A bionic ultra-low rotation-ejection piezoelectric vibration energy harvesting device

Abstract

The present invention relates to the field of micro-nano energy devices, and discloses a bionic ultra-low rotation-ejection piezoelectric vibration energy harvesting device, comprising: a housing; a rotating member rotatably connected within the housing, the rotating member having a plurality of branches, and the plurality of branches being evenly distributed in the circumferential direction of the rotating member; a transmission part slidably connected to the side of the rotating member within the housing, an elastic member being respectively connected to the housing and the transmission part, a push rod being provided on the transmission part, a part of the push rod passing through the housing, and a first magnet being provided at the passing-through end of the push rod; a piezoelectric cantilever beam longitudinally arranged on the side of the passing-through end of the push rod outside the housing, a second magnet being provided on the piezoelectric cantilever beam opposite to the first magnet, and the magnetic poles of the opposite ends of the first magnet and the second magnet being the same; this bionic ultra-low rotation-ejection piezoelectric vibration energy harvesting device can convert broadband and ultra-wideband mechanical vibrations into instantaneous high-energy output in a non-linear manner at low rotational speeds, flexibly adapt to diverse vibration source environments, and maximize the energy collection efficiency.

Description

Technical Field

[0001] The invention relates to the field of micro-nano energy devices, and in particular to a bionic ultra-low rotation-ejection piezoelectric vibration energy capture device. Background Art

[0002] Piezoelectric vibration energy harvester is a new type of micro-nano energy device that can capture vibration energy in the environment and convert it into electrical energy, replacing batteries to self-power low-power wireless electronic products (such as wireless sensor nodes). Currently, a large number of low-power wireless sensor nodes are deployed in rotating equipment, such as wind turbine blades, rotor blades, machine tool shafts, aircraft engines, automobile tires, and high-speed rail wheels and rails, for online health monitoring and operation control of equipment and structures. However, how to continuously self-power a large number of low-power sensors in rotating equipment is a potential challenge.

[0003] Existing piezoelectric vibration harvesters are difficult to adapt to the complex and changeable vibration spectrum in the actual environment. Especially when the rotation speed is low, the piezoelectric vibration harvester makes a small-amplitude monostable vibration, which greatly reduces the output of the piezoelectric vibration harvester. At present, the minimum effective speed of the rotational vibration harvester is usually around 100 rpm. Limited by the structure and frequency characteristics of the rotational vibration harvester, there is still a large gap in the collection and conversion of ultra-low (less than 60rpm) rotational vibration energy, which needs further development and utilization. Summary of the invention

[0004] The present invention proposes a bionic ultra-low rotation-ejection piezoelectric vibration energy capture device to solve the deficiencies in the above-mentioned prior art. The bionic ultra-low rotation-ejection piezoelectric vibration energy capture device can convert broadband and ultra-wideband mechanical vibrations into instantaneous high-energy output in a nonlinear manner at low rotation speed, flexibly adapt to a variety of vibration source environments, and maximize the energy collection efficiency.

[0005] The technical solution of the present invention is: a bionic ultra-low rotation-ejection piezoelectric vibration energy capture device, comprising:

[0006] The housing is used to provide packaging space for the rotating part 2 and the transmission part 3 of the device;

[0007] The rotating member is rotatably connected in the housing, and the rotating member has a plurality of branches, and the plurality of branches are evenly distributed in the circumference of the rotating member;

[0008] The transmission member comprises: a transmission part, an elastic member and a push rod, wherein the transmission part is slidably connected to the side of the rotating member in the housing, the elastic member is respectively connected to the housing and the transmission part, the elastic member is used to provide resistance to the movement of the transmission part away from the rotating member, the push rod is arranged on the transmission part, a part of the push rod passes through the housing, and a first magnet is arranged at the passing end of the push rod;

[0009] The piezoelectric cantilever beam is longitudinally arranged on the side of the end of the push rod outside the shell, and a second magnet opposite to the first magnet is provided near the end of the piezoelectric cantilever beam. The magnetic poles of the opposite ends of the first magnet and the second magnet are the same. When the first magnet is driven by the push rod to move toward the second magnet, the second magnet drives the piezoelectric cantilever beam to bend.

[0010] In at least one embodiment of the present invention, a first pulley is provided at the end of each of the multiple branches on the rotating member, the transmission part has a bending part, and second pulleys abutting against the shell are provided at both ends of the transmission part, the bending position of the transmission part is arc-shaped, and the first pulley is used to abut against the bending part of the transmission part.

