CN211531019U

CN211531019U - Piezoelectric cantilever beam circumference array structure based on magnetic attraction

Info

Publication number: CN211531019U
Application number: CN201922245765.2U
Authority: CN
Inventors: 朱铭昊
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-12-14
Filing date: 2019-12-14
Publication date: 2020-09-18
Anticipated expiration: 2029-12-14

Abstract

The utility model discloses a piezoelectricity cantilever beam circumference array structure based on magnetic attraction. The piezoelectric actuator mainly comprises a power rotor 1 attached with a cylindrical permanent magnet 2, a rotating shaft 3 and more than one piezoelectric strain component; the piezoelectric strain component is arranged on the upper part of the rotating shaft 3 in a cantilever beam mode; the power rotor is arranged at the lower part of the rotating shaft and can rotate around the rotating shaft, and the direction of the magnetic field of the permanent magnet 2 on the power rotor is parallel to the axis of the rotating shaft 3; piezoelectric strain sheets which are corresponding up and down are laid near the iron root of the cantilever beam of the piezoelectric strain component. Adopt the utility model discloses a structure, collect and utilize in nature and the multiple energy that spreads in people's production and life, and have the superimposed function of wide band. The MEMS wind power generator can be manufactured by adopting an MEMS process to supply power for loads such as human body wearable equipment and the like, and can also be used for collecting natural wind power.

Description

Piezoelectric cantilever beam circumference array structure based on magnetic attraction

Technical Field

The utility model relates to a fine motion energy collecting device technical field.

Background

The conventional battery needs to be charged or replaced due to the limitation of the capacity and the service life thereof, which causes great waste and inconvenience, and severely restricts the development of the wireless sensor network. And energy is obtained from the natural environment, namely the environment. The energy is required to be obtained from the environment because part of the nodes of the wireless sensing network often work in the environment which is remote and bad and difficult for operators to enter (especially some military applications) to provide a sustainable power supply system for the nodes of the wireless sensing network, the application potential of the wireless sensing network can be fully exerted, and the wireless sensing network has the advantages of uninterrupted work, easiness in installation, low maintenance cost, clean and renewable energy sources, feasible long-term scheme and the like.

Compared with other types of energy collectors, the piezoelectric type energy collector has more advantages, except the risk of possible failure, the device which works by utilizing the piezoelectric effect has simple and compact structure, high output energy density, no need of an external voltage source for starting, long service life, compatibility with the MEMS processing technology, high output voltage and stronger electromechanical coupling when adopting the piezoelectric single crystal. The method has excellent flexibility and expansibility in wide application background, especially in system intelligence, micro-scale and integration. Piezoelectric energy harvesting can be adopted for linear array type energy harvesting, but array type devices are generally used for harvesting periodic linear vibration energy sources, and the type and range of energy harvesting are greatly limited.

SUMMERY OF THE UTILITY MODEL

In view of the above insufficiency of the prior art, the purpose of the utility model is to: a novel piezoelectric cantilever beam circumferential array structure attracted by magnetic force is designed, so that the piezoelectric cantilever beam circumferential array structure can collect and utilize various kinds of scattered energy in nature and production and life of people, and has a broadband superposition function. The MEMS wind power generator can be manufactured by adopting an MEMS process to supply power for loads such as human body wearable equipment and the like, and can also be used for collecting natural wind power.

The purpose of the utility model is realized by adopting the following technical means.

A piezoelectric cantilever beam circumference array structure based on magnetic attraction. The piezoelectric actuator mainly comprises a power rotor 1 attached with a cylindrical permanent magnet 2, a rotating shaft 3 and more than one piezoelectric strain component; the piezoelectric strain component is arranged on the upper part of the rotating shaft 3 in a cantilever beam mode; the power rotor is arranged at the lower part of the rotating shaft and can rotate around the rotating shaft 3, and the direction of the magnetic field of the permanent magnet 2 on the power rotor is parallel to the axis of the rotating shaft 3; piezoelectric strain sheets 4 which are up and down corresponding are laid near the iron root of the cantilever beam of the piezoelectric strain component.

One end of the cantilever beam is fixed, and the other end is a free end. The root of the fixed end is piezoelectric ceramic, namely a component for converting mechanical energy into electric energy. When the external acting force acts on the free end of the cantilever beam, the cantilever beam deforms, the piezoelectric element at the root of the fixed end generates electric energy, and the conductor leads the charge current on the piezoelectric strain component into the power driving or electric energy storage device.

Adopt the utility model discloses a structure, collect and utilize in nature and the multiple energy that spreads in people's production and life, and have the superimposed function of wide band. The MEMS wind power generator can be manufactured by adopting an MEMS process to supply power for loads such as human body wearable equipment and the like, and can also be used for collecting natural wind power.

Drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present invention.

