A rotary-straight conversion piezoelectric micro-wind energy collector

Abstract

The application discloses a rotary-straight conversion piezoelectric type wind energy collector, which comprises a non-powered wind cap, a central shaft, a cylindrical cam, a push rod with a ball head, a spring, a spring base, a spring end, a piezoelectric sheet and a supporting and fixing assembly. The wind cap drives the central shaft and the cylindrical cam to rotate synchronously, the cam surface groove drives the push rod to vertically reciprocate along the guide hole through the ball head, the push rod drives the spring to stretch and contract through the spring end, the spring applies axial pressure along the polarization direction of the piezoelectric sheet to the piezoelectric sheet through the spring base, so that the piezoelectric sheet is pressed in the d 33 Mode to convert mechanical energy into electrical energy. The application converts rotary motion into reciprocating pressure in the axial direction of the piezoelectric sheet, the stress is uniform and there is no stress concentration, the starting wind speed is low, the fatigue resistance is strong, and the application is suitable for continuously supplying power for low-power Internet of Things nodes in urban micro-wind environment.

Description

Technical Field

[0001] This invention relates to the field of energy harvesting technology, and in particular to a rotary-to-direction piezoelectric micro-wind energy harvester. Background Technology

[0002] As a widely available, clean, and renewable energy source, wind energy harvesting technology has become a key direction for solving the battery life problem of low-power devices. Among them, piezoelectric wind energy harvesting devices have attracted widespread attention due to their advantages such as compact structure, rapid response, and absence of electromagnetic interference. Most existing wind piezoelectric energy harvesting devices adopt a cantilever beam structure, where wind energy drives the cantilever beam to undergo alternating bending deformation, causing the piezoelectric material attached to it to deform at a certain angle. 31 The mode converts mechanical strain into electrical energy.

[0003] In traditional cantilever beam structures, the piezoelectric material is subjected to continuous alternating bending stress during operation, resulting in highly uneven internal stress distribution. The maximum stress is concentrated near the fixed end of the beam. This localized stress concentration effect, under long-term alternating loads, easily induces the initiation and propagation of microcracks in the piezoelectric ceramic material, ultimately leading to device fatigue failure, reduced power generation performance, and even overall fracture, severely limiting the device's lifespan and operational reliability. On the other hand, cantilever beam piezoelectric energy harvesters typically rely on resonance conditions at specific frequencies to achieve high energy conversion efficiency. However, wind speeds in urban micro-wind environments are random and variable, with low frequencies, making it difficult to meet the resonance excitation requirements of cantilever beam structures. This results in actual output power being far lower than the theoretical design value, leading to low energy conversion efficiency. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a rotary-to-vertical conversion piezoelectric micro-wind energy harvester, comprising a wind energy input component, a rotary-to-vertical conversion transmission component, a pressure transmission component, a piezoelectric power generation unit, and a support and fixing component; the wind energy input component, the rotary-to-vertical conversion transmission component, the pressure transmission component, and the piezoelectric power generation unit are all mounted on the support and fixing component; The wind energy input component includes a non-powered turbine-type wind cap and a central shaft. The rotary-to-linear conversion transmission component includes a cylindrical cam and a push rod. The non-powered turbine-type wind cap is fixedly connected to the central shaft and is used to drive the central shaft to rotate. The central shaft is fixedly connected to the cylindrical cam and is used to drive the cylindrical cam to rotate synchronously. The cylindrical cam is connected to the push rod. When the cylindrical cam rotates, it drives the push rod to reciprocate in the vertical direction. The top end of the push rod is fixedly connected to the pressure transmission component. The pressure transmission component abuts against the piezoelectric power generation unit. The reciprocating motion of the push rod acts on the piezoelectric power generation unit through the pressure transmission component, causing the piezoelectric power generation unit to generate electrical energy.

[0005] Furthermore, the central shaft portion is tapped and rigidly connected to the cylindrical cam via a nut.

[0006] Furthermore, the cylindrical cam surface has raised and recessed grooves, and the push rod end is provided with a ball head that matches the groove of the cylindrical cam. When the cylindrical cam rotates, the ball at the push rod end moves along the cam groove, converting the rotational motion into a vertical reciprocating motion.