[0011] In at least one embodiment of the present invention, a slide seat is provided on the shell, and the push rod is slidably connected to the slide seat; the slide seat provides a guide for the push rod and ensures that the push rod can always maintain horizontal movement.

[0012] In at least one embodiment of the present invention, a first cylinder is provided at a position of the transmission part away from the push rod, a second cylinder is provided at a position of the shell relative to the first cylinder, and the elastic member is a spring, and the elastic member is mounted on the first cylinder and the second cylinder.

[0013] In at least one embodiment of the present invention, the elastic member and the push rod are located at the same horizontal height to ensure that the elastic force of the elastic member can be directly transmitted to the push rod, thereby ensuring that the push rod can stably perform horizontal movement.

[0014] In at least one embodiment of the present invention, the shell includes: a semicircular chamber and a rectangular chamber, the semicircular chamber and the rectangular chamber are connected, the rotating member is rotatably connected in the semicircular chamber, and the transmission part is slidably connected in the rectangular chamber.

[0015] In at least one embodiment of the present invention, a fixing seat is provided on the outer wall of the semicircular chamber, and the piezoelectric cantilever beam is arranged on the fixing seat so that the device has an integrated structure.

[0016] In at least one embodiment of the present invention, the first magnet and the second magnet are both in the shape of a cuboid, and the first magnet and the second magnet are equal in size.

[0017] In at least one embodiment of the present invention, the piezoelectric cantilever beam includes: a metal substrate, a first piezoelectric ceramic and a second piezoelectric ceramic, wherein the first piezoelectric ceramic and the second piezoelectric ceramic are respectively arranged on two surfaces of the metal substrate, and the first piezoelectric ceramic and the second piezoelectric ceramic are equal in size and have opposite polarization directions.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] The present invention provides a bionic ultra-low rotation-ejection piezoelectric vibration energy harvesting device. When in use, when the rotating member is excited by external environmental vibration to rotate, the branch of the rotating member contacts the transmission part, causing the transmission part to be compressed, and then conducting the compression force to the elastic member. When the branch of the rotating member leaves the transmission part, the elastic member releases energy, pushes the first magnet to move through the push rod, causing the repulsive force of the first magnet on the second magnet to change, and the piezoelectric cantilever beam generates bending vibration in the vertical plane to generate charges and output to form a current, achieving the purpose of converting mechanical vibration energy into electrical energy and realizing the accumulation and controllable release of ultra-low frequency vibration energy.

[0020] Through the structure formed by the transmission member and the piezoelectric cantilever beam oscillator, the present invention can convert broadband and ultra-wideband mechanical vibrations into instantaneous high-energy output in a non-linear manner at low rotational speeds by using the rotational energy storage and ejection mechanism, flexibly adapting to diverse vibration source environments and maximizing the energy collection efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a front view structural schematic diagram of the present invention.

[0022] Figure 2 It is a side view structural schematic diagram of the present invention.

[0023] Figure 3 It is a side view of the piezoelectric cantilever beam of the present invention.

[0024] Figure 4 It is a front view of the piezoelectric cantilever beam of the present invention.

[0025] Figure 5 It is a side view of the conduction connecting rod of the present invention.

[0026] Figure 6 It is the voltage output characteristic of the present invention at a rotational speed of 30 rpm.

[0027] Figure 7 It is the voltage output characteristic of the present invention at a rotational speed of 60 rpm.

[0028] DESCRIPTION OF REFERENCE NUMERALS:

[0029] 1. Housing; 11. Semi-circular chamber; 12. Rectangular chamber; 13. Fixed seat; 2. Rotating member; 21. Branch; 211. First pulley; 3. Transmission member; 31. Transmission part; 311. Second pulley; 32. Elastic member; 321. First cylinder; 322. Second cylinder; 33. Push rod; 331. First magnet; 332. Slide seat; 4. Piezoelectric cantilever beam; 41. Second magnet. DETAILED DESCRIPTION OF THE INVENTION

[0030] The attached drawings in the present invention are not strictly drawn according to the actual scale, and the specific sizes and quantities of each structure can be determined according to actual needs. The attached drawings described in the present invention are only schematic diagrams of the structures.

