of the top membrane to the bottom membrane is 1:20~30.

[0015] Furthermore, the dynamic gap between the top membrane and the multi-walled carbon nanotube friction layer is 0.2~1 mm, preferably 0.3~0.5 mm.

[0016] Furthermore, a through-hole unit for air pressure balance is provided on the base.

[0017] Furthermore, the via unit comprises an array of vias arranged in a concentric ring.

[0018] Furthermore, the through-hole unit consists of three concentric ring-shaped arrays of through holes on the surface of the substrate, including six small holes arranged at equal intervals around the inner ring, and six large holes arranged at equal intervals around the middle and outer rings.

[0019] Furthermore, the diameter of the small hole is 0.8~1.2 mm, and the diameter of the large hole is 1.8~2.4 mm.

[0020] Furthermore, the top cover unit and the base unit are manufactured using additive manufacturing processes, and the molding material includes biodegradable polymer materials.

[0021] The beneficial effects of this utility model are as follows:

[0022] 1. The energy gathering unit disclosed in this application adopts a synergistic design of an elastic silicone bottom membrane and a fluorinated ethylene propylene copolymer (FEP) top membrane, and constructs a pressure transmission system through a specific area ratio of 20:1 to 30:1; firstly, the environmental micro-vibration is converted into membrane deformation, and then the displacement is amplified through the area difference, ultimately driving the FEP membrane to produce effective contact separation. This structure enables the device to exhibit excellent vibration signal sensing capability in the low frequency range.

[0023] 2. The micro-vibration energy-concentrating nanogenerator disclosed in this application innovatively combines a pneumatic transmission mechanism with the principle of triboelectric nanogenerators. It drives changes in air pressure through the deformation of the bottom membrane, thereby inducing displacement of the top membrane and generating a contact electrification effect, achieving efficient conversion of environmental mechanical energy into electrical energy. Its modular design allows for adjustment of energy concentration parameters according to application scenarios, and its all-solid-state characteristics ensure long-term stable operation in harsh environments, showing excellent application prospects in the field of micro-energy supply, such as IoT sensors.

[0024] 3. This application establishes a dynamic pressure balance channel between the internal and external environments by designing a through-hole array on the top cover unit, effectively reducing the air damping effect. This design enables the bottom membrane to respond quickly to low-frequency mechanical vibrations in the environment, thereby improving the overall sensitivity of the energy harvesting system to weak vibration signals. The entire technical solution provides an innovative energy harvesting solution for self-powered microsystems. Attached Figure Description

[0025] Figure 1 is an isometric view of a micro-vibration focused energy nanogenerator;

[0026] Figure 2 is a front view schematic diagram of a micro-vibration focused energy nanogenerator;

[0027] Figure 3 is a longitudinal cross-sectional view of a micro-vibration focused energy nanogenerator;

[0028] Figure 4 is a top view of the base unit;

[0029] Figure 5 is a longitudinal sectional view of the base unit;

[0030] Figure 6 is a top view of the top cover unit;

[0031] Figure 7 shows the sensitivity verification results;

[0032] Figure 8 shows the airflow response test results;

[0033] Figure 9 shows the environmental vibration detection results;

[0034] Figure 10 is a flowchart of the self-powered test system;

[0035] Figure 11 shows the real-time impact force monitoring curve;

[0036] Figure 12 shows the results of micro-vibration response signal processing;

[0037] Among them, 1-base unit, 2-top cover unit, 3-energy gathering unit;

[0038] 21-Disc body, 22-Annular sidewall, 23-Concave cavity, 24-Multi-walled carbon nanotube friction layer;

[0039] 31-Top membrane, 32-Bottom membrane;

[0040] 211 - Inner ring array, 212 - Middle ring array, 213 - Outer ring array. Detailed Implementation

[0041] The following embodiments further illustrate the content of this utility model, but should not be construed as limiting the utility model. Any modifications and substitutions made to the methods, steps, or conditions of this utility model without departing from its essence are within the scope of this utility model.

[0042] Example 1

[0043] This embodiment discloses a micro-vibration energy-concentrating nanogenerator, the specific structure of which is shown in Figures 1-6, including a base unit 1, a top cover unit 2, and an energy-concentrating unit 3.

[0044] The base unit 1 adopts a hollow cavity design and is truncated conical in shape. It can amplify external vibration deformation by utilizing the geometric characteristics of the hollow cavity. Its bottom radius a is 50 mm, top radius b is 14 mm, height h is 15 mm, and thickness e is 4 mm (Figure 5).

[0045] The top cover unit 2 is fixedly attached to the top of the base unit 1 and adopts an integrally formed annular concave disk structure, which consists of a disk body 21 and annular sidewalls 22. The outer edge of the annular sidewalls 22 is aligned with the outer edge of the disk body 21, and the outer edge of the annular sidewalls 22 is also aligned with the top edge of the base unit 1. After the annular sidewalls 22 and the disk body 21 are enclosed, a concave cavity 23 structure is formed at the bottom of the disk body 21. In the region of the concave cavity 23, an aluminum electrode layer (not shown in the figure) and a multi-walled carbon nanotube friction layer 24 are sequentially integrated from top to bottom. The multi-walled carbon nanotube friction layer 24 serves as the positively charged material of the triboelectric nanogenerator.

