WO2019219754A1

WO2019219754A1 - Inductive charging antenna structure, wireless charging module and motor vehicle

Info

Publication number: WO2019219754A1
Application number: PCT/EP2019/062493
Authority: WO
Inventors: Stéphane SCHULER; Bin Yao
Original assignee: Valeo Comfort And Driving Assistance
Priority date: 2018-05-17
Filing date: 2019-05-15
Publication date: 2019-11-21

Abstract

An inductive charging antenna structure is provided. The inductive charging antenna structure includes: a printed circuit board populated with electrical components that control inductive charging operation; an inductive charging antenna coil assembly including at least one coil; and a coil assembly printed circuit board. The inductive charging antenna coil assembly is placed between the printed circuit board and the coil assembly printed circuit board, and the at least one coil of the inductive charging antenna coil assembly is electrically and mechanically connected to the coil assembly printed circuit board, and electrically connected to the main printed circuit board through the coil assembly printed circuit board. A wireless charging module including the inductive charging antenna structure and a motor vehicle including the wireless charging module are also provided.

Description

INDUCTIVE CHARGING ANTENNA STRUCTURE, WIRELESS CHARGING MODULE

AND MOTOR VEHICLE

TECHNICAL FIELD

Embodiments of the present disclosure relate to an inducti ve charging antenna structure, a wireless charging module including such an inductive charging antenna structure and a motor vehicle including such a wireless charging module.

BACKGROUND

Wireless energy transfer refers to a contactless energy transfer between a transmitter and a receiver. Wireless chargers using wireless energy transmission are increasingly popular electronic applications. In an automotive environment, electrical wiring could be seen as a hazard to the drive when, for example, the electrical wiring gets entangled in the steering wheel.

An inductive charging antenna structure of a wireless charging module may include a main printed circuit board (PCB) provided with electrical components that control the operations of an inductive charging antenna, a charging antenna coil assembly electrically and mechanically connected to the main printed circuit board, and a separated grounded shielding plate located between the charging antenna coil assembly and the main printed circuit board. Such an inductive charging antenna structure has a relatively complicated structure that is costly to assemble.

SUMMARY

Some embodiments of the present disclosure provide an inductive charging antenna structure. The inductive charging antenna structure includes: a main printed circuit board provided with electrical components that control an inductive charging process; an inductive charging antenna coil assembly including at least one coil; a magnetic insulation sheet located between the main printed PCB and the inductive charging antenna coil assembly; and a coil assembly printed circuit board. The inductive charging antenna coil assembly is located between the main printed circuit board and the coil assembly printed circuit board. The at least one coil of the inductive charging antenna coil assembly is electrically and mechanically connected to the coil assembly printed circuit board, and is further electrically connected to the main printed circuit board. The at least one coil may be placed in contact or at a distance from the magnetic insulation sheet; a rounded metal shield may be optionally located in the structure between the main printed circuit board and the magnetic insulation sheet. As an example, in some embodiments, the at least one coil of the inductive charging antenna coil assembly is electrically connected to the main printed circuit board through the coil assembly printed circuit board.

As an example, in some embodiments, a surface area of coil assembly printed circuit board is designed in such a way the coil assembly printed circuit board is capable of carrying the entire inductive charging antenna coil assembly.

As an example, in some embodiments, the at least one coil is suspended at the distance away from the magnetic insulation sheet by the coil assembly printed circuit board.

As an example, in some embodiments, the inductive charging antenna structure further includes a spacer, wherein the spacer is placed between the magnetic insulation sheet and the at least one coil to support the at least one coil over the magnetic insulation sheet.

As an example, in some embodiments, the inductive charging antenna structure further includes an over-molded portion, at least partially over-molding the at least one coil, wherein at least a portion of the over-molded portion is located between the at least one coil and the magnetic insulation sheet to support the at least one coil over the magnetic insulation sheet.

As an example, in some embodiments, the at least one coil is placed at a distance ranging from 0.3 to 2.5mm to the magnetic insulation sheet.

As an example, in some embodiments, the magnetic insulation sheet is a rigid or flexible type ferrite sheet.

As an example, in some embodiments, the inductive charging antenna structure further includes at least one temperature sensing element. Each temperature sensing element is surface- assembled on a side of the coil assembly printed circuit board where the inductive charging antenna coil assembly is located or on a side of the main printed circuit board facing the inductive charging antenna coil assembly

As an example, in some embodiments, the temperature sensing element is a negative temperature coefficient element.

