Wireless charging device
By setting a substrate with a comb filter above the charging coil of the wireless charging device and setting a thermistor in the filter, the problem of electromagnetic interference generated by wireless charging modules in the car is solved, and safety monitoring of the mobile phone charging environment and reduction of electromagnetic interference is achieved.
Patent Information
- Application Number
- CN202311494178.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-11-09
- Publication Date
- 2025-05-13
Smart Images
Figure CN119995181A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a wireless charging device. Background Art
[0002] At present, both electric cars and traditional cars have already put the mobile phone wireless charging module (WCM) into the standard car accessories. Its advantages are that it does not need to be connected to the mobile phone separately and saves the tedious action of plugging in the plug. However, since the mobile phone wireless charging module transmits power at the operating frequency of 112 to 128 kHz (preset to 127.772kHz) defined by Qi, and in the closed and limited space of the car, many electromagnetic interference (EMI) and other problems will naturally occur. Summary of the invention
[0003] In view of the above, the present invention provides a wireless charging device.
[0004] According to an embodiment of the present invention, a wireless charging device comprises a first substrate, at least one charging coil, a second substrate, a comb filter, at least one thermistor, and a controller. The at least one charging coil is disposed on the first substrate. The second substrate is disposed above the at least one charging coil. The comb filter is disposed on the second substrate, and a projection area in a stacking direction at least partially overlaps the at least one charging coil. The at least one thermistor is disposed on the comb filter. The controller is connected to the at least one charging coil, and is connected to the at least one thermistor through a portion of the comb filter.
[0005] Through the above structure, the wireless charging device disclosed in this case can reduce the electromagnetic interference problem that the charging coil may generate to the surrounding environment when charging by setting a substrate with a comb filter above the charging coil. The wireless charging device in this case can sense whether the mobile phone is overheated when charging by setting a thermistor in the comb filter, and because the thermistor is connected to the controller that receives the signal through a part of the comb filter, the overall circuit connection of the wireless charging device is simpler.
[0006] The above description of the disclosed content and the following description of the embodiments are used to demonstrate and explain the spirit and principle of the present invention, and to provide a further explanation of the scope of the patent application of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS
[0007] Figure 1 FIG. 4 is a schematic structural diagram of a wireless charging device according to an embodiment of the present invention.
[0008] Figure 2 It shows an implementation of a charging coil disposed on a first substrate of a wireless charging device according to an embodiment of the present invention.
[0009] Figure 3 It shows an implementation of a comb filter disposed on the second substrate of a wireless charging device according to an embodiment of the present invention.
[0010] Figure 4 It is a schematic diagram showing a charging coil of a wireless charging device disposed on a first substrate according to an embodiment of the present invention.
[0011] Figure 5 FIG. 1 is a schematic diagram of a comb filter disposed on a second substrate of a wireless charging device according to an embodiment of the present invention.
[0012] Figure 6 for Figure 5 A partial enlarged view of area A.
[0013] Figure 7 The diagram shows the corresponding position relationship between the thermistor and the charging coil of a wireless charging device according to an embodiment of the present invention.
[0014] Figure 8 Shown is a plan view of a second substrate of a wireless charging device according to another embodiment of the present invention.
[0015] Fig. 9 FIG. 4 is a schematic structural diagram of a wireless charging device according to another embodiment of the present invention.
[0016] Component number description
[0017] 1 Wireless charging device
[0018] 11. First substrate
[0019] 12. Second substrate
[0020] 121 Page 1
[0021] 122 Second side
[0022] 123 Through Hole
[0023] 13 Charging Coil
[0024] 14 Comb filter
[0025] 141 Comb structure
[0026] 1411 Connection part
[0027] 142 Grounding Structure
[0028] 15 Thermistor
[0029] 16 Controller
[0030] 17 Metal connectors
[0031] 18 Insulation layer
[0032] 19 Near Field Communication Coil
[0033] D Stack direction
[0034] d1 Line width
[0035] d2 Line distance
[0036] A Region DETAILED DESCRIPTION
[0037] The detailed features and advantages of the present invention are described in detail in the following embodiments, and the contents are sufficient to enable any person skilled in the art to understand the technical content of the present invention and implement it accordingly, and according to the contents disclosed in this specification, the scope of the patent application and the drawings, any person skilled in the art can easily understand the relevant purposes and advantages of the present invention. The following examples are used to further illustrate the viewpoints of the present invention in detail, but are not intended to limit the scope of the present invention in any way.
