A wireless charging receiving device and an electronic product

Abstract

A wireless charging receiver includes a first soft magnet, a receiving coil, and a flexible circuit board. The first soft magnet has a first through hole. The receiving coil includes a first connecting end and a second connecting end. The flexible circuit board includes inner and outer conductive lines. The inner conductive line is located above the first soft magnet, passes through the first through hole, and connects to the first connecting end. The outer conductive line is located below the first soft magnet and connects to the second connecting end. An electronic product includes a battery and the aforementioned wireless charging receiver. This invention reduces the eddy currents formed by the magnetic field of the receiving coil on the inner conductive lines, reduces the heat generated by the wireless charging receiver, and lowers the temperature rise of the electronic product during charging. Simultaneously, it improves the efficiency of wireless charging and accelerates the charging speed of the electronic product.

Description

Technical Field

[0001] This invention relates to the field of wireless charging technology, and more particularly to a wireless charging receiver and electronic product. Prior Technology

[0002] The main components of a wireless charging receiver are a receiving coil, a soft magnet, and a circuit board. The receiver is built into the electronic device being charged, such as a mobile phone, tablet, or smartwatch. When the device is brought close to the charging dock, the transmitting coil in the dock, powered by alternating current of a certain frequency, induces a current in the receiving coil of the device through electromagnetic induction. This transmits energy from the transmitting end to the receiving end, thus charging the device. Because current is generated at the receiving end, the device heats up, potentially causing overheating, malfunction, or even explosion.

[0003] In order to minimize the temperature rise of electronic products being charged, the main charging method for mobile phones, tablets and other electronic products in the current technology is to limit the charging current of the circuit. Limiting the current will result in low charging efficiency of electronic products. As a result, users will feel that although the product is no longer hot, the charging is obviously slower, which will reduce the user's satisfaction.

[0004] Given the prevalence of the aforementioned problems in electronic products on the market, there is an urgent need for a wireless charging receiver and electronic product to solve these technical issues. Summary of the Invention

[0005] Based on the above, the purpose of this invention is to provide a wireless charging receiver and electronic product that can reduce the temperature rise of the electronic product during the wireless charging process and improve the charging efficiency of the electronic product.

[0006] To achieve this objective, the present invention adopts the following technical solution:

[0007] A wireless charging receiver includes: a first soft magnet having a first through hole extending through its upper and lower surfaces; a receiving coil disposed below the first soft magnet, the receiving coil including a first connecting end wound on the inner side and a second connecting end wound on the outer side; and a flexible circuit board including an inner conductor line and an outer conductor line, the inner conductor line being located above the first soft magnet and connected to the first connecting end after passing through the first through hole, and the outer conductor line being located below the first soft magnet and connected to the second connecting end.

[0008] In some possible implementations, a portion of the outer conductor line is positioned directly below the first soft magnet, while another portion of the outer conductor line is laterally exposed above the first soft magnet.

[0009] In some possible implementations, a portion of the inner conductor is positioned directly above the first soft magnet, and another portion of the inner conductor extends laterally out of the first soft magnet; the end of the inner conductor extending laterally out of the first soft magnet is connected to the end of the outer conductor extending laterally out of the first soft magnet.

[0010] In some possible implementations, the coverage area of ​​the first soft magnet is larger than the coverage area of ​​the receiving coil.

[0011] In some possible implementations, the wireless charging receiver further includes a second soft magnet disposed above the first soft magnet and covering the connection point between the inner conductor and the first connection end.

[0012] In some possible implementations, the coverage area of ​​the second soft magnet is smaller than the coverage area of ​​the receiving coil.

[0013] In some possible implementations, the internal wiring of the flexible circuit board includes multiple sub-wires arranged in parallel.

[0014] In some possible implementations, the internal wiring of the flexible circuit board is stranded wire or self-adhesive enameled wire.

[0015] In some possible implementations, the flexible circuit board is a single-sided or double-sided FPC circuit board.

[0016] In some possible implementations, the wireless charging receiver further includes a connector disposed on the side of the receiving coil opposite to the first soft magnet, for securing it to an electronic product. The connector is made of colloid or Mylar.

[0017] In some possible implementations, the first connection end of the receiving coil is connected to the inner conductor line of the flexible circuit board by soldering, and the second connection end of the receiving coil is connected to the outer conductor line of the flexible circuit board by soldering.

[0018] In some possible implementations, the receiving coil is fixed to the first soft magnet, and the first soft magnet is fixed to the flexible circuit board by adhesive bonding.

[0019] In some possible implementations, the second soft magnet is fixed to the first soft magnet by adhesive bonding.