As an example, in some embodiments, the coil assembly printed circuit board includes a re-radiation pattern laid out on at least one layer of the coil assembly printed circuit board, designed to attenuate an electric field radiation while allowing a magnetic field to pass through the coil assembly printed circuit board.

As an example, in some embodiments, the re-radiation antenna printed circuit board is grounded. As an example, in some embodiments, the coil assembly printed circuit board includes on one or more layers for a near field communication antenna, a Bluetooth antenna, a WIFI antenna, or a long term evolution repeater.

As an example, in some embodiments, the coil assembly printed circuit board is populated with electrical components to at least partially control a near field communication antenna, a Bluetooth antenna, a WIFI antenna, a long term evolution repeater, or to realize a backlight function.

As an example, in some embodiments, the at least one coil of the inductive charging antenna coil assembly is electrically and mechanically connected to the coil assembly printed circuit board by welding or via an interconnecting part of the at least one coil to a mating interconnecting part of the coil assembly printed circuit board.

Some embodiments of the present disclosure provide a wireless charging module including the inductive charging antenna structure as described above.

As an example, in some embodiments, the wireless charging module further includes an electrical connector for connecting the wireless charging module to a motor vehicle electrical system.

As an example, in some embodiments, the electrical connector and other electrical components of the main printed circuit board are placed on a side of the printed circuit board facing away from the inductive charging antenna coil assembly.

Some embodiments of the present disclosure provide a motor vehicle including the wireless charging module as described above.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to clearly illustrate the technical solutions of the embodiments of the disclosure, the drawings of the embodiments will be briefly described in the following; it is obvious that the drawings described below are only related to some embodiments of the disclosure and thus are not limitative of the disclosure.

Figure 1 shows an exploded perspective view of an inductive charging antenna structure according to an embodiment of the invention;

Figure 2 shows a partial cutaway view of the assembled inductive charging antenna structure according to an embodiment of the present disclosure;

Figure 3 shows a bottom partial exploded view of the inductive charging antenna structure according to an embodiment of the present disclosure; Figure 4 is a perspective view of an inductive charging antenna structure according to another embodiment of the present disclosure;

Figure 5 is a side view of the inductive charging antenna structure of Figure 4;

Figure 6 is a diagram showing a variation of a quality factor of an inductive charging antenna structure as a function of a distance between an inductive charging antenna coil and a magnetic insulation sheet according to an embodiment of the present disclosure;

Figure 7 is a perspective view of an inductive charging antenna structure according to another embodiment of the present disclosure;

Figure 8 is a side view of the inductive charging antenna structure of Figure 7;

Figure 9 is a perspective view of an inductive charging antenna structure according to another embodiment of the present disclosure.

DETAILED DESCRIPTION

In order to make objects, technical details and advantages of the embodiments of the disclosure apparent, the technical solutions of the embodiment will be described in a clearly and fully understandable way in connection with the drawings related to the embodiments of the disclosure. It is obvious that the described embodiments are just a part but not all of the embodiments of the disclosure. Based on the described embodiments herein, those skilled in the art can obtain other embodiment(s), without any inventive work, which should be within the scope of the disclosure.

Unless otherwise defined, technical terms or scientific terms used in the present disclosure are intended to be understood in the ordinary meaning of the ordinary skill of the art. The words "first", "second", and similar terms used in the present disclosure do not indicate any order, quantity, or importance, but are used to distinguish different components. Similarly, the words "a", "an", "the” or the like does not indicate a quantity limit, but indicate“at least one”. The words "include", "include" or the like means that the elements or items preceding the words contain the elements or items after the words and their equivalents, but do not exclude other elements or items. The words "connect", "interconnect" or the like are not limited to physical or mechanical connections, but may include electrical connections, either directly or indirectly. The words "upper", "lower", "left", "right" and the like are only used to indicate the relative positional relationships, and when the absolute position of the object described is changed, the relative positional relationship may also change accordingly.

