A micro wearable energy harvesting device based on FPC technology and electromagnetic coupling

Abstract

The invention discloses a micro wearable energy collection device based on FPC technology and electromagnetic coupling, comprising a shell, a planar FPC coil group, a rotating shaft, a rotating wheel, and an energy collection circuit. The device is characterized in that the planar FPC coil group is fixed to the middle of the vertical direction inside the shell perpendicular to the rotating shaft, the planar FPC coil group comprises a first coil, a second coil, a third coil, a fourth coil, a fifth coil, and an FPC substrate covering the upper and lower sides of the coil, the miniaturization and density improvement of the coil are achieved by adopting the FPC technology, the rotating shaft is vertically fixed to the inner wall of the shell through a bearing, the rotating wheel is installed on the outer ring of the bearing and can rotate around the bearing, the rotating wheel comprises a lightweight bracket, 5 square permanent magnets and a counterweight mass block, the low-frequency vibration of the outside world drives the counterweight mass block to swing, the energy collection circuit is fixed to the bottom of the shell, and is connected to the planar FPC coil group through a thin wire to convert weak alternating current into direct current, and the device can realize the collection of vibration energy in the environment and the human body.

Description

Technical Field

[0001] The present invention relates to a micro wearable energy harvesting device based on an FPC process and electromagnetic coupling, belonging to the technical field of wearable energy harvesting. Background Art

[0002] With the development of integrated circuit and internet technologies, a wide variety of wearable devices have emerged in recent years. Through these wearable devices, people can better understand their own conditions and external information. As wearable devices continue to develop, their power consumption is becoming increasingly lower. Harvesting energy from the human body and converting it into electrical energy to power wearable devices has become one of the main solutions to solve the power supply problem of these devices.

[0003] The human body primarily contains kinetic (vibrational) energy, thermal energy, wind energy, acoustic energy, and biochemical energy. Currently, the main methods for harvesting human energy include electromagnetic, piezoelectric, thermoelectric, and biofuel cells. Among the methods for harnessing human energy, inertial (kinetic) energy harvesting offers the highest efficiency. However, traditional inertial (kinetic) energy harvesters are bulky and heavy, making them inconvenient for human movement. Furthermore, miniaturized harvesters suffer from poor planar magnet performance, limited coil turns, and reduced amplitude, resulting in reduced energy harvesting efficiency. Currently, FPC technology is becoming increasingly popular in PCB production. Coils produced using this process have a reduced thickness, compact size, high turn density, and high energy conversion efficiency. Rare earth permanent magnets offer the highest overall performance among known permanent magnet materials, and their use significantly enhances planar magnetic field strength.

[0004] Patent No. CN201621210038.2 discloses a flexible, wearable, temperature-based energy harvesting device based on MEMS technology. This device uses a flexible material as a substrate and utilizes the body's temperature difference as a heat source to generate electricity. The biggest drawback of this method is that the temperature-based power generation is low, less efficient than kinetic energy harvesting solutions, and cannot independently power wearable devices, serving only as an auxiliary power supply.

[0005] Patent No. CN201710205950.1 discloses a wearable self-driven power supply system that collects low-frequency walking energy. This system is based on friction power generation technology and uses the human body, shoe soles and the ground to construct a human power generation device, thereby solving the complex problems of existing human power generation devices. The biggest disadvantage of this method is that its friction layer is the sole of the shoe and any walking surface, which limits the wearing position and affects walking.

[0006] Patent No. CN200880112238.6 discloses a miniature human-powered charger with an axial flux generator, which includes a mechanical transmission device, an axial flux generator, and a charging control module. Its axial flux generator has a stator and two identical rotors, and the planar winding of the stator is made of a multi-layer printed circuit board (PCB). The charger also includes a charging control module for converting the unstable alternating current generated by the generator into a charging DC current. The biggest disadvantage of this method is that its planar winding is implemented with a multi-layer printed circuit board (PCB). Compared with the FPC process, its volume is greatly increased and its portability is poor. Summary of the Invention

[0007] The purpose of the present invention is to develop a micro wearable energy harvesting device based on FPC technology and electromagnetic coupling. The device adopts a rotating structure and uses an eccentric wheel mechanism to convert external low-frequency vibrations into rotational motion. During the rotation process, a square permanent magnet cuts the flat FPC coil group, converting low-frequency vibrations in the human body and its environment into electrical energy, thereby realizing wearable energy harvesting.