[0031] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the attached drawings of the embodiments of the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0032] Unless otherwise defined, the technical terms or scientific terms used herein shall have the ordinary meanings as understood by those of ordinary skill in the art to which the present invention pertains. The "first", "second" and similar terms used in the present invention do not denote any order, quantity or importance, but are only used to distinguish different components. The terms such as "comprising" or "including" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. The terms such as "inside", "outside", "above", "below", "far", "near", "front", "rear", etc. are only used to indicate relative positional relationships. When the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0033] By mimicking the mechanism of the bursting and catapulting of pods in nature, the bionic structure provides a unique way of energy storage and release, effectively overcoming the limitations of traditional piezoelectric vibration energy harvesting systems under narrow frequency band restrictions. The phenomenon of pod bursting and catapulting demonstrates the principle in nature of achieving efficient energy conversion through the gradual accumulation and instantaneous release of internal stress. Applying this principle to the structural design of a piezoelectric vibration energy harvester, a bionic ultra-low rotation-catapulting piezoelectric vibration energy harvesting device has been invented.

[0034] The device has the function of rotational energy storage and ejection, which enables the system to convert broadband, low-speed mechanical vibration into instantaneous high energy output in a nonlinear manner, thereby improving the efficiency of energy harvesting. In addition, the bionic structure enables the system to adapt to a variety of vibration source environments more flexibly, and maximizes the energy collection efficiency by optimizing the burst elastic energy release process. At present, the minimum effective speed of the rotational vibration energy harvester is usually around 100 rpm; Shi Ning's team at Anhui University of Technology designed a rotary magnetic nonlinear piezoelectric energy harvester and studied its dynamic characteristics and energy output performance in a rotating environment, mainly for scenes with speeds of 100 rpm and higher. Zhang Feiyang's team at Shanghai University studied the performance of the double-beam nonlinear energy harvester under rotational motion. Experiments show that it has good energy harvesting performance in the range of about 95 rpm to about 353 rpm. When the rotation speed is lower than 95 rpm, the energy harvesting efficiency is significantly reduced. Limited by the structure and frequency characteristics of the rotational vibration energy harvester, there is still a large gap in the collection and conversion of ultra-low (less than 60 rpm) rotational vibration energy, which needs to be further developed and utilized.

[0035] Combination Figures 1 to 5 As shown, a bionic ultra-low rotation-ejection piezoelectric vibration energy capture device comprises:

[0036] The housing 1 is used to provide a packaging cavity for the rotating part 2 and the transmission part 3 of the device.

[0037] The rotating member 2 is rotatably connected in the housing 1, and the rotating member 2 has multiple branches 21, and the multiple branches 21 are evenly distributed in the circumference of the rotating member 2; specifically, the number of the branches 21 is 2 to 4, and preferably, the number of the branches 21 is 3.

[0038] The transmission member 3 includes: a transmission part 31, an elastic member 32 and a push rod 33. The transmission part 31 is slidably connected to the side of the rotating member 2 in the housing 1. The elastic member 32 is connected to the housing 1 and the transmission part 31 respectively. The elastic member 32 is used to provide resistance to the movement of the transmission part 31 away from the rotating member 2. The push rod 33 is arranged on the transmission part 31. A part of the push rod 33 passes through the housing 1. A first magnet 331 is arranged at the passing end of the push rod 33.

[0039] The piezoelectric cantilever beam 4 is longitudinally arranged on the side of the end of the push rod 33 outside the shell 1. A second magnet 41 opposite to the first magnet 331 is provided on the piezoelectric cantilever beam 4 near the end position. The magnetic poles of the opposite ends of the first magnet 331 and the second magnet 41 are the same. When the push rod 33 pushes the first magnet 331 to move horizontally, the second magnet 41 moves due to the repulsive force of the first magnet 331, thereby causing the piezoelectric cantilever beam 4 to bend, resulting in induced charges on the surface of the piezoelectric cantilever beam 4, and output to form current.

[0040] As an alternative embodiment, a first pulley 211 is provided at the end of each of the multiple branches 21 on the rotating member 2. The transmission part 31 has a bent part. Second pulleys 311 in contact with the housing 1 are respectively provided at both ends of the transmission part 31. The bent position of the transmission part 31 is arc-shaped. The first pulley 211 is used to abut against the bent part of the transmission part 31. The bent part of the transmission part 31 is arc-shaped. The arrangement of the first pulley 211 can prevent the branches 21 from having a rigid collision with the transmission part 31, thereby avoiding wear of the branches 21 and excessive loss of energy here.

[0041] As an alternative embodiment, a sliding seat 332 is penetrated through the housing 1, and the push rod 33 is slidably connected to the sliding seat 332; the sliding seat 332 provides a guiding function for the push rod 33 and ensures that the push rod 33 can always maintain a horizontal movement.

[0042] As an alternative embodiment, a first cylinder 321 is provided at a position of the transmission part 31 far from the push rod 33. A second cylinder 322 is provided at a position of the housing 1 opposite to the first cylinder 321. The elastic member 32 is a spring, and the elastic member 32 is sleeved on the first cylinder 321 and the second cylinder 322.