At least one embodiment of the present application provides an inductive charging antenna structure including: a main printed circuit board populated with electrical components that controls an inductive charging process; an inductive charging antenna coil assembly including at least one coil; a magnetic insulation sheet; and a coil assembly printed circuit board. The magnetic insulation sheet is located between the main printed PCB and the inductive charging antenna coil assembly. The inductive charging antenna coil assembly is placed between the printed circuit board and the coil assembly printed circuit board. The at least one coil of the inductive charging antenna coil assembly is electrically and mechanically connected to the coil assembly printed circuit board, and is further electrically connected to the main printed circuit board.

Due to the magnetic insulation sheet and, in some cases, the shielding plate to carry it that are both located between the main PCB and the inductive charging antenna coil assembly, the direct electrical connection and direct mechanical connection of the at least one coil to the main PCB will result in a complex assembly and a high cost. Since the at least one coil of the inductive charging antenna assembly is electrically connected and mechanically connected to the coil assembly printed circuit board, the at least one coil does not have to be directly connected to the main PCB, thereby simplifying the assembly and reducing the cost. For example, in some embodiments, the at least one coil of the inductive charging antenna coil assembly is electrically connected to the main PCB through the coil assembly printed circuit board.

Additionally, thanks to the electrical and mechanical connection of the at least one coil of the inductive charging antenna assembly to the coil assembly printed circuit board, the inductive charging antenna coil assembly may first be connected to the coil assembly printed circuit board and only later to the main PCB, during the fabricating process of the inductive charging antenna structure. Thereby, the assembly of the inductive charging antenna structure is simplified.

In some embodiments, the coil assembly printed circuit board may include a re -radiation pattern. The re-radiation pattern is designed to attenuate an electric field radiation while allowing a magnetic field to pass through the re-radiation antenna printed circuit board. Thus, the inductive charging antenna structure according to the embodiments of the present disclosure shields radiations of harmful electromagnetic waves emitted by the inductive charging antenna printed circuit board without significantly affecting the magnetic field required to realize an inductive charging function.

Figure 1 shows an exploded perspective view of an inductive charging antenna structure 100 according to an embodiment of the present disclosure. The inductive charging antenna structure 100 includes a main printed circuit board (PCB) 110, an inductive charging antenna coil assembly 120, a coil assembly printed circuit board 130 placed generally in parallel to one another. The inductive charging antenna coil assembly 120 is positioned between the main PCB 110 and the coil assembly printed circuit board 130.

The main PCB 110 is populated with electrical components (not shown) that control the operation of the inductive charging antenna. These electrical components and the main PCB 110 form a printed circuit board assembly (PCB A). The main PCB 110 has a first side facing the inductive charging antenna coil assembly 120 and a second side that is opposite to the first side. Preferably, the electrical components are all placed on the second side of the PCB 110, i.e., on the side opposite to the side facing the inductive charging antenna coil assembly 120, to reduce an overall thickness of the inductive charging antenna structure 100 and shield them from magnetic radiations that could affect their operation.

The main printed circuit board 110 may be a single layer printed circuit board or a multilayer printed circuit board. Practically, for proper shielding, the outer layer opposite the component side should be laid out as a GND plane to further shield the electronics.

The inductive charging antenna coil assembly 120 includes at least one coil 150. In one embodiment, the inductive charging antenna coil assembly 120 includes three coils 150 with two of the coils 150 provided in a single plane, side by side and a third coil 150 stacked on the other two coils 150. The coil 150 may be a flat stamped coil (e.g. a coil as described in WO2015/077782A1) in order to reduce a volume of the antenna structure, but may also be in other forms, for example in a form of a Litz wire.

In the present embodiment, the inductive charging antenna coil assembly 120 is electrically and mechanically connected to the coil assembly printed circuit board 130, that is in turn electrically connected to the main PCB 110 through a separate interconnector (not shown). The inductive charging antenna coil assembly 120 is not directly electrically connected to the main PCB 110.

Specifically, the coil 150 of the inductive charging antenna coil assembly 120 is electrically and mechanically connected to the coil assembly printed circuit board 130 through an appropriate soldering method. Alternatively, the coil 150 may have an interconnecting part which is complementary to a mating interconnecting part of the coil assembly printed circuit board 130. By means of the interconnecting part and the mating interconnecting part, the coil 150 is electrically and mechanically connected to the coil assembly printed circuit board 130. For example, the coil 150 may include a coil body with electrical and mechanical connecting terminals. The coil 150 is electrically and mechanically connected to the mating electrical and mechanical connecting terminals of the coil assembly printed circuit board 130 through the electrical and mechanical connecting terminals. In addition, the electrical connecting terminals may be surface-mounted on the coil assembly printed circuit board 130 and then reflow soldered.