[0008] To realize the present invention, the technical solution adopted is: a micro wearable energy harvesting device based on FPC technology and electromagnetic coupling, comprising a housing (1), a planar FPC coil group (2), a rotating shaft (3), a rotating wheel (4), and an energy harvesting circuit (5), characterized in that the planar FPC coil group (2) is fixed to the middle of the vertical direction inside the housing (1) perpendicular to the rotating shaft (3), and the first coil (10), the second coil (11), the third coil (12), the fourth coil (13), and the fifth coil (14) of the planar FPC coil group (2) and an FPC substrate (16) covering the upper and lower sides of the coil (15). The rotating shaft (3) is vertically fixed to the inner wall of the housing (1) through a bearing (8). The rotating wheel (4) is installed on the outer ring of the bearing (8) and can rotate around the bearing (8). The rotating wheel (4) includes a lightweight bracket (9), five square permanent magnets (6) and a counterweight mass block (7). The low-frequency vibration of the outside world drives the counterweight mass block (7) to swing. The energy collection circuit (5) is fixed to the bottom of the housing (1) and is connected to the planar FPC coil group (2) through a thin wire. The rotating wheel (4) swings within a range of 360 degrees with the external low-frequency motion. The rotating wheel (4) is a lightweight bracket (9) made of lightweight material. A counterweight mass block (7) is set at the edge of the rotating wheel (4). The counterweight mass block (7) can be an iron block or a copper block. At the same time, five square permanent magnets (6) are embedded in the rotating wheel (4) at equal intervals. The planar FPC coil group (2) is fixed to the inner side of the bottom of the housing (1), below the rotating wheel (4), and parallel to the lightweight bracket (9). When the rotating wheel (4) swings, the square permanent magnet (6) cuts the planar FPC coil group (2), thereby realizing electromagnetic vibration energy collection.

[0009] The energy collection circuit (5) is fixed on the inner side of the bottom of the housing (1), below the planar FPC coil group (2). Its base material can be a glass fiber PCB or a flexible FPC. It is connected to the planar FPC coil group (2) through a thin wire to achieve conversion of weak alternating current to direct current.

[0010] Beneficial effects of the present invention:

[0011] 1. The present invention adopts flexible FPC to make the coil, which reduces the thickness of the coil and realizes the miniaturization of the device.

[0012] 2. The present invention adopts an eccentric wheel structure to convert external low-frequency vibration into rotational motion, thereby realizing motion form conversion.

[0013] 3. The present invention uses electromagnetic coupling to achieve environmental energy collection. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the overall appearance of a micro wearable energy harvesting device based on FPC technology and electromagnetic coupling according to the present invention;

[0015] Figure 2 This is a cross-sectional view of the internal structure of a micro wearable energy harvesting device based on FPC technology and electromagnetic coupling according to the present invention;

[0016] Figure 3 This is a schematic diagram of the stacked structure of a planar FPC coil assembly of a micro wearable energy harvesting device based on FPC technology and electromagnetic coupling according to the present invention;

[0017] Figure 4 This is a schematic structural diagram of a single planar FPC coil of a micro wearable energy harvesting device based on FPC technology and electromagnetic coupling according to the present invention;

[0018] 1: Housing; 2: Planar FPC coil assembly; 3: Rotating shaft; 4: Rotating wheel; 5: Energy harvesting circuit; 6: Square permanent magnet; 7: Counterweight mass block; 8: Bearing; 9: Lightweight bracket; 10: First coil; 11: Second coil; 12: Third coil; 13: Fourth coil; 14: Fifth coil; 15: Coil; 16: FPC substrate. DETAILED DESCRIPTION

