Stepped magnetostrictive vibration energy collector with compensation block

Abstract

The invention relates to a stepped magnetostrictive vibration energy collector with a compensation block. The collector comprises an L-shaped beam, a bias magnet, a stepped magnetostrictive composite structure and a compensation block, a stepped magnetostriction composite structure is fixed in the middle of the inner side of a vertical beam of the L-shaped beam; the bias magnet is placed at the far end of the horizontal beam of the L-shaped beam; the stepped magnetostriction composite structure comprises a stepped plate, a magnetostriction layer and a pickup coil; and the magnetostrictive layer is a magnetostrictive sheet. The device is better in mechanical performance, lower in cost and high in mechanical-magnetic conversion efficiency, and miniaturization and light weight of the device are facilitated; higher voltage application can be output under the condition of smaller amplitude, the prospect is wider, and the requirement of production economy is better met.

Description

Technical Field

[0001] The invention relates to the field of transient vibration energy collection, and in particular to a magnetostrictive energy collector capable of collecting transient vibration energy generated by finger flicking. Background Art

[0002] As electronic devices become more intelligent and integrated, and their functions become richer, more and more electronic components are needed per unit space, and energy consumption will continue to increase. Therefore, the power supply problem has become a major problem in the design of these devices and has attracted the attention of more and more researchers. People are working hard to explore the energy that can be used from the surrounding environment, including light energy, heat energy, and sound wave vibration energy. In recent years, vibration energy harvesting technology has received widespread attention. It can convert the mechanical energy of various vibrations of the human body into electrical energy to achieve continuous energy supply for wearable devices, and is expected to solve the problems of large mass and volume, short life, and environmental pollution in traditional battery power supply. Vibration energy harvesting technology is mainly divided into electromagnetic, piezoelectric, and magnetostrictive. Electromagnetic generally has a bulky pickup coil with a large volume; piezoelectric materials are brittle and easily damaged after long-term work, and charge leakage is prone to occur. Because of their capacitive properties, they have a very high output impedance. Among them, magnetostrictive materials, with their unique force-magnetic coupling effect, can convert external stress / strain into magnetic changes, and then collect electrical energy in the coil, ultimately achieving fast and efficient energy collection. Compared with electromagnetic, piezoelectric and other energy collection technologies, they have advantages in applicable frequency bands, conversion efficiency, energy density and other aspects.

[0003] The current magnetostrictive vibration energy harvesting technology still faces many challenges such as low material pressure resistance and complex structural design. For example: Document No. 10.1016 / j.ijmecsci.2017.03.032 A multi-impact variable frequency magnetostrictive transducer for collecting finger tapping energy. This paper uses iron-gallium alloy as the core component and designs a multi-tooth structure to complete the conversion from low frequency to high frequency, realizing the collection of transient vibration energy from finger tapping. However, the iron-gallium alloy is brittle and expensive, and the multi-tooth structure design is relatively complex, which is not conducive to large-scale production and popularization. Summary of the invention

[0004] The purpose of the present invention is to address the deficiencies in the current technology. The present invention proposes a stepped magnetostrictive vibration energy collector with a compensation block. The collector is a new structure of a stepped type + compensation block. On the basis of increasing the vibration frequency of the energy collector, it also takes into account the increase in the length of the free end. This innovative design fully improves the output voltage of the energy collector. The present invention has the advantages of simple structure, low cost, high mechanical strength, large output signal, etc., and is extremely suitable for the field of human body vibration energy collection such as finger plucking.