Additionally, in the present embodiment, the main PCB 110 and the coil assembly PCB 130 are electrically interconnected by a PCB inter-connector, for example a pin PCB connector.

In such a configuration, the inductive charging antenna coil assembly 120 is directly electrically and mechanically connected to the coil assembly printed circuit board 130. The electrical connection between the inductive charging antenna coil assembly 120 and the main PCB 110 is achieved indirectly through the electrical connection between the coil assembly printed circuit board 130 and the main PCB 110. Such an assembly facilitates automatic production and assembly: the two PCBAs can be assemble separately as sub-assembly and connected later on the product assembly line.

Preferably, the coil assembly printed circuit board 130 is a printed circuit board that is at least single layered but, in most of the practical cases it will be of 2, 4 or even more layers. The coil assembly printed circuit board 130 has a preferably thin thickness. In the present application, thanks to the direct attachment of the inductive charging antenna coil assembly 120 to the coil assembly printed circuit board 130, it is possible to minimize the gap between the charging surface of a device to be charged and the inductive charging antenna coil 150, thereby improving the inductive charging coupling factor and consequently its efficiency.

Preferably, the coil assembly printed circuit board 130 has a mostly rectangular shape and a surface area thereof is set in such a way that the coil assembly printed circuit board 130 is capable of carrying the entire inductive charging antenna coil assembly 120. The surface area of the coil assembly printed circuit board 130 is large enough to cover the entire inductive charging antenna coil assembly 120 so as to have a shielding function as described above with respect to the entire inductive charging antenna coil assembly 120, as shown in Figure 2 which shows a partial cross-sectional view of the assembled inductive charging antenna structure according to the present embodiment.

In the present application, since the size of the coil assembly printed circuit board 130 may cover the entire inductive charging antenna coil assembly, the size of the main PCBA can be reduced to the minimum needed to to layout the electrical components controlling the operation of the inductive charging on the main PCBA.

In the present embodiments, the coil assembly printed circuit board 130 is a rigid printed circuit board. In other embodiments, the coil assembly printed circuit board 130 may be a flexible printed circuit board. In the present embodiment, the inductive charging antenna structure 100 further includes a magnetic insulation sheet 140. The magnetic insulation sheet 140 is located between the inductive charging antenna coil assembly 150 and the main PCB 110. For example, the magnetic insulation sheet 140 may be attached on a face of the PCB A opposite to the coil 150. Glue or double side adhesive liners may be used. Alternatively, a shielding plate may be used the carry the magnetic insulation sheet.

The magnetic insulation sheet 140 may be made of ferrite, and the magnetic insulation sheet 140 may be rigid or flexible. Most current emitter applications use a rigid ferrite plate (which is about 2 mm thick and thus rigid) as a magnetic shield component. In order to reduce the thickness and the weight of the inductive charging antenna structure 100, thereby reducing the space and cost required, the thickness of the magnetic insulation sheet 140 may be reduced to become flexible. However, it should be noted that the performance of the magnetic insulation sheet 140 might decrease with the thickness. Here, the thickness of the magnetic insulation sheet 140 is preferably less than 0.5 mm, and is preferably 0.2 mm, 0.3 mm or 0.5 mm.

In addition, as shown in Figure 1, the inductive charging antenna structure 100 may further include a temperature sensing el ement 170 for measuring the temperature of the inductive charging antenna coil assembly 120. The temperature sensing element 170 may be a negative temperature coefficient (NTC) element. Each temperature sensing element 170 is electrically connected (preferably, surface-mounted) to the main PCB 110 and placed near the center of the respective coil 150, for example, in a central aperture 151 in the coil 150. In one embodiment, the temperature sensing element 170 is populated on the PCB 110 through a hole (or notch) 141 in the magnetic insulation sheet 140.

In one embodiment not shown, the temperature sensing element 170 may be directly populated on the coil assembly printed circuit board 130.

In the present embodiments, the coil assembly printed circuit board 130 may include a re- radiation pattern laid out on the coil assembly printed circuit board. The re-radiation pattern is designed to attenuate an electric field radiation while allowing a magnetic field to pass through the coil assembly printed circuit board 130.

