Wireless charger and charging system with multi-compatibility

A wireless charger and charging system compatible with several wireless charging solutions is provided. The wireless charger includes a charging module having a transmitting member that transfers wireless power to a receiving member of a chargeable device so that a battery of the chargeable device can be charged. If the chargeable device is compliant with a recognized wireless charging solution, a charging session can be initiated and the charging module can charge the chargeable device using a charging protocol that is compatible with the wireless charging solution.

FIELD OF THE INVENTION

The present invention generally relates to a wireless charger and more specifically to a wireless charger that is compatible for use with a variety of wireless charging solutions.

BACKGROUND OF THE INVENTION

Wireless chargers are gaining in popularity and there currently exists a variety of wireless charging solutions to choose from. Typically, differing wireless charging solutions are incompatible with one another. For instance, two of the most popular wireless charging solutions feature Qi® and Powermat® charging technology. Unfortunately, Qi® compliant devices are unable to be charged by wireless chargers employing Powermat® charging technology, and vice versa. As such, users may be forced to rely on a single wireless charging solution or mix and match several wireless charging solutions to ensure their charging needs are met. Therefore, there is a need for a wireless charger that is multi-compatible with popular wireless charging solutions.

SUMMARY OF THE INVENTION

According to one aspect of the present invention, a wireless charger for a chargeable device is provided, wherein the chargeable device is compliant with a specific wireless charging solution and has a receiving member configured to receive wireless power. The wireless charger includes a charging module having a transmitting member configured to transfer wireless power to the receiving member according to a charging protocol that is selected from a plurality of charging protocols, the charging protocol being compatible with the specific wireless charging solution.

According to another aspect of the present invention, a wireless charging system of a vehicle is provided and is usable with a chargeable device that is compliant with a specific wireless charging solution. The wireless charging system includes a charging module configured to wirelessly charge the chargeable device according to a charging protocol that is selected from a plurality of charging protocols, the charging protocol being compatible with the specific wireless charging solution. The wireless charging system also includes a main module that is separated from the charging module and is configured to control the charging module.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

To promote an understanding of the present invention, the embodiments described herein are referenced in a vehicular setting for purposes of illustration. However, it is to be understood that the present invention is adaptable to a variety of settings and is not limited for use in vehicles only.

Referring now toFIG. 1, a charging module10is generally shown flushly mounted to a surface12in a vehicle interior13. Preferably, the surface12is easily accessible and does not encumber the use of other features in the vehicle. One suitable surface12includes the center console area of the vehicle. To mount the charging module10to the surface12, the charging module10may include a plurality of screw tabs14that are fastened to the underside of the surface12.

The charging module10includes a body16that is preferably plastic and that defines an interior space18and a charging surface20. The charging surface20is preferably a monochromatic Class A surface type and directly supports a chargeable device22such as a cellular phone or other portable electronic device that is compatible with the charging module10. In the present embodiment, internal components are arranged in the interior space18in a tiered assembly19. The first tier defines a transmitting member24configured to wirelessly transfer power to a receiving member26that is conventionally coupled to the chargeable device22for charging the battery of the chargeable device22. The second tier defines a shielding member28, such as a ferrite, to minimize the effects of the electromagnetic field (EMF) generated during wireless power transfer. The third tier defines a heat sink30that minimizes power dissipation and is preferably constructed from aluminum or copper. The fourth tier defines a printed circuit board31(herein referred to as PCB) that is configured to energize the transmitting member24to wirelessly charge the chargeable device22. The PCB31is supplied power from a vehicle power source (not shown) and may be electrically coupled to the vehicle power source using a conventional vehicle wire harness33. To support the tiered assembly19, one or more support spacers34may be provided in the interior space18and disposed between the PCB31and a bottom surface35of the body16.

