CN107181426A - One kind vibration, the compound piezoelectric energy-capturing battery of the temperature difference - Google Patents

Abstract

The invention relates to a vibration and temperature difference composite piezoelectric energy-harvesting battery, comprising: an upper battery case, a lower battery case, an upper spring, a lower spring, an upper piezoelectric cantilever beam, a lower piezoelectric cantilever beam, a transmission shaft, and a disc-shaped heating element. Bimetals and cooling towers. Wherein: the upper battery case senses the heat from the external environment and transfers it to the disc-shaped thermal bimetal sheet, causing it to deform downward at the critical point of temperature, driving the drive shaft to move downward, and the upper piezoelectric cantilever beam is released to generate vibration. When the lower piezoelectric cantilever is impacted, it also vibrates under the action of the lower spring. When the dish-shaped thermal bimetal is cooled by the cooling material of the cooling tower, the deformation is restored, the transmission shaft moves upward, and the upper and lower piezoelectric cantilever beams vibrate again at this time. The device can also generate electricity by using environmental vibrations. When the device is used in micro-electro-mechanical devices, it can meet the power supply requirements for micro-electro-mechanical devices, and has the advantages of simple structure, strong environmental adaptability, high energy harvesting efficiency, and easy integration.

Description

A vibration and temperature difference composite piezoelectric energy harvesting battery

technical field

The invention belongs to the field of piezoelectric power generation, and in particular relates to a vibration and temperature difference composite piezoelectric energy harvesting battery.

Background technique

In recent years, with the application of micro-electro-mechanical devices (MEMS) in wireless sensor network nodes, military weapons, aerospace, medical and other fields, the power supply of micro-electro-mechanical devices has attracted widespread attention. Traditional chemical batteries have problems such as limited battery life, difficulty in integration, poor environmental adaptability, and pollution. Traditional line power supply cannot be applied to micro-electromechanical devices in specific occasions. Therefore, more and more attention has been paid to self-powered equipment. Equipment such as solar power generation, electromagnetic power generation, temperature difference power generation, vibration power generation, and wind power generation have entered the practical stage, but each has its own advantages and disadvantages. Among them, the self-powered device that utilizes environmental vibration to drive piezoelectric generating units to generate electricity has become a hot research direction due to its advantages of easy integration, strong environmental adaptability, and no electromagnetic interference. However, the existing vibration energy harvesting device can only generate electricity using environmental vibrations. When the micro-electromechanical equipment on which the vibration energy harvesting device is arranged does not vibrate, it cannot generate electricity normally. Therefore, there is an urgent need for a self-power supply that can simultaneously use multiple environmental energies to generate electricity. device.

Contents of the invention

In order to solve the problem that the current piezoelectric energy harvesting device using vibration can only generate electricity by using the vibration of a single environment, a vibration and temperature difference composite piezoelectric energy harvesting battery is proposed. The vibration and temperature difference composite piezoelectric energy harvesting battery includes an upper battery casing, a lower battery casing, an upper spring, a lower spring, an upper piezoelectric cantilever beam, a lower piezoelectric cantilever beam, a transmission shaft, a disc-shaped thermal bimetal sheet and a cooling tower . The upper battery casing is connected with the lower battery casing to form a closed and sealed cavity for the battery. The upper battery casing is used to sense the external temperature, and the temperature is transmitted to the disc-shaped thermal bimetal to make the temperature rise continuously. When the deformation critical point is reached, the disc-shaped The thermal bimetal sheet deforms downward, driving the drive shaft to move downward, the initial state is released by the upper piezoelectric cantilever and moves downward, the piezoelectric cantilever vibrates up and down, and the lower piezoelectric cantilever is affected by the disc-shaped thermal bimetal The plate impacts and moves downward with the cooling tower, and the piezoelectric cantilever beam vibrates up and down accordingly. The disc-shaped thermal bimetal is attached to the cooling tower, and the cooling liquid in the cooling tower will cause the temperature of the disc-shaped thermal bimetal to drop. When the temperature drops to a certain level, the disc-shaped thermal bimetal will recover its deformation and move upward. The cantilever beam is released to vibrate, and the upper piezoelectric cantilever beam will also vibrate when it is impacted by the transmission shaft. At the same time, the device can also use environmental vibration to generate electricity. Both the upper spring and the lower spring can sensitively sense the vibration of the external environment, and drive the piezoelectric cantilever beam connected to it to vibrate. The use of temperature difference and vibration to generate electricity increases the way of energy capture and improves the efficiency of energy capture. When it is arranged in a suitable micro-electro-mechanical device, it can meet the power demand of the micro-electro-mechanical device, and has the advantages of simple structure, strong environmental adaptability, high energy harvesting efficiency, and easy integration.