The re-radiation pattern attenuates an electric field radiation, thereby shielding the electromagnetic radiations and protecting human health.

For example, the coil assembly printed circuit board 130 may be grounded. More specifically, the re -radiation pattern of the coil assembly printed circuit board 130 may be grounded. In the present application, the provision of the re-radiation pattern in the coil assembly printed circuit board 130 allows to eliminate the need for a separated shielding plate. Thus, the manufacturing cost and the thickness of the inductive charging antenna structure 100 are reduced, and the volume of the inductive charging antenna structure 100 is reduced. Moreover, since the need to provide a separated shielding plate is eliminated, the step of connecting the shielding plate to other components is eliminated. Thus, the configuration according to the embodiments of the present disclosure makes it possible to simplify the assembly of the inductive charging antenna structure.

The disclosure is not limited to such an inductive charging antenna structure. In other embodiments, the inductive charging antenna structure may also include a shielding plate (not shown) to further enhance the shielding of the main PCB 110 from the inductive coil radiations. As an example, the shielding plate may be located between the magnetic insulation sheet 140 and the main PCB 110. Additionally or alternatively, the shielding plate may reduce the interference between the coils 150 and the electrical components populated on the main PCB 110.

In the simplest embodiment, the coil assembly printed circuit board 130 has a single layer, the one needed to connect the inductive charging coil assembly 120. It is to be noted that in this case, the coil assembly printed circuit board 130 may be a printed circuit board without a field re-radiation pattern shielding function. For example, the often needed electrical field shielding function may be carried by a shielding pattern located on an additional component above the coil assembly printed circuit board 130.

In the present embodiments, the coil assembly printed circuit board 130 as the re- radiation antenna printed circuit board includes at least an additional layer used to layout the shielding pattern designed to filter electric field radiations while allowing a magnetic field to go through.

In further embodiments, the coil assembly printed circuit board 130 includes at least one additional layer in addition to the layer(s) that is used to layout the re-radiation shielding pattern. Additional electrical components such as near field communication antennas, Bluetooth antennas, WIFI antennas, long term evolution repeaters, back light elements and the like may be placed on the additional layer or using the existing layers. More complex functions may simply be realized by adding PCB layers.

For example, in at least one embodiment, the coil assembly printed circuit board 130 includes, in order, a first layer, a second layer, a third layer and a fourth layer. The shielding pattern is placed on the first layer as well as Bluetooth and or WIFI antennas. The near field communication antenna is placed on the second and third layers. The inductive coils and components are populated on the top layer, i.e., the fourth layer. The long term evolution repeater may use all four layers.

Figures 4 and 5 show an inductive charging antenna structure 200 according to another embodiment of the present disclosure. The inductive charging antenna structure 200 includes a main PCB 210, an inductive charging antenna coil assembly including an inductive charging antenna coil 220, a coil assembly printed circuit board 230 and a magnetic insulation sheet 240. The main PCB 210, the inductive charging antenna coil 220, the magnetic insulation sheet 240, and the coil assembly printed circuit board 230 are placed substantially in parallel to each other. The inductive charging antenna coil 220 is located between the PCB 210 and the coil assembly printed circuit board 230. The magnetic insulation sheet 240 is placed between the inductive charging antenna coil 220 and the main PCB 210.

For example, the magnetic insulation sheet 240 may be attached to a surface of the main PCB 210 facing the magnetic insulation sheet 240 using an adhesive or otherwise.

The inductive charging antenna coil 220 may be electrically and mechanically connected to the coil assembly printed circuit board 230 and electrically connected to the main PCB 210 through the coil assembly printed circuit board 230.

The coil assembly printed circuit board 230 may be a coil assembly printed circuit board including a re -ration pattern designed to attenuate an electric field radiation while allowing a magnetic field to pass through.

In the present embodiment, the coil assembly printed circuit board 230 may be fitted with a connector 280 at a distance from the main PCB 210 such that the inductive charging antenna coil 220 is suspended at a certain distance over the magnetic insulation sheet 240. For example, the connector 208 may be the PCB inter-connector as described above.

The magnetic insulation sheet 240 reverberates the electromagnetic radiation radiated from the inductive charging antenna coil 220, thereby enhancing the intensity of the radiated magnetic field on a side of the inductive charging antenna coil 220 opposite to a side on which the magnetic insulation sheet 240 is located.