[0019] A micro wearable energy harvesting device based on FPC technology and electromagnetic coupling comprises a housing (1), a planar FPC coil group (2), a rotating shaft (3), a rotating wheel (4), and an energy harvesting circuit (5), characterized in that the planar FPC coil group (2) is fixed to the middle of the vertical direction inside the housing (1) perpendicular to the rotating shaft (3), the planar FPC coil group (2) comprises a first coil (10), a second coil (11), a third coil (12), a fourth coil (13), a fifth coil (14), and an FPC substrate (16) covering the upper and lower sides of the coils, and the rotating shaft (3) is fixed to the middle of the vertical direction inside the housing (1) perpendicular to the rotating shaft (3), and the planar FPC coil group (2) comprises a first coil (10), a second coil (11), a third coil (12), a fourth coil (13), a fifth coil (14), and an FPC substrate (16) covering the upper and lower sides of the coils. The bearing (8) is fixed vertically to the inner wall of the housing (1) and fixed above the planar FPC coil group (2). The rotating wheel (4) is installed on the outer ring of the bearing (8) and can rotate around the bearing (8). The rotating wheel (4) includes a lightweight bracket (9), 5 square permanent magnets (6) and a counterweight mass block (7). The low-frequency vibration of the outside world drives the counterweight mass block (7) to swing. The energy collection circuit (5) is fixed to the bottom of the housing (1) and is connected to the planar FPC coil group (2) through a thin wire. It can convert weak alternating current into direct current. The device can realize the collection of vibration energy in the environment and the human body.

[0020] Working principle: The planar FPC coil group (2) is composed of a first coil (10), a second coil (11), a third coil (12), a fourth coil (13), and a fifth coil (14) stacked in a high density. The rotating wheel (4) is composed of five square permanent magnets (6) with alternating magnetization patterns and a counterweight mass block (7). The counterweight mass block (7) rotates 360 degrees with external low-frequency motion, driving the rotating wheel (4) to rotate 360 ​​degrees around the bearing (8). During the swinging process of the rotating wheel (4), the square permanent magnet (6) cuts the planar FPC coil group (2), generating an induced current according to the Faraday electromagnetic induction effect, thereby realizing electromagnetic vibration energy harvesting.

[0021] Preferably, the rotating wheel (4) is a lightweight bracket (9) made of a lightweight material, and a counterweight mass block (7) is provided at the edge of the rotating wheel (4) to increase the moment of inertia. The counterweight mass block (7) can be an iron block or a copper block.

[0022] Preferably, the square permanent magnet (6) may be a samarium cobalt permanent magnet or a neodymium iron boron permanent magnet.

[0023] It should be noted that the above-mentioned technical features are further combined with each other to form various embodiments not listed above, which are all deemed to be within the scope of the present invention; and, for ordinary technicians in this field, they can be improved or transformed according to the above description, and all these improvements and transformations should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A micro wearable energy harvesting device based on FPC technology and electromagnetic coupling, comprising a housing (1), a planar FPC coil group (2), a rotating shaft (3), a rotating wheel (4), and an energy harvesting circuit (5), characterized in that: The planar FPC coil group (2) is fixed at the middle of the vertical direction inside the housing (1) perpendicular to the rotating shaft (3). The planar FPC coil group (2) includes a first coil (10), a second coil (11), a third coil (12), a fourth coil (13), a fifth coil (14), and an FPC substrate (16) covering the upper and lower sides of the coil (15). The coil (15) is miniaturized and has a higher density by adopting the FPC process. The rotating shaft (3) is fixed perpendicularly to the inner wall of the housing (1) through a bearing (8). The rotating wheel (4) is installed on the outer ring of the bearing (8) and can rotate around the bearing (8). The rotating wheel (4) includes a light material. The invention comprises a lightweight bracket (9), five square permanent magnets (6) and a counterweight mass block (7). The counterweight mass block (7) is arranged at the edge of the rotating wheel (4). The counterweight mass block (7) is an iron block or a copper block. The five square permanent magnets (6) are embedded in the rotating wheel (4) at equal intervals. The low-frequency vibration of the outside world drives the counterweight mass block (7) to swing. The energy collection circuit (5) is fixed on the inner side of the bottom of the housing (1) and below the planar FPC coil group (2). The base material thereof is a glass fiber PCB or a flexible FPC. The circuit is connected to the planar FPC coil group (2) through a thin wire to convert a weak alternating current into a direct current. The device can realize the collection of vibration energy in the environment and the human body.

2. According to claim 1, a micro wearable energy harvesting device based on FPC technology and electromagnetic coupling is characterized in that: The rotating wheel (4) swings within a range of 360 degrees along with the external low-frequency motion.

3. According to claim 1, a micro wearable energy harvesting device based on FPC technology and electromagnetic coupling is characterized in that: The planar FPC coil group (2) is fixed to the inner side of the bottom of the housing (1), below the rotating wheel (4), and parallel to the lightweight bracket (9). When the rotating wheel (4) is swung, the square permanent magnet (6) cuts the planar FPC coil group (2), thereby realizing electromagnetic vibration energy collection.

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