A friction nano and electromagnetic composite energy harvesting device

Abstract

The present invention relates to the field of energy collection technology, and specifically to a friction nano and electromagnetic composite energy harvesting device, comprising: a first plate is arranged on the inner wall of a box body; a second magnet is arranged above the first magnet and repels the first magnet and is in a suspended state; a second plate is arranged on the periphery of the second magnet; the first plate and the second plate are arranged in an interdigitated manner; a friction layer is provided on the second plate, and a metal electrode is provided on the first plate; the second plate contacts, collides and separates from the first plate under a vibration environment; the coil is located above the second magnet; the present application contacts, collides and separates the friction layer on the second plate through the metal electrode on the first plate. The above collision increases the vibration frequency of the second magnet, achieving the effect of frequency up-conversion and frequency extension, converting low-frequency vibration into high-frequency output, and increasing the power output of the coil electromagnetic power generation.

Description

Technical Field

[0001] The present invention relates to the field of energy collection technology, and in particular to a friction nano and electromagnetic composite energy harvesting device. Background Art

[0002] With the advancement of digital grid construction, the application scale of power sensors has increased dramatically. Traditional battery power supply methods have placed great pressure on the operation and maintenance of power sensors. Achieving self-powered power sensors through ambient energy harvesting is an alternative and supplementary solution to battery power supply.

[0003] Vibration energy is widely present in power generation equipment and overhead lines. Current vibration energy harvesting technologies primarily include frictional, electromagnetic, and piezoelectric vibration harvesting. Piezoelectric vibration harvesting leverages the piezoelectric effect of materials and offers advantages such as simple structure, high output voltage, ease of manufacturing, and strong anti-interference capabilities. However, its practical application is limited by issues such as low output current, susceptibility to depolarization, and material brittleness. Electromagnetic vibration harvesting utilizes ambient vibration to alter the relative position of a permanent magnet and a magnetic induction coil, generating an induced potential. While it offers advantages such as simple structure, high output power, and high reliability, its typical operating frequency results in low efficiency for harvesting low-frequency vibrations. Furthermore, its output performance is affected by the number of coil turns and the size of the permanent magnet, making it difficult to miniaturize and limiting its volumetric energy density. Frictional vibration harvesting, based on the coupling of triboelectric charging and electrostatic induction, effectively harvests low-frequency vibration energy. Its output is typically a pulse signal with a high output voltage but low output power. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defect of low efficiency in collecting low-frequency vibrations by using a single electromagnetic vibration energy harvesting method.

[0005] In order to achieve the above objectives, the present invention provides a tribo-nano and electromagnetic composite energy harvesting device, comprising:

[0006] A box body having a cavity with an open top; a plurality of first plates spaced apart are horizontally arranged on the inner side wall of the box body;

[0007] A first magnet is disposed on the bottom wall of the box, with the first magnetic pole of the first magnet facing upward;

[0008] A second magnet is disposed above the first magnet, with the second magnetic pole of the second magnet facing downward, the first magnetic pole and the second magnetic pole are mutually repelling magnetic poles, and the second magnet is in a suspended state; a plurality of spaced second plates are horizontally disposed on the periphery of the second magnet; the plurality of first plates and the plurality of second plates are arranged in an interdigitated manner; a friction layer is provided on the surface of the second plate opposite to the first plate, and a metal electrode is provided on the surface of the first plate opposite to the second plate; the second plate is suitable for contacting, colliding with, and separating from the first plate in a vibration environment;

[0009] A cover body, adapted to close the top opening of the box body;

[0010] The coil is arranged on the bottom surface of the cover body and is located above the second magnet.

[0011] Optionally, the electronegativity of the friction layer is greater than the electronegativity of the metal electrode; and the coil, the first plate and the second plate are suitable for jointly obtaining electrical energy under a vibration environment.

[0012] Optionally, in an initial state, a gap is provided between the first plate and the second plate; the initial state is a state when the friction nano and electromagnetic composite energy harvesting device is not vibrating.

[0013] Optionally, the coil is fixed to the bottom surface of the cover body by a detachable fastener.

[0014] Optionally, a groove is provided on the bottom wall of the box body, and the first magnet is located in the groove.

[0015] Optionally, it also includes:

[0016] The guide shaft is vertically arranged in the box body, the bottom end of the guide shaft is located in the groove of the box body, and the guide shaft and the box body are made as one piece; and the first magnet and the second magnet are both sleeved on the guide shaft.

[0017] Optionally, the coil, the first magnet and the second magnet are all coaxially arranged.

[0018] Optionally, the top end of the guide shaft is located in the circular hole of the coil.

