A wireless charger and auxiliary charging device thereof

Abstract

The present invention discloses a wireless charger and an auxiliary charging device thereof. Since the outer diameter of a relay coil is larger than the outer diameter of a receiving coil of the wireless charger, in this case, the magnetic field range that the relay coil can receive is also larger than the magnetic field range that the receiving coil can receive. Therefore, the relay coil receives a larger magnetic flux in a larger magnetic field, and the current induced by the relay coil is larger than that of the receiving coil, so that the receiving coil can induce a larger current than before, thereby improving the transmission efficiency and saving energy. In addition, the annular magnetic isolation device can isolate the magnetic field outside the receiving coil and will not affect the magnetic field inside the receiving coil. Under the premise of not affecting the electromagnetic induction work, it can prevent the metal devices around the receiving coil from generating eddy currents and heating, thereby avoiding the reduction of charging speed due to triggering the temperature protection mechanism of the electronic product, thereby improving the charging speed.

Description

Technical Field

[0001] The present invention relates to the field of electromagnetic induction, and in particular to an auxiliary charging device. The present invention also relates to a wireless charger. Background Art

[0002] Wireless charging technology is currently developing rapidly. Wireless charging usually uses electromagnetic induction technology, that is, alternating current is passed through the transmitting coil to generate a changing magnetic field, and the receiving coil located in the changing magnetic field can induce alternating current. However, the magnetic field generated by the transmitting coil has a large range, and the receiving coil can only use the magnetic field passing through its own internal magnetic field to induce current, and cannot use the magnetic field outside its own coil, resulting in low transmission efficiency and waste of energy. In addition, the magnetic field outside the receiving coil will cause the metal devices located outside the receiving coil in the electronic product to generate eddy currents and heat up, which can easily trigger the temperature protection mechanism of the electronic product and reduce the charging speed. There is no mature product in the existing technology that can solve the above two problems at the same time.

[0003] Therefore, how to provide a solution to the above technical problems is a problem that those skilled in the art need to solve at present. Summary of the invention

[0004] An object of the present invention is to provide an auxiliary charging device, which improves transmission efficiency, saves energy, avoids a decrease in charging speed due to triggering a temperature protection mechanism of an electronic product, and improves the charging speed; another object of the present invention is to provide a wireless charger including the above-mentioned auxiliary charging device, which improves transmission efficiency, saves energy, avoids a decrease in charging speed due to triggering a temperature protection mechanism of an electronic product, and improves the charging speed.

[0005] In order to solve the above technical problems, the present invention provides an auxiliary charging device, which is applied to a wireless charger, comprising:

[0006] A relay coil coaxially arranged between a transmitting coil and a receiving coil of the wireless charger, for inducing alternating current and generating a changing magnetic field inside itself when located in the magnetic field generated by the transmitting coil, so that the receiving coil generates an induced current;

[0007] An annular magnetic isolation device coaxially arranged on a side of the relay coil that is closer to the receiving coil, for isolating the magnetic field located outside the receiving coil;

[0008] A fixing device, used for fixing the relay coil and the annular magnetic isolation device;

[0009] Among them, the outer diameter of the relay coil is larger than the outer diameter of the receiving coil, and the inner diameter of the annular magnetic isolation device is not smaller than the outer diameter of the receiving coil.

[0010] Preferably, the relay coil includes a first sub-coil and a second sub-coil;

[0011] The first end of the first sub-coil is connected to the first end of the second sub-coil, the second end of the first sub-coil is connected to the first end of the capacitor, and the second end of the second sub-coil is connected to the second end of the capacitor;

[0012] The first sub-coil and the second sub-coil are co-centered, a preset distance between an outer edge of the first sub-coil and an inner edge of the second sub-coil is greater than zero, and an outer diameter of the first sub-coil is not less than an outer diameter of the receiving coil.

[0013] Preferably, the coil comprises a plurality of strands of Litz wire.

[0014] Preferably, the auxiliary charging device further comprises:

[0015] The first end is connected to the first end of the first sub-coil, and the second end is connected to the first end of the second sub-coil via a capacitor, which is used to form an LC series resonant circuit with the coil to reduce the circuit impedance.