[0038] Please refer to Figure 1 , Figure 1 The figure shows a schematic diagram of the structure of a wireless charging device according to an embodiment of the present invention. Figure 1 As shown, the wireless charging device 1 includes a first substrate 11, a second substrate 12, at least one charging coil 13, a comb filter 14, at least one thermistor 15 and a controller 16. The at least one charging coil 13 is disposed on the first substrate 11. The second substrate 12 is disposed above the at least one charging coil 13. The comb filter 14 is disposed on the second substrate 12, and the projection area in a stacking direction D at least partially overlaps the at least one charging coil 13. The at least one thermistor 15 is disposed on the comb filter 14. The controller 16 is connected to the at least one charging coil 13, and is connected to the at least one thermistor 15 through a portion of the comb filter 14.
[0039] In this example, the second substrate 12 has a first surface 121, a second surface 122 and a plurality of through holes 123, wherein the first surface 121 faces the charging coil 13. The wireless charging coil 1 may further include a plurality of metal connectors 17. The metal connectors 17 are disposed in the plurality of through holes 123, connected to the comb filter 14 and used for grounding, for example, by connecting to the housing ground or to a grounding wire. The metal connectors 17 may also serve as support members for spacing the second substrate 12 and the charging coil 13 from each other. In addition, although the wireless charging device 1 described in this example uses the metal connector 17 to ground the comb filter 14 and support the second substrate 12, in other embodiments, the comb filter 14 may be grounded in other ways, and / or the second substrate 12 and the charging coil 13 may be spaced from each other by other support members.
[0040] The first substrate 11 may include a layer with shielding capability to prevent the charging coil 13 from generating electromagnetic interference to other electronic devices underneath when in operation. Figure 2 , Figure 2 The figure shows an implementation of a charging coil disposed on a first substrate of a wireless charging device according to an embodiment of the present invention. Figure 2 As shown, in this embodiment, the number of charging coils 13 arranged on the first substrate 11 is 1, and the first substrate 11 has a wiring area covered by the charging coil 13 (i.e., an annular area covered by the charging coil 13) and a non-wiring area not covered by the charging coil 13 (i.e., a central area surrounded by the charging coil 13).
[0041] The first surface 121 of the second substrate 12 facing the charging coil 13 is provided with a comb filter 14. Figure 1 and Figure 2 refer to Figure 3 , Figure 3 The figure shows an implementation of a comb filter disposed on the second substrate of a wireless charging device according to an embodiment of the present invention. Figure 3 As shown, the comb filter 14 includes a comb structure 141 and a ground structure 142, and the projection area of the comb structure 141 in the stacking direction D at least partially overlaps the at least one charging coil 13. The ground structure 142 is connected to the comb structure 141 and the metal connector 17, and is located at the periphery of the comb structure 141. The comb structure 141 includes a plurality of wires, and the thermistor 15 is disposed on one of the wires of the comb structure 141, and is preferably disposed above the non-wiring area of the first substrate 11, that is, above the central area surrounded by the charging coil 13.