[0019] Optionally, the metal electrode includes: a plurality of first metal electrodes arranged on the top surface of the first plate and a plurality of second metal electrodes arranged on the bottom surface of the first plate; the plurality of first metal electrodes are arranged in parallel through a first wire; and the plurality of second metal electrodes are arranged in parallel through a second wire, thereby realizing the interdigital output of the first metal electrode and the second metal electrode.

[0020] Optionally, the first plate members and the second plate members adjacent to each other are arranged at the same interval.

[0021] The above technical solution of the present invention has the following advantages over the prior art:

[0022] 1. The triboelectric nano- and electromagnetic composite energy harvesting device provided by the present invention comprises: a housing having a cavity with a top opening; a plurality of spaced first plates horizontally arranged on the inner side wall of the housing; a first magnet disposed on the bottom wall of the housing, with the first pole of the first magnet facing upward; a second magnet disposed above the first magnet, with the second pole of the second magnet facing downward, the first and second poles being mutually repulsive, and the second magnet being in a suspended state; a plurality of spaced second plates horizontally arranged around the outer periphery of the second magnet; a plurality of the first plates and a plurality of the second plates being arranged in an interdigitated arrangement; a friction layer being provided on the surface of the second plate opposite to the first plate, and a metal electrode being provided on the surface of the first plate opposite to the second plate; the second plate being adapted to contact, collide with, and separate from the first plate in a vibration environment; a cover adapted to close the top opening of the housing; a coil disposed on the bottom surface of the cover, and the coil being located above the second magnet; the present application adopts the above technical solution, through which the metal electrodes on the first plate contact, collide with, and separate from the friction layer on the second plate. The collision between the first plate and the second plate increases the vibration frequency of the second magnet, broadens the energy capture frequency band, achieves the effect of frequency up-conversion and frequency expansion, converts low-frequency vibration excitation in life into high-frequency output, and increases the electrical energy output of the coil electromagnetic power generation.

[0023] 2. The electronegativity of the friction layer of the present invention is greater than that of the metal electrode; the coil, first plate, and second plate are suitable for jointly obtaining electrical energy in a vibration environment; this application adopts the above technical solution, taking advantage of the fact that the friction layer is more likely to obtain electrons than the metal electrode; and generates electrical energy through the contact, collision, and separation between the metal electrode on the first plate and the friction layer on the second plate, i.e., friction vibration energy extraction; and combines the movement of the coil relative to the second magnet to generate electrical energy, i.e., electromagnetic vibration energy extraction. The two vibration energy extraction technologies are combined and share structural components, further improving the output power of electromagnetic energy extraction; and through the combination of friction vibration energy extraction and electromagnetic vibration energy extraction, the output power is increased, overcoming the disadvantage of low output power of single friction vibration energy extraction, which is conducive to improving volume energy density.

[0024] 3. In the initial state of the present invention, a gap is provided between the first plate and the second plate; the initial state is the state when the friction nano and electromagnetic composite energy harvesting device is not vibrating; the present application adopts the above technical solution to ensure that the second magnet is in a suspended state, and in a vibrating environment, the second magnet drives the second plate to collide with the first plate.

[0025] 4. The coil described in the present invention is fixed to the bottom surface of the cover body by a detachable fastener; this application adopts the above technical solution to facilitate the fastening and disassembly of the coil.

[0026] 5. In the present invention, a groove is provided on the bottom wall of the box body, and the first magnet is located in the groove; this application adopts the above technical solution to stably fix the first magnet through the groove.

[0027] 6. The friction nano and electromagnetic composite energy harvesting device provided by the present invention also includes: a guide shaft, which is vertically arranged in the box body, the bottom end of the guide shaft is located in the groove of the box body, and the guide shaft and the box body are made as one piece; and the first magnet and the second magnet are both mounted on the guide shaft; this application adopts the above technical solution, and through the guide shaft, ensures that the second magnet only produces up and down movement to prevent deviation.

[0028] 7. The coil, first magnet and second magnet described in the present invention are all coaxially arranged; this application adopts the above technical solution, and through the coaxial arrangement, ensures a compact structure and a stable dynamic balance of the second magnet.

[0029] 8. The top end of the guide shaft described in the present invention is located in the circular hole of the coil; this application adopts the above technical solution to ensure the stability of the guide shaft.

[0030] 9. The metal electrodes described in the present invention include: multiple first metal electrodes arranged on the top surface of the first plate and multiple second metal electrodes arranged on the bottom surface of the first plate; multiple first metal electrodes are arranged in parallel through a first wire; multiple second metal electrodes are arranged in parallel through a second wire; this application adopts the above technical solution, the first metal electrodes generate electrical energy in parallel through the first wire, and the second metal electrodes generate electrical energy in parallel through the second wire.

