Relative rotation type friction nanometer generator

Abstract

The invention discloses a relative rotation type friction nanometer generator which comprises a center shaft rod, an outer cylinder and an inner cylinder, the center shaft rod is sleeved with the outer cylinder and the inner cylinder, and the inner cylinder is located in the outer cylinder. Friction power generation parts are arranged on the outer wall of the inner cylinder and the inner wall of the outer cylinder; the inner cylinder is fixedly connected with the center shaft rod, the outer cylinder is fixedly connected with the center shaft rod in a one-way mode, and one end of the center shaft rod is fixedly connected with a driving part in a one-way mode. By utilizing the characteristic that the first one-way bearing, the second one-way bearing and the third one-way bearing can only rotate in a certain specific direction and can be locked in another opposite direction, various external vibration energy can be firstly converted into gravitational potential energy of the second mass block and the third mass block, and then the gravitational potential energy is automatically released into kinetic energy; and the friction nanometer generator is driven to generate electric output with a certain rule.

Description

Technical Field

[0001] The invention relates to the technical field of friction generators, in particular to a relatively rotating friction nanogenerator. Background Art

[0002] With the rapid development of the global economy, energy shortage and environmental pollution caused by the long-term use of traditional fossil energy such as coal and oil are two urgent problems that need to be solved. The ocean accounts for about 71% of the earth's surface and contains rich, clean, renewable energy, including water wave energy and tidal energy. It is of great significance to collect and utilize this energy to meet the power needs of infrastructure. Traditional electromagnetic generators are greatly limited in the field of water wave energy collection due to their high required frequency and fast speed. They often require expensive fixed devices to adapt to specific environments, and the energy conversion efficiency is very low, especially at low frequencies.

[0003] Faced with the vast ocean energy, in view of its low-frequency, irregular, and distributed energy characteristics, the friction nanogenerator, as a new type of mechanical energy harvesting technology, has the characteristics of low frequency, high efficiency, and a wide range of material selection, and is widely used in the collection of ocean energy. Based on the coupling effect of contact electrification and electrostatic induction, the disordered mechanical energy in the environment can be effectively converted into electrical energy. When two friction materials with different electronegativity come into contact, charge transfer occurs between the two friction materials due to the friction electrification effect, so a potential difference is formed between the two; in the external circuit, the electrons will flow on the electrodes driven by the potential difference to balance the potential difference, which is manifested as the generation of electrical signals in the external circuit. In addition, the friction nanogenerator composed of polymer films, porous materials, and metal electrodes has the advantages of light weight and low cost. Therefore, the floating water wave power station constructed by the friction nanogenerator grid is considered to be one of the most promising low-cost water wave energy harvesting technologies.

[0004] In order to further promote the application of friction nanogenerators in the field of wave energy collection, many researchers have proposed various cylindrical friction nanogenerators and conducted systematic research. In 2021, the literature [Adv.Funct.Mater.2021,31,2106398] reported a friction nanogenerator based on a segmented swing structure. The introduction of soft and dense rabbit hair reduced friction resistance and material wear, and the design and optimization of the segmented structure further improved the output performance of the friction nanogenerator. However, this segmented swing structure can only effectively collect water wave energy of lower frequencies (0.8-1.4Hz). For low-frequency water waves above 1.4Hz, its collection efficiency is far less than that of a rotary friction nanogenerator. In 2022, the literature [Adv.Energy Mater.2022,2203219] reported a friction nanogenerator with a unidirectional rotating cylindrical wave-driven linkage mechanism. On the basis of citing soft and dense rabbit hair, a unidirectional bearing was added, so that the friction nanogenerator can convert the swing energy in the environment into the unidirectional rotation energy of the rotor. The rabbit hair on the rotor in the swing mode does not have enough time to change the direction of movement, thus generating a large friction resistance during the movement. Therefore, there is no effective relative position change between the triboelectric materials, resulting in a decrease in the output performance of the device. When the ordinary bearing at the center of the rotor is replaced by a one-way bearing, the rotor rotates in one direction under the action of the central axis. An effective relative displacement is generated between the rabbit hair and the friction film, and a relatively high output can be obtained. For the rotation mode, in order to effectively obtain water wave energy. Although the rotary friction nanogenerator using a one-way bearing designed in the latest research work can effectively collect wave energy in the environment, the design of its mechanical structure can only utilize half of the swing kinetic energy and cause a waste of the other half of the swing kinetic energy. Summary of the invention

