CN203406804U - Piezoelectric power generation device based on cantilever beam longitudinal vibration - Google Patents

Abstract

The utility model relates to a cantilever-beam based longitudinal vibration piezoelectric generation apparatus, belonging to the technical field of new energy and power generation. Two circular discs with circular protrusions are symmetrically arranged via screws, a piezoelectric oscillator is crimped in the middle and is made from piezoelectric ceramics and a metal sheet, the free end is provided with a weight block, and a spring is connected between the weight block and the lower circuit disc to balance the gravity of the weight block, after the circular discs are symmetrically arranged, the protrusions are just clamped on the metal sheet, close to the weight block, of the cantilever-beam type piezoelectric oscillator to take a fulcrum effect on the piezoelectric oscillator, when the weight block vibrates up and down, the piezoelectric oscillator bends and deforms under the support of the protrusions to convert mechanical energy into electric energy, thereby realizing energy recovery. The apparatus provided is advantageous in that the piezoelectric oscillator is free of being damaged due to excessive bending and deformation under large-amplitude vibration, the structure is simple, the reliability is high, and the quality of the weight block and the fixed frequency of the generation apparatus are changed, and the vibration energy recovery can be realized under low frequency and high frequency.

Description

Piezoelectric power generation device based on cantilever beam longitudinal vibration

technical field

The utility model belongs to the technical field of new energy and power generation, and in particular relates to a cantilever-beam-based longitudinal vibration piezoelectric power generation device, which is used for low-frequency, high-reliability longitudinal vibration energy recovery. the

Background technique

In order to meet the self-power supply requirements of micro-power electronic products and micro-miniature remote sensing and embedded detection systems, and to avoid the pollution of the environment by a large number of waste batteries, research on micro-miniature power generation devices based on the principles of electromagnetic, electrostatic, thermoelectric, capacitive and piezoelectric has been carried out. Become a frontier hotspot at home and abroad. All kinds of power generation devices have their own advantages and applicable fields. The advantages of piezoelectric vibration power generation devices are simple structure, easy manufacture, and realization of structural miniaturization and integration. In the fields of sensors, health monitoring and wireless transmission systems. the

There are many patent applications at home and abroad on the use of piezoelectric materials to recover environmental energy, most of which are for the purpose of vibration energy recovery. As we all know, for vibrating piezoelectric generators, only when the natural frequency of the piezoelectric vibrator is equal to the vibration frequency of the environment can a higher power generation capacity and energy conversion efficiency be achieved. However, the resonant frequency of the piezoelectric vibrator is usually high, among which the resonant frequency of the piezoelectric cantilever beam is several hundred Hz, and the resonant frequency of the circular piezoelectric vibrator is as high as several thousand Hz, while the environmental vibration frequency is generally tens of Hz, or even only Therefore, the effect of directly using the piezoelectric vibrator to collect environmental vibration energy is not obvious. In order to reduce the natural frequency of the piezoelectric vibrator, the current method is to install a lumped mass block at the end of the cantilever beam piezoelectric vibrator or at the center of the circular piezoelectric vibrator. In the working state, the piezoelectric vibrator has already produced a large deformation, and it is very easy to be damaged due to excessive deformation during operation. The reason is that the texture of the piezoelectric ceramic material is very brittle and its ability to withstand deformation is extremely limited. Even for a longer cantilever beam piezoelectric vibrator, the safe deformation is only at the millimeter level. In real life, conventional environmental vibration is mainly induced by the operation of various vehicles and human body movement. This type has the dual characteristics of low frequency and large amplitude. The longitudinal vibration amplitude of vehicles such as cars and bicycles can sometimes be up to several centimeters, or even tens of centimeters. It can be seen that the current portable vibration power generation device is difficult to obtain wider application in practice. the

Contents of the invention

Aiming at the limitation that the existing piezoelectric vibration power generation device can only be used for vibration energy recovery in an environment with small amplitude and high frequency, the utility model provides a high-frequency, stable and reliable circular cavity built-in cantilever beam piezoelectric The power generation device is used for energy recovery of low-frequency and large-amplitude vibrations in conventional environments such as bumps in various vehicles and human movement. the