[0046] The multi-walled carbon nanotube friction layer 24 was prepared by coating with multi-walled carbon nanotube solution provided by Shenzhen Kaihong New Materials Co., Ltd., forming a uniform coating with a thickness of about 40 micrometers.

[0047] The energy gathering unit 3 consists of a top membrane 31 and a bottom membrane 32. The top membrane 31 and the bottom membrane 32 are used to seal the top and bottom openings of the base unit 1, respectively. Together, they form a sealed chamber structure. The top membrane 31 has the dual functions of a negatively charged friction layer and a mechanical response layer. Its lower surface integrates an aluminum electrode as a charge lead-out terminal (not shown in the figure). It maintains a dynamic gap of 0.4 mm with the multi-walled carbon nanotube friction layer 24 of the top cover unit 2. Energy conversion is achieved by triggering periodic contact-separation motion through vibration.

[0048] The bottom membrane 32 is made of food-grade 10-degree liquid silicone provided by Shenzhen Puston Silicone Materials Co., Ltd., and is made into an elastic silicone substrate through a 1:1 mixing and curing process. The elastic properties of the bottom membrane can enhance the system's adaptability to low-frequency vibration. The thickness of the bottom membrane 32 is 0.5 mm. The top membrane 31 is made of fluorinated ethylene propylene copolymer (FEP) film material provided by Taizhou Chenguang Plastics Co., Ltd., with a thickness of 0.03 mm.

[0049] The area ratio of the top membrane 31 to the bottom membrane 32 is 1:20.

[0050] Energy gathering unit 3 and base unit 1 together constitute an energy gathering structure, achieving efficient energy conversion through mechanical-pneumatic coupling. When environmental micro-vibrations act on the elastic base membrane 32, the base membrane 32 undergoes elastic deformation, causing periodic fluctuations in the internal air pressure of base unit 1. This drives the top membrane 31 (FEP negatively charged layer) and the multi-walled carbon nanotube friction layer 24 (positively charged layer) of top cover unit 2 to produce regular contact-separation motion. Based on the triboelectric effect, charge transfer occurs when the two heterogeneous materials come into contact, and an alternating potential difference is formed between the aluminum electrodes due to electrostatic induction during separation, ultimately outputting alternating current energy.

[0051] A through-hole unit is provided on the disk body 21. This design effectively reduces the air damping effect during system movement by establishing a dynamic air pressure balance channel between the internal and external environments. This air pressure compensation mechanism enables the elastic bottom membrane 32 to overcome the sensitivity limitations of traditional structures, achieving rapid response to low-frequency amplitude mechanical vibrations in the environment. This significantly improves the detection capability of the entire energy harvesting system for weak vibration signals and can provide a reference micro-vibration acquisition solution for self-powered sensing of IoT edge devices. The aluminum electrode layer at the bottom of the disk body 21 is cut to ensure that its integration into the bottom of the disk body 21 will not cause positional interference to the through-hole unit, ensuring that the through-hole unit is always in a vertically continuous state.

[0052] The through-hole unit consists of three concentric ring arrays of through holes on the surface of the disk body 21. The inner ring array 211 includes six small holes evenly distributed around the circumference, with a hole diameter d1 of 1 mm and a distribution circle radius R1 (distance from the center O of the disk body to the center O1 of the small hole) of 5 mm. The middle ring array 212 includes six large holes evenly distributed around the circumference, with a hole diameter d2 of 2 mm and a distribution circle radius R2 (distance from the center O of the disk body to the center O2 of the large hole) of 9.5 mm. The outer ring array 213 includes six large holes evenly distributed around the circumference, with a hole diameter d3 of 2 mm and a distribution circle radius R3 (distance from the center O of the disk body to the center O3 of the large hole) of 13.5 mm. The center lines connecting the three holes in the inner, middle, and outer ring arrays all pass through the center of the disk body 21, meaning that there are three collinear holes (1 small hole + 2 large holes) on the same radial straight line, forming a symmetrical energy transfer path.

[0053] Both the top cover unit 2 and the base unit 1 are manufactured using 3D printing technology, with polylactic acid (PLA) as the printing material. Due to its good mechanical properties and environmental characteristics, it meets the requirements of green manufacturing.

[0054] Induction test

[0055] 1. Sensitivity Verification Test: Controllable micro-friction (friction force <4 N) was applied artificially to the surface of the substrate 32, and the output voltage signal was recorded in real time using a PXI-4070 high-precision acquisition card. Experimental data (Figure 7) show that the nanogenerator can stably output a 1 V pulse voltage, confirming its excellent electromechanical conversion characteristics for surface friction excitation.