[0005] The purpose of the present invention is to provide a relatively rotating friction nanogenerator to solve the problems raised in the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A relatively rotating friction nanogenerator comprises a central shaft, an outer cylinder and an inner cylinder sleeved on the central shaft, wherein the inner cylinder is located inside the outer cylinder;

[0008] The outer wall of the inner cylinder and the inner wall of the outer cylinder are provided with a friction power generation unit;

[0009] The inner cylinder is fixedly connected to the central shaft, the outer cylinder is unidirectionally fixedly connected to the central shaft, one end of the central shaft is unidirectionally fixedly connected to a driving part, the driving part is unidirectionally poweredly connected to the outer cylinder, the unidirectional driving direction of the outer cylinder and the driving part is a forward direction, and the unidirectional fixing direction of the outer cylinder and the central shaft and the unidirectional fixing direction of the central shaft and the driving part are both reverse directions.

[0010] As a further solution of the present invention: the friction power generation unit includes an electrode array located on the inner wall of the outer cylinder, flexible blades and a sheet-like film array located on the outer wall of the inner cylinder.

[0011] As a further solution of the present invention: the sheet-like film array includes a first friction unit and a second friction unit, the first friction units and the second friction units are the same in number and arranged at intervals, and the flexible blade is in frictional contact with the first friction unit and the second friction unit.

[0012] As a further solution of the present invention: the outer cylinder includes a cylinder body and a first outer cylinder cover plate and a second outer cylinder cover plate arranged at two ends of the cylinder body.

[0013] As a further solution of the present invention: the first outer cylindrical cover plate is fixedly connected to the central shaft in one direction through a first one-way bearing, the first one-way bearing is connected to the central shaft through a first coupling, and the second outer cylindrical cover plate is freely rotatably connected to the central shaft through a two-way bearing.

[0014] As a further solution of the present invention: the driving part includes a sector plate, and the sector plate is fixedly connected to the central shaft in one direction through a third coupling and a third one-way bearing.

[0015] As a further solution of the present invention: a second one-way bearing is connected to a side of the third coupling close to the second outer cylindrical cover plate, a second coupling is sleeved on the second one-way bearing, and the second coupling is fixedly connected to the second outer cylindrical cover plate.

[0016] As a further solution of the present invention: a first mass block is fixedly connected to the sector plate.

[0017] As a further solution of the present invention: the outer wall of the outer cylinder is provided with a third mass block, the inner wall of the inner cylinder is provided with a second mass block, the inner cylinder includes an inner cylinder body and an inner cylinder cover plate arranged at both ends of the inner cylinder body, and the inner cylinder cover plate is fixedly connected to the central shaft.

[0018] As a further solution of the present invention: the central axis is placed on a support frame, the support frame includes a base and a first bracket and a second bracket arranged on the base, and the central axis is rotatably connected to the first bracket and the second bracket.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The present invention adds a gravitational potential energy storage device based on the third mass block on the basis of the one-way bearing compound pendulum structure. By utilizing the characteristics that the first one-way bearing, the second one-way bearing and the third one-way bearing can only rotate in a certain direction and are locked in the other opposite direction, various external vibration energies can be first converted into the gravitational potential energy of the second mass block and the third mass block, and then automatically released as kinetic energy, driving the friction nanogenerator to generate electrical output with a certain pattern.