[0042] The thermistor 15 can produce corresponding changes in resistance value based on the temperature change of the second substrate 12. The thermistor 15 can have a negative temperature coefficient (NTC) or a positive temperature coefficient (PTC), wherein the resistance value of the thermistor with a negative temperature coefficient decreases as the ambient temperature increases, and the resistance value of the thermistor with a positive temperature coefficient increases as the ambient temperature increases. The thermistor 15 described below is based on the type with a negative temperature coefficient, but the present case is not limited to this. The controller 16 can have data receiving, recording, computing, storage and output functions, for example, including a microcontroller, a central processing unit, a programmable logic controller, etc. The controller 16 is connected to the thermistor 15 through a connecting portion 1411 of the comb structure 141 to read the resistance value change of the thermistor 15, and obtain the current temperature of the second substrate 12 accordingly. When the controller 16 determines that the current temperature of the second substrate 12 is greater than a default temperature, it means that the temperature of the mobile phone waiting to be charged is too high, and the controller 16 can control the charging coil to reduce the charging power or stop charging.
[0043] The present invention does not limit the number of charging coils and thermistors, but preferably, the number of thermistors and the number of charging coils can be the same. The number of thermistors and charging coils described below is 3 as an example. Figure 4 , Figure 4 The figure shows a schematic diagram of a charging coil of a wireless charging device disposed on a first substrate according to an embodiment of the present invention. Figure 4 As shown, the number of charging coils 13 arranged on the first substrate 11 is three, and the first substrate 11 has a wiring area covered by the charging coils 13 (corresponding to the annular area of the three charging coils 13) and a non-wiring area not covered by the charging coils 13 (corresponding to the area of the three charging coils 13 that do not overlap with each other).
[0044] Please combine Figure 1 and Figure 4 refer to Figure 5 , Figure 5 The figure shows a schematic diagram of a comb filter disposed on a second substrate of a wireless charging device according to an embodiment of the present invention. Figure 5As shown, the comb filter 14 includes a comb structure 141 and a ground structure 142, and the projection area of the comb structure 141 in the stacking direction D at least partially overlaps the three charging coils 13. The ground structure 142 is connected to the comb structure 141 and the metal connector 17, and is located at the periphery of the comb structure 141. The comb structure 141 includes a plurality of wires, and three thermistors 15 are respectively arranged on three of the wires of the comb structure 141, and are preferably arranged above the non-wiring area of the first substrate 11, that is, each corresponds to a charging coil 13. The controller 16 is connected to the thermistor 15 through a connecting portion 1411 of the comb structure 141 to read the resistance value change of each thermistor 15, and obtain the current temperature of multiple (three) local areas of the second substrate 12 accordingly. When the controller 16 determines that the current temperature of any local area of the second substrate 12 is greater than a default temperature, it means that the temperature of the mobile phone waiting for charging device is too high, and the controller 16 can control the charging coil to reduce the charging power or stop charging.
[0045] The line width and line spacing of the comb-shaped structure 141 may be related to the frequency of the wireless charging signal emitted by the charging coil 13. Figure 6 , Figure 6 for Figure 5 A partial enlarged view of area A. Figure 6 As shown, the wires of the comb structure 141 have a line width d1, and there is a line distance d2 between adjacent wires. The line width d1 and line distance d2 of the comb structure 141 can be related to the frequency of the wireless charging signal emitted by the charging coil 13. For example, the line width d1 can be 13 mm, and the line distance d2 can be 17 mm. Please refer to Table 1, which shows the filtering effect of different line widths d1 and line distances d2 of the comb structure 141 corresponding to signals of different frequencies.
[0046] Table 1. Filtering effect table corresponding to different line widths and line spacings
[0047] Line width / line spacing 0.64MHz 0.85MHz 1.14MHz 1.34MHz NA -6.2dB -3.64dB -9.72dB -8.02dB 13mm / 17mm -10.64dB -8.34dB -11.12dB -19.77dB 10mm / 20mm -9.4dB -6.76dB -8.23dB -14.46dB 10mm / 15mm -10.4dB -10.1dB -17.15dB -12.04dB
[0048] As shown in Table 1, the first column is the case where the comb filter of the present invention is not used (NA). In this case, the worst filtering effect is achieved for charging signals of various frequencies. The second column is the case where the line width of the comb filter 141 is 13 mm and the line spacing is 17 mm. In this case, the best filtering effect is achieved for charging signals with a frequency of 1.34 MHz. The third column is the case where the line width of the comb filter 141 is 10 mm and the line spacing is 20 mm. In this case, the overall filtering effect is slightly lower than the case where the line width / line spacing is 13 / 17 mm, but filtering can still be performed effectively. The fourth column is the case where the line width of the comb filter 141 is 10 mm and the line spacing is 15 mm. In this case, the best filtering effect is achieved for charging signals with frequencies of 0.85 and 1.14 MHz. Accordingly, the comb filter of the present invention can design and adjust the line width and line spacing of the comb structure according to the frequency range of the wireless charging signal in actual application to optimize the filtering effect. In addition, the above test safety regulations are CISPR 25Class 3.