[0043] As an alternative embodiment, the elastic member 32 and the push rod 33 are at the same horizontal height to ensure that the elastic force of the elastic member 32 can be directly transmitted to the push rod 33 and ensure that the push rod 33 can perform a stable horizontal movement.

[0044] As an alternative embodiment, the housing 1 includes: a semi-circular chamber 11 and a rectangular chamber 12. The semi-circular chamber 11 and the rectangular chamber 12 are communicated. The rotating member 2 is rotatably connected in the semi-circular chamber 11, and the transmission part 31 is slidably connected in the rectangular chamber 12; the semi-circular chamber 11 and the rectangular chamber 12 are integrally formed.

[0045] As an alternative embodiment, a fixed seat 13 is provided on the outer wall of the semi-circular chamber 11, and the piezoelectric cantilever beam 4 is provided on the fixed seat 13 to ensure that the device has an integral structure. Specifically, a clamping member is provided on the fixed seat 13, and the piezoelectric cantilever beam 4 is clamped on the fixed seat 13 by the clamping member.

[0046] As an alternative embodiment, both the first magnet 331 and the second magnet 41 are rectangular parallelepipeds, and the first magnet 331 and the second magnet 41 are of equal size to ensure that during the movement of the first magnet 331, the second magnet 41 can receive sufficient and stable repulsive force to drive the piezoelectric cantilever beam 4 completely.

[0047] As an alternative embodiment, the piezoelectric cantilever beam 4 includes a metal substrate, a first piezoelectric ceramic, and a second piezoelectric ceramic. The first piezoelectric ceramic and the second piezoelectric ceramic are respectively disposed on two surfaces of the metal substrate. The first piezoelectric ceramic and the second piezoelectric ceramic are equal in size and opposite in polarization direction.

[0048] The working principle and usage method of this embodiment are as follows:

[0049] The present invention provides a bionic ultra-low rotation-ejection piezoelectric vibration energy harvesting device. When the bionic ultra-low rotation-ejection piezoelectric vibration energy harvesting device is in use, when the rotating member 2 is excited by external environmental vibrations, the rotating member 2 is driven to rotate. After a period of time, multiple first pulleys 211 on the rotating member 2 respectively come into contact with the transmission part 31, causing the transmission part 31 to be compressed. The displacement of the transmission part 31 causes the telescopic elastic member 32 to be compressed, enabling the elastic member 32 to squeeze and store energy. When the multiple first pulleys 211 leave the transmission part 31, the elastic member 32 releases energy, causing the elastic member 32 to displace rapidly. The push rod 33 is used to push the first magnet 331 to move, causing the repulsive force of the first magnet 331 on the second magnet 41 to change, causing the piezoelectric cantilever beam 4 to be affected by non-linear magnetic forces. The piezoelectric cantilever beam 4 generates bending vibrations in the vertical plane, resulting in the generation of induced charges on the surface of the piezoelectric cantilever beam 4 and outputting a formed current; achieving the purpose of converting mechanical vibration energy into electrical energy and realizing the accumulation and controllable release of ultra-low frequency vibration energy.

[0050] Figure 6 Shows the voltage output characteristics of the bionic ultra-low rotation-ejection piezoelectric vibration energy harvesting device at a rotational speed of 30 rpm. It can be seen from the experimental results that the device still exhibits good energy harvesting performance at such a low rotational speed. The maximum output voltage can reach about 4 V, and the average voltage is also stable above 1 V. This result indicates that even under extremely low rotational speed conditions, the device can still effectively convert mechanical energy into electrical energy.

[0051] Figure 7 Further shows the voltage output characteristics of the device at a rotational speed of 60 rpm. The experimental data shows that as the rotational speed increases, the energy harvesting performance is significantly enhanced. The maximum output voltage increases to about 8 V, and the average voltage further increases to above 4 V. This result not only verifies the stability of the device within the low rotational speed range but also indicates that its performance improves significantly as the rotational speed increases.

[0052] The object of the present invention is to achieve a bionic rotary-ejecting piezoelectric vibration energy harvesting device capable of working efficiently under low rotational speed conditions through the innovative structural design of a transmission mechanism and a piezoelectric cantilever oscillator, combined with a rotational energy storage and an ejection mechanism. This device can convert wide-frequency and ultra-wide-frequency mechanical vibrations into instantaneous high-energy output in a non-linear manner, flexibly adapt to diverse vibration source environments, thereby maximizing the energy harvesting efficiency, solving the problem of insufficient output performance of traditional rotary piezoelectric energy harvesters at low rotational speeds, and providing an efficient and reliable solution for the field of low rotational speed energy harvesting.