[0021] 2. If the external vibration excitation intensity is very small, the present invention can intermittently convert the vibration energy into the gravitational potential energy of the second mass block and the third mass block. After the second mass block and the third mass block reach the highest point, the gravitational potential energy is automatically released and converted into kinetic energy, and the inner cylinder and the outer cylinder keep performing relative rotational motion, driving the friction nanogenerator to work.

[0022] 3. If the external vibration intensity is large, the present invention can quickly convert the external vibration energy into the gravitational potential energy of the second mass block and the third mass block, and then release it quickly. The inner cylinder and the outer cylinder keep performing relative rotational motion to drive the friction nanogenerator to work.

[0023] 4. The present invention can collect external vibration energy of various intensities and convert it into the gravitational potential energy of the second mass block and the third mass block, so as to promote the inner cylinder and the outer cylinder to rotate relative to each other continuously, thereby making the maximum use of external vibration energy, greatly improving the output performance of the friction nanogenerator and broadening the scope of application. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a side view of the relative rotary friction nanogenerator of this embodiment without the bracket;

[0025] Figure 2 Schematic diagram of the spindle and the swing rotation module in this embodiment;

[0026] Figure 3 Schematic diagram of the structure of the bracket of this embodiment;

[0027] Figure 4 Schematic diagram of the three-dimensional structure of the outer cylinder in this embodiment;

[0028] Figure 5 An exploded view of the connection structure between the first outer cylindrical cover plate, the first one-way bearing and the first bearing coupling of this embodiment;

[0029] Figure 6It is a structural schematic diagram of the second outer cylindrical cover plate and the bidirectional bearing connection and the swing structure (including the second bearing, the second bearing coupling, the third one-way bearing, the third one-way bearing coupling, the compound pendulum, and the first mass block) of this embodiment;

[0030] Figure 7 Schematic diagram of the three-dimensional structure of the inner cylinder of this embodiment;

[0031] Figure 8 Schematic diagram of the three-dimensional structure of the inner cylinder cover plate of this embodiment;

[0032] Fig. 9 Schematic diagram of the motion state of the first mass block, the inner cylinder and the outer cylinder in this embodiment.

[0033] In the figure: 1-outer cylinder, 2-inner cylinder, 3-central shaft, 4-first one-way bearing, 5-first mass block, 6-second one-way bearing, 7-third one-way bearing, 8-flexible blades, 9-electrode array, 10-sheet film array, 11-outer cylinder, 12-first outer cylinder cover plate, 13-second outer cylinder cover plate, 14-second mass block, 15-third mass block, 16-first coupling, 17-second coupling, 18-third coupling, 19-first bracket, 20-second bracket, 21-inner cylinder, 22-inner cylinder cover plate, 23-mounting hole, 101-first friction unit, 102-second friction unit, 100-fan plate, 200-bidirectional bearing. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0035] See also Figure 1-9 In an embodiment of the present invention, a relatively rotating friction nanogenerator includes a central shaft 3 and an outer cylinder 1 and an inner cylinder 2 sleeved on the central shaft 3, wherein the inner cylinder 2 is located inside the outer cylinder 1. In this embodiment, the central shaft 3 has a diameter of 8 mm and a length of 225 mm and is made of acrylic material.

[0036] The outer wall of the inner cylinder 2 and the inner wall of the outer cylinder 1 are provided with a friction power generation unit, which includes an electrode array 9 located on the inner wall of the outer cylinder 1, a flexible blade 8, and a first friction unit 101 and a second friction unit 102 located on the outer wall of the inner cylinder 2. The first friction units 101 and the second friction units 102 are the same in number and arranged at intervals. The flexible blade 8 is in friction contact with the first friction unit 101 and the second friction unit 102. In this embodiment, the electrode array 9 is composed of twenty-eight rectangular copper foils, and the length and width of a single copper foil are 85 mm and 10 mm respectively; two flexible leaves are also pasted on the inner surface of the outer cylinder 1. The sheet 8, the flexible blade is made of a rectangular film, the length and width of the rectangular film are 75mm and 5mm respectively, the thickness is 30μm, and it is made of FEP film material; the outer surface of the inner cylinder 21 is pasted with a sheet film array 10, which is composed of sixteen first friction units 101 and sixteen second friction units 102 arranged alternately, the first friction unit 101 is made of FEP film, and the second friction unit 102 is made of nylon 66 film; the first friction unit 101 and the second friction unit 102 have the same size, which is 75mm long, 10mm wide, and 25μm thick. The gap between the sheet film array 10 and the electrode array 9 is about 1mm.