[0016] Preferably, the annular magnetic isolation device includes a plurality of magnetic shielding stickers arranged in an annular shape.

[0017] Preferably, the magnetic shielding sticker is a ferrite soft magnetic sheet.

[0018] Preferably, the inner diameter of the annular magnetic isolation device is greater than a preset value of the outer diameter of the receiving coil.

[0019] Preferably, the fixing device is a packaging shell made of insulating material.

[0020] Preferably, the magnetic shielding sticker is in the shape of a fan ring.

[0021] In order to solve the above technical problems, the present invention further provides a wireless charger, comprising the auxiliary charging device as described in any one of the above items.

[0022] The present invention provides an auxiliary charging device. Since the outer diameter of the relay coil is larger than the outer diameter of the wireless charger receiving coil, in this case, the magnetic field range that the relay coil can receive is also larger than the magnetic field range that the receiving coil can receive. Therefore, the relay coil is equivalent to being able to receive a larger magnetic flux in a larger magnetic field range, and can generate a larger current than the receiving coil. Then, the magnetic field generated by the relay coil can enable the receiving coil to induce a larger current than before, thereby improving the transmission efficiency and saving energy. In addition, since the annular magnetic isolation device is arranged on the side closer to the relay coil and the receiving coil, and the inner diameter of the annular magnetic isolation device is not less than the outer diameter of the receiving coil, in this case, the annular magnetic isolation device can isolate the magnetic field located outside the receiving coil, and will not affect the magnetic field located inside the receiving coil. Under the premise of not affecting the electromagnetic induction work, it can prevent the metal devices around the receiving coil from generating eddy currents and heating, thereby avoiding the reduction in charging speed due to triggering the temperature protection mechanism of the electronic product, thereby improving the charging speed.

[0023] The present invention also provides a wireless charger having the same beneficial effects as the above auxiliary charging device. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the prior art and the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 A schematic diagram of the structure of an auxiliary charging device provided by the present invention;

[0026] Figure 2 A schematic diagram of the structure of a relay coil provided by the present invention;

[0027] Figure 3 A schematic structural diagram of an annular magnetic isolation device provided by the present invention. DETAILED DESCRIPTION

[0028] The core of the present invention is to provide an auxiliary charging device, which improves transmission efficiency, saves energy, and avoids the decrease in charging speed due to triggering the temperature protection mechanism of electronic products, thereby improving the charging speed; another core of the present invention is to provide a wireless charger including the above-mentioned auxiliary charging device, which improves transmission efficiency, saves energy, and avoids the decrease in charging speed due to triggering the temperature protection mechanism of electronic products, thereby improving the charging speed.

[0029] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Please refer to Figure 1 , Figure 1 A schematic structural diagram of an auxiliary charging device provided by the present invention includes:

[0031] The relay coil 1 is coaxially arranged between the transmitting coil and the receiving coil of the wireless charger, and is used to induce alternating current and generate a changing magnetic field inside itself when it is located in the magnetic field generated by the transmitting coil, so that the receiving coil generates an induced current;

[0032] The annular magnetic isolation device 2 is coaxially arranged on the side of the relay coil 1 that is closer to the receiving coil, and is used to isolate the magnetic field located outside the receiving coil;

[0033] A fixing device 3, used for fixing the relay coil 1 and the annular magnetic isolation device 2;

[0034] The outer diameter of the relay coil 1 is larger than the outer diameter of the receiving coil, and the inner diameter of the annular magnetic isolation device 2 is not smaller than the outer diameter of the receiving coil.

[0035] Specifically, the relay coil 1 may be coaxially arranged with the transmitting coil and the receiving coil. In this case, the transmission efficiency between the transmitting coil and the relay coil 1 and between the relay coil 1 and the receiving coil may be maximized.

