Wireless charging foreign matter detection circuit module and charging device

Abstract

The utility model relates to the application field of electromagnetic induction, in particular to a wireless charging foreign matter detection circuit module and a charging device, and the wireless charging foreign matter detection circuit module comprises a PCB, an annular coil, a rectification circuit and a main control unit. The annular coils are uniformly distributed on the PCB, and the rectifying circuit is connected with the annular coils; the main control unit is connected with the rectifying circuit; when no foreign matter exists above the annular coil, the main control unit controls the transmitting coil to generate an electromagnetic field, the annular coil induces a current signal and then forms a voltage signal through the rectifying circuit to be transmitted to the main control unit, and the main control unit records the voltage signal at the moment as a threshold value. During normal work, if a small metal foreign matter is placed in a certain area of the annular coil, resonance parameters of the corresponding area are affected, and current signals of the corresponding area are inconsistent with current signals not affected by the metal foreign matter. Therefore, existence of metal foreign matters in the charging area can be judged and an alarm is given out.

Description

Technical Field

[0001] The utility model relates to the application field of electromagnetic induction, and in particular to a wireless charging foreign body detection circuit module and a charging device. Background Art

[0002] Wireless charging technology mainly uses the principle of electromagnetic induction. The transmitting device converts electrical energy into magnetic field energy, and the receiving device converts the magnetic field energy into electrical energy to complete the energy transmission. Wireless charging has the characteristics of charging at any time, no buckle, and strong versatility. It is increasingly liked and used by consumers. At present, the wireless charging function has become an indispensable function in the mobile phone market.

[0003] Wireless charging has the feature of charging at any time, but it also brings potential safety risks that other charging methods do not have. For example, if a metal foreign object is accidentally caught between the transmitter and the receiver, the metal foreign object will heat up. If the system does not recognize the metal foreign object and continues to work, the temperature of the metal foreign object will continue to rise, causing safety risks.

[0004] At present, the mainstream wireless charging foreign body detection methods are divided into Q value detection and efficiency judgment. For some large metal foreign bodies, these two methods are relatively effective and can easily detect foreign bodies. However, for some small metal foreign bodies, in order to ensure the compatibility of different receiving ends, the system cannot set the Q value and efficiency judgment threshold too strictly, which will lead to the inability to identify these small foreign bodies, which will cause safety hazards. Utility Model Content

[0005] The purpose of the utility model is to provide a wireless charging foreign object detection circuit module and a charging device to solve the problems in the above-mentioned background technology.

[0006] To achieve the above-mentioned purpose, the technical solution adopted by the utility model is to provide a wireless charging foreign object detection circuit module, including a PCB board, a ring coil, a rectifier circuit and a main control unit, the PCB board is of a regular shape; the ring coil is multiple and evenly distributed on the PCB board, the ring coil includes a ring part and a lead-out part, the ring part is formed by multiple layers of conductive wire, including an inner ring end and an outer ring end, the lead-out part includes a first lead-out part and a second lead-out part, the first lead-out part is connected to the inner ring end, the second lead-out part is connected to the outer ring end, the first lead-out part and the second lead-out part can be connected to form a closed loop; the rectifier circuit is connected to the ring coil; the main control unit is connected to the rectifier circuit; the ring coil senses a current signal, the current signal forms a voltage signal after passing through the rectifier circuit, and the voltage signal is then transmitted to the main control unit.

[0007] Furthermore, the plurality of annular wires are arranged in close proximity to each other, so that there is no blank area on the PCB board.

[0008] Furthermore, the PCB board is circular, and the annular coil includes a central coil and a peripheral coil. The central coil is located at the center of the PCB board, and the peripheral coil is distributed around the central coil.

[0009] Furthermore, the peripheral coil is only one layer and is distributed around the central coil.

[0010] Furthermore, there are four peripheral coils, the central coil is in a circular ring shape, and the peripheral coils are in a fan ring shape.

[0011] Furthermore, the annular coil is a copper-clad coil.

[0012] Furthermore, the PCB board is copper-clad on both sides, the first lead-out portion is located on the front side of the PCB board, and the second lead-out portion is located on the back side of the PCB board.

[0013] Furthermore, the present application also provides an electrical device, comprising any one of the wireless charging foreign object detection circuit modules described above.