Generally, the transmitting member24and receiving member26must be accurately aligned for optimum wireless charging to occur. This is particularly evident with respect to commonly used wireless charging solutions employing either Qi® or Powermat® charging technology, each offering a unique charging protocol for charging a variety of compliant devices fitted with their respective receiving members26. Therefore, one challenge in providing a wireless charger with multi-compatibility is facilitating efficient wireless power transfer between the transmitting member24and the receiving member26given the likelihood that the position of the receiving member26and/or charging protocol will vary depending on the device itself and/or the adopted wireless charging solution.

To address this challenge, one embodiment of the charging module10is generally shown inFIG. 2, and is configured to charge a chargeable device22based on the principles of wireless induction. In this embodiment, the transmitting member24includes one or more transmitting coils36configured to inductively transfer power to the receiving member26of a Qi® or Powermat® compliant device, which typically includes a receiving coil (not shown). As previously noted, the location of the receiving member26for any particular chargeable device22may not always be readily determined, which may hinder the ability to accurately align the transmitting member24and receiving member26. To account for this, three transmitting coils36, preferably having Litz wire windings, are arrayed in the present embodiment and configured to substantially coincide with the charging surface20to enable accurate alignment of at least one of the transmitting coils36with the receiving coil so that a charging session can be initiated.

To prevent the chargeable device22from moving and potentially causing the receiving coil to lose alignment with the transmitting coil(s)36, a bumper assembly38or other suitable holding assembly may be employed, as shown inFIGS. 3 and 4. The bumper assembly38includes a first bumper38adisposed opposite to a second bumper38b, wherein each bumper38a,38bis configured to move in concert away from the center of the charging surface20to allow the chargeable device22to be inserted between each bumper38a,38b. Additionally, the bumpers38a,38bmay be spring loaded with a bias favoring the return of each bumper38a,38btowards the center of the charging surface20. In this manner, the bumper assembly38provides the necessary holding force to removably secure chargeable devices22of various widths to the charging surface20so that inductive charging can occur without interruption.

Referring now toFIGS. 5 and 6, two schematic diagrams of a charging system39for use inside a vehicle are generally shown, wherein each charging system39is configured to wirelessly charge Qi® and Powermat® compliant devices and includes the charging module10of the previous embodiments.

As shown in each schematic diagram, the charging system39includes a first controller40and a second controller42that are each a part of the charging module10. The first and second controllers40,42are connected to the transmitting coils36and supplied by a power circuit44. The first controller40is configured to trigger wireless charging based on the Qi® charging protocol and the second controller42is configured to trigger wireless charging based on the Powermat® charging protocol. It should be understood that the first and second controllers40,42are configured to operate exclusively, such that when one is on, the other is off. Also, it should be noted that the Qi® and Powermat® charging protocols have different operating voltages. Typically, the Qi® charging protocol has a voltage requirement of approximately 19 volts DC whereas the Powermat® charging protocol has a voltage requirement of approximately 18 volts DC. To supply the first and second controllers40,42with the required voltage, the power circuit44is connected to the vehicle power source, which typically provides 12 volts DC. The power circuit44includes a DC-DC converter45to convert the supplied voltage from 12 volts DC to 19 volts DC, thereby satisfying the voltage requirement of the first controller40. To satisfy the voltage requirement of the second controller42, a diode46may be added in series to the power circuit44to produce a voltage drop from 19 volts DC to 18 volts DC. As should be obvious to those skilled in the art, other circuit configurations may be employed to achieve the different voltage potentials.

Optionally, the charging system39may include one or more status indicators48configured to provide charging information to a vehicle occupant and may be provided on any viewable surface of the charging module10. For example, a first and second status indicator48a,48bassociated with the first and second charging protocols may be used to notify the vehicle occupant as to which charging protocol is in use. Also, the charging system39may include a third status indicator48cused to inform the vehicle occupant as to the current charge state of the chargeable device22. Preferably, each status indicator48is visually differentiated from the other so that the occupant can readily discern the type of information being provided. For example, a suitable first and second status indicator48a,48bmay include a differently colored light and/or an illuminated logo for each associated charging protocol and a suitable third status indicator48cmay include an illuminated battery icon displaying a charge percentage and/or distribution.