[0037] The inner cylinder 2 is fixedly connected to the central shaft 3, the outer cylinder 1 is unidirectionally fixedly connected to the central shaft 3, one end of the central shaft 3 is unidirectionally fixedly connected to a driving part, the driving part is unidirectionally poweredly connected to the outer cylinder 1, the unidirectional driving direction of the outer cylinder 1 and the driving part is the forward direction, and the unidirectional fixing direction of the outer cylinder 1 and the central shaft 3 and the unidirectional fixing direction of the central shaft 3 and the driving part are both reverse directions.

[0038] In this embodiment, the outer cylinder 1 includes a cylinder body 11 and a first outer cylinder cover plate 12 and a second outer cylinder cover plate 13 arranged at both ends of the cylinder body 11. The outer cylinder body 11 has a thickness of 3 mm, an outer diameter of 100 mm, and a height of 94 mm. It is made of acrylic material. A groove is opened at the center of the first outer cylinder cover plate 12. The groove has a depth of 5 mm and a diameter of 16 mm. The first outer cylinder cover plate 12 is fixedly connected to the central shaft rod 3 in one direction through a first one-way bearing 4. The first one-way bearing 4 is connected to the central shaft rod 3 through a first coupling 16. The first one-way bearing 4 has a thickness of 5 mm, an inner diameter of 8 mm, and an outer diameter of 16 mm. The first one-way bearing 4 is embedded in the groove in the center of the first outer cylinder cover plate 12. The first coupling 16 is made of acrylic material, and the outer diameter of the small cylinder on the left side is 12 mm, and the inner diameter of the large cylinder on the right side is 22 mm. The second outer cylinder cover plate 13 is freely rotatably connected to the central shaft rod 3 through a two-way bearing 200.

[0039] The inner cylinder 2 includes an inner cylinder body 21 and inner cylinder cover plates 22 arranged at both ends of the inner cylinder body 21. The inner cylinder cover plates 22 are fixedly connected to the central shaft rod 3. The inner cylinder body 21 has a thickness of 3 mm, an outer diameter of 85 mm, and a height of 75 mm, and is made of acrylic material.

[0040] The driving part includes a fan-shaped plate 100, on which a first mass block 5 is fixedly connected. The fan-shaped plate has a thickness of 5 mm and a pendulum length of 65 mm and is made of acrylic material. The first mass block 5 has a mass of 250 g and is made of metal lead. The fan-shaped plate 100 is fixedly connected to the central shaft 3 in one direction through a third coupling 18 and a third one-way bearing 7. The third coupling 18 is connected to a second one-way bearing 6 on the side close to the second outer cylindrical cover plate 13. The second one-way bearing 6 is sleeved with a second coupling 17. The second coupling 17 is fixedly connected to the second outer cylindrical cover plate 13. The inner diameter of the second coupling 17 is 32 mm, and the inner diameter of the second one-way bearing 6 is 12 mm and the outer diameter is 32 mm. The bidirectional bearing 200 is embedded in the groove in the center of the second outer cylindrical cover plate 13.

[0041] The outer wall of the outer cylinder 1 is provided with a third mass block 15, and the inner wall of the inner cylinder 2 is provided with a second mass block 14. The second mass block 14 is fixed to one side of the inner cylinder body 21. The mass of the second mass block 14 is 50g and is made of metal lead material.

