Cantilevered vibration energy harvesting device and sensing device

Abstract

The application relates to a cantilever vibration energy capturing device and a sensing device. The cantilever vibration energy capturing device comprises a base, a piezoelectric component, a first amplification component and a second amplification component. The piezoelectric component comprises a piezoelectric block connected to the base; the first amplification component comprises a moving block and a first connecting rod rotatably connected to the moving block and the piezoelectric block; and the second amplification component comprises a cantilever beam rotatably connected to the base at a first connecting point and connected to the moving block at a second connecting point. When the cantilever beam swings relative to the base, the moving block is driven to move, the moving block stretches or compresses the piezoelectric block through the first connecting rod, and the output power of the cantilever vibration energy capturing device is effectively improved through twice amplification of the force.

Description

Technical Field

[0001] This disclosure pertains to the field of energy harvesting equipment, and in particular to a cantilever vibration energy harvesting device and a sensing device. Background Technology

[0002] With the increasing number of sensor network nodes and their expanding geographical distribution, the power supply problem for wireless sensor nodes is becoming increasingly prominent. Cable power supply is inflexible, costly to build, and difficult to cover large areas. While battery power supply is flexible in deployment and lower in cost, its capacity and lifespan are limited, making frequent battery replacements unsustainable in networked, large-scale monitoring scenarios.

[0003] Energy harvesting technology converts environmental and biological energy, such as solar energy, thermal energy, mechanical energy, and electromagnetic waves, into electrical energy through appropriate methods, providing a sustainable power source for wireless sensing systems, mobile electronic devices, and more. Traditional piezoelectric energy harvesters have low energy harvesting efficiency and low output power, making them unsuitable for some applications. Summary of the Invention

[0004] In view of the above, it is necessary to provide a cantilever vibration energy harvesting device and a sensing device, which aim to improve the output power of the cantilever vibration energy harvesting device.

[0005] Therefore, this disclosure first provides a cantilever vibration energy harvesting device, comprising:

[0006] Base;

[0007] A piezoelectric assembly, including a piezoelectric block connected to the base;

[0008] A first amplification component includes a movable block and a first connecting rod, the first connecting rod being rotatably connected to the movable block and the piezoelectric block;

[0009] The second amplification component includes a cantilever beam, which is rotatably connected to the base at a first connection point and to the movable block at a second connection point;

[0010] When the cantilever beam swings relative to the base, it drives the moving block to move, and the moving block stretches or compresses the piezoelectric block through the first connecting rod.

[0011] According to the cantilever vibration energy harvesting device, the piezoelectric component further includes:

[0012] A pair of connecting blocks are respectively connected to both ends of the piezoelectric block in the stretching direction. The first connecting rod is connected to the connecting blocks, and the piezoelectric block is stretched or compressed through the connecting blocks.

[0013] A pull rod, connected to the connecting block, is used to apply a prestress that compresses the piezoelectric block to the piezoelectric block via the connecting block.

[0014] According to the cantilever vibration energy harvesting device, the piezoelectric block includes a through hole extending in the tensile direction, and the pull rod passes through the through hole to connect a pair of the connecting blocks.

[0015] The cantilever vibration energy harvesting device further includes a support assembly for supporting the piezoelectric block, the support assembly connecting the piezoelectric block and the base.

[0016] According to the cantilever vibration energy harvesting device, the support assembly includes:

[0017] Support block, connected to the base;

[0018] The second connecting rod rotatably connects the support block and the piezoelectric block, and is used to support the piezoelectric block.

[0019] According to the cantilever vibration energy harvesting device, the support assembly includes a support block, and the connecting block is movably connected to the support block along the stretching or compression direction of the piezoelectric block.

[0020] According to the cantilever vibration energy harvesting device, the length of the first connecting rod is greater than the vertical distance from the connection point between the first connecting rod and the piezoelectric block to the moving direction of the moving block;

[0021] When the moving block moves, it pulls the first connecting rod to swing along a vertical direction from the connection point between the first connecting rod and the piezoelectric block to the direction of movement of the moving block, thereby stretching or compressing the piezoelectric block.

[0022] According to the cantilever vibration energy harvesting device, the first amplification component includes a pair of first connecting rods, which are located on both sides of the moving block along the moving direction of the moving block.

[0023] According to the cantilever vibration energy harvesting device, the second amplification component further includes a mass block, which is connected to the cantilever beam at a third connection point.