[0005] The technical solution adopted by the present invention to solve its technical problem is: A step-type magnetostrictive vibration energy collector with a compensation block, the collector comprises an L-shaped beam, a bias magnet, a step-type magnetostrictive composite structure and a compensation block; the step-type magnetostrictive composite structure is fixed to the middle of the inner side of the vertical beam of the L-shaped beam; the bias magnet is placed at the far end of the horizontal beam of the L-shaped beam; The step-type magnetostrictive composite structure comprises a step-type plate, a magnetostrictive layer, and a pickup coil; the step-type plate is a right-angle Z-shaped plate, comprising a main horizontal plate, a free end horizontal plate, and a vertical connecting plate; the magnetostrictive layer is bonded to the main horizontal plate of the step-type plate by epoxy resin glue; the pickup coil is wound on the magnetostrictive layer and the main horizontal plate; the compensation block is clamped at the free end of the step-type magnetostrictive composite structure; The width of the magnetostrictive layer is the same as that of the main transverse plate, and the length is 50-70% of that of the main transverse plate; The main transverse plate is parallel to the horizontal beam of the L-beam; The magnetostrictive layer is a magnetostrictive sheet made of iron-cobalt-vanadium alloy (Fe49-Co49-V2); the size is 45 mm × 15 mm, and the thickness ranges from 0.1 to 0.3 mm; The material of the step-shaped plate is stainless steel with a thickness ranging from 0.3 to 0.5 mm, wherein the main horizontal plate has a size of 85 mm × 15 mm, the free end horizontal plate has a size of 20 mm × 15 mm, and the vertical connecting plate has a size of 15 mm × 15 mm, which together form a step-shaped structure; The pickup coil is made of insulated copper enameled wire; the length of the coil is the same as the magnetostrictive layer; The compensation block is made of pure aluminum, with a size of 15mm×15mm×2.6mm, and a clamping seam with a width of 0.3~0.5mm and a lateral depth of 10mm on the left side; The bias magnet is made of N35 neodymium iron boron permanent magnet, with a size of 15mm×15mm×5mm; the specific position is 70% of the length of the horizontal beam; The dimensions of the horizontal beam of the L-shaped beam are 80mm×15mm×5mm, and the dimensions of the vertical beam are 40mm×15mm×5mm; The pickup coil has 1500 turns and a diameter ranging from 0.15 to 0.25 mm; The essential features of the present invention are: The magnetostrictive vibration energy harvester in current technology generally uses iron-gallium alloy as the core component, but the mechanical properties of iron-gallium alloy are poor and the cost is high, which is not conducive to large-scale production and popularization. At the same time, the energy collector structure design is relatively complex and has more additional losses. These factors lead to low energy collection efficiency of the device. For the field of transient vibration energy collection of the human body such as finger flicking, low energy collection efficiency will lead to a decrease in the output signal, so it is not suitable for the field of transient vibration energy collection.

[0006] The present invention adopts iron-cobalt-vanadium alloy with better mechanical properties as the core component and designs a stepped structure with a compensation block. Under transient excitation such as finger flicking, the collector vibrates at high frequency, converting low-frequency transient vibration into high-frequency free vibration, thereby achieving a high-efficiency improvement in energy collection efficiency. It is extremely suitable for the field of transient vibration energy collection.

[0007] The main principle is: when transient excitation is applied to the compensation block of the step-type magnetostrictive energy collector, the connected magnetostrictive layer will undergo continuous free oscillation and swing, achieving continuous high-frequency free oscillation and swing. The bending deformation generated during the vibration of the magnetostrictive layer causes the magnetization state inside the magnetostrictive layer to change, that is, the magnetic permeability changes, which ultimately leads to a change in magnetic flux. According to Faraday's law of electromagnetic induction, the winding coil generates an induced voltage.

[0008] The beneficial effects of the present invention are: 1. The core element of the energy collector of the present invention is iron-cobalt-vanadium alloy, which has better mechanical properties and lower cost than iron-gallium alloy. Improved mechanical properties correspond to longer service life, no aging problems, more reliable working performance, high mechanical-magnetic conversion efficiency, and is conducive to miniaturization and lightweight of devices. It can output higher voltage applications under smaller amplitude conditions, has broader prospects, and is more in line with the requirements of production economy.

[0009] 2. In order to improve the energy collection efficiency, the existing magnetostrictive vibration energy collector adopts a complex structural design, but the complex structure brings additional mechanical loss. Compared with other existing magnetostrictive vibration energy collectors, the magnetostrictive energy collector of the present invention is designed with a stepped structure, which has a simple overall structure, less additional mechanical loss, and a higher output voltage.

[0010] 3. In order to further adapt to the transient vibration energy collection in human activities, the present invention designs a compensation block according to the size of the first section of the finger, aiming to achieve efficient energy collection of finger activities. The maximum output voltage of the improved magnetostrictive energy collector is 1520mV under finger excitation, which is significantly increased by 220% compared with the maximum output voltage of the literature: A multi-impact variable frequency magnetostrictive transducer for collecting finger tapping energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 This is a schematic diagram of the structure of a stepped magnetostrictive vibration energy harvester with a compensation block. Figure 2 for Figure 1 Front view Figure 3 Schematic diagram of the magnetostrictive layer Figure 4 Schematic diagram of the stepped plate Figure 5 Schematic diagram of the compensation block Figure 6 This is the output voltage diagram of the energy harvester when the finger is flicked; In the figure: 1-L-shaped beam; 2-step plate; 3-magnetostrictive layer; 4-pickup coil; 5-bias magnet; 6-compensation block; DETAILED DESCRIPTION