[0042] The central axis 3 is placed on the support frame, and the support frame includes a base and a first bracket 19 and a second bracket 20 arranged on the base. The central axis 3 is rotatably connected to the first bracket 19 and the second bracket 20. In this embodiment, the support frame is made of a first bracket 19 and a second bracket 20 with a length of 230 mm and a width of 50 mm and two first brackets 19 and a length of 90 mm and a width of 40 mm. Holes with diameters of 32 mm and 22 mm are dug at equal heights of the first bracket 19 and the second bracket 20, respectively, and the brackets are made of acrylic material.

[0043] When the present invention is used, the present invention is mainly used to convert the widely existing vibration energy into electrical energy. To illustrate the working principle of the present generator, it is assumed that the first one-way bearing 4 can rotate freely in the counterclockwise direction and is locked in the clockwise direction; the second one-way bearing 6 can rotate freely in the clockwise direction and is locked in the counterclockwise direction; the third one-way bearing 7 can rotate freely in the counterclockwise direction and is locked in the clockwise direction. When in use, first fix the position of the bracket, then the external vibration mechanical energy acts on the first mass block 5, and under the action of the external vibration, the first mass block 5 drives the fan-shaped plate 100 to swing back and forth. When the fan plate 100 swings clockwise, under the action of the third one-way bearing 7, the central shaft 3 rotates unidirectionally (clockwise) with the swing of the fan plate 100. Since the inner cylinder 2 is fixedly connected to the central shaft 3, during the swing of the fan plate 100, the central shaft 3 drives the inner cylinder 2 to rotate unidirectionally clockwise, and the center of gravity of the second mass block 14 on the inner cylinder 2 slowly rises with the swing of the fan plate 100. Under the action of the first one-way bearing 4, the center of gravity of the second mass block 14 will not fall back. When the center of gravity of the second mass block 14 rises and passes the highest point, the second mass block 14 drives the inner cylinder 2 to rotate and fall rapidly under the action of gravity. When the sector plate 100 swings counterclockwise, the third one-way bearing 7 rotates freely, and the third coupling 18 drives the second one-way bearing 6 to rotate counterclockwise. Since the outer cylinder is fixedly connected to the second coupling 17, during the swinging of the sector plate 100, the second one-way bearing 6 drives the outer cylinder 1 to rotate counterclockwise in one direction through the second coupling 17. The center of gravity of the third mass block 15 on the outer cylinder 1 slowly rises with the swinging of the sector plate 100. Under the action of the first bracket 19 and the second bracket 20, the center of gravity of the third mass block 15 will not fall back. When the center of gravity of the third mass block 15 rises and passes the highest point, the third mass block 15 drives the outer cylinder 1 to rotate and fall rapidly under the action of gravity.

[0044] Since the flexible blade 8 is fixed on the inner surface of the outer cylinder, during the rotation of the inner cylinder, the flexible blade 8 rubs back and forth with the first friction unit 101 and the second friction unit 102. Since the electron-acquiring ability of the flexible blade 8 is greater than that of the second friction unit 102, when the flexible blade and the second friction unit rub, the flexible blade is negatively charged and the second friction unit is positively charged; since the electron-acquiring ability of the flexible blade 8 is less than or equal to the first friction unit 101, when the flexible blade and the first friction unit rub, the electrons on the flexible blade will be transferred to the first friction unit, making the first friction unit negatively charged; therefore, there will be a potential difference between the first friction unit and the second friction unit. Since the electrode array 9 is very close to the sheet-like film array 10, electrostatic induction causes a potential difference between the first electrode and the second electrode. If the first electrode and the second electrode are connected through an external circuit to form a path, an alternating current will flow through the external circuit.