In order to achieve the above object, the present invention adopts the following technical solutions:

The present invention is a vibration and temperature difference composite piezoelectric energy harvesting battery, comprising: an upper battery casing (1), a lower battery casing (2), an upper spring (3), a lower spring (4), an upper piezoelectric cantilever beam (5 ) and the lower piezoelectric cantilever beam (6), transmission shaft (7), which is characterized in that it also includes a disc-shaped thermal bimetallic sheet (8) and a cooling tower (9), wherein: the upper battery case (1) and the lower The battery case (2) is a cylindrical shell with a bottom, a circular sinking groove is arranged in the middle of the inner surface of the bottom of the cylindrical shell, and a circumferential sinking groove is arranged on the opening surface of the upper side of the shell to form a shoulder; the upper battery The casing (1) is a good conductor of heat, and the lower battery casing (2) is a poor conductor of heat; the lower surface of the upper battery casing (1) is connected to the upper surface of the lower battery casing (2) to form a battery sealed cavity; Both the upper spring (3) and the lower spring (4) are coil springs, the upper spring (3) is installed in the circular sinker of the upper battery case (1), and the lower spring (4) is installed in the circular sinker of the lower battery case (2). In the groove; the upper piezoelectric cantilever beam (5) is composed of an elastic substrate (51), a fan-shaped piezoelectric sheet (52) and a mass block (53), and the elastic substrate (51) is composed of a wafer and some arrays outside the wafer. The fan-shaped cantilever beam is composed of a fan-shaped piezoelectric sheet (52) pasted on the upper surface of the fan-shaped cantilever beam, and a mass block (53) is pasted on the upper surface of the fan-shaped cantilever beam outer edge; the lower piezoelectric cantilever beam (6) and the upper piezoelectric cantilever beam ( 5) are the same components; the transmission shaft (7) is a hollow shaft; the disc-shaped thermal bimetallic sheet (8) is a disc-shaped sheet member made of different metal materials from the upper and lower layers, wherein the metal material of the upper layer The coefficient of thermal expansion is much greater than that of the underlying metal, and a through hole is arranged in the center of the disc-shaped sheet; the upper surface of the transmission shaft (7) is in contact with the lower surface of the upper piezoelectric cantilever beam (5), and the lower end is installed on the disc-shaped thermal cantilever with an interference fit. In the through hole of the bimetal sheet (8), the upper surface of the upper piezoelectric cantilever beam (5) is connected to the lower end of the upper spring (3); the cooling tower (9) is composed of two connected cylindrical hollow shells, the upper The volume of the cylindrical shell is much larger than the volume of the lower cylindrical shell and the upper surface of the upper cylindrical shell is a concave spherical surface; the inside of the cooling tower (9) shell is filled with cooling liquid; the upper end of the cooling tower (9) There is a gap with the disc-shaped thermal bimetal (8), the lower end is connected to the upper surface of the lower piezoelectric cantilever (6), and the lower surface of the piezoelectric cantilever (6) is connected to the upper end of the lower spring (4).

The disc-shaped thermal bimetal (8) can be replaced by a disc-shaped metal sheet made of a shape memory alloy.

When working, when the environment of the micro-electromechanical equipment arranged by the vibration and temperature difference composite piezoelectric energy harvesting battery is heated, the upper battery shell will transfer the external temperature to the disc-shaped thermal bimetallic sheet to make the temperature rise continuously, reaching the deformation critical point , the disc-shaped thermal bimetal deforms downward, driving the drive shaft to move downward, and the upper piezoelectric cantilever is released in the initial state and moves downward, the piezoelectric cantilever vibrates up and down, and the lower piezoelectric cantilever is affected by The dish-shaped thermal bimetal impacts and moves downward together with the cooling tower, and the piezoelectric cantilever beam vibrates up and down accordingly. The disc-shaped thermal bimetal is attached to the cooling tower, and the cooling liquid in the cooling tower will cause the temperature of the disc-shaped thermal bimetal to drop. When the temperature drops to a certain level, the disc-shaped thermal bimetal will recover its deformation and move upward. The cantilever beam is released to vibrate, and the upper piezoelectric cantilever beam will also vibrate when it is impacted by the transmission shaft. At the same time, the device can also use environmental vibration to generate electricity. Both the upper spring and the lower spring can sensitively sense the vibration of the external environment, and drive the piezoelectric cantilever beam connected to it to vibrate. The use of temperature difference and vibration to generate electricity increases the way of energy capture and improves the efficiency of energy capture. When it is arranged in a suitable micro-electro-mechanical device, it can meet the power demand of the micro-electro-mechanical device, and has the advantages of simple structure, strong environmental adaptability, high energy harvesting efficiency, and easy integration.