[0012] This stepped magnetostrictive vibration energy harvester with a compensation block realizes vibration energy harvesting by using the inverse magnetostrictive effect and the law of electromagnetic induction. When a transient excitation is applied to the compensation end of the structure, the connected magnetostrictive layer will undergo continuous free oscillation swing. The bending deformation generated during the vibration of the magnetostrictive layer causes the magnetization state inside the magnetostrictive layer to change, that is, the magnetic permeability changes, which ultimately leads to a change in the magnetic flux. According to Faraday's law of electromagnetic induction, the winding coil will induce a changing magnetic field and generate an induced voltage. By integrating the inverse magnetostrictive effect and the law of electromagnetic induction, the energy harvester can efficiently harvest the energy of transient vibrations and convert it into an output voltage.

[0013] The invention is further described in detail below in conjunction with the figures. This embodiment is only a specific description of the invention and is not to be regarded as limiting the scope of protection.

[0014] The structure of the stepped magnetostrictive vibration energy collector with a compensation block described in the present invention is as follows: Figure 1 As shown, the collector includes an L-shaped beam 1, a bias magnet 5, a stepped magnetostrictive composite structure and a compensation block 6; the stepped magnetostrictive composite structure is fixed to the middle of the inner side of the vertical beam of the L-shaped beam 1; the bias magnet 5 is placed at the far end of the horizontal beam of the L-shaped beam 1; The dimensions of the horizontal beam of the L-shaped beam are 80mm×15mm×5mm, and the dimensions of the vertical beam are 40mm×15mm×5mm.

[0015] The step-type magnetostrictive composite structure comprises a step-type plate 2, a magnetostrictive layer 3, and a pickup coil 4; the step-type plate 2 is a right-angle Z-shaped plate, comprising a main transverse plate 21, a free end transverse plate 22, and a vertical connecting plate 23; the magnetostrictive layer 3 is bonded to the main transverse plate 21 of the step-type plate by epoxy resin glue; the pickup coil 4 is evenly wound on the magnetostrictive layer 3 and the main transverse plate 21; and finally, the compensation block 6 is clamped at the free end of the step-type magnetostrictive composite structure; The width of the magnetostrictive layer 3 is the same as that of the main transverse plate 21, and the length is 50-70% of that of the main transverse plate; (53% in this embodiment); the main transverse plate 21 is parallel to the horizontal beam of the L-shaped beam 1; The magnetostrictive layer is a magnetostrictive sheet made of iron-cobalt-vanadium alloy (Fe49-Co49-V2); the size is 45 mm×15 mm, and the thickness ranges from 0.1 to 0.3 mm (the thickness used in this embodiment is 0.2 mm). Figure 3 As shown; The material of the step-shaped plate 2 is stainless steel, with a thickness range of 0.3-0.5 mm (the thickness used in this embodiment is 0.4 mm), wherein the main horizontal plate 21 has a size of 85 mm × 15 mm, the free end horizontal plate 22 has a size of 20 mm × 15 mm, and the vertical connecting plate 23 has a size of 15 mm × 15 mm, which together form a step-shaped structure. Figure 4 As shown; The pickup coil 4 is made of insulated copper enameled wire, with 1500 turns and a diameter ranging from 0.15 to 0.25 mm (the thickness used in this embodiment is 0.2 mm); the length of the coil is the same as the magnetostrictive layer; The compensation block 6 is made of pure aluminum block, with a size of 15 mm×15 mm×2.6 mm, and a clamping gap with a width of 0.4 mm and a lateral depth of 10 mm is opened on the left side.

[0016] The bias magnet 5 is made of N35 neodymium iron boron permanent magnet, and its size is 15 mm×15 mm×5 mm; the specific position (ie, the left side of the bias magnet 5) is at 70% of the length of the horizontal beam.

[0017] The step-type magnetostrictive vibration energy collector with compensation block is mainly used in the field of transient vibration energy collection such as finger flicking. The energy collector is supported by an L-shaped beam, is light in weight, and can be placed on the ground or on a test bench without a fixed position. The core components inside the collector: the compensation block of the step-type magnetostrictive composite structure with compensation block is used as the application end; The method of use includes the following steps: The experimenters were required to apply different forces with their fingers, move the collector at intervals, and use a laser displacement sensor to measure the displacement of the right end of the composite structure after a transient impact. The data acquisition card was connected to the computer, and the voltage signal generated by the energy collector was processed by the corresponding software to obtain an accurate voltage output.