[0056] 2. Airflow response test: The ability of the micro-vibration focusing nanogenerator disclosed in this embodiment to sense airflow was verified by blowing air onto the bottom membrane. The voltage signal was acquired using a PXI-4070 acquisition card, and the results are shown in Figure 8. The results show that the device can effectively convert airflow kinetic energy into electrical energy, providing a new self-powered solution for airflow sensing.

[0057] 3. Environmental vibration detection: To verify the ability of the micro-vibration energy-concentrating nanogenerator disclosed in this embodiment to sense environmental vibration, the device was placed on a standard experimental table and environmental vibration excitation was simulated by manually tapping the table. The output voltage signal change was monitored in real time using a PXI-4070 acquisition card. The experimental results (Figure 9) show that the device can effectively capture and convert mechanical vibration energy, verifying its practical performance in the field of environmental vibration sensing.

[0058] 4. To verify the detection performance of the micro-vibration focused nanogenerator on weak vibration signals, this study constructed a self-powered testing system consisting of a nanogenerator, a 100x attenuation probe, and a PXI series acquisition card (4070 / 4462) (see Figure 10). In the experiment, the device was fixed on a standard experimental platform, and a force hammer connected to the PXI-4462 acquisition card was used for precise excitation. A standard impact force of approximately 2 N was monitored and maintained in real-time using a LabVIEW program (Figure 11). The electrical signal output by the nanogenerator was conditioned by the attenuation probe and then acquired with high precision by the PXI-4070 acquisition card. Finally, the effective signal waveform was obtained through LabVIEW digital filtering (Figure 12), fully verifying the device's sensitive response characteristics to micro-vibration signals.

[0059] Based on the principle of self-powered operation, this technology can effectively respond to weak mechanical excitations without the need for an external power source. It features strong environmental adaptability and low maintenance costs, providing innovative passive sensing solutions for fields such as environmental monitoring systems, IoT terminal devices, and human-machine interfaces.

[0060] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. However, the above description is only a specific embodiment of this utility model, and the technical features of this utility model are not limited thereto. Any other embodiments derived by those skilled in the art without departing from the technical solution of this utility model should be included within the scope of this utility model.

Claims

1. A micro-vibration focused energy nanogenerator, characterized in that, include: The base unit adopts a hollow cavity structure to receive and amplify environmental vibration signals; The top cover unit, located on top of the base unit, has a downwardly recessed cavity structure. The bottom region of the cavity is provided with an electrode layer and a multi-walled carbon nanotube friction layer. The energy gathering unit includes a flexible membrane structure for sealing the openings at both ends of the base unit: a top membrane structure, which integrates the electrode layer and forms an adjustable dynamic gap with the multi-walled carbon nanotube friction layer; and a bottom membrane structure, which deforms under weak excitation conditions to induce changes in the cavity air pressure, driving the top membrane and the multi-walled carbon nanotube friction layer to produce periodic contact-separation motion, thereby realizing the conversion of mechanical energy into electrical energy.

2. The micro-vibration focused energy nanogenerator as described in claim 1, characterized in that, The base unit is generally truncated conical or frustum-shaped.

3. The micro-vibration focused energy nanogenerator as described in claim 1, characterized in that, The top cover unit includes: a base portion, which serves as the main load-bearing body; and a enclosure portion, which extends circumferentially along the base portion and is integrally formed with the base portion, together forming a functional chamber for accommodating the electrode layer and the multi-walled carbon nanotube friction layer.

4. The micro-vibration focused energy nanogenerator as described in claim 1, characterized in that, The bottom membrane is made of elastic silicone material with a thickness of 0.4–0.6 mm; the top membrane is made of FEP material with a thickness of 0.02–0.05 mm; the area ratio of the top membrane to the bottom membrane is 1:20–30.

5. The micro-vibration focused energy nanogenerator as described in claim 1, characterized in that, The dynamic gap between the top membrane and the multi-walled carbon nanotube friction layer is 0.2–1 mm.

6. The micro-vibration focused energy nanogenerator as described in claim 3, characterized in that, The base is provided with through-hole units for air pressure balance.

7. The micro-vibration focused energy nanogenerator as described in claim 6, characterized in that, The via unit comprises an array of vias arranged in a concentric ring.

8. The micro-vibration focused energy nanogenerator as described in claim 7, characterized in that, The through-hole unit consists of three concentric ring-shaped arrays of through holes on the surface of the substrate, including six small holes arranged at equal intervals around the inner ring, and six large holes arranged at equal intervals around the middle and outer rings.

9. The micro-vibration focused energy nanogenerator as described in claim 8, characterized in that, The diameter of the small hole is 0.8–1.2 mm, and the diameter of the large hole is 1.8–2.4 mm.

10. The micro-vibration focused energy nanogenerator as described in claim 1, characterized in that, The top cover unit and the base unit are manufactured using additive manufacturing processes, and the molding materials include biodegradable polymer materials.

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