[0031] 10. In the present invention, the first plate and the second plate adjacent to each other are arranged at the same interval; this application adopts the above technical solution, and through the technical solution of setting the same interval, multiple friction layers are simultaneously contacted and separated under external vibration, thereby realizing the simultaneous contact and separation of multiple friction layers, forming a superposition of multiple layers of current, thereby increasing the energy capture efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0033] Figure 1 A schematic diagram of the three-dimensional structure of the tribo-nano and electromagnetic composite energy harvesting device after the cover is opened provided in an embodiment of the present invention;

[0034] Figure 2A schematic diagram of the internal three-dimensional structure of the tribo-nano and electromagnetic composite energy harvesting device provided in an embodiment of the present invention;

[0035] Figure 3 A schematic diagram of the installation structure of a coil provided in an embodiment of the present invention;

[0036] Figure 4 This is a schematic diagram of the installation structure of the first magnet provided in an embodiment of the present invention;

[0037] Figure 5 Schematic diagram of the three-dimensional structure of the second magnet provided in an embodiment of the present invention;

[0038] Figure 6 This is a schematic diagram of the external circuit structure of the interdigital stacked friction nano-vibration energy harvesting unit provided in an embodiment of the present invention;

[0039] Figure 7 Schematic diagram of the power generation principle of the interdigitated stacked friction nano-vibration energy harvesting unit provided in an embodiment of the present invention.

[0040] Description of reference numerals:

[0041] 1. Cover; 2. First plate; 3. Guide shaft; 4. Second magnet; 5. Second plate; 6. Box; 7. Coil; 8. First fastener; 9. Second fastener; 10. First magnet; 11. Metal electrode; 12. Friction layer. DETAILED DESCRIPTION

[0042] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0043] In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate and simplify the description of the present invention. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation, and therefore should not be construed as limitations on the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0044] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0045] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0046] like Figures 1 to 7 A specific embodiment of the friction nano and electromagnetic composite energy harvesting device shown includes: a box body 6, a first magnet 10, a second magnet 4, a coil 7 and a guide shaft 3 located in the box body 6, and a cover body 1 arranged on the top surface of the box body 6.

[0047] like Figure 1 and Figure 5 As shown, the box body 6 has a cavity with an open top, and the box body 6 is a square box; a plurality of first plates 2 are horizontally arranged on the four inner walls of the box body 6; specifically, one first plate 2 is horizontally arranged on the four inner walls of the box body 6. The first magnet 10 is arranged on the bottom wall inside the box body 6. Specifically, a groove is provided on the bottom wall inside the box body 6, and the first magnet 10 is located in the groove. The first magnetic pole of the first magnet 10 is arranged upward. The second magnet 4 is arranged directly above the first magnet 10, the second magnet 4 is cylindrical, and the second magnetic pole of the second magnet 4 is arranged downward, the first magnetic pole and the second magnetic pole are mutually repelling magnetic poles, and the second magnet 4 is in a suspended state, that is, a magnetic levitation mechanism is formed. The guide shaft 3 is vertically arranged in the box body 6, and a circular hole is provided in the middle of the first magnet 10 and the second magnet 4. The second magnet 4 is sleeved on the guide shaft 3 through the circular hole, so that the second magnet 4 can only move up and down. The bottom end of the guide shaft 3 is located in the groove of the box body 6. The guide shaft 3 and the box body 6 are made as one piece, and the first magnet 10 is also sleeved on the guide shaft 3.

[0048] A plurality of spaced second plates 5 are horizontally arranged around the second magnet 4. Specifically, two spaced second plates 5 are horizontally arranged around the second magnet 4. One first plate 2 and two second plates 5 are arranged in an interdigitated manner. The interdigitated arrangement means that a plurality of first plates 2 are distributed on the four inner walls of the box 6, and a corresponding plurality of second plates 5 are distributed around the second magnet 4. The first plates 2 and the second plates 5 located in the same vertical direction are arranged in an alternating manner. Specifically, the first plate 2 is positioned between two adjacent second plates 5. A friction layer 12 is provided on the surface of the second plate 5 facing the first plate 2, and a metal electrode 11 is provided on the surface of the first plate 2 facing the second plate 5. The friction layer 12 has a greater electronegativity than the metal electrode 11, making it more susceptible to electron absorption than the metal electrode 11. Specifically, the friction layer 12 can be made of a friction material that readily absorbs electrons, such as PTFE (polytetrafluoroethylene), PVDF (polyvinylidene fluoride), and FEP (propylene copolymer). The metal electrode 11 can be a conductive metal that readily loses electrons, such as aluminum, copper, and steel. In the initial state, a gap exists between the first plate 2 and the second plate 5; this initial state is when the triboelectric nano- and electromagnetic composite energy harvesting device is not vibrating. The second plate 5 is adapted to contact, collide, and separate from the first plate 2 under vibration, thereby forming an interdigitated stacked triboelectric nano-vibration energy harvesting unit. Furthermore, multiple interdigitated stacked triboelectric nano-vibration energy harvesting units can be provided.