[0024] In addition, this disclosure also provides a sensing device, including a sensor and the aforementioned cantilever vibration energy harvesting device, wherein the piezoelectric block of the cantilever vibration energy harvesting device is electrically connected to the sensor for supplying power to the sensor.

[0025] Compared to existing technologies, the aforementioned cantilever vibration energy harvesting device and sensing device, when an external force acts on the cantilever beam, increase the force applied to the moving block through the lever arm of the cantilever beam. Then, the moving block further increases the tensile or compressive force applied to the piezoelectric block through the first connecting rod. Through the amplification of the two forces, the output power of the cantilever vibration energy harvesting device is effectively improved. Attached Figure Description

[0026] To more clearly illustrate the specific implementation methods, the accompanying drawings used in the description of the implementation methods will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0027] Figure 1 This is a schematic diagram of a cantilever vibration energy harvesting device.

[0028] Figure 2 This is a schematic diagram of the piezoelectric component.

[0029] Figure 3 This is a structural schematic diagram of the first amplification component and the support component.

[0030] Figure 4 yes Figure 3 A magnified view of a section at V4.

[0031] Figure 5 This is a schematic diagram of the second amplification component.

[0032] Figure 6 This is a schematic diagram of the structure of a cantilever vibration energy harvesting device in another embodiment.

[0033] Explanation of main component symbols

[0034] Component Name Figure Labels Component Name Figure Labels base 10 cantilever beam 40 piezoelectric blocks 20 First connection point 401 Connecting block 21 Second connection point 402 Pull rod 22 Third connection point 403 Move block 30 mass block 41 First connecting rod 31 support block 50 Second connecting rod 51

[0035] The following detailed embodiments will further illustrate this disclosure in conjunction with the above-described drawings. Detailed Implementation

[0036] To better understand the above-mentioned objectives, features, and advantages of this disclosure, the disclosure will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. Many specific details are set forth in the following description to provide a thorough understanding of this disclosure; the described embodiments are merely a part of the embodiments of this disclosure, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this disclosure without inventive effort are within the scope of protection of this disclosure.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of this disclosure.

[0038] In various embodiments, for ease of description and not limitation of this disclosure, the term "connection" used in the patent application specification and claims is not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. Terms such as "upper," "lower," "below," "left," and "right" are used only to indicate relative positional relationships; when the absolute position of the described object changes, the relative positional relationship also changes accordingly.

[0039] This disclosure first provides a sensing device including a sensor and a cantilever vibration energy harvesting device electrically connected to the sensor, which generates electrical energy by capturing vibration interference from the environment, thereby powering the sensor.

[0040] Figure 1 This is a schematic diagram of a cantilever vibration energy harvesting device. Figure 1 As shown, the cantilever vibration energy harvesting device includes a base 10, a piezoelectric component, a support component, a first amplification component, and a second amplification component. The base 10 is used to install and support other components of the cantilever vibration energy harvesting device. The support component is used to support and install the piezoelectric component. The first and second amplification components are used to amplify the external vibration energy, applying the force F1 to the piezoelectric component after two stages of amplification. The piezoelectric component converts the force F3 into a voltage output, thereby powering the sensor.

[0041] The base 10 has a generally "C"-shaped structure, with the top for mounting the first amplification component, the middle recessed portion for mounting the piezoelectric component, and the bottom for supporting the piezoelectric component via a support component. Those skilled in the art will understand that the base 10 can also have other structures, and this application does not limit this.

[0042] Figure 2 This is a schematic diagram of the piezoelectric component. (Example:) Figure 1 and 2 As shown, the piezoelectric assembly includes a piezoelectric block 20, a pull rod 22, and a pair of connecting blocks 21. The pull rod 22 is used to pull the piezoelectric block 20 through the pair of connecting blocks 21, thereby applying a certain prestress to the piezoelectric block 20 to prevent the piezoelectric block 20 from being stretched and damaged.

[0043] Specifically, the piezoelectric block 20 is made of piezoelectric material, a crystalline material that exhibits a voltage between its two ends when subjected to pressure. The piezoelectric block 20 is electrically connected to the sensor, and a voltage is generated by applying pressure or tension to the piezoelectric block 20, thus powering the sensor. Connecting blocks 21 are connected to both ends of the piezoelectric block 20 in the tensile direction, and the two ends of the pull rod 22 are connected to the connecting blocks 21, used to apply a pre-stress to the piezoelectric block 20 by pulling it through the connecting blocks 21. In this embodiment, the piezoelectric block 20 includes a through hole extending along the tensile direction, and the pull rod 22 passes through the through hole to connect a pair of connecting blocks 21.