Description of drawings

Figure 1 is a schematic diagram of the assembly relationship of a vibration and temperature difference composite piezoelectric energy harvesting battery of the present invention.

Fig. 2 is a sectional view of an initial state of a vibration and temperature difference composite piezoelectric energy harvesting battery of the present invention.

Fig. 3 is a cross-sectional view of a vibration and temperature difference composite piezoelectric energy harvesting battery of the present invention in a thermally deformed state.

detailed description

Referring to Fig. 1, Fig. 2 and Fig. 3, a vibration and temperature difference composite piezoelectric energy harvesting battery of the present invention comprises: an upper battery case (1), a lower battery case (2), an upper spring (3), a lower spring (4 ), the upper piezoelectric cantilever beam (5) and the lower piezoelectric cantilever beam (6), the transmission shaft (7), is characterized in that it also includes a dish-shaped thermal bimetallic sheet (8) and a cooling tower (9), wherein: the The upper battery case (1) and the lower battery case (2) are both cylindrical shells with a bottom, a circular sinking groove is arranged in the middle of the inner surface of the bottom of the cylindrical shell, and a circumferential sinking groove is arranged on the opening surface of the upper side of the shell A shoulder is formed; the upper battery casing (1) is a good conductor of heat, and the lower battery casing (2) is a poor conductor of heat; the lower surface of the upper battery casing (1) and the upper surface of the lower battery casing (2) Welding forms the sealed chamber of the battery; the upper spring (3) and the lower spring (4) are coil springs, the upper spring (3) is installed in the circular sinker of the upper battery casing (1), and the lower spring (4) is installed In the circular sinker of the lower battery casing (2); the upper piezoelectric cantilever beam (5) is composed of an elastic substrate (51), a fan-shaped piezoelectric sheet (52) and a mass (53), and the elastic substrate (51) is composed of The disc and a plurality of fan-shaped cantilever beams arrayed outside the disc are composed, the fan-shaped piezoelectric sheet (52) is pasted on the upper surface of the fan-shaped cantilever beam, and the mass block (53) is pasted on the outer edge upper surface of the fan-shaped cantilever beam; the lower piezoelectric cantilever beam ( 6) It is the same component as the upper piezoelectric cantilever beam (5); the transmission shaft (7) is a hollow shaft; the disc-shaped thermal bimetallic sheet (8) is a disc made of different metal materials on the upper and lower layers Shaped sheet member, wherein the thermal expansion coefficient of the metal material of the upper layer is much greater than that of the lower layer metal, and a through hole is arranged in the center of the disc-shaped sheet; the upper surface of the transmission shaft (7) is in contact with the lower surface of the upper piezoelectric cantilever beam (5), The interference fit of the lower end is installed in the through hole of the disc-shaped thermal bimetal (8), and the upper surface of the upper piezoelectric cantilever beam (5) is welded to the lower end of the upper spring (3); the cooling tower (9) is composed of two connected Composed of a cylindrical hollow shell, the volume of the upper cylindrical shell is much larger than that of the lower cylindrical shell and the upper surface of the upper cylindrical shell is a concave spherical surface; the inside of the shell of the cooling tower (9) is filled with cooling liquid There is a gap between the upper end of the cooling tower (9) and the disc-shaped thermal bimetal sheet (8), the lower end is welded on the upper surface of the lower piezoelectric cantilever beam (6), and the lower surface of the piezoelectric cantilever beam (6) is welded to the lower spring (4) Upper end.

The disc-shaped thermal bimetal (8) can be replaced by a disc-shaped metal sheet made of a shape memory alloy.