[0049] The cover 1 is suitable for closing the top opening of the box 6. The coil 7 is arranged on the bottom surface of the cover 1. Specifically, the coil 7 is a ring coil, and ear plates are respectively provided on the two opposite outer sides of the coil 7. The two ear plates are connected by two detachable fasteners (i.e. Figure 3 The first fastener 8 and the second fastener 9) are fixed to the bottom surface of the cover body 1. The first fastener 8 and the second fastener 9 are both screws. A conical countersunk hole is provided on the ear plate; the screw is a countersunk screw to reduce the interference of the protruding screw on other parts. The coil 7 is located directly above the second magnet 4; that is, an electromagnetic vibration energy acquisition unit is formed, and electrical energy is generated by cutting the magnetic flux lines of the second magnet 4 by the coil 7. The coil 7, the first magnet 10, and the second magnet 4 are all coaxially arranged. The top end of the guide shaft 3 is located in the circular hole of the coil 7, and the upper end of the guide shaft 3 is fixed in the circular hole in the middle of the coil 7. The coil 7, the first plate 2 and the second plate 5 are suitable for obtaining electrical energy together in a vibration environment.

[0050] like Figure 6As shown, the metal electrode 11 includes: 4(n-1) first metal electrodes disposed on the top surface of the first plate 2 and 4(n-1) second metal electrodes disposed on the bottom surface of the first plate 2. The 4(n-1) first metal electrodes are connected in parallel via a first wire; the 4(n-1) second metal electrodes are connected in parallel via a second wire, thereby achieving interdigital output between the first and second metal electrodes. A load R is connected between the first and second wires. The 4(n-1) first plates 2 and 4n second plates 5 are arranged in an interdigitated pattern, with adjacent first and second plates 2 and 5 disposed at equal intervals. Multiple friction layers 12 simultaneously contact and separate under external vibration, achieving the superposition of multiple layers of current, thereby increasing energy capture efficiency.

[0051] The working process of a cross-finger stacked friction nano vibration energy harvesting unit of the friction nano and electromagnetic composite energy harvesting device described in this application is briefly described as follows: Figure 7 As shown, when the entire tribo-electromagnetic composite energy harvesting device vibrates up and down, the second plate 5 on the second magnet 4 and the first plate 2 on the housing 6 collide with each other; the friction layer 12 and the metal electrode 11 come into contact and separate, generating electrical energy. Current is generated at the lower and upper portions of the first plate 2. Wires are used to connect the first and second metal electrodes on the first plate 2 in parallel, forming an interdigitated, stacked tribo-electromagnetic vibration energy harvesting unit. This achieves in-phase current output and increases output power. Specifically, initially, the first plate 2 and the second plate 5 are not in contact, the tribo-electromagnetic composite energy harvesting device vibrates, and the second metal electrode contacts the friction layer 12. Because the friction layer 12 has a stronger electron-accepting ability than the second metal electrode, charge transfer occurs at the contacting portions, resulting in a positive charge on the surface of the second metal electrode and an equal amount of negative charge on the surface of the friction layer 12. When the second metal electrode is separated from the friction layer 12, a potential difference is formed between the first metal electrode and the second metal electrode on the first plate 2. Multiple parallel second metal electrodes and multiple parallel first metal electrodes are connected to a load R via an external wire. Electrons flow from the first metal electrode to the second metal electrode, generating current, forming currents i1 and i2. The total current passing through the external circuit is i=i1+i2. The second plate 5 moves downward until the first metal electrode and the friction layer 12 come into contact. Charge transfer occurs at the contact portion, causing the surface of the first metal electrode to carry a positive charge and the surface of the friction layer 12 to carry an equal amount of negative charge. When the first metal electrode and the friction layer 12 are separated, electrons flow from the second metal electrode to the first metal electrode, generating a reverse current, forming currents i3 and i4. The total current passing through the external circuit is i=i3+i4, and the cycle repeats.