[0045] The relative rotation type friction nanogenerator provided by the present invention can convert external vibration energy into the bidirectional swing of the fan-shaped plate, and then drive the inner and outer cylinders to rotate relative to each other, thereby converting kinetic energy into double force potential energy and storing it, and then converting gravitational potential energy into electrical energy. The unique swing-double rotation mechanism can effectively collect external vibration energy, and the double force potential energy storage and release function can improve the output current size and stability of the friction nanogenerator, so it has a wide range of application prospects.

[0046] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0047] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A relatively rotating friction nanogenerator, comprising a central shaft (3) and an outer cylinder (1) and an inner cylinder (2) sleeved on the central shaft (3), characterized in that: The inner cylinder (2) is located inside the outer cylinder (1); A friction power generation unit is provided on the outer wall of the inner cylinder (2) and the inner wall of the outer cylinder (1); The inner cylinder (2) is fixedly connected to the central shaft (3), the outer cylinder (1) is unidirectionally fixedly connected to the central shaft (3), one end of the central shaft (3) is unidirectionally fixedly connected to a driving unit, the driving unit is unidirectionally dynamically connected to the outer cylinder (1), the unidirectional driving direction of the outer cylinder (1) and the driving unit is a forward direction, and the unidirectional fixing direction of the outer cylinder (1) and the central shaft (3) and the unidirectional fixing direction of the central shaft (3) and the driving unit are both reverse directions.

2. The relative rotation friction nanogenerator according to claim 1, characterized in that: The friction power generation unit comprises an electrode array (9) located on the inner wall of the outer cylinder (1), a flexible blade (8), and a sheet-like film array (10) located on the outer wall of the inner cylinder (2).

3. The relative rotation friction nanogenerator according to claim 2, characterized in that: The sheet-like film array (10) comprises a first friction unit (101) and a second friction unit (102); the first friction units (101) and the second friction units (102) are of the same number and are arranged at intervals; the flexible blade (8) is in frictional contact with the first friction unit (101) and the second friction unit (102).

4. The relative rotation friction nanogenerator according to claim 1, characterized in that: The outer cylinder (1) comprises a cylinder body (11) and a first outer cylinder cover plate (12) and a second outer cylinder cover plate (13) arranged at two ends of the cylinder body (11).

5. The relative rotation friction nanogenerator according to claim 4, characterized in that: The first outer cylindrical cover plate (12) is fixedly connected to the central shaft (3) in one direction via a first one-way bearing (4), the first one-way bearing (4) is connected to the central shaft (3) via a first coupling (16), and the second outer cylindrical cover plate (13) is freely rotatably connected to the central shaft (3) via a two-way bearing (200).

6. The relative rotation friction nanogenerator according to claim 4, characterized in that: The driving part comprises a sector plate (100), and the sector plate (100) is fixedly connected to the central shaft (3) in one direction through a third coupling (18) and a third one-way bearing (7).

7. The relative rotation friction nanogenerator according to claim 6, characterized in that: A second one-way bearing (6) is connected to the side of the third coupling (18) close to the second outer cylindrical cover plate (13); a second coupling (17) is sleeved on the second one-way bearing (6); and the second coupling (17) is fixedly connected to the second outer cylindrical cover plate (13).

8. The relative rotation friction nanogenerator according to claim 6, characterized in that: A first mass block (5) is fixedly connected to the sector plate (100).

9. The relative rotation friction nanogenerator according to claim 1, characterized in that: The outer wall of the outer cylinder (1) is provided with a third mass block (15), the inner wall of the inner cylinder (2) is provided with a second mass block (14), the inner cylinder (2) comprises an inner cylinder body (21) and inner cylinder cover plates (22) arranged at both ends of the inner cylinder body (21), and the inner cylinder cover plates (22) are fixedly connected to the central shaft (3).

10. The relative rotation friction nanogenerator according to claim 1, characterized in that: The central shaft (3) is placed on a support frame, and the support frame comprises a base and a first bracket (19) and a second bracket (20) arranged on the base. The central shaft (3) is rotatably connected to the first bracket (19) and the second bracket (20).

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