When working, when the environment of the micro-electromechanical equipment arranged by the vibration and temperature difference composite piezoelectric energy harvesting battery is heated, the upper battery shell will transfer the external temperature to the disc-shaped thermal bimetallic sheet to make the temperature rise continuously, reaching the deformation critical point , the disc-shaped thermal bimetal deforms downward, driving the drive shaft to move downward, and the upper piezoelectric cantilever is released in the initial state and moves downward, the piezoelectric cantilever vibrates up and down, and the lower piezoelectric cantilever is affected by The dish-shaped thermal bimetal impacts and moves downward together with the cooling tower, and the piezoelectric cantilever beam vibrates up and down accordingly. The disc-shaped thermal bimetal is attached to the cooling tower, and the cooling liquid in the cooling tower will cause the temperature of the disc-shaped thermal bimetal to drop. When the temperature drops to a certain level, the disc-shaped thermal bimetal will recover its deformation and move upward. The cantilever beam is released to vibrate, and the upper piezoelectric cantilever beam will also vibrate when it is impacted by the transmission shaft. At the same time, the device can also use environmental vibration to generate electricity. Both the upper spring and the lower spring can sensitively sense the vibration of the external environment, and drive the piezoelectric cantilever beam connected to it to vibrate. The use of temperature difference and vibration to generate electricity increases the way of energy capture and improves the efficiency of energy capture. When it is arranged in a suitable micro-electro-mechanical device, it can meet the power demand of the micro-electro-mechanical device, and has the advantages of simple structure, strong environmental adaptability, high energy harvesting efficiency, and easy integration.

Claims (2)

1. one kind vibration, the compound piezoelectric energy-capturing battery of the temperature difference, including：Upper battery case (1), lower battery case (2), upper spring (3), lower spring (4), upper piezoelectric cantilever (5) and lower piezoelectric cantilever beam (6), power transmission shaft (7), it is characterised in that also including dish Thrermostatic bimetal-plate (8) and cooling tower (9), wherein：The upper battery case (1) and lower battery case (2) are the cylinder bottom of with Shape housing, cylinder cover bottom inner surface center is disposed with the circumferential deep gouge formation one of open surfaces arrangement one on the upside of circular deep gouge, housing Shoulder；Upper battery case (1) lower surface is connected composition cell sealing cavity with lower battery case (2) upper surface；On described Spring (3) and lower spring (4) are helical spring, and upper spring (3) is arranged in the circular deep gouge of upper battery case (1), lower spring (4) it is arranged in the circular deep gouge of lower battery case (2)；The upper piezoelectric cantilever (5) is by elastic base plate (51), fan-shaped piezoelectric patches (52) constituted with mass (53), elastic base plate (51) some fan-shaped cantilever beams of array outside disk and disk are constituted, it is fan-shaped Piezoelectric patches (52) is pasted onto fan-shaped cantilever beam upper surface, and mass (53) is pasted onto fan-shaped cantilever beam outer rim upper surface；Under described Piezoelectric cantilever (6) is identical components with upper piezoelectric cantilever (5)；The power transmission shaft (7) is a hollow shaft；The dish heat is double It by levels is the dish-shaped sheet members that are made of different metal material that sheet metal (8), which is, its metal material thermal expansion at the middle and upper levels Coefficient is much larger than the thermal coefficient of expansion of lower metal, and dish-shaped thin slice center is disposed with through hole；Power transmission shaft (7) upper surface with it is upper Piezoelectric cantilever (5) lower surface is contacted, and lower end interference fit is arranged in dish-shaped thrermostatic bimetal-plate (8) through hole, upper piezoelectric cantilever Beam (5) upper surface is connected to spring (3) lower end；The cooling tower (9) is made up of two cylindrical, hollow communicated housings, on Cylindrical housings volume is shaped as the sphere of indent much larger than lower cylindrical housings volume and upper cylindrical housings upper surface；It is described Cooling tower (9) enclosure interior is full of cooling liquid；Gap is left in cooling tower (9) upper end with dish-shaped thrermostatic bimetal-plate (8), under End is connected to lower piezoelectric cantilever beam (6) upper surface, and piezoelectric cantilever (6) lower surface is connected to lower spring (4) upper end.

2. a kind of vibration, the compound piezoelectric energy-capturing battery of the temperature difference according to claim 1, it is characterised in that：The dish heat The dish-shaped sheet metal that bimetal leaf (8) can be made up of marmem is replaced.