[0020] In some possible implementations, the wireless charging receiver further includes a heat dissipation component for dissipating heat from the receiving coil; and / or, the wireless charging receiver further includes a rigid protective film component disposed on the outside of the first soft magnet; and / or, the wireless charging receiver further includes a reinforcing component fixed to the first soft magnet or the receiving coil.

[0021] An electronic product, including a battery and a wireless charging receiver as described in any of the above embodiments, wherein the wireless charging receiver is used to charge the battery.

[0022] The beneficial effects of this invention:

[0023] The wireless charging receiver provided by this invention places the inner and outer wires of a flexible circuit board on the upper and lower sides of a first soft magnet, respectively. The inner wires are located above the first soft magnet, and the outer wires are located below it. The inner wires pass through a first through-hole and connect to a first connection end coiled inside the receiving coil below the first soft magnet. The outer wires connect to a second connection end coiled outside the receiving coil. Since eddy currents are easily generated in the inner wires of a flexible circuit board, this invention uses the first soft magnet to separate the inner wires from the receiving coil, thereby reducing the eddy currents formed by the magnetic field of the receiving coil on the inner wires. This effectively reduces the heat generated by the wireless charging receiver, lowers the temperature rise of electronic products during charging, and improves the user experience and charging safety. Furthermore, this invention allows the wireless charging receiver to continuously operate at high current and full load, effectively improving wireless charging efficiency and accelerating the charging speed of electronic products. Simple Explanation of the Diagram

[0024] Figure 1 is a schematic diagram of the front structure of a wireless charging receiver in the prior art; Figure 2 is a schematic diagram of the rear structure of a wireless charging receiver in the prior art; Figure 3 is a simulation diagram of the temperature rise of a wireless charging receiver during charging in the prior art; Figure 4 is a front structural schematic diagram of the wireless charging receiver provided in an embodiment of the present invention; Figure 5 is a front structural schematic diagram of the wireless charging receiver (second soft magnet not shown) provided in an embodiment of the present invention; Figure 6 is a schematic diagram of the rear structure of the wireless charging receiver (connector not shown) provided in an embodiment of the present invention; Figure 7 is an exploded view of the wireless charging receiver provided in an embodiment of the present invention; Figure 8 is a schematic diagram of the receiving coil and flexible circuit board provided in an embodiment of the present invention; Figure 9 is a schematic diagram of the internal conductive lines of the flexible circuit board provided in an embodiment of the present invention; Figure 10 is a simulation diagram of the temperature rise during charging of the wireless charging receiver provided in an embodiment of the present invention. Implementation

[0025] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0026] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0027] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0028] In the description of this invention, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0029] As shown in Figures 1-3, existing wireless charging receivers include a soft magnet 1', a receiving coil 2', and a flexible circuit board 3'. The lines of the receiving coil 2' and the flexible circuit board 3' are all located on the same side of the soft magnet 1'. This structure easily generates eddy currents in the flexible circuit board 3', resulting in high heat generation in the wireless charging receiver and excessive temperature rise in electronic products. While limiting the charging current can reduce overheating, it can also lead to lower charging efficiency in electronic products.

[0030] To address the aforementioned issues, this embodiment provides a wireless charging receiver device, which serves as the receiving end of a wireless charging system and can be applied to electronic products such as mobile phones, tablets, laptops, smartwatches, and smart glasses. This solves the problems of excessive temperature rise and slow charging speed of electronic products during wireless charging in the prior art.

[0031] As shown in Figures 4 to 10, the wireless charging receiver provided in this embodiment includes a first soft magnet 1, a receiving coil 2, and a flexible circuit board 3. The first soft magnet 1 has an electromagnetic shielding function, and a first through hole 11 is formed on the first soft magnet 1, penetrating its upper and lower surfaces. Preferably, the first through hole 11 is located in the middle region of the first soft magnet 1. The receiving coil 2 is located below the first soft magnet 1. The receiving coil 2 is specifically a wound coil containing metal material, wound in a ring shape, including a first connecting end 21 wound on the inner side and a second connecting end 22 wound on the outer side. The first connecting end 21 is located below the first through hole 11, and the second connecting end 22 is located near the edge of the first soft magnet 1. The flexible circuit board 3 includes an inner conductor line 31 and an outer conductor line 32. The inner conductor line 31 is located above the first soft magnet 1, passes through the first through hole 11, and connects to the first connecting end 21. The outer conductor line 32 is located below the first soft magnet 1 and connects to the second connecting end 22, thus forming a closed circuit for charging electronic products. In this embodiment, the flexible circuit board 3 is a single-sided or double-sided FPC circuit board.