[0036] Specifically, the relay coil 1 mainly plays a role of magnetic gathering. Assuming that in the same position, the current that the receiving coil can originally generate is A, after adding the relay coil 1, since the relay coil 1 has a larger area, it can perform magnetic induction and save power according to a larger magnetic field, and can generate a larger current than the original receiving coil. The relay coil 1 then enables the receiving coil to induce a larger current. In order to increase the energy transmission efficiency between the relay coil 1 and the receiving coil, the electronic device corresponding to the receiving coil can be placed close to the relay coil 1 when in use.

[0037] Among them, as long as the outer diameter of the relay coil 1 is larger than the outer diameter of the receiving coil, the magnetic field concentration effect can be generated to improve the transmission efficiency. The specific number of turns and shape in the relay coil 1 can be set independently. For example, the most suitable number of turns and shape of the relay coil 1 can be set by simulating the correspondence between the number of turns and shape and the coupling coefficient. The embodiments of the present invention are not limited here.

[0038] It should also be noted that the magnetic field collecting device in the embodiment of the present invention can be applied to both close-fitting and air-gapped wireless chargers. The common point is that the magnetic field collecting device must be placed in close proximity to the electronic product corresponding to the receiving coil so as to maximize the coupling coefficient between the relay coil 1 and the receiving coil. For example, when used in an air-gapped wireless charger, the plane of the relay coil 1 and the transmitting coil are loosely coupled, and the distance is the air-gapped distance of wireless charging. At this distance, the coupling coefficient between the transmitting coil and the relay coil 1 of the magnetic field collecting device is simulated by electromagnetic simulation software to maximize the coupling coefficient, thereby determining the outer diameter of the relay coil 1. The plane of the relay coil 1 of the magnetic field collecting device and the receiving coil can be tightly coupled, and the two are in close proximity, so as to maximize the coupling coefficient between the two.

[0039] Among them, after the magnetic field effect is generated, if the distance between the receiving coil and the transmitting coil of the wireless charger is not changed and the receiving power is guaranteed to be the same, then the current in the transmitting coil can be reduced or the size of the transmitting coil can be reduced to save energy. Of course, if the parameters of the transmitting coil are not changed under the condition of ensuring the same receiving power, the distance between the transmitting coil and the receiving coil can be increased, which increases the convenience and flexibility of use.

[0040] Specifically, the fixing device 3 can fix the relay coil 1 and the annular magnetic isolation device 2 together, which reduces the cost caused by separate fixing and is convenient for users to store and manage and prevent damage.

[0041] Specifically, the annular magnetic isolation device 2 has the effect of isolating the magnetic field, and it can be made of various types of magnetic isolation materials, which is not limited in the embodiment of the present invention.

[0042] Specifically, since the annular magnetic isolation device 2 is coaxially arranged between the transmitting coil and the receiving coil, and the inner diameter of the annular magnetic isolation device 2 is not smaller than the outer diameter of the receiving coil, the magnetic field generated by the transmitting coil in the outer circle of the receiving coil can be shielded by the annular magnetic isolation device 2, and at the same time will not affect the magnetic field within the inner diameter of the annular magnetic isolation device 2. The magnetic field within the inner diameter of the annular magnetic isolation device 2 can cause the receiving coil to induce alternating current.

[0043] Among them, the outer diameter size of the annular magnetic isolation device 2 can be independently set according to actual needs. Of course, the size of the outer diameter has a corresponding relationship with the cost and the shielding effect. The optimal outer diameter size can be found by seeking the corresponding relationship. The embodiment of the present invention is not limited here.

[0044] Specifically, since the magnetic shielding material is usually in a relatively soft state, in order to prevent the annular magnetic isolation device 2 from being damaged due to arbitrary deformation, the fixing device 3 can fix the annular magnetic isolation device 2 so that the user can move it conveniently, thereby protecting the annular magnetic isolation device 2 from being easily damaged.