[0044] In use, the pull rod 22 pulls the connecting blocks 21 at both ends of the piezoelectric block 20. The nuts at both ends of the pull rod 22 are adjusted according to actual needs, thereby applying a preset pressure to the piezoelectric block 20. During operation, this pre-pressure is always greater than the tensile or compressive force F3 applied to the piezoelectric block 20 by the first and second amplification components. Thus, the piezoelectric block 20 can always operate in a compressed state. Due to the strong compressive strength and weak tensile strength of piezoelectric materials, applying pre-pressure to the piezoelectric block 20 through the pull rod 22 and connecting blocks 21 ensures that the piezoelectric block 20 always operates in a compressed state, effectively preventing it from being damaged by tension.

[0045] A support assembly connects the base 10 and the piezoelectric assembly, linking the piezoelectric block 20 and the base 10, and supports the piezoelectric block 20. As an example, in this embodiment, the support assembly includes a support block 50 and a second connecting rod 51. The piezoelectric block 20 is movably connected to the base 10 via the support block 50 and the second connecting rod 51, thereby supporting the piezoelectric block 20. The support block 50 is generally block-shaped, with its bottom fixedly connected to the base 10. The second connecting rod 51 rotatably connects the support block 50 and the piezoelectric block 20, supporting the piezoelectric block 20. In this embodiment, there is a pair of second connecting rods 51, located on both sides of the support block 50. The two ends of each second connecting rod 51 are rotatably connected to the connecting block 21 of the piezoelectric assembly via a soft or elastic material, so that the support block 50 can support the connecting block 21 and the piezoelectric block 20 via the second connecting rods 51 on both sides. When in use, the piezoelectric block 20 moves vertically under the traction of the first amplification component and the second amplification component, and the movement of the piezoelectric block 20 is supported by the swing of the first connecting rod 31.

[0046] Figure 3 This is a schematic diagram of the piezoelectric block 20 and the first amplification component. (See attached diagram.) Figure 1 and Figure 3 As shown, the first amplification component includes a moving block 30 and a first connecting rod 31. Under the action of force F2, the moving block 30 amplifies the force F2 and then stretches or compresses the piezoelectric block 20 through the first connecting rod 31.

[0047] Specifically, the movable block 30 is vertically movable, and the first connecting rod 31 rotatably connects the movable block 30 and the connecting block 21 at the end of the piezoelectric block 20. In this embodiment, there is a pair of first connecting rods 31, located on both sides of the movable block 30 along its moving direction. One end of the first connecting rod 31 is connected to the movable block 30 via a soft or elastic material, and the other end is connected to the connecting block 21 at the end of the piezoelectric block 20 in the same manner. In other embodiments, the two ends of the first connecting rod 31 may also be connected to the movable block 30 and the connecting block 21 via hinges, rotating parts, etc., and this application does not impose any limitations on this. During operation, the movable block 30 moves vertically, causing the first connecting rod 31 to swing, thereby stretching or compressing the piezoelectric block 20 through the connecting block 21.

[0048] Figure 4 yes Figure 3 A magnified view of a section at V4. (See image below.) Figure 3 and Figure 4As shown, the length of the first connecting rod 31 is greater than the vertical distance from the connection point of the first connecting rod 31 and the piezoelectric block 20 to the moving direction of the moving block 30. Thus, the first connecting rod 31 has an angle of inclination α with the horizontal plane in its normal state. When the moving block 30 moves under the action of the pulling force F2, it pulls the first connecting rod 31 to swing near the vertical direction from the connection point of the first connecting rod 31 and the piezoelectric block 20 to the moving direction of the moving block 30, thus stretching the piezoelectric block 20 and applying a pulling force F3 to the piezoelectric block 20. Alternatively, it moves along a vertical direction away from the connection point of the first connecting rod 31 and the piezoelectric block 20 to the moving direction of the moving block 30, thus compressing the piezoelectric block 20 through the first connecting rod 31 and applying a pressure F3 to the piezoelectric block 20. Those skilled in the art can set the travel distance of the moving block 30 as needed, thereby controlling the magnitude of the pulling or pressure on the piezoelectric block 20. According to mechanical calculation methods, in Figure 3 and Figure 4 In the structure shown, the support blocks 50 and the moving blocks 30 on both sides of the piezoelectric block 20 simultaneously apply the same force F3 to the piezoelectric block 20 through the second connecting rod 51 and the first connecting rod 31. Therefore, the conversion relationship between force F2 and force F3 is as follows:

[0049]

[0050] Since the value of angle α is small and the value of cota is greater than 1, the value of force F3 is greater than the value of force F2, and the first amplifying component can thus amplify the force F2.