In other embodiments, the charging antenna coil 220 is assembled in contact with the magnetic insulation sheet 240 so that a distance between the two is zero. This may be beneficial to reduce a space occupied by the inductive charging antenna structure 200, but not beneficial to improve the radiation efficiency of the inductive charging antenna structure 200.

In the present embodiment, the charging antenna coil 220 and the magnetic insulation sheet 240 are placed at a distance from each other. The impedance of the charging antenna coil 220 resulting from skin and proximity effect can be expressed as: Z=R+jLw, where R, L, and w represent the resistance, inductance, and resonant frequency of the inductive charging antenna coil 220, respectively.

When the distance between the inductive charging antenna coil 220 and the magnetic insulation sheet 240 increases, the values of the resistance R and the inductance L decreases. The decrease in the resistance R causes the quality factor Q of the inductive charging antenna structure 200 to increase, the decrease in the inductance L causes the quality factor Q of the electrical antenna structure 200 to decrease. Within a certain distance range, the distance between the inductive charging antenna coil 220 and the magnetic insulation sheet 240 has a greater influence on the resistance R than on the inductance L. Therefore, an increase in the distance between the inductive charging antenna coil 220 and the magnetic insulation sheet 240 within the certain range generally results in an increase of the quality factor Q.

Experiments have shown that increasing the distance between the inductive charging antenna coil 220 and the magnetic insulation sheet 240 results in the increase in the quality factor Q of the inductive charging antenna structure 200.

Figure 6 is a diagram showing the variation of the quality factor of the inductive charging antenna structure as a function of the distance d between the charging antenna coil and the magnetic insulation sheet according to an embodiment of the present disclosure. The inductive charging antenna structure includes an inductive charging antenna coil. As can be seen from Figure 6, as the distance d between the inductive charging antenna coil and the magnetic insulation sheet increases from 0 to 3.5 mm or more, the quality factor Q of the inductive charging antenna structure according to this embodiment substantially increases from 51 to 58, namely increases by nearly 15%. The above values is measured at a central portion of the inductive charging antenna coil and at a resonant frequency of 130 kHz. As can be seen from Figure 6, an increase in the distance d between the inductive charging antenna coil and the magnetic insulation sheet results in an increase in the quality factor Q of the inductive charging antenna structure.

In the inductive charging antenna structure 200 according to the embodiment of the present disclosure, a preferred range of the distance between the inductive charging antenna coil 220 and the magnetic insulation sheet 240 is 0.3 to 2.5 mm. Also, the inductive charging antenna coil 220 is preferably driven at a resonant frequency of 85 to 205 kHz. In addition, the inductive charging antenna coil 220 may be a litz wire type coil and may have a resistance R of 50 hiW. The inductive charging antenna coil 220 may also be a flat, stamped coil having a resistance R of 150 to 300 mD, preferably 200 hiW. The flat, stamped coil is stamped from a sheet metal. An inductance L of the inductive charging antenna coil 220 may be 8 to 12 mH. Note that the value of the inductance L is measured on the magnetic insulation sheet 240. The inductive charging antenna coil 220 may also be a flexible circuit type coil, in which an inductive charging antenna coil pattern is printed on a flexible printed circuit board.

In the inductive charging antenna structure 200 according to the embodiment of the present disclosure, a surface area of the magnetic insulation sheet 240 is preferably larger than a surface area of the inductive charging antenna coil 220 to better improve the radiation efficiency of the inductive charging antenna coil 220. Preferably, edges of the magnetic insulation sheet 240 is at a distance of more than 2 mm from respective edges of the antenna coil 220.

The material of the magnetic insulation sheet 240 is preferably a NiZn ferrite.

Figures 7 and 8 show an inductive charging antenna construction 300 according to another embodiment of the present disclosure. The inductive charging antenna structure 300 includes a coil assembly printed circuit board (not shown), a main PCB 310, an inductive charging antenna coil assembly having an inductive charging antenna coil 320, a magnetic insulation sheet 340, and a spacer 380. The inductive charging antenna coil assembly is located between the main PCB 310 and the coil assembly printed circuit board. The inductive charging antenna coil 320 of the inductive charging antenna coil assembly is electrically and mechanically connected to the coil assembly printed circuit board and electrically connected to the main PCB 310 through the coil assembly printed circuit board. Additionally, the inductive charging antenna coil 320 is positioned at a distance away from the magnetic insulation sheet 340. The gap may be in a range of 0.3-2.5 mm.