[0018] At this time, the process of the energy collector is as follows: transient excitation is applied to the compensation end of the step-type magnetostrictive energy collector, and the connected magnetostrictive layer will undergo continuous free oscillation swing, achieving continuous high-frequency free oscillation swing. The bending deformation generated during the vibration of the magnetostrictive layer causes the magnetization state inside the magnetostrictive layer to change, that is, the magnetic permeability changes, which ultimately leads to a change in the magnetic flux. According to Faraday's law of electromagnetic induction, the coil wound around the magnetostrictive layer will induce the changing magnetic flux, thereby generating an induced voltage. The permanent magnet provides a bias magnetic field, which will further excite the magnetostrictive layer to produce more magnetic domains, increasing the change in magnetic flux.

[0019] The protocols and software involved in the present invention are all well-known technologies.

[0020] Data Acquisition Card (DAQ card). DAQ card, also known as acquisition card, is a hardware device. This device is responsible for collecting the voltage analog signal output by the energy harvester after being impacted, and converting it into a digital signal for transmission to the computer for subsequent processing and analysis. The acquisition card is usually connected to the computer through interfaces such as PCI, PCI Express, USB, etc., providing efficient data acquisition and analysis capabilities for the experiment.

[0021] The voltage signal generated by the energy collector is connected to the computer through the data acquisition card, and the voltage signal is processed by the DHDAS dynamic signal data acquisition system to obtain an accurate voltage signal. Figure 6 , it can be seen that: the four voltage oscillation attenuation processes generated by the experimenter applying forces of 0.5N, 1N, 1.5N, and 2N in sequence, the applied forces are different, and the voltage amplitudes of the four voltage oscillation attenuations are also different. The voltage generated by the collector gradually rises, and the overall output voltage shows an oscillating attenuation trend, with the maximum output voltage being 1520mV. Compared with the voltage generated in the literature, the voltage increase is huge, which significantly improves the energy collection efficiency. It shows that the stepped magnetostrictive vibration energy harvester with a compensation block can have a good collection effect in the field of transient vibrations such as finger flicking.

[0022] Matters not covered by the present invention are known technologies.

Claims

1. A stepped magnetostrictive vibration energy collector with a compensation block, characterized by The collector comprises an L-shaped beam, a bias magnet, a stepped magnetostrictive composite structure and a compensation block; the stepped magnetostrictive composite structure is fixed at the middle of the inner side of the vertical beam of the L-shaped beam; the bias magnet is placed at the far end of the horizontal beam of the L-shaped beam; The step-type magnetostrictive composite structure comprises a step-type plate, a magnetostrictive layer, and a pickup coil; the step-type plate is a right-angle Z-shaped plate, comprising a main horizontal plate, a free end horizontal plate, and a vertical connecting plate; the magnetostrictive layer is bonded to the main horizontal plate of the step-type plate by epoxy resin glue; the pickup coil is wound on the magnetostrictive layer and the main horizontal plate; the compensation block is clamped at the free end of the step-type magnetostrictive composite structure; The width of the magnetostrictive layer is the same as that of the main transverse plate, and the length is 50-70% of that of the main transverse plate; the length of the coil is the same as that of the magnetostrictive layer; The main cross plate is parallel to the horizontal beam of the L-beam.

2. The step-type magnetostrictive vibration energy collector with compensation block as claimed in claim 1 is characterized by: The magnetostrictive layer is a magnetostrictive sheet made of iron-cobalt-vanadium alloy (Fe49-Co49-V2); the size is 45 mm × 15 mm, and the thickness ranges from 0.1 to 0.3 mm; The material of the stepped plate is stainless steel with a thickness ranging from 0.3 to 0.5 mm, wherein the main horizontal plate has a size of 85 mm×15 mm, the free end horizontal plate has a size of 20 mm×15 mm, and the vertical connecting plate has a size of 15 mm×15 mm, together forming a stepped structure.

3. The step-type magnetostrictive vibration energy collector with compensation block as claimed in claim 1, characterized in that the pickup coil is made of insulated copper enameled wire; The compensation block is made of pure aluminum block with a size of 15mm×15mm×2.6mm. A clamping seam with a width of 0.3-0.5mm and a lateral depth of 10mm is opened on the left side.

4. The step-type magnetostrictive vibration energy collector with compensation block as claimed in claim 1, characterized in that the bias magnet is made of N35 neodymium iron boron permanent magnet, with a size of 15mm×15mm×5mm; the specific position is 70% of the length of the horizontal beam; The dimensions of the horizontal beam of the L-shaped beam are 80mm×15mm×5mm, and the dimensions of the vertical beam are 40mm×15mm×5mm; The pickup coil has 1500 turns and a diameter ranging from 0.15 to 0.25 mm.

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