[0051] Figure 5 This is a schematic diagram of the second amplification component. (See attached diagram.) Figure 1 and Figure 5 As shown, the second amplification component includes a cantilever beam 40 and a mass block 41. The mass block 41 vibrates under external force interference, applying a force F1 to the cantilever beam 40. The force F1 is amplified by the cantilever beam 40 and then applies a force F2 to the moving block 30. Specifically, the cantilever beam 40 extends generally horizontally, rotatably connecting to the base 10 at a first connection point 401, connecting to the moving block 30 at a second connection point 402, and connecting to the mass block 41 at a third connection point 403. In this embodiment, the first connection point 401 is located at one end of the cantilever beam 40, the third connection point 403 is located at the other end of the cantilever beam 40, and the second connection point 402 is located between the first connection point 401 and the second connection point 402 along the length of the cantilever beam 40. When the mass block 41 vibrates under external force interference, the mass block 41 drives the cantilever beam 40 to swing relative to the base 10, and the cantilever beam 40 drives the moving block 30 to move. The moving block 30 stretches or compresses the piezoelectric block 20 through the first connecting rod 31.

[0052] like Figure 5 As shown, the distance L1 between the first connection point 401 and the third connection point 403 is greater than the distance L2 between the first connection point 401 and the second connection point 402. According to the calculation method for the rotational torque of the cantilever beam 40, the force F1 applied to the third connection point 403 and the force F3 applied to the second connection point 402 are calculated using the following formula:

[0053]

[0054] Since the distance L1 is much greater than the distance L2, the force F1 can be amplified by the cantilever beam 40, and the force F2 applied to the moving block 30 is also much greater than the force F1, thus achieving the second-level force amplification.

[0055] Figure 6 This is a schematic diagram of another embodiment of the cantilever vibration energy harvesting device. (See diagram below.) Figure 6 As shown, Figure 6 The illustrated implementation method and Figure 1 The difference in the illustrated embodiment is that, in this embodiment, the support assembly includes a support block 50, and the connecting block 21 is movably connected to the support block 50 along the stretching or compression direction of the piezoelectric block 20. For example, the connecting block 21 can be movably connected to a pair of the connecting blocks 21 by a slider-rail assembly, or it can be movably connected to a pair of the connecting blocks 21 by a roller structure.

[0056] In this embodiment, since only the moving block 30 on one side of the piezoelectric block 20 stretches or compresses the piezoelectric block 20 via the first connecting rod 51, Figure 6 In the illustrated embodiment, the formula for calculating the relationship between force F3 and force F2 is as follows:

[0057]

[0058] Similarly, since the value of angle α is small and the value of cota is greater than 2, the value of force F3 is greater than the value of force F2, and the first amplifying component can also amplify the force F2.

[0059] The following combination Figure 1 Describe in detail the working process of the entire cantilever vibration energy harvesting device.

[0060] After the cantilever vibration energy harvesting device is installed in a suitable position, the mass block 41 vibrates under external force interference. The mass block 41 is subjected to force F1 and moves in the vertical direction. The force F1 is amplified by the second amplification component and the first amplification component in sequence.

[0061] 1) Amplification process of the second amplification component

[0062] Mass block 41 applies force F1 to the third connection point 403 of cantilever beam 40. During the swinging process of cantilever beam 40, it drives moving block 30 to move roughly in the vertical direction at the second connection point 402. Cantilever beam 40 applies vertical force F2 to moving block 30. In this way, the force F1 is amplified into force F2 by the second amplification component.

[0063]

[0064] 2) The amplification process of the first amplification component

[0065] Under the action of force F2, the movable block 30 moves roughly vertically, causing the first connecting rods 31 on both sides of the movable block 30 to swing synchronously. The first connecting rods 31 apply force F3 to the piezoelectric block 20 through the connecting block 21. In this way, the first amplification component amplifies the force F2 into force F3.

[0066]

[0067] As can be seen from the above formula, the second amplification component has an amplification parameter L1 / L2, while the first amplification component has an amplification parameter cota. After the force F1 is amplified by the two-stage amplification components (the second and first amplification components), it is applied to the piezoelectric block 20 as a force F3, thereby generating a voltage output on the electrodes of the piezoelectric block 20. Since the output power of a piezoelectric material is theoretically proportional to the square of the force it experiences, this series amplification structure using the second and first amplification components can significantly improve the output power of the cantilever vibration energy harvesting device. Figure 4 The calculation process of the illustrated implementation is similar, the only difference being that the amplification parameter of the first amplification component is 1 / 2*cota, and the rest is the same, so it will not be described again here.