[0052] At the same time, when the entire friction nano and electromagnetic composite energy harvesting device vibrates up and down, the second magnet 4 and the coil 7 undergo relative displacement, and the coil 7 cuts the magnetic flux lines of the second magnet 4 to generate current.

[0053] The energy harvesting process of the interdigitated laminated friction nano-vibration energy harvesting unit produces a frequency-up and frequency-down effect on the electromagnetic vibration energy harvesting unit. When the second plate 5 on the second magnet 4 collides with the first plate 2 on the box 6, the vibration frequency of the second magnet 4 is increased, and then the frequency of the coil 7 cutting the magnetic flux lines is increased, thereby achieving the effect of frequency-up and frequency-down, and increasing the electrical energy output of electromagnetic power generation.

[0054] Obviously, the above embodiments are merely examples for clarity of explanation and are not intended to limit the implementation methods. Those skilled in the art will appreciate that other variations or modifications can be made based on the above description. It is not necessary and impossible to enumerate all implementation methods here. Obvious variations or modifications derived therefrom remain within the scope of protection of the present invention.

Claims

1. A tribo-nano and electromagnetic composite energy harvesting device, characterized in that: include: A box body (6) having a cavity with an open top; a plurality of first plates (2) spaced apart are horizontally arranged on the inner side wall of the box body (6); A first magnet (10) is disposed on the bottom wall of the box (6), with the first magnetic pole of the first magnet (10) facing upward; The second magnet (4) is arranged above the first magnet (10), and the second magnetic pole of the second magnet (4) is arranged downward, the first magnetic pole and the second magnetic pole are mutually repelling magnetic poles, and the second magnet (4) is in a suspended state; a plurality of spaced second plates (5) are horizontally arranged on the periphery of the second magnet (4); a plurality of the first plates (2) and a plurality of the second plates (5) are arranged in an interdigitated manner; and a friction layer (12) is provided on the surface of the second plate (5) opposite to the first plate (2), and a metal electrode (11) is provided on the surface of the first plate (2) opposite to the second plate (5), and the second plate (5) is suitable for contacting, colliding with, and separating from the first plate (2) under a vibration environment; A cover (1) adapted to close the top opening of the box (6); The coil (7) is arranged on the bottom surface of the cover (1), and the coil (7) is located above the second magnet (4).

2. The tribo-nano and electromagnetic composite energy harvesting device according to claim 1, characterized in that: The electronegativity of the friction layer (12) is greater than the electronegativity of the metal electrode (11); and the coil (7), the first plate (2) and the second plate (5) are suitable for jointly obtaining electrical energy under a vibration environment.

3. The tribo-nano and electromagnetic composite energy harvesting device according to claim 2, characterized in that: In the initial state, a gap is provided between the first plate (2) and the second plate (5); the initial state is a state when the friction nano and electromagnetic composite energy harvesting device does not vibrate.

4. The tribo-nano and electromagnetic composite energy harvesting device according to claim 1, characterized in that: The coil (7) is fixed to the bottom surface of the cover body (1) via a detachable fastener.

5. The tribo-nano and electromagnetic composite energy harvesting device according to claim 1, characterized in that: A groove is provided on the bottom wall of the box body (6), and the first magnet (10) is located in the groove.

6. The tribo-nano and electromagnetic composite energy harvesting device according to claim 5, characterized in that: Also includes: The guide shaft (3) is vertically arranged in the box body (6), the bottom end of the guide shaft (3) is located in the groove of the box body (6), and the guide shaft (3) and the box body (6) are made as one body; and the first magnet (10) and the second magnet (4) are both sleeved on the guide shaft (3).

7. The tribo-nano and electromagnetic composite energy harvesting device according to claim 6, characterized in that: The coil (7), the first magnet (10), and the second magnet (4) are all coaxially arranged.

8. The tribo-nano and electromagnetic composite energy harvesting device according to claim 6, characterized in that: The top end of the guide shaft (3) is located in the circular hole of the coil (7).

9. The tribo-nano and electromagnetic composite energy harvesting device according to any one of claims 1 to 5, characterized in that: The metal electrodes (11) include: a plurality of first metal electrodes arranged on the top surface of the first plate (2) and a plurality of second metal electrodes arranged on the bottom surface of the first plate (2); the plurality of first metal electrodes are arranged in parallel via a first wire; and the plurality of second metal electrodes are arranged in parallel via a second wire, thereby realizing interdigital output of the first metal electrodes and the second metal electrodes.

10. The tribo-nano and electromagnetic composite energy harvesting device according to any one of claims 1 to 5, characterized in that: The upper and lower adjacent first plate members (2) and second plate members (5) are arranged at the same interval.

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