[0049] Please combine Figure 4 and Figure 5 refer to Figure 7 , Figure 7 The figure shows the corresponding position relationship between the thermistor and the charging coil of the wireless charging device according to one embodiment of the present invention. Figure 7 As shown, the projections of the three charging coils 13 on the first substrate 11 on the first surface 121 of the second substrate 12 in the aforementioned stacking direction are completely covered by the comb structure 141 and the grounding structure 142 of the comb filter 14. In this way, the comb filter 14 can better filter the charging coils 13. Further, the three thermistors 15 are arranged to be located above the aforementioned non-wiring area, and are respectively located above a central area of the first substrate surrounded by each of the three charging coils. It should be noted that the thermistor 15 in this figure is also as shown in FIG. Figure 5 As shown, it is connected to the controller 16 through a part of the comb structure, and its repeated description and illustration are omitted here. Through this configuration, no matter the device to be charged (such as a mobile phone) is placed above or below the second substrate 12, the charging coil at the corresponding position can charge it wirelessly. When the device to be charged is overheated, the thermistor 15 at the corresponding position can also sense its temperature change more accurately, and allow the controller to obtain the resistance value change associated with the temperature change.
[0050] Please refer to Figure 8 , Figure 8 The figure shows a plan view of the second substrate of the wireless charging device according to another embodiment of the present invention. In this example, the wireless charging device may further include a near field communication antenna 19, which is disposed on the second surface 122 of the second substrate 12 opposite to the comb filter and connected to the controller 16. Figure 8 As shown, the near field communication coil 19 is located outside the three charging coils 13 along the projection of the first substrate below, that is, the projection area of the near field communication antenna 19 on the first substrate along the aforementioned stacking direction does not overlap with the three charging coils 13, so that the wireless charging signal of the charging coil 13 is less likely to affect the operation of the near field communication coil 19. Specifically, the near field communication coil 19 of this example has a two-circle graphic structure, in which the line width is 50 mm and the line spacing is 6 mm. Furthermore, after the near field communication coil 19 is controlled by impedance matching at 13.56 MHz, it can have a card reading distance of more than 5 cm for cards with various near field communication chips, and allow the controller 16 to obtain the card reading signal.
[0051] When the controller 16 obtains the card reading signal, it can be determined that the device to be charged (such as a mobile phone) is being charged, and other cards with near-field communication chips may be placed in its vicinity. Therefore, the controller 16 can control the charging coil 13 to stop charging to prevent the charging signal from damaging the near-field communication chip on the card. It should be noted that this embodiment may include the application of the aforementioned embodiment, that is, the controller 16 can determine whether the current temperature of the second substrate 12 is greater than a default temperature through a thermistor, and control the charging coil to reduce the charging power or stop charging when the temperature is too high to prevent the device to be charged from being damaged by overheating; on the other hand, the controller can obtain the card reading signal through the near-field communication coil 19, and control the charging coil 13 to stop charging when the card reading signal is obtained to prevent the charging signal from damaging the near-field communication chip on the card.