[0007] Furthermore, the pressure transmission assembly includes a spring, a spring base, and a spring end; the piezoelectric power generation unit includes a piezoelectric sheet and a copper sheet; and the support and fixing assembly includes a three-sided fixing device, a connecting plate, a bearing, a wind cap support device, and a nut.

[0008] Furthermore, the spring base and the spring end are respectively fixed at both ends of the spring; the spring end is fixedly connected to the push rod, the spring base is located at the lower end of the spring, and its bottom surface contacts the upper surface of the piezoelectric sheet. The spring applies preload to the piezoelectric sheet through the spring base.

[0009] Furthermore, when the push rod moves up and down, it drives the spring to perform a reciprocating motion of compression and recovery through the spring end. The spring applies a periodically changing axial pressure to the piezoelectric sheet through the spring base. The piezoelectric sheet converts mechanical energy into electrical energy based on the piezoelectric effect.

[0010] Furthermore, the axial pressure applied by the spring is consistent with the polarization direction of the piezoelectric element, and the piezoelectric element adopts a d-axis polarization direction. 33 model.

[0011] Furthermore, a copper sheet is provided in the middle of the piezoelectric sheet.

[0012] Furthermore, the three-sided fixing device is fixedly connected to the wind cap support device through a connecting plate. A slot is opened on one side of the three-sided fixing device in the axial direction. The three-sided fixing device and the connecting plate are connected through the slot, and the connecting plate is fixed to the wind cap support device. The three-sided fixing device is provided with a guide hole to fix the push rod and constrain its vertical movement direction.

[0013] Furthermore, the outer ring of the bearing is fixed to the end and end of the three-sided fixing device, and the inner ring is fixed to the central shaft to realize the rotation of the central shaft.

[0014] The above technical solution has the following advantages or beneficial effects: This invention utilizes the rotation of a non-powered wind cap to drive the central shaft, which in turn drives the cylindrical cam to rotate. The ball at the end of the push rod follows the cam groove, converting the rotational motion into a vertical reciprocating motion. The push rod passes through the guide hole of the three-sided fixing device, and its top end connects to the spring end, pushing the spring connected to the spring end to reciprocate. This reciprocating motion of the spring is then converted into a force that changes axially on the piezoelectric element. (Distinct from d) 31 Alternating bending stress in bending mode, d33 The mode generates electricity by applying axial compressive stress along the polarization direction of the piezoelectric material. The stress is uniform and there is no local stress concentration, which fundamentally solves the fatigue failure problem of cantilever beam structures. At the same time, the non-powered turbine wind cap can be used for urban micro-wind collection, and the structure is compact to adapt to the axial installation layout in confined spaces. Attached Figure Description

[0015] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.

[0016] Figure 1 This is a schematic diagram of the structure of a rotary-to-direction piezoelectric micro-wind energy harvester according to the present invention; Figure 2 This is a schematic diagram of the internal structure of the rotary-to-linear conversion. Figure 3 This is a schematic diagram of the power generation unit.

[0017] Among them, 1-three-sided fixing device, 2-connecting plate, 3-push rod (with ball head), 4-cylindrical cam, 5-central shaft, 6-non-powered wind cap, 7-bearing, 8-wind cap support device, 9-piezoelectric sheet, 10-copper sheet, 11-spring, 12-spring end, 13-spring base. Detailed Implementation

[0018] It should be noted that the following detailed descriptions are exemplary and intended to provide further illustration of the invention. Unless otherwise specified, 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 invention pertains.

[0019] Example 1 like Figures 1-3 As shown, this embodiment of the invention provides a rotary-to-direct-current piezoelectric micro-wind energy harvester for converting wind energy into electrical energy in urban micro-wind environments. The rotary-to-direct-current piezoelectric micro-wind energy harvester includes a wind energy input component, a rotary-to-direct-current conversion transmission component, a pressure transmission component, a piezoelectric power generation unit, and a support and fixing component.