[0032] The wireless charging device provided in this embodiment places the inner wire line 31 and the outer wire line 32 of the flexible circuit board 3 on the upper and lower sides of the first soft magnet 1, respectively. The inner wire line 31 is located above the first soft magnet 1, and the outer wire line 32 is located below the first soft magnet 1. The inner wire line 31 passes through the first through hole 11 and is connected to the first connecting end 21, which is coiled inside the receiving coil 2 below the first soft magnet 1. The outer wire line 32 is connected to the second connecting end 22, which is coiled outside the receiving coil 2. Since eddy currents are easily generated in the inner wire line 31 in the flexible circuit board 3, this embodiment uses the first soft magnet 1 to separate the inner wire line 31 from the receiving coil 2, thereby reducing the eddy currents formed by the magnetic field of the receiving coil 2 on the inner wire line 31. This effectively reduces the heat generation of the wireless charging receiving device, reduces the temperature rise of electronic products, and improves the user experience and charging safety of electronic products. Moreover, this embodiment can continuously keep the wireless charging receiving device in a stable high-current, full-load working state, effectively improving the efficiency of wireless charging and accelerating the charging speed of electronic products.

[0033] Optionally, a portion of the outer conductor line 32 is disposed directly below the first soft magnet 1 for connection to the second connection terminal 22 of the receiving coil 2, so as to prevent the second connection terminal 22 from protruding outside the first soft magnet 1; another portion of the outer conductor line 32 is laterally exposed outside the first soft magnet 1 for connection to the inner conductor line 31. Optionally, the portion of the outer conductor line 32 located directly below the first soft magnet 1 is in contact with the lower surface of the first soft magnet 1 to ensure the connection stability between the outer conductor line 32 and the first soft magnet 1.

[0034] Furthermore, a portion of the inner conductor line 31 is positioned directly above the first soft magnet 1 for connection to the first connection terminal 21 of the receiving coil 2; another portion of the inner conductor line 31 is laterally exposed above the first soft magnet 1, and the end of the inner conductor line 31 laterally exposed above the first soft magnet 1 is interconnected with the end of the outer conductor line 32 laterally exposed above the first soft magnet 1. Optionally, the portion of the inner conductor line 31 located directly above the first soft magnet 1 is fitted to the upper surface of the first soft magnet 1 to ensure the connection stability between the inner conductor line 31 and the first soft magnet 1.

[0035] Optionally, the wireless charging receiver in this embodiment further includes a second soft magnet 4, which is disposed above the first soft magnet 1 and covers the area above the connection point between the inner conductor line 31 and the first connection terminal 21. By disposing of the second soft magnet 4 above the inner conductor line 31, this embodiment can shield the leakage magnetic field of the receiving coil 2 at the first through hole 11, further improving the electromagnetic shielding effect and enhancing the performance of the wireless charging receiver.

[0036] In this embodiment, the coverage area of ​​the first soft magnet 1 is larger than that of the receiving coil 2, allowing the receiving coil 2 to be completely mounted on the first soft magnet 1, effectively providing electromagnetic shielding for the receiving coil 2. Furthermore, the coverage area of ​​the second soft magnet 4 is smaller than that of the receiving coil 2 but larger than the area of ​​the first through hole 11. In this embodiment, the size of the second soft magnet 4 only needs to be sufficient to cover the connection between the internal conductor 31 and the first connecting end 21, without needing to be excessively large to avoid material waste. Optionally, in this embodiment, the receiving coil 2 is annular, the first soft magnet 1 is a rectangular (i.e., one end of the rectangle is rounded) soft magnetic sheet, and the second soft magnet 4 is a circular soft magnetic sheet. Of course, in other embodiments, the shapes of the receiving coil 2, the first soft magnet 1, and the second soft magnet 4 can also be other shapes, and are not limited to this embodiment.

[0037] In this embodiment, the materials of the first soft magnet 1 and the second soft magnet 4 can be ferrite materials, ferrite amorphous materials, ferrite amorphous nanomaterials, or ferrite composite materials, etc. Preferably, the first soft magnet 1 and the second soft magnet 4 in this embodiment are both made of nanocrystalline materials or ferrite. Nanocrystalline materials have high saturation magnetic induction, high permeability, and low magnetic loss, while also being flexible and ultra-thin. Ferrite is prepared and sintered from ferric oxide and one or more other metal oxides (e.g., nickel oxide, zinc oxide, manganese oxide, magnesium oxide, barium oxide, strontium oxide, etc.), which can be mass-produced, has stable performance, and high machinability.