[0045] The present invention provides an auxiliary charging device. Since the outer diameter of the relay coil is larger than the outer diameter of the wireless charger receiving coil, in this case, the magnetic field range that the relay coil can receive is also larger than the magnetic field range that the receiving coil can receive. Therefore, the relay coil is equivalent to being able to receive a larger magnetic flux in a larger magnetic field range, and can generate a larger current than the receiving coil. Then, the magnetic field generated by the relay coil can enable the receiving coil to induce a larger current than before, thereby improving the transmission efficiency and saving energy. In addition, since the annular magnetic isolation device is arranged on the side closer to the relay coil and the receiving coil, and the inner diameter of the annular magnetic isolation device is not less than the outer diameter of the receiving coil, in this case, the annular magnetic isolation device can isolate the magnetic field located outside the receiving coil, and will not affect the magnetic field located inside the receiving coil. Under the premise of not affecting the electromagnetic induction work, it can prevent the metal devices around the receiving coil from generating eddy currents and heating, thereby avoiding the reduction in charging speed due to triggering the temperature protection mechanism of the electronic product, thereby improving the charging speed.

[0046] To better illustrate the embodiments of the present invention, please refer to Figure 2 , Figure 2 A schematic diagram of the structure of a relay coil provided by the present invention, based on the above embodiment:

[0047] As a preferred embodiment, the relay coil 1 includes a first sub-coil 11 and a second sub-coil 12;

[0048] The first end of the first sub-coil 11 is connected to the first end of the second sub-coil 12, the second end of the first sub-coil 11 is connected to the first end of the capacitor, and the second end of the second sub-coil 12 is connected to the second end of the capacitor;

[0049] The first sub-coil 11 and the second sub-coil 12 are co-centered, the preset distance between the outer edge of the first sub-coil 11 and the inner edge of the second sub-coil 12 is greater than zero, and the outer diameter of the first sub-coil 11 is not less than the outer diameter of the receiving coil.

[0050] Specifically, since the preset distance between the outer edge of the first sub-coil 11 and the inner edge of the second sub-coil 12 is greater than zero, the number of coils can be effectively reduced to save costs. Since the outer diameter of the first sub-coil 11 is not less than the outer diameter of the receiving coil, the coupling coefficient between the relay coil 1 and the receiving coil is large enough to ensure transmission efficiency.

[0051] The preset distance may be independently set according to actual needs, and the embodiment of the present invention does not limit this.

[0052] In addition, a through hole with a diameter less than a certain value can be set inside the first sub-coil 11. This method is conducive to further reducing wire materials and saving costs. Through simulation, it is found that the existence of the through hole does not affect the transmission efficiency between the relay coil 1 and the receiving coil.

[0053] The winding directions of the first sub-coil 11 and the second sub-coil 12 should be the same.

[0054] Of course, in addition to the specific form of the relay coil 1 provided in the embodiment of the present invention, the relay coil 1 may also be in many other forms, which is not limited in the embodiment of the present invention.

[0055] The first sub-coil 11 and the second sub-coil 12 may be coplanar. In this case, the structure of the relay coil and even the entire additional device can be simplified, the volume can be reduced, and the cost can be saved.

[0056] Of course, the plane where the first sub-coil 11 is located and the plane where the second sub-coil 12 is located can also be different planes. For example, the plane where the second sub-coil 12 is located is closer to the transmitting coil. The transmission efficiency can be improved by setting the inductance of the first sub-coil 11 and the second sub-coil 12 and the system resonant frequency. The present invention is not limited here.

[0057] As a preferred embodiment, the coil comprises a plurality of Litz wires.

[0058] Specifically, Litz wire has the advantages of low cost, good conductivity and long life.

[0059] Of course, in addition to Litz wire, the relay coil 1 can also be wires of various other materials, for example, it can be a relay coil 1 processed into a flexible circuit board style, etc., and the embodiment of the present invention is not limited here.

[0060] As a preferred embodiment, the auxiliary charging device also includes:

[0061] The first end is connected to the first end of the first sub-coil 11, and the second end is connected to the first end of the second sub-coil 12. The capacitor is used to form an LC series resonant circuit with the coil to reduce the circuit impedance.

[0062] Specifically, in the LC series resonant circuit, the resonant frequency of the circuit can be adjusted by setting the capacitance of the capacitor. Setting the resonant frequency close to the operating frequency of the transmitting coil can minimize the impedance in the circuit, thereby facilitating the generation of a stronger current under a magnetic field of the same strength, so as to induce a larger current in the receiving coil.