[0020] The wind energy input component, the rotary-to-linear conversion transmission component, the pressure transmission component, and the piezoelectric power generation unit are all mounted on a supporting and fixing component. The wind energy input component includes a non-powered turbine-type wind cap 6 and a central shaft 5. The rotary-to-linear conversion transmission component includes a cylindrical cam 4 and a push rod 3. The non-powered turbine-type wind cap 6 is fixedly connected to the central shaft 5 and is used to drive the central shaft 5 to rotate. The central shaft 5 is fixedly connected to the cylindrical cam 4 and is used to drive the cylindrical cam 4 to rotate synchronously. The cylindrical cam 4 is connected to the push rod 3. When the cylindrical cam 4 rotates, it drives the push rod 3 to reciprocate in the vertical direction. The top end of the push rod 3 is fixedly connected to the pressure transmission component. The pressure transmission component abuts against the piezoelectric power generation unit. The reciprocating motion of the push rod 3 acts on the piezoelectric power generation unit through the pressure transmission component, causing the piezoelectric power generation unit to generate electrical energy.

[0021] Furthermore, the pressure transmission assembly includes a spring 11, a spring base 13, and a spring end 12; the piezoelectric power generation unit includes a piezoelectric sheet 9 and a copper sheet 10; the support and fixing assembly includes a three-sided fixing device 1, a connecting plate 2, a bearing 7, a wind cap support device 8, and a nut.

[0022] Furthermore, the central shaft 5 is partially tapped and rigidly connected to the cylindrical cam 4 via a nut.

[0023] Furthermore, the cylindrical cam 4 has raised and recessed grooves on its surface, and the push rod 3 has a ball head at its end. The ball head matches the groove of the cylindrical cam 4. When the cylindrical cam 4 rotates, the ball at the end of the push rod 3 moves along the cam groove, converting the rotational motion into a vertical reciprocating motion.

[0024] The groove is a spatial curve groove designed and machined on the working surface of a cylindrical cam according to a predetermined motion law, and the two side walls of the groove form the contour surface that drives the follower to move.

[0025] Furthermore, the spring 11 is disposed between the spring base 13 and the spring end 12, with the spring base 13 and the spring end 12 respectively fixed at both ends of the spring 11; the spring end 12 is fixedly connected to the push rod 3, and the spring base 13 is disposed at the lower end of the spring 11, with its bottom surface in contact with the upper surface of the piezoelectric sheet 9. The spring 11 applies a preload to the piezoelectric sheet through the spring base 13, and this preload persists when the device is stationary; when the push rod 3 moves up and down, it drives the spring to perform a reciprocating motion of compression and recovery through the spring end 12. The spring 11 applies a periodically changing axial pressure to the piezoelectric sheet through the spring base 13, and the piezoelectric sheet 9 converts mechanical energy into electrical energy based on the piezoelectric effect.

[0026] The axial pressure applied by spring 11 is consistent with the polarization direction of piezoelectric element 9, that is, piezoelectric element 9 adopts d... 33Pattern; different from cantilever beam d 31 Alternating bending stress in bending mode, d 33 The mode generates electricity by applying axial compressive stress along the polarization direction of the piezoelectric material, resulting in uniform stress distribution and no local stress concentration.

[0027] Furthermore, each spring end 12 is provided with a number of slots; the push rod 3 is fixed in the slots, and the number of slots is the same as the number of push rods (with ball heads).

[0028] Furthermore, a copper sheet 10 is provided in the middle of the piezoelectric sheet 9 to prevent the piezoelectric sheet from being damaged due to excessive pressure.

[0029] Furthermore, the three-sided fixing device 1 is fixedly connected to the wind cap support device 8 via the connecting plate 2. A slot is opened on one side of the three-sided fixing device 1 in the axial direction. The three-sided fixing device 1 and the connecting plate 2 are connected through the slot. The number of slots is consistent with the number of sides of the three-sided fixing device 1. The connecting plate 2 is fixed to the wind cap support device 8. The three-sided fixing device 1 is provided with a guide hole to fix the push rod 3 (with ball head) and constrain its vertical movement direction. There are two bearings 7. The outer ring is fixed to the end and end of the three-sided fixing device 1, and the inner ring is fixed to the central shaft 5 to realize the rotation of the central shaft 5.