Fig. 2 is a MATLAB/SIMULINK simulation diagram according to an embodiment of the present invention.

Detailed Description

The structure of the present invention will be described in detail with reference to the accompanying drawings.

Fig. 1 shows an embodiment of the present invention based on a circumferential array structure of a magnetically attracted piezoelectric cantilever. In this example, three piezoelectric strain members, piezoelectric strain member a, piezoelectric strain member B, and piezoelectric strain member C are used. The piezoelectric actuator mainly comprises a power rotor 1 attached with a cylindrical permanent magnet 2, a rotating shaft 3 and more than one piezoelectric strain component; the piezoelectric strain component is fixed on the upper part of the rotating shaft 3 through a disc 5 in a cantilever beam mode; the rotor 1 is arranged at the lower part of the rotating shaft and can rotate around the rotating shaft 3, and the direction of the magnetic field of the permanent magnet 2 on the rotor is parallel to the axis of the rotating shaft 3; laying corresponding piezoelectric strain gauges up and down near the iron root of the cantilever beam of the piezoelectric strain component; the flow of electrical charge on the piezoelectric strain member is directed by a conductor to a power drive or electrical energy storage device.

The dimensions of the piezoelectric strain gauges on the piezoelectric strain members may or may not be the same. In the embodiment, the three piezoelectric strain components are distributed in a plane with 120-degree included angles, and the widths of the piezoelectric ceramic piezoelectric strain pieces of the three piezoelectric strain components are 20 mm; when the lengths are different, the first-order resonance frequencies are not exactly the same but are close to each other with a certain difference. The array mode with the small difference can more effectively utilize the excitation of broadband, so that higher electric energy output can be generated in a larger frequency fluctuation range. For the small difference, simulation is performed by using matlab/simulink, and the simulation is shown in fig. 2. The resonant frequency of each piezoelectric cantilever beam is determined, and then the size parameter of each beam is calculated, so that the optimal corresponding relation of the piezoelectric strain gauge length can be obtained quantitatively. In the embodiment, the resonant frequencies of the three piezoelectric cantilever beams are 47.5Hz, 50Hz and 52.5Hz, the widths are 20mm, the thicknesses are 1mm, and the half-power bandwidth coincidence is achieved. This set of simulation parameters will be used as a basis for the fabrication of a cantilever beam, and the bandwidth over which the device can operate is optimized when there is such a relationship between the lengths of the piezoelectric strain gauges. The best relationship is obtained by calculating according to the half-wave band superposition, wherein A is 80mm, B is 83mm, and C is 85 mm.

In practical implementation, the power rotor can be in the shape of a fan, a disc, a semicircular disc, a circular ring and a spoke structure. In order to enable the power rotor to have better stability, the power rotor adopts a structure which enables the gravity center of the power rotor to be distributed towards the edge and increases the rotational inertia, such as a hub structure. Adopt the scheme of the utility model, compare in linear array energy collecting device, be applicable to human wearable equipment more (for example in the wrist-band's of integration wrist-watch), because human arm is at the swing in-process, the rotation that the rotor can not stop under the effect of power promptly. The power rotor can be coupled with other power collecting mechanisms, such as a windmill impeller, to collect airflow power besides collecting tiny momentum by the power rotor.

Claims

1. A piezoelectric cantilever beam circumference array structure based on magnetic attraction is characterized by mainly comprising a power rotor (1) attached with a cylindrical permanent magnet (2), a rotating shaft (3) and more than one piezoelectric strain component; the piezoelectric strain component is arranged on the upper part of the rotating shaft (3) in a cantilever beam mode; the power rotor is arranged at the lower part of the rotating shaft and can rotate around the rotating shaft, and the magnetic field direction of the permanent magnet (2) on the power rotor is parallel to the axis of the rotating shaft (3); piezoelectric strain sheets which are corresponding up and down are laid near the iron root of the cantilever beam of the piezoelectric strain component.

2. The magnetically attractive piezoelectric cantilever circumferentially arrayed configuration of claim 1, wherein there are three piezoelectric strain members disposed in planes with 120 degrees included angle, the resonant frequencies of the three piezoelectric strain members are 47.5Hz, 50Hz, 52.5Hz, respectively, and the length ratio of the piezoelectric strain gauges is 80:83: 85.

3. The magnetically attractable based piezoelectric cantilever circumferential array configuration of claim 1, wherein the power rotor is in the form of a disk, a half-disk, a ring, or a spoke.

4. The magnetically attractive piezoelectric cantilever circumferentially arrayed configuration of claim 1, wherein the power rotor is configured such that the center of gravity of the power rotor is distributed towards the rim to increase the moment of inertia.

5. The magnetically attractive based piezoelectric cantilever circumferential array configuration of claim 1, wherein the power rotor is coupled with an air flow power harvesting device.