[0053] The above embodiments are only specific implementation manners of the present invention patent, used to illustrate the technical solutions of the present invention patent, rather than limiting it. The protection scope of the present invention patent is not limited thereto. Although the present invention patent has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: any person skilled in the art within the technical scope disclosed by the present invention can still modify the technical solutions recorded in the foregoing embodiments or can easily think of changes, or perform equivalent replacements on some of the technical features; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions implemented by the present invention patent, and should all be covered within the protection scope of the present invention.

Claims

1. A bionic ultra-low rotation-ejection piezoelectric vibration energy harvesting device, characterized in that Comprising: A housing (1); A rotating member (2), rotatably connected within the housing (1), the rotating member (2) having a plurality of branches (21), and the plurality of branches (21) being evenly distributed in the circumferential direction of the rotating member (2); A transmission member (3), comprising: a transmission portion (31), an elastic member (32), and a push rod (33), the transmission portion (31) being slidably connected to the side of the rotating member (2) within the housing (1), the elastic member (32) being respectively connected to the housing (1) and the transmission portion (31), the elastic member (32) being used to provide resistance to the movement of the transmission portion (31) away from the rotating member (2), the push rod (33) being provided on the transmission portion (31), a part of the push rod (33) passing through the housing (1), and a first magnet (331) being provided at the passing end of the push rod (33); A piezoelectric cantilever beam (4), longitudinally arranged on the side of the passing end of the push rod (33) outside the housing (1), a second magnet (41) being provided at a position near the end of the piezoelectric cantilever beam (4) opposite to the first magnet (331), and the opposite ends of the first magnet (331) and the second magnet (41) having the same magnetic poles.

2. The bionic ultra-low rotation-ejection piezoelectric vibration energy harvesting device according to claim 1, characterized in that, First pulleys (211) are provided at the ends of the plurality of branches (21) on the rotating member (2), the transmission portion (31) has a bent portion, second pulleys (311) respectively abutted against the housing (1) are provided at both ends of the transmission portion (31), the bent position of the transmission portion (31) is arc-shaped, and the first pulleys (211) are used to abut against the bent portion of the transmission portion (31).

3. The biomimetic ultra-low rotation-ejection piezoelectric vibration energy harvesting device according to claim 1, characterized in that, A sliding seat (332) is penetrated through the housing (1), and the push rod (33) is slidably connected to the sliding seat (332).

4. The biomimetic ultra-low rotation-ejection piezoelectric vibration energy harvesting device according to claim 1, wherein A first cylinder (321) is provided at a position of the transmission portion (31) away from the push rod (33), a second cylinder (322) is provided at a position of the housing (1) opposite to the first cylinder (321), the elastic member (32) is a spring, and the elastic member (32) is sleeved on the first cylinder (321) and the second cylinder (322).

5. The bionic ultra-low rotation-ejection piezoelectric vibration energy harvesting device according to claim 4, characterized in that, The elastic member (32) and the push rod (33) are at the same horizontal height.

6. The biomimetic ultra-low rotation-ejection piezoelectric vibration energy harvesting device according to claim 1, wherein, The housing (1) comprises: a semi-circular chamber (11) and a rectangular chamber (12), the semi-circular chamber (11) and the rectangular chamber (12) being communicated with each other, the rotating member (2) being rotatably connected within the semi-circular chamber (11), and the transmission portion (31) being slidably connected within the rectangular chamber (12).

7. The bionic ultra-low rotation-ejection piezoelectric vibration energy harvesting device according to claim 6, characterized in that, A fixing seat (13) is provided on the outer wall of the semi-circular chamber (11), and the piezoelectric cantilever beam (4) is arranged on the fixing seat (13).

8. The biomimetic ultra-low rotation-ejection piezoelectric vibration energy harvesting device according to claim 1, characterized in that, Both the first magnet (331) and the second magnet (41) are cuboid-shaped, and the first magnet (331) and the second magnet (41) are of equal size.

9. The bionic ultra-low rotation-ejection piezoelectric vibration energy harvesting device according to claim 1, wherein, The piezoelectric cantilever beam (4) comprises: a metal substrate, a first piezoelectric ceramic, and a second piezoelectric ceramic, the first piezoelectric ceramic and the second piezoelectric ceramic being respectively arranged on two surfaces of the metal substrate, the first piezoelectric ceramic and the second piezoelectric ceramic being of equal size and having opposite polarization directions.

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