The charging system39may also optionally include a USB port49to enable an occupant to forego wireless charging in favor of conventionally wire charging a chargeable device22by plugging it into the USB port49. With the inclusion of the USB port49, it is conceivable to simultaneously charge at least two chargeable devices22, wherein one is charged using the USB port49and the other is charged using the charging module10. It should further be appreciated that other wired charging connections may be employed.

Further included in the charging system39is a microcontroller50or other suitable processing unit that is configured to communicate with other charging system39components, such as the first and second controllers40,42via a local interconnect network (LIN)51and communicates with the vehicle network via a controller area network (CAN) bus52. As such, the added benefit of network connectivity opens the door to a variety of useful features that incorporate the charging system39with preexisting vehicle systems. For example, in instances where the vehicle battery becomes severely low, an active charging session may be selectively disabled to allow the vehicle battery to better support other vehicle systems. In another example, an interactive vehicle system such as the front center display and/or audio system, may be used to provide useful charging information such as the state of charge for a given chargeable device22or notify an occupant if an incompatible device is detected. In yet another example, the interactive vehicle system may also be used to notify an occupant if inadvertent dual charging is detected, which typically occurs when a chargeable device22being charged via the USB port49is also placed on the charging surface20to induce wireless charging and may potentially damage the chargeable device22and/or the charging system39. While these are just a few instances benefiting from network connectivity, it should be obvious to those skilled in the art that many more useful applications are possible.

As shown inFIG. 5, the power circuit44and microcontroller50are both provided in the charging module10. In this configuration, the charging module10may function as a standalone unit replete with built-in charging system39and requires only an external power source. As previously described, the charging module10may be integrated to the surface12of the vehicle using the screw tabs14or other suitable mounting assembly.

An alternative configuration is shown inFIG. 6, wherein the power circuit44and microcontroller48are provided in a main module54that is separate from the charging module10and may be integrated with any suitable vehicle structure and/or system. In this configuration, the charging module10functions as a satellite unit under the control of the main module54, which initiates charge sessions and supplies the charging module10with power as a result of the inclusion of the power circuit44and microcontroller50. Due to the absence of the power circuit44from the charging module10, downsizing opportunities arise since the power circuit44and accompanying DC-DC converter45typically consume a large space relative to other charging system components. As a result, the charging module10may take on a smaller profile making it more easily accommodated in premium areas such as the center console, arm rests, and/or seatbacks of the vehicle. As previously described, the components in the main module54and charging module10benefit from network connectivity and it is therefore conceivable that additional charging modules10may be networked with the main module54to provide occupants with additional charging opportunities in a greater number of areas inside the vehicle.

In each configuration, the microcontroller50is tasked with initiating a charging session when a chargeable device22is detected on the charging surface20of the charging module10. The chargeable device22may be detected using any of several known methods such as capacitive sensing, infrared camera, Bluetooth®, break beam sensor, and/or pressure switch. At the onset of the charging session, the microcontroller50first determines whether the chargeable device22is Qi® or Powermat® compliant. To do so, the microcontroller50begins an inductive query by pinging a receiver (not shown) of the chargeable device22with the last active charging protocol to gauge compatibility. Typically the receiver is specific to the particular charging protocol and comes prepackaged with the corresponding receiving member26and associated charging circuit, all of which are typically integrated with the chargeable device22or provided in a chargeable device22holder. If compatible, a handshake occurs between the microcontroller50and the receiver whereby the receiver indicates its presence by communicating received signal strength and control data to the microcontroller50. If incompatible, then no handshake occurs between the microcontroller and receiver26, which prompts the microcontroller50to switch to the next charging protocol in queue and start another inductive query. In this manner, it is conceivable to employ a plurality of selected charging protocols