[0068] When an external force acts on the cantilever beam 40, the aforementioned cantilever vibration energy harvesting device and sensing device increase the force applied to the moving block 30 through the lever arm of the cantilever beam 40. Then, the moving block 30 further increases the tensile or compressive force applied to the piezoelectric block 20 through the first connecting rod 31. Through the amplification of the two forces, the output power of the cantilever vibration energy harvesting device is effectively improved.

[0069] Furthermore, by applying a preload of a specified magnitude to the piezoelectric block 20 through the pull rod 22, the stress on the piezoelectric block 20 is always negative during the operation of the piezoelectric energy harvesting device, that is, the piezoelectric block 20 is always in a compressed state, thereby avoiding damage to the piezoelectric block 20 due to stretching and improving the reliability of the piezoelectric energy harvesting device.

[0070] In the several specific embodiments provided in this disclosure, it will be apparent to those skilled in the art that this disclosure is not limited to the details of the exemplary embodiments described above, and that this disclosure can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of this disclosure is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be embraced within this disclosure. Furthermore, it is clear that the word "comprising" does not exclude other units or steps, and the singular does not exclude the plural. Terms such as "first," "second," etc., are used to denote names and do not indicate any particular order.

[0071] The above embodiments are only used to illustrate the technical solutions of this disclosure and are not intended to limit it. Although this disclosure has been described in detail with reference to the above preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions to the technical solutions of this disclosure should not depart from the spirit and scope of the technical solutions of this disclosure.

Claims

1. A cantilever vibration energy harvesting device, characterized in that, include: Base; A piezoelectric assembly, including a piezoelectric block connected to the base; A first amplification component includes a movable block and a first connecting rod, the first connecting rod being rotatably connected to the movable block and the piezoelectric block; The second amplification component includes a cantilever beam, which is rotatably connected to the base at a first connection point and to the movable block at a second connection point; When the cantilever beam swings relative to the base, it drives the moving block to move, and the moving block stretches or compresses the piezoelectric block through the first connecting rod; The piezoelectric component also includes: A pair of connecting blocks are respectively connected to both ends of the piezoelectric block in the stretching direction. The first connecting rod is connected to the connecting blocks, and the piezoelectric block is stretched or compressed through the connecting blocks. A pull rod, connected to the connecting block, is used to apply a prestress that compresses the piezoelectric block to the piezoelectric block through the connecting block; The length of the first connecting rod is greater than the vertical distance between the connection point of the first connecting rod and the piezoelectric block and the horizontal plane where the connection point of the first connecting rod and the moving block is located. When the moving block moves, it pulls the first connecting rod to swing along a vertical direction from the connection point between the first connecting rod and the piezoelectric block to the direction of movement of the moving block, thereby stretching or compressing the piezoelectric block.

2. The cantilever vibration energy harvesting device as described in claim 1, characterized in that, The piezoelectric block includes a through hole extending in the stretching direction, and the pull rod passes through the through hole to connect a pair of the connecting blocks.

3. The cantilever vibration energy harvesting device as described in claim 1, characterized in that, It also includes a support assembly for supporting the piezoelectric block, the support assembly connecting the piezoelectric block and the base.

4. The cantilever vibration energy harvesting device as described in claim 3, characterized in that, The support components include: Support block, connected to the base; The second connecting rod rotatably connects the support block and the piezoelectric block, and is used to support the piezoelectric block.

5. The cantilever vibration energy harvesting device as described in claim 4, characterized in that, The connecting block is movably connected to the support block along the stretching or compression direction of the piezoelectric block.

6. The cantilever vibration energy harvesting device as described in claim 5, characterized in that, The first amplification component includes a pair of first connecting rods, which are located on both sides of the moving block along the moving direction of the moving block.

7. The cantilever vibration energy harvesting device as described in claim 1, characterized in that, The second amplification component also includes a mass block, which is connected to the cantilever beam at a third connection point.

8. A sensing device, characterized in that, The device includes a sensor and a cantilever vibration energy harvesting device as described in any one of claims 1-7, wherein the piezoelectric block of the cantilever vibration energy harvesting device is electrically connected to the sensor for supplying power to the sensor.

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