[0063] There may be various types of capacitors, which are not limited in the embodiment of the present invention.

[0064] Of course, in addition to the LC series resonant circuit, the circuit where the relay coil 1 is located can also be other types of circuits with smaller impedance, which is not limited in the embodiment of the present invention.

[0065] As a preferred embodiment, the annular magnetic isolation device 2 includes a plurality of magnetic shielding stickers arranged in an annular shape.

[0066] To better illustrate the embodiments of the present invention, please refer to Figure 3 , Figure 3 A schematic structural diagram of an annular magnetic isolation device provided by the present invention.

[0067] Specifically, since the plurality of magnetic shielding stickers arranged in an annular shape are not continuous, compared with the continuous annular magnetic isolation device 2, the cost is saved, and the production process of the block-shaped magnetic shielding stickers is simple, thus saving the process cost.

[0068] Among them, several magnetic shielding stickers can be arranged in a ring shape evenly and without overlapping to avoid waste of materials.

[0069] Of course, in addition to the above-mentioned styles, the annular magnetic isolation device 2 can also be of other types, which is not limited in the embodiment of the present invention.

[0070] As a preferred embodiment, the magnetic shielding sticker is a ferrite soft magnetic sheet.

[0071] Specifically, ferrite has the advantages of good magnetic isolation effect, low cost and high durability.

[0072] Of course, in addition to ferrite, the magnetic shielding sticker may also be other types, such as nanocrystals, etc., which is not limited in the embodiment of the present invention.

[0073] Of course, the multiple magnetic shielding stickers may be made of different materials or the same material, which is not limited in the embodiment of the present invention.

[0074] In addition, when using ferrite or nanocrystal soft magnetic stickers, since ferrite or nanocrystals have the effect of gathering the magnetic field, which is equivalent to absorbing the surrounding magnetic field to themselves, the soft magnetic stickers arranged in a ring can gather the magnetic field to the center of the ring, thereby enhancing the magnetic field strength in the center of the ring, which is conducive to inducing a larger current in the receiving coil, improving the transmission efficiency, and while ensuring that the receiving end power and the distance between the transmitting coil and the receiving coil remain unchanged, the current and size of the transmitting coil can be reduced, and while ensuring that the current and size of the transmitting coil and the receiving end power remain unchanged, the charging distance can be increased.

[0075] As a preferred embodiment, the inner diameter of the annular magnetic isolation device 2 is greater than a preset value of the outer diameter of the receiving coil.

[0076] Specifically, considering that when a user uses a wireless charger to charge an electronic product, the receiving coil of the electronic product needs to be fitted to the coaxial position of the magnetic shielding device. It is actually impossible for the user to place the electronic device completely coaxially every time. If the inner diameter of the annular magnetic isolation device 2 is equal to the outer diameter of the receiving coil, then the annular magnetic isolation device 2 will isolate the magnetic field inside the receiving coil, affecting the charging effect and wasting energy. Therefore, in an embodiment of the present invention, the inner diameter of the annular magnetic isolation device 2 is larger than the preset value of the outer diameter of the receiving coil. In this case, the user can have a certain redundant placement space when placing the electronic device. Even if the placement is not completely coaxial, the annular magnetic isolation device 2 will not isolate the magnetic field inside the receiving coil to affect the charging effect.

[0077] The preset value may be 10% of the outer diameter of the receiving coil.

[0078] Specifically, setting the preset value to 10% of the outer diameter of the receiving coil can not only provide the user with a certain amount of redundant operating space, but also ensure the magnetic shielding effect.

[0079] Of course, in addition to 10% of the outer diameter of the receiving coil, the preset value may also be other values, which are not limited in the embodiment of the present invention.

[0080] As a preferred embodiment, the fixing device 3 is a packaging shell made of insulating material.

[0081] Specifically, the insulating material can reduce the impact on the electromagnetic induction process and reduce the risk of leakage, while the closed shell can further reduce the risk of leakage and reduce the impact on electromagnetic induction, and has a better fixed protection effect, such as dust and impact protection.

[0082] The insulating material may be of various types, such as plastic, etc., which is not limited in the embodiment of the present invention.

[0083] Of course, in addition to the closed shell made of insulating material, the fixing device 3 can also be of other types, which is not limited in the embodiment of the present invention.

[0084] As a preferred embodiment, the shape of the magnetic shielding sticker is a fan ring.

[0085] The present invention also provides a wireless charger, comprising the auxiliary charging device as described in the above embodiment.

[0086] For an introduction to the wireless charger provided in the embodiment of the present invention, please refer to the aforementioned embodiment of the auxiliary charging device, and the embodiment of the present invention is not limited here.

[0087] Specifically, the fan-shaped magnetic shielding sticker corresponds to the distribution of the magnetic field strength, that is, the farther away from the periphery of the coil center, the weaker the magnetic field strength. The fan-shaped magnetic shielding sticker can correspond to the distribution line of the magnetic field strength. The magnetic field strength at the outermost edge of the fan-shaped ring is almost equal, and materials can be saved while achieving the same magnetic shielding effect.

[0088] Of course, in addition to the fan ring shape, the magnetic shielding sticker can also be in other shapes, which is not limited in the embodiment of the present invention.

[0089] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments, and the same and similar parts between the embodiments can be referred to each other. It should also be noted that in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements includes not only those elements, but also other elements that are not explicitly listed, or also include elements inherent to such process, method, article or equipment. In the absence of more restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the process, method, article or equipment including the element.

[0090] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An auxiliary charging device, applied to a wireless charger, characterized in that: include: A relay coil coaxially arranged between a transmitting coil and a receiving coil of the wireless charger, for inducing alternating current and generating a changing magnetic field inside itself when located in the magnetic field generated by the transmitting coil, so that the receiving coil generates an induced current; An annular magnetic isolation device coaxially arranged on a side of the relay coil that is closer to the receiving coil, for isolating the magnetic field located outside the receiving coil; A fixing device, used for fixing the relay coil and the annular magnetic isolation device; Wherein, the outer diameter of the relay coil is larger than the outer diameter of the receiving coil, and the inner diameter of the annular magnetic isolation device is not smaller than the outer diameter of the receiving coil; The relay coil includes a first sub-coil and a second sub-coil; The first end of the first sub-coil is connected to the first end of the second sub-coil, the second end of the first sub-coil is connected to the first end of the capacitor, and the second end of the second sub-coil is connected to the second end of the capacitor; The first sub-coil and the second sub-coil are co-centered, a preset distance between an outer edge of the first sub-coil and an inner edge of the second sub-coil is greater than zero, and an outer diameter of the first sub-coil is not less than an outer diameter of the receiving coil.

2. The auxiliary charging device according to claim 1, characterized in that: The coil comprises a plurality of strands of Litz wire.

3. The auxiliary charging device according to claim 2, characterized in that: The auxiliary charging device also includes: The first end is connected to the first end of the first sub-coil, and the second end is connected to the first end of the second sub-coil via a capacitor, which is used to form an LC series resonant circuit with the coil to reduce the circuit impedance.

4. The auxiliary charging device according to claim 1, characterized in that: The annular magnetic isolation device comprises a plurality of magnetic shielding stickers arranged in an annular shape.

5. The auxiliary charging device according to claim 4, characterized in that: The magnetic shielding sticker is a ferrite soft magnetic sheet.

6. The auxiliary charging device according to claim 5, characterized in that: The inner diameter of the annular magnetic isolation device is greater than a preset value of the outer diameter of the receiving coil.

7. The auxiliary charging device according to claim 1, characterized in that: The fixing device is a packaging shell made of insulating material.

8. The auxiliary charging device according to any one of claims 4 to 5, characterized in that: The magnetic shielding sticker is in the shape of a fan ring.

9. A wireless charger, characterized in that: Comprising the auxiliary charging device as described in any one of claims 1 to 8.

Images