[0030] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A piezoelectric micro-wind energy harvester with rotary-to-direct conversion, characterized in that, It includes a wind power input component, a rotary-to-vertical conversion transmission component, a pressure transmission component, a piezoelectric power generation unit, and a support and fixing component; the wind power input component, the rotary-to-vertical conversion transmission component, the pressure transmission component, and the piezoelectric power generation unit are all mounted on the support and fixing component; The wind energy input component includes a non-powered turbine-type wind cap and a central shaft. The rotary-to-linear conversion transmission component includes a cylindrical cam and a push rod. The non-powered turbine-type wind cap is fixedly connected to the central shaft and is used to drive the central shaft to rotate. The central shaft is fixedly connected to the cylindrical cam and is used to drive the cylindrical cam to rotate synchronously. The cylindrical cam is connected to the push rod. When the cylindrical cam rotates, it drives the push rod to reciprocate in the vertical direction. The top end of the push rod is fixedly connected to the pressure transmission component. The pressure transmission component abuts against the piezoelectric power generation unit. The reciprocating motion of the push rod acts on the piezoelectric power generation unit through the pressure transmission component, causing the piezoelectric power generation unit to generate electrical energy.

2. The piezoelectric micro-wind energy harvester with rotary-to-direct conversion according to claim 1, characterized in that, The central shaft is tapped and rigidly connected to the cylindrical cam via a nut.

3. A piezoelectric micro-wind energy harvester with rotary-to-direct conversion according to claim 1, characterized in that, The cylindrical cam surface has raised and recessed grooves, and the push rod end is provided with a ball head that matches the groove of the cylindrical cam. When the cylindrical cam rotates, the ball at the push rod end moves along the cam groove, converting the rotational motion into a vertical reciprocating motion.

4. A piezoelectric micro-wind energy harvester with rotary-to-direct conversion according to claim 1, characterized in that, The pressure transmission assembly includes a spring, a spring base, and a spring end; the piezoelectric power generation unit includes a piezoelectric sheet and a copper sheet; the support and fixing assembly includes a three-sided fixing device, a connecting plate, a bearing, a wind cap support device, and a nut.

5. A rotary-to-direction piezoelectric micro-wind energy harvester according to claim 4, characterized in that, The spring base and spring end are respectively fixed at both ends of the spring; the spring end is fixedly connected to the push rod, the spring base is set at the lower end of the spring, and its bottom surface is in contact with the upper surface of the piezoelectric sheet. The spring applies preload to the piezoelectric sheet through the spring base.

6. A rotary-to-direction piezoelectric micro-wind energy harvester according to claim 5, characterized in that, When the push rod moves up and down, it drives the spring to perform a reciprocating motion of compression and recovery through the spring end. The spring applies a periodically changing axial pressure to the piezoelectric sheet through the spring base. The piezoelectric sheet converts mechanical energy into electrical energy based on the piezoelectric effect.

7. A rotary-to-direction piezoelectric micro-wind energy harvester according to claim 6, characterized in that, The axial pressure applied by the spring is consistent with the polarization direction of the piezoelectric element, and the piezoelectric element adopts d... 33 model.

8. A piezoelectric micro-wind energy harvester with rotary-to-direct conversion according to claim 4, characterized in that, The piezoelectric element has a copper sheet in the middle.

9. A rotary-to-direction piezoelectric micro-wind energy harvester according to claim 4, characterized in that, The three-sided fixing device is fixedly connected to the wind cap support device through the connecting plate. A slot is opened on one side of the three-sided fixing device in the axial direction. The three-sided fixing device and the connecting plate are connected through the slot. The connecting plate is fixed on the wind cap support device. The three-sided fixing device is provided with a guide hole to fix the push rod and constrain its vertical movement direction.

10. A rotary-to-direction piezoelectric micro-wind energy harvester according to claim 4, characterized in that, The outer ring of the bearing is fixed to the beginning and end of the three-sided fixing device, and the inner ring is fixed to the central shaft to realize the rotation of the central shaft.

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