[0038] Optionally, in this embodiment, the inner conductor line 31 of the flexible circuit board 3 includes multiple strands of sub-lines 311 arranged in parallel. Since the area with the strongest magnetic field (i.e., the area most prone to eddy current formation) in the flexible circuit board 3 is the inner conductor line 31, this embodiment subdivides the inner conductor line 31 into multiple strands of sub-lines 311, which can further reduce eddy currents in the circuit. Specifically, the inner conductor line 31 in this embodiment can be stranded wire or self-adhesive enameled wire. It should be noted that the above-mentioned stranded wire refers to a conductor in which a single conductor is formed by stranding or braiding multiple independently insulated conductors; the above-mentioned self-adhesive enameled wire refers to a conductor in which the coils are bonded together under appropriate solvent or heating conditions. Exemplarily, the inner conductor line 31 in this embodiment is a flat conductor with a certain width. The flat conductor is divided into multiple parallel and spaced sub-lines 311 in the area directly above the first soft magnet 1. Its structure is simple, easy to process, and has stable performance.

[0039] Optionally, the wireless charging receiver in this embodiment further includes a connector 5, which is disposed on the side of the receiving coil 2 away from the first soft magnet 1, for fixing to the electronic product. This embodiment, by providing a connector 5 on one side of the receiving coil 2, allows the wireless charging receiver to be better assembled with mobile phones, tablets, and other devices. Specifically, the connector 5 is made of adhesive or Mylar. Further, the connector 5 is sheet-shaped, with the same shape as the first soft magnet 1, to achieve a better connection effect. In this embodiment, when the connector 5 is made of adhesive, the adhesive can be hot melt adhesive or pressure-sensitive adhesive, and can be double-sided or single-sided adhesive; when the connector 5 is made of Mylar, a second through hole 12 penetrating the upper and lower surfaces of the first soft magnet 1 can be opened, and a connection hole is also provided on the Mylar, thereby securing the wireless charging receiver to the electronic product with a fastening screw.

[0040] In this embodiment, the first connection end 21 of the receiving coil 2 is connected to the inner conductor line 31 of the flexible circuit board 3 by welding, and the second connection end 22 of the receiving coil 2 is connected to the outer conductor line 32 of the flexible circuit board 3 by welding. After the receiving coil 2 and the flexible circuit board 3 form a circuit, they can be connected to electronic products such as mobile phones or tablets to charge the electronic products. Optionally, the receiving coil 2 and the first soft magnet 1, the first soft magnet 1 and the flexible circuit board 3, and the second soft magnet 4 and the first soft magnet 1 are all fixed by adhesive bonding. For example, they can be bonded with single-sided adhesive or double-sided adhesive. The above connection method is convenient to operate and flexible to assemble.

[0041] Optionally, the wireless charging receiver in this embodiment further includes a heat dissipation component for dissipating heat from the receiving coil 2, thereby further reducing the temperature rise of the electronic product. Specifically, the heat dissipation component can be a graphite heat sink or a silicone heat sink, and the heat dissipation component is fixed to the first soft magnet 1 or the connector 5 by adhesive bonding to improve the heat dissipation capacity of the electronic product.

[0042] Optionally, the wireless charging receiver in this embodiment further includes a rigid protective film component. The rigid protective film component is disposed on the outside of the first soft magnet 1 to increase the rigidity of the wireless charging receiver and improve its structural strength. Further, the wireless charging receiver also includes a reinforcing component, which is fixed to the first soft magnet 1 or the receiving coil 2. Specifically, the reinforcing component can be a reinforcing plate, and the material of the reinforcing plate can be plastic or metal. By setting the reinforcing component, the wireless charging receiver can have higher strength, is less prone to deformation, and better match electronic products.

[0043] Figure 3 is a simulation diagram of the temperature rise during charging of a wireless charging receiver in the prior art, and Figure 10 is a simulation diagram of the temperature rise during charging of the wireless charging receiver provided in this embodiment. A comparison of Figures 3 and 10 shows that, compared to traditional wireless charging receivers, the wireless charging receiver provided in this embodiment, due to the inner conductor line 31 being on the upper side of the first soft magnet 1, reduces the eddy currents formed by the magnetic field of the receiving coil 2 on the inner conductor line 31. Therefore, it generates less heat, has a more uniform temperature, and does not exhibit concentrated hot spots, resulting in a significant temperature improvement effect.