[0052] Please refer to Fig. 9 , Fig. 9 The figure shows a schematic diagram of the structure of a wireless charging device according to another embodiment of the present invention. Fig. 9 As shown, the wireless charging device 1' of this example includes, in addition to a first substrate 11, a second substrate 12, at least one charging coil 13, a comb filter 14, a thermistor (not shown) and a controller (not shown), an insulating layer 18 disposed between the at least one charging coil 13 and the comb filter 14. By disposing the insulating layer 18, the second substrate 12 and the comb filter 14 can be supported on the charging coil 13, and the comb filter 14 and the charging coil 13 are electrically isolated.
[0053] Through the above structure, the wireless charging device disclosed in this case can reduce the electromagnetic interference problem that the charging coil may cause to the surrounding environment when charging by setting a substrate with a comb filter above the charging coil. The wireless charging device in this case can sense whether the mobile phone is overheated when charging by setting a thermistor in the comb filter, and because the thermistor is connected to the controller that receives the signal through a part of the comb filter, the overall line connection of the wireless charging device is simpler. In addition, the wireless charging device in this case can detect whether there are other cards with near-field communication chips close to the charging range of the wireless charging coil by setting a near-field communication coil on the side of the second substrate opposite to the comb filter, so as to avoid damage to the near-field communication chip on the card by the charging signal during the charging process.
[0054] In one embodiment of the present invention, the wireless charging device of the present invention can be applied to a vehicle-mounted device, such as a self-driving car, an electric car, or a semi-self-driving car.
[0055] Although the present invention is disclosed as above with the aforementioned embodiments, it is not intended to limit the present invention. Without departing from the spirit and scope of the present invention, all changes and modifications are within the scope of patent protection of the present invention. Please refer to the attached patent application for the scope of protection defined by the present invention.
Claims
1. A wireless charging device, characterized in that: Include: a first substrate; at least one charging coil, disposed on the first substrate; a second substrate, disposed above the at least one charging coil; a comb filter, disposed on the second substrate, and having a projection area in a stacking direction at least partially overlapping the at least one charging coil; At least one thermistor, disposed in the comb filter; as well as A controller is connected to the at least one charging coil and is connected to the at least one thermistor through a portion of the comb filter.
2. The wireless charging device according to claim 1, characterized in that: The comb filter comprises: a comb-shaped structure, the projection area of which in the stacking direction at least partially overlaps with the at least one charging coil; and A grounding structure is connected to the comb-shaped structure and is located outside the comb-shaped structure.
3. The wireless charging device according to claim 2, characterized in that: The line width and line distance of the comb structure are related to the frequency of the wireless charging signal emitted by the at least one charging coil.
4. The wireless charging device according to claim 2, characterized in that: The second substrate has a plurality of through holes, and the wireless charging device further comprises: A plurality of metal connectors are disposed in the plurality of through holes, connected to the grounding structure, and used for grounding.
5. The wireless charging device according to claim 1, characterized in that: The comb filter is disposed on a side of the second substrate facing the at least one charging coil, the second substrate has a plurality of through holes, and the wireless charging device further comprises: A plurality of metal connecting members are disposed in the through hole and space the second substrate and the at least one charging coil apart from each other.
6. The wireless charging device according to claim 1, characterized in that: The comb filter is disposed on a side of the second substrate facing the at least one charging coil, and the wireless charging device further comprises: An insulating layer is disposed between the at least one charging coil and the comb filter.
7. The wireless charging device according to claim 1, characterized in that: The first substrate has a wiring area covered by the at least one charging coil and a non-wiring area not covered by the at least one charging coil, and the at least one thermistor is disposed above the non-wiring area.
8. The wireless charging device according to claim 1, characterized in that: The number of the at least one thermistor is the same as the number of the at least one charging coil, and the at least one thermistor is disposed above a central area surrounded by each of the at least one charging coil.
9. The wireless charging device according to claim 1, characterized in that: Also includes: A near field communication antenna is disposed on a side of the second substrate opposite to the comb filter and connected to the controller.
10. The wireless charging device according to claim 9, characterized in that: A projection area of the near field communication antenna on the first substrate along the stacking direction does not overlap with the at least one charging coil.