In Figures 7 and 8, the main PCB 310 is supporting the structure. It can be noted that the structural support may not necessarily be a PCB. It could be supported by any suitable, electrically passive part made of polymer or metal. In this case the main PCB would preferably be located underneath the supporting structure.

The magnetic insulation sheet 340 is placed between the inductive charging antenna coil 320 and the main PCB 310.

Unlike the inductive charging antenna structure 200 shown in Figure 5, the inductive charging antenna structure 300 further includes a spacer 380. The spacer 380 is placed between the magnetic insulation sheet 340 and the charging antenna coil 320. The spacer 380 may be placed between the magnetic insulation sheet 340 and the inductive charging antenna coil 320 in order to support the inductive charging antenna coil 320 at the distance from the magnetic insulation sheet 340. In the present embodiment, the spacer 380 may be placed on the magnetic insulation sheet 340. The spacer 380 is made of a magnetically neutral material, which refers to a material that does not magnetically or electrically interfere with the magnetic components surrounding it. Examples of magnetically neutral materials include plastic polymers, ceramics, and the like. Additionally, the spacer 380 may be solid and may be completely filled between the magnetic insulation sheet 340 and the inductive charging antenna coil 320. The spacer 380 may also be hollow or of a framed structure (e.g., a framed structure having ribs). Additionally, the spacer 380 may be formed of a thermally conductive polymer to enhance heat dissipation of the charging antenna coil 320.

Figures 9 shows an inductive charging antenna construction 400 according to another embodiment of the present disclosure. The inductive charging antenna structure 400 includes a coil assembly printed circuit board (not shown), a main PCB 410, an inductive charging antenna coil assembly having an inductive charging antenna coil 420, a magnetic insulation sheet 440, and an over-molded portion 480. The inductive charging antenna coil assembly is located between the main PCB 410 and the coil assembly printed circuit board. The inductive charging antenna coil 420 of the inductive charging antenna coil assembly is electrical ly and mechanically connected to the coil assembly printed circuit board and electrically connected to the main PCB 410 through the coil assembly printed circuit board. Additionally, the inductive charging antenna coil 420 is positioned at a distance away from the magnetic insulation sheet 440. The distance may be in a range of 0.3-2.5 mm.

In Figure 9, the main PCB 410 is supporting the structure. It can be noted that the structural support may not necessarily be a PCB. It could be supported by any suitable, electrically passive part made of polymer or metal. In this case the main PCB would preferably be located underneath the supporting structure.

Unlike the inductive charging antenna structure 200 shown in Figure 5, the inductive charging antenna structure 400 further includes an over-molded portion 480. The inductive charging antenna coil 420 is at least partially over-molded into the over-molded portion 480. That is, the inductive charging antenna coil 420 is at least partially surrounded by the over- molded portion 480. At least a part of the over-molded portion 480 is located between the charging antenna coil 420 and the magnetic insulation sheet 440 in order to support the inductive charging antenna coil 420 at the distance from the magnetic insulation sheet 440.

The over-molded portion 480 prevents the charging antenna coil 420 from being damaged and facilitates the assembly of the inductive charging antenna coil 420. The over molded portion 480 may be solid or hollow or of a framed structure. At least one embodiment of the present disclosure is used in a wireless charging module. The wireless charging module may include any of the inductive charging antenna structure 100, 200, 300, 400 as described above and include an electrical connector, such as the electrical connector 160 as shown in Figures 1-3, for connection to a motor vehicle electrical system. Preferably, the electrical connector is placed on a side of the PCB of the inductive charging antenna structure on which the electrical components are populated or beneath the PCB. That is, the electrical connector and the el ectrical components are populated on the same side of the PCB, opposite to the side facing the inductive charging antenna coil assembly. Using such a configuration, it is possible to minimize an overall thickness of the wireless charging module.

Different wireless charging principles result in different configurations of the inductive charging antenna structure. Therefore, the configuration of the inductive charging antenna structure is not limited to the configuration of the inductive charging antenna structure according to the embodiments of the present disclosure described above. In addition, the inductive charging antenna structure of the present disclosure may be designed according to the QI standard of the Wireless Power Consortium (WPC), or may be designed according to other standards.