The embodiment adopted by the utility model is: two discs with circular protrusions are installed symmetrically by screws, and a piezoelectric vibrator is crimped in the middle, and the piezoelectric vibrator is composed of piezoelectric ceramics and metal sheets, and the free end is installed There is a heavy block, and a spring is connected between the heavy block and the lower disc to balance the gravity of the heavy block; after the symmetrical installation of the disc, the protrusion just clamps the cantilever beam piezoelectric vibrator close to the heavy block On the metal sheet, it acts as a fulcrum for the piezoelectric vibrator. When the heavy object vibrates up and down, the piezoelectric vibrator is bent and deformed under the support of the protrusion, and the mechanical energy is converted into electrical energy, thereby realizing energy recovery. the

In the natural state, the heavy object at the free end of the piezoelectric vibrator is in a balanced state under the action of gravity and spring force, and the piezoelectric vibrator is also in a static state at this time. When the utility model is excited by the longitudinal vibration, the heavy object in the cavity will vibrate up and down, and the piezoelectric vibrator is also bent and deformed by the support of the protrusion. At the same time, the arc-shaped grooves on the disc can limit the excessive bending of the piezoelectric vibrator and prevent the piezoelectric vibrator from being damaged due to excessive deformation. the

The advantages and characteristics of the utility model are: ①The piezoelectric vibrator will not be damaged due to excessive bending deformation under large amplitude vibration, and has a simple structure and high reliability; ②The quality of the heavy block can be changed to change the natural frequency of the power generation device , to realize vibration energy recovery at low frequency and high frequency. the

Description of drawings

Fig. 1 is a structural cross-sectional view of a power generating device in a static state in a preferred embodiment of the present invention;

Fig. 2 is the plan view that removes upper disk of Fig. 1;

Fig. 3 is a partial enlarged view of the arc tip and the arc cavity in a preferred example of the utility model;

Fig. 4 is a cross-sectional view of a preferred embodiment of the utility model in a state of longitudinal vibration. the

Detailed ways

The embodiment adopted by the utility model is: two discs 3 with arc-shaped depressions are installed symmetrically by screws, and a piezoelectric vibrator is crimped in the middle, and the piezoelectric vibrator is composed of a piezoelectric ceramic 1 and a metal sheet 2. , the free end is equipped with a heavy block, and a spring 8 is connected between the heavy block 4 and the lower disc to balance the gravity of the heavy block; after the symmetrical installation of the disc, the protrusion 7 just clamps the cantilever beam The piezoelectric vibrator is close to the metal sheet of the heavy object, which acts as a fulcrum for the piezoelectric vibrator. When the heavy object 4 vibrates up and down, the piezoelectric vibrator is bent and deformed under the support of the protrusion 7, and the mechanical energy is converted into electrical energy. This enables energy recovery. the

In the natural state, the heavy object at the free end of the piezoelectric vibrator is in a balanced state under the action of gravity and spring force, and the piezoelectric vibrator is also in a static state at this time. When the utility model is excited by the longitudinal vibration, the weight block 4 in the cavity 6 will vibrate up and down, supported by the protrusion 7 so that the piezoelectric vibrator also bends and deforms. At the same time, the arc-shaped groove 5 on the disc 3 can also limit the over-bending of the piezoelectric vibrator to prevent the piezoelectric vibrator from being damaged due to excessive deformation. the

Claims (1)

1. A piezoelectric power generation device based on cantilever beam longitudinal vibration, characterized in that: two disks with circular protrusions are installed symmetrically by screws, and a piezoelectric vibrator is crimped in the middle, and the piezoelectric vibrator is formed by a piezoelectric vibrator. Composed of electric ceramics and metal sheets, a heavy block is installed at the free end, and a spring is connected between the heavy block and the lower disc to balance the gravity of the heavy block; after the symmetrical installation of the disc, the protrusion just clamps it The cantilever beam piezoelectric vibrator is close to the metal sheet of the heavy object, which acts as a fulcrum for the piezoelectric vibrator. When the heavy object vibrates up and down, the piezoelectric vibrator is bent and deformed under the support of the protrusion.

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