[0044] Furthermore, as shown in the table below, a comparison of temperature rise data of the prior art and the wireless charging receiver provided in this improved embodiment is presented. state Inductance (L) 100kHz = Resistance (R) Q-Factor phase Current (A) B (Tesla) Max: Efficiency_% Max: Temperature rise Before improvement 8.2uH 281mohm 18.38 0 2 0.0395 81% 58ﾟ After improvement 8.2uH 281mohm 18.38 0 2 0.0056 83% 51ﾟ

[0045] This comparative experiment was conducted at a frequency of 100kHz, with the same inductance L, resistance R, and Q values. Inductance L represents the receiving coil's ability to store magnetic field energy; its value indicates the coil's size or the number of coils. Resistance R represents the internal resistance of the coil's conductors. Q is the quality factor, representing the coil's performance at its operating frequency; specifically, Q is the ratio of the coil's self-inductance L to its resistance R, i.e., Q = ωL / R, where ω is the angular frequency (2π multiplied by the frequency). The table clearly shows that, under the same conditions, the improved solution in this embodiment effectively reduces the magnetic flux density B (Tesla) in the internal conductors during wireless charging, lowers temperature rise, improves charging efficiency, and simultaneously ensures device safety and lifespan compared to existing solutions.

[0046] This embodiment also provides an electronic product, including a housing, a battery, and a wireless charging receiver as described in any of the above solutions. Both the battery and the wireless charging receiver are installed inside the housing, and the wireless charging receiver is used to charge the battery. When the electronic product provided in this embodiment is near a charging base, its charging process is as follows: An alternating current is passed through the transmitting coil inside the charging base to generate a continuously changing magnetic field. The receiving coil 2 senses the changing magnetic field generated by the transmitting coil and generates an induced current. After further processing, the induced current charges the battery. This embodiment reduces the eddy currents formed by the magnetic field of the receiving coil 2 on the inner conductor line 31, reduces the heat generated by the wireless charging receiver, and lowers the temperature rise of the electronic product; at the same time, it improves the efficiency of wireless charging and accelerates the charging speed of the electronic product.

[0047] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of this invention.

[0048] 1': Soft magnet 2': Receiving coil 3': Flexible circuit board 1: First soft magnet 11: First through hole 12: Second through hole 2: Receiving coil 21: First connection end 22: Second connection end 3: Flexible circuit board 31: Internal conductor circuit 311: Sub-line 32: External conductor circuit 4: Second soft magnet 5: Connectors

Claims

1. A wireless charging receiver, comprising: A first soft magnet (1) has a first through hole (11) extending through its upper and lower surfaces; a receiving coil (2) is disposed below the first soft magnet (1), the receiving coil (2) includes a first connecting end (21) coiled on the inner side and a second connecting end (22) coiled on the outer side; a flexible circuit board (3) includes an inner conductor line (31) and an outer conductor line (32), the inner conductor line (31) is located above the first soft magnet (1) and connected to the first connecting end (21) after passing through the first through hole (11), the outer conductor line (32) is located below the first soft magnet (1) and connected to the second connecting end (22).

2. The wireless charging receiver according to claim 1, wherein, A portion of the external conductor line (32) is disposed directly below the first soft magnet (1), and another portion of the external conductor line (32) is exposed laterally to the first soft magnet (1).

3. The wireless charging receiver according to claim 2, wherein, A portion of the inner conductor line (31) is positioned directly above the first soft magnet (1), and another portion of the inner conductor line (31) is laterally exposed to the first soft magnet (1); the end of the inner conductor line (31) laterally exposed to the first soft magnet (1) is connected to the end of the outer conductor line (32) laterally exposed to the first soft magnet (1).

4. The wireless charging receiver according to claim 1, wherein, The coverage area of ​​the first soft magnet (1) is greater than the coverage area of ​​the receiving coil (2).

5. The wireless charging receiver according to claim 1, wherein, The internal conductor lines (31) of the flexible circuit board (3) include multiple sub-lines (311) arranged in parallel.

6. The wireless charging receiver according to claim 5, wherein, The internal conductor lines (31) of the flexible circuit board (3) are stranded wires or self-adhesive enameled wires.

7. The wireless charging receiver according to claim 1, wherein, The first connection end (21) of the receiving coil (2) is connected to the inner conductor line (31) of the flexible circuit board (3) by welding, and the second connection end (22) of the receiving coil (2) is connected to the outer conductor line (32) of the flexible circuit board (3) by welding.

8. The wireless charging receiver according to claim 1, wherein, The receiving coil (2) and the first soft magnet (1) are fixed together by adhesive bonding. The first soft magnet (1) and the flexible circuit board (3) are also fixed together by adhesive bonding.

9. The wireless charging receiver according to claim 1, wherein, The wireless charging receiver also includes a rigid protective film component, which is disposed on the outside of the first soft magnet (1).

10. An electronic product comprising a battery and a wireless charging receiver according to any one of claims 1-9, the wireless charging receiver being used to charge the battery.

Images