At least one embodiments of the present disclosure is used in a motor vehicle. The motor vehicle may be integrated with the wireless charging module as described above.

There are a few points to note:

(1) The drawings of the embodiments of the present disclosure relate only to the structures involved in the embodiments of the present disclosure, and other structures can be referred to the general design.

(2) In the case of no conflict, the embodiments of the present disclosure and the features in the embodiments can be combined with each other to obtain a new embodiment.

The foregoing are merely exemplary embodiments of the disclosure, but are not used to limit the protection scope of the disclosure. The protection scope of the disclosure shall be defined by the attached claims.

Claims

CLAIMS What is claimed is:

1. An inductive charging antenna structure, including:

a main printed circuit board populated with electrical components that control an inductive charging process;

an inductive charging antenna coil assembly including at least one coil;

a magnetic insulation sheet located between the main printed PCB and the inductive charging antenna coil assembly; and

a coil assembly printed circuit board, wherein

the inductive charging antenna coil assembly is located between the printed circuit board and the coil assembly printed circuit board, and

the at least one coil of the inductive charging antenna coil assembly is electrically and mechanically connected to the coil assembly printed circuit board, and is further electrically connected to the main printed circuit board.

2. The inductive charging antenna structure according to claim 1, wherein

the at least one coil of the inductive charging antenna coil assembly is electrically connected to the main printed circuit board through the coil assembly printed circuit board.

3. The inductive charging antenna structure according to claim 1, wherein

a surface area of coil assembly printed circuit board is set in such a way that the coil assembly printed circuit board is capable of carrying the entire inductive charging antenna coil assembly.

4. The inductive charging antenna structure according to claim 3, wherein

the at least one coil is suspended at the distance away from the magnetic insulation sheet by the coil assembly printed circuit board.

5. The inductive charging antenna structure according to claim 1, further comprising: a spacer, wherein the spacer is placed between the magnetic insulation sheet and the at least one coil to support the at least one coil over the magnetic insulation sheet.

6. The inductive charging antenna structure according to claim 1, further comprising: an over-molded portion at least partially over-molding the at least one coil, wherein at least a portion of the over-molded portion is located between the at least one coil and the magnetic insulation sheet to support the at least one coil over the magnetic insulation sheet.

7. The inductive charging antenna structure according to claim 3 to 6, wherein the at least one coil is placed at a distance ranging from 0.3 to 2.5mm to the magnetic insulation sheet.

8. The inductive charging antenna structure according to claim 1 to 7, wherein the magnetic insulation sheet is a rigid or flexible type ferrite sheet.

9. The inductive charging antenna structure according to claim 1, further including:

at least one temperature sensing element, wherein each temperature sensing element is surface-assembled on a side of the coil assembly printed circuit board where the inductive charging antenna coil assembly is located or on a side of the main printed circuit board facing the inductive charging antenna coil assembly.

10. The inductive charging antenna structure according to claim 1, wherein the coil assembly printed circuit board includes a re-radiation pattern laid out on at least one layer of the coil assembly printed circuit board, designed to a filter electric field radiation while allowing a magnetic field to go through.

11. The inductive charging antenna structure according to claim 1, wherein the coil assembly printed circuit board includes on one or more layers for a near field communication antenna, a Bluetooth antenna, a WIFI antenna, a long term evolution repeater.

12. The inductive charging antenna structure according to claim 1, wherein the coil assembly printed circuit board is populated with components to control a near field communication antenna, a Bluetooth antenna, a WIFI antenna, a long term evolution repeater, or to realize a backlight function.

13. The inductive charging antenna structure according to claim 1, wherein

the at least one coil of the inductive charging antenna coil assembly is electrically and mechanically connected to the coil assembly printed circuit board by welding or via an interconnecting part of the at least one coil to a mating interconnecting part of the coil assembly printed circuit board.

14. A wireless charging module including the inductive charging antenna structure according to any one of the claims 1 to 13.

15. The wireless charging module according to claim 14, further comprising an electrical connector for connecting the wireless charging module to a motor vehicle electrical system.

16. A motor vehicle including the wireless charging module according to any one of the claims 14 to 15.