[0014] The beneficial effects of the utility model are:

[0015] 1. When there is no foreign object above the toroidal coil, the main control controls the transmitting coil to generate an electromagnetic field. After the toroidal coil senses the current signal, it forms a voltage signal through the rectifier circuit and transmits it to the main control unit. The main control unit records the voltage signal at this time as the threshold. During normal operation, if a small metal foreign object is placed in a certain area on the toroidal coil, it will affect the resonance parameters of the corresponding area, resulting in inconsistency between the current signal in the corresponding area and the current signal without the influence of metal foreign objects. When the main control unit detects that the signal strength of multiple rings is inconsistent and reaches a certain difference, it can be judged that there is a metal foreign object in the charging area, and the wireless charging can be stopped in time and a warning can be issued, effectively eliminating safety hazards.

[0016] 2. Multiple circular wires are closely fitted together to ensure that there is no blank area on the PCB board, thus preventing the detection circuit module from having a blank area and failing to effectively detect metal foreign objects.

[0017] 3. The PCB board of this product is circular, and the annular coil includes a central coil and a peripheral coil. There are four peripheral coils distributed around the central coil. The central coil is in a circular ring shape, and the peripheral coil is in a fan ring shape, which is convenient for multiple annular wires to be closely fitted. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific implementation methods of the utility model or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 A schematic structural diagram of a wireless charging foreign object detection circuit module provided in an embodiment of the utility model.

[0020] Description of reference numerals:

[0021] 1. PCB board; 21. center coil; 22. peripheral coil; 231. inner ring end; 232. outer ring end; 241. first lead-out portion; 242. second lead-out portion. DETAILED DESCRIPTION

[0022] The technical solution of the utility model will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0023] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0024] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0025] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0026] Example 1

[0027] Reference Figure 1 As a wireless charging foreign object detection circuit module provided by an embodiment of the utility model, it includes a PCB board 1, a ring coil, a rectifier circuit and a main control unit. The PCB board 1 is in a regular shape; there are multiple ring coils and they are evenly distributed on the PCB board 1. The ring coil includes a ring part and a lead-out part. The ring part is formed by multiple layers of conductive wire, including an inner ring end 231 and an outer ring end 232. The lead-out part includes a first lead-out part 241 and a second lead-out part 242. The first lead-out part 241 is connected to the inner ring end 231, and the second lead-out part 242 is connected to the outer ring end 232. The first lead-out part 241 and the second lead-out part 242 can be connected to form a closed loop; the rectifier circuit is connected to the ring coil; the main control unit is connected to the rectifier circuit; the ring coil senses a current signal, and the current signal forms a voltage signal after passing through the rectifier circuit, and the voltage signal is then transmitted to the main control unit.

[0028] When there is no foreign object above the toroidal coil, the main control controls the transmitting coil to generate an electromagnetic field. After the toroidal coil senses the current signal, it forms a voltage signal through the rectifier circuit and transmits it to the main control unit. The main control unit records the voltage signal at this time as the threshold. During normal operation, if a small metal foreign object is placed in a certain area on the toroidal coil, it will affect the resonance parameters of the corresponding area, resulting in inconsistency between the current signal in the corresponding area and the current signal without the influence of metal foreign objects. When the main control unit detects that the signal strength of multiple rings is inconsistent and reaches a certain difference, it can be judged that there is a metal foreign object in the charging area, and the wireless charging can be stopped in time and a warning can be issued, effectively eliminating safety hazards.

[0029] Specifically, the PCB board 1 is in a regular shape, which facilitates the close fitting of multiple annular coils, so that there is no blank area on the PCB board 1. It prevents the detection circuit module from having a blank area and failing to effectively detect metal foreign matter. The PCB board 1 is a printed circuit board, and the annular coil is a copper-clad coil. The PCB board 1 is copper-clad on both sides, the first lead-out portion 241 is located on the front side of the PCB board 1, and the second lead-out portion 242 is located on the back side of the PCB board 1. The copper-clad coil can be routed from the back to form a closed ring. The rectifier circuit is a circuit that converts AC power into DC power. The function of the rectifier circuit is to convert the AC power with a lower voltage output by the AC step-down circuit into unidirectional pulsating DC power. This is the rectification process of AC power. The rectifier circuit is mainly composed of rectifier diodes. The voltage after the rectifier circuit is no longer an AC voltage, but a mixed voltage containing DC voltage and AC voltage. The main control unit uses a main control chip, which is an integrated circuit that integrates a processor, input and output (I / O) ports, memory and other peripheral devices. The main control chip is responsible for scheduling various functional modules and is the core component of device control.

[0030] Furthermore, the PCB board 1 is circular, and the annular coil includes a central coil 21 and a peripheral coil 22 . The central coil 21 is located at the center of the PCB board 1 , and the peripheral coil 22 is distributed around the central coil 21 .

[0031] Specifically, the PCB board 1 is circular, so that the PCB board 1 is smaller in size and more beautiful in appearance while meeting the functional requirements. In order to eliminate the blank area on the circular PCB board 1, the annular coil includes a central coil 21 and a peripheral coil 22, and the central coil 21 is located at the center of the PCB board 1, and the central coil 21 is annular. There are four peripheral coils 22, and the peripheral coils 22 are only one layer and are distributed around the central coil 21. The peripheral coils 22 are fan-shaped. The central coil 21 is annular, and the peripheral coils 22 are fan-shaped, so that multiple annular wires can be closely fitted and arranged, so that there is no blank area on the PCB board 1, and the detection circuit module is prevented from detecting blank areas and failing to effectively detect metal foreign matter.

[0032] Example 2

[0033] A charging device provided as an embodiment of the utility model includes the wireless charging foreign object detection circuit module described in Embodiment 1.

[0034] When there is no foreign object above the toroidal coil, the main control controls the transmitting coil to generate an electromagnetic field. After the toroidal coil senses the current signal, it forms a voltage signal through the rectifier circuit and transmits it to the main control unit. The main control unit records the voltage signal at this time as the threshold. During normal operation, if a small metal foreign object is placed in a certain area on the toroidal coil, it will affect the resonance parameters of the corresponding area, resulting in inconsistency between the current signal in the corresponding area and the current signal without the influence of metal foreign objects. When the main control unit detects that the signal strength of multiple rings is inconsistent and reaches a certain difference, it can be judged that there is a metal foreign object in the charging area, and the wireless charging can be stopped in time and a warning can be issued, effectively eliminating safety hazards.

[0035] The product is a circular PCB board 1, and the annular coil includes a central coil 21 and a peripheral coil 22. The peripheral coils 22 are four and are distributed around the central coil 21. The central coil 21 is annular, and the peripheral coils 22 are fan-shaped, which facilitates the close fitting of multiple annular wires. The embodiments of this specific implementation are all preferred embodiments of the utility model, and the protection scope of the utility model is not limited thereto. Therefore, all equivalent changes made according to the structure, shape, and principle of the utility model should be covered within the protection scope of the utility model.

Claims

1. A wireless charging foreign object detection circuit module, characterized in that: include: A PCB board (1), wherein the PCB board (1) is in a regular shape; A plurality of annular coils are evenly distributed on a PCB board (1), the annular coil comprising an annular portion and an output portion, the annular portion being formed by multiple layers of conductive wires, comprising an inner ring end portion (231) and an outer ring end portion (232), the output portion comprising a first output portion (241) and a second output portion (242), the first output portion (241) being connected to the inner ring end portion (231), the second output portion (242) being connected to the outer ring end portion (232), the first output portion (241) and the second output portion (242) being connectable to form a closed loop; A rectifier circuit connected to the annular coil; A main control unit connected to the rectifier circuit; The annular coil senses a current signal, and the current signal forms a voltage signal after passing through the rectifier circuit, and the voltage signal is then transmitted to the main control unit.

2. The wireless charging foreign object detection circuit module according to claim 1, characterized in that: The plurality of annular coils are arranged in close proximity, so that there is no blank area on the PCB board (1).

3. The wireless charging foreign object detection circuit module according to claim 2, characterized in that: The PCB board (1) is circular, and the annular coil comprises a central coil (21) and a peripheral coil (22); the central coil (21) is located at the center of the PCB board (1), and the peripheral coil (22) is distributed around the central coil (21).

4. The wireless charging foreign object detection circuit module according to claim 3, characterized in that: The outer coil (22) is only one layer and is distributed around the central coil (21).

5. The wireless charging foreign object detection circuit module according to claim 4, characterized in that: There are four peripheral coils (22), the central coil (21) is in a circular ring shape, and the peripheral coils (22) are in a fan ring shape.

6. The wireless charging foreign object detection circuit module according to claim 1, characterized in that: The annular coil is a copper-clad coil.

7. The wireless charging foreign object detection circuit module according to claim 6, characterized in that: The PCB board (1) is copper-clad on both sides, the first lead-out portion (241) is located on the front side of the PCB board (1), and the second lead-out portion (242) is located on the back side of the PCB board (1).

8. A charging device, characterized in that: The invention comprises a wireless charging foreign object detection circuit module as described in any one of claims 1 to 7.

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