CN102801360B - Disk cam excited and limited high-power rotary piezoelectric wind generator - Google Patents

Abstract

The invention relates to a high-power rotary piezoelectric wind power generator with disc cam excitation and position limitation, belonging to the technical field of new energy and power generation. The frame is provided with a transduction cavity and an excitation cavity, the end of the transduction cavity is equipped with an end cover, the upper wall of the excitation cavity is equipped with a flange embedded with bearings, the side wall is embedded with a guide sleeve, and the lower wall is embedded with a bearing; the main shaft Installed on the frame through bearings, on which there is a disk cam for exciting the transducer and blades are installed; the transducer is composed of a base that is sleeved on the guide rod and riveted with each other, a piezoelectric vibrator, rivets and a force rod; The base and the guide rod are fixed on the end cover, the force applying rod is sleeved in the guide hole of the guide sleeve; the spring is sleeved on the force applying rod and pressed between the guide sleeve and the pressure block at the end of the guide rod, The block presses the balls against the disc cam surface. The advantage is that the disc cam placed on the vertical axis simultaneously excites multiple groups of piezoelectric vibrators in series and limits their deformation, has strong power generation capacity and wind direction adaptability, high reliability, and no contact impact and noise.

Description

High Power Rotary Piezoelectric Wind Generator with Disc Cam Excitation and Limitation

technical field

The invention belongs to the technical field of new energy and power generation, and in particular relates to a high-power rotary piezoelectric wind generator with disk cam excitation and position limitation, which provides real-time energy supply for micro-power wireless systems such as wireless sensor nodes.

Background technique

Wind energy widely exists in nature, and wind power generation has become one of the mainstream energy sources in the world today. In the past, people only paid attention to the research of large-scale wind power generation systems. In recent years, with the maturity of wireless sensor network technology and its application in environmental monitoring, health monitoring of large buildings and bridges, industry, military and public safety The popularity of micro-wind generators that provide continuous human energy supply has attracted widespread attention from scholars at home and abroad. The reason is that the energy of chemical batteries is limited, and their use time is far shorter than the life of wireless sensor monitoring systems. Therefore, it needs to be replaced frequently, which seriously restricts the popularization and application of the wireless sensor network monitoring system in remote and dangerous environments. The micro-wind generators that have been mentioned so far are basically based on the electromagnetic principle and the piezoelectric principle. Because the piezoelectric generator will not generate electromagnetic interference during the power generation process, it is more suitable for the application requirements of wireless systems such as wireless network nodes.

According to the source form and energy density of mechanical energy, bulk and sheet piezoelectric vibrators can be used to generate electricity, among which bulk piezoelectric vibrators require a large impact force, while sheet piezoelectric vibrators require a smaller excitation force, so they are more suitable Construct wind turbines with relatively low energy density. There are two main types of existing wind power generators constructed with sheet-type piezoelectric vibrators: one is the blowing excitation type, that is, the piezoelectric vibrator is directly blown by the wind to cause bending deformation and power generation, such as Chinese patents 97101500.7, 201110175062.2, 200910104106.5; the second is the rotary excitation type, that is, firstly use the wind to rotate the blades, and then the blades drive the rotating mechanism to move the piezoelectric vibrator to bend and deform and generate electricity, such as Chinese patents 200910081331.1, 201010519391.X, etc. The common feature of the above-mentioned piezoelectric generators is that the piezoelectric vibrator used is a cantilever beam structure, because the stress at the root is large during deformation, while the stress at the free end is zero, and the deformation is uncontrollable, and it is easy to cause the deformation of the root to be too large. damage, so the power generation capacity and reliability are low; at the same time, it is not suitable to use a simple force-applying mechanism to simultaneously stimulate multiple piezoelectric vibrators to generate power synchronously, so the overall power supply capacity is low, and it is difficult to realize the real-time performance of the power supply system; in addition, the current Some blowing generators can only be effectively excited when the wind direction is perpendicular to the surface of the piezoelectric vibrator, and cannot effectively collect energy from different wind directions.

Contents of the invention

The present invention provides a high-power rotary piezoelectric wind power generator with disk cam excitation and limit, so as to provide reliable and sufficient energy supply for the network nodes of the wireless sensor monitoring system under different wind environment conditions.

The technical solution adopted by the present invention is: the frame is provided with a transduction cavity and an excitation cavity, the end of the transduction cavity is installed with an end cover through screws, and the upper wall of the excitation cavity is equipped with a flange embedded with a bearing, The side wall is inlaid with a guide sleeve, and the lower wall is inlaid with a bearing; the main shaft is installed on the frame through the two bearings, and the part inside the excitation chamber is provided with a disc cam for exciting the transducer, and an external shaft end Blades are installed on the top; the transducer is composed of a base set on the guide rod and riveted in series with each other, a bowl-shaped piezoelectric vibrator, a solid rivet, a hollow rivet and a force rod; the piezoelectric vibrator is composed of a bowl-shaped metal substrate and an annular The base is fixed on the end cover by screws, and the end cap of the guide rod is pressed on the end cover; the force rod is set in the guide hole of the guide sleeve, and the pressure block at the end is placed In the excitation chamber; the spring is sleeved on the force rod and pressed between the guide sleeve and the pressure block at the end of the guide rod. The spring presses the ball embedded in the pressure block against the disc cam on the main shaft through the pressure block. surface.

According to the structure of the piezoelectric generator of the present invention, the ball inlaid on the pressure block at the end of the force applying rod is always pushed by the spring against the disc cam surface on the main shaft, so the deformation law and maximum deformation amount of the piezoelectric vibrator are determined by the disc cam surface. The surface shape of the cam and the eccentricity e are determined. In order to ensure that the piezoelectric wafer of the piezoelectric vibrator will not be damaged due to excessive deformation, the maximum eccentricity of the disc cam should be determined by the following formula: e _max =2δE _total (nE _single ), where δ is the piezoelectric vibrator 11 can withstand The maximum amount of one-way deformation, E _{is always} the output energy required by the generator, E _alone is the energy produced by a single piezoelectric vibrator for one reciprocating bending deformation, and n is the number of transducers.

When the blade is driven by the wind force to rotate the main shaft, the disc cam placed on the main shaft rotates in the horizontal plane, and the ball, the force rod and the hollow rivet reciprocate horizontally along the guide rod under the action of the spring, thereby driving The piezoelectric vibrator connected in series by solid rivets and hollow rivets performs reciprocating bending deformation and converts mechanical energy into electrical energy.

In the above working process, the deformation rules of the piezoelectric vibrators in series are consistent, synchronous power generation, and its deformation is always subject to the curve shape of the disc cam, so regardless of the speed, the maximum deformation of each piezoelectric vibrator is the same, thus obtaining Larger power generation and higher reliability.

Features and advantages of the present invention: ① Use the disc cam to simultaneously excite multiple sets of piezoelectric vibrators in series to generate electricity synchronously, and the power generation and power supply energy is strong; ② The force rod is always in contact with the curved surface of the disc cam through the ball, which can avoid deformation of the piezoelectric vibrator It is too large and damaged, so it has high reliability and no excitation impact and noise; ③The blades are installed on the vertical main shaft, which can collect wind energy from all directions to generate electricity, and the wind direction is highly adaptable.

Description of drawings

Fig. 1 is a schematic diagram of the structure and principle of a self-powered device in a preferred embodiment of the present invention;

Fig. 2 is the A-A sectional view of Fig. 1;

Fig. 3 is an enlarged view of part I of Fig. 1;

Fig. 4 is an enlarged axial view of the spindle of the present invention.

Detailed ways

The frame 1 is provided with a transduction chamber 1a and an excitation chamber 1b, the end of the transduction chamber 1a is fitted with an end cover 7 through screws, and the upper wall 1c of the excitation chamber 1b is mounted with a flange 2 embedded with a bearing 3 through screws 1. A guide sleeve 5 is inlaid on the side wall 1d, and a bearing 3 is embedded on the lower wall 1e; the main shaft 4 is installed on the frame 1 through the two bearings 3, and the part inside the excitation cavity 1b is provided with a The disk cam 1 4a and disk cam 2 4b of the transducer 8 are equipped with blades 6 on the outer shaft end; , a solid rivet 13, a hollow rivet 12 and a force rod 14; the piezoelectric vibrator 11 is formed by bonding a bowl-shaped metal substrate 11a and an annular piezoelectric chip 11b; the base 10 is fixed on the end cover 7 by screws, and the guide rod The end cap of 9 is pressed on the end cover 7; the application rod 14 is set in the guide hole of the guide sleeve 5, and the pressure block 14a at the end is placed in the excitation cavity 1b; the spring 16 is sleeved on the application rod 14, And be pressed between the pressure block 14a of guide sleeve 5 and guide rod 14 ends, spring 16 will press the ball 15 embedded on the described pressure block 14a on the disk cam-4a or disc cam on the main shaft 4 by pressure block 14a Cam II 4b surface.

According to the structure of the piezoelectric generator of the present invention, the ball 15 inlaid on the pressure block 14a at the end of the force applying rod 14 is always pushed by the spring 16 against the surfaces of the disc cams 4a and 4b on the main shaft 4, so that the piezoelectric vibrator 11 The law of deformation and the maximum amount of deformation are determined by the curved surface shape and eccentricity e of the disc cams 4a and 4b. In order to ensure that the piezoelectric wafer 11b of the piezoelectric vibrator 11 will not be damaged due to excessive deformation, the maximum eccentricity of the disc cams 4a and 4b should be determined by the following formula: e _max =2δE _total (nE _single ), where δ is the piezoelectric vibrator 11 is the maximum unidirectional deformation that can be tolerated. E _{is always} the energy output by the generator, E is the energy produced by a _single piezoelectric vibrator for one reciprocating bending deformation, and n is the number of transducers 8 .

When the blade 6 drives the main shaft 4 to rotate due to the wind force, the disc cams 4a and 4b placed on the main shaft 4 rotate in the horizontal plane, and the ball 15, the force rod 14 and the hollow rivet 12 move along the guide shaft under the action of the spring 16. The rod 9 reciprocates in the horizontal direction, thereby driving the piezoelectric vibrator 11 riveted in series by the solid rivet 13 and the hollow rivet 12 to perform reciprocating bending deformation: when the disc cam 4a or 4b rotates and makes the ball 15 contact with its lift surface, The spring 16 is compressed, and the disc cam 4a or 4b forces the piezoelectric vibrators 11 in series to deform toward each other through the ball 15, the force rod 14, the solid rivet 13 and the hollow rivet 12, which is an active excitation process; on the contrary, when When the cam wheel 4a or 4b rotates and makes the ball 15 contact with its return surface, the spring 16 will elongate under the action of its own elastic force, and the disc cam 4a or 4b will pass through the ball 15, the force rod 14, the solid rivet 13 and the hollow rivet 12. The piezoelectric vibrators 11 connected in series are forced to deform in the direction away from each other, which is a passive reset process. With the continuous rotation of the main shaft 4, the piezoelectric vibrators 11 connected in series will be alternately compressed and stretched, thereby converting mechanical energy into electrical energy.

In the above-mentioned active excitation and passive reset process, the deformation rules of the piezoelectric vibrators 11 in series are consistent, generate electricity synchronously, and their deformation is always subject to the curve shape of the disc cams 4a and 4b, so regardless of the speed, each piezoelectric vibrator The maximum deformation of the vibrator 11 is the same, so as to obtain greater power generation and higher reliability.

Claims (2)

1. A high-power rotary piezoelectric wind-driven generator with disk cam excitation and positioning, characterized in that: the frame is provided with a plurality of transduction chambers and an excitation chamber, and the ends of the transduction chambers are installed with end caps through screws. Cover, the upper wall of the excitation chamber is installed with a flange with bearings embedded through screws, the side wall is embedded with guide sleeves, and the lower wall is embedded with bearings; the main shaft is installed on the frame through bearings, and the part on the inside of the excitation chamber There is a disk cam for exciting the transducer, and blades are installed on the external shaft end; the transducer is composed of a base that is set on the guide rod and riveted in series with each other, a bowl-shaped piezoelectric vibrator, a solid rivet, a hollow rivet and The force rod is formed; the piezoelectric vibrator is bonded by a bowl-shaped metal substrate and a ring-shaped piezoelectric chip; the base is fixed on the end cover by screws, and the end cap of the guide rod is pressed on the end cover; the force rod is sleeved on the guide rod. The guide hole of the sleeve and the pressing block at its end are placed in the excitation cavity; the spring is sleeved on the force rod and pressed between the guide sleeve and the pressing block at the end of the guide rod, and the spring will be inlaid through the pressing block. Balls on the pressure block press against disc cam surfaces on the spindle. 2. The high-power rotary piezoelectric wind-driven generator with disc cam excitation and limit according to claim 1, characterized in that: the maximum eccentricity of the disc cam should be determined by the following formula: e _max =2δE _total /(nE _Single ), where δ is the maximum one-way deformation that the piezoelectric vibrator can bear, E _always is the energy output by the generator, E _single is the energy generated by a single piezoelectric vibrator for one reciprocating bending deformation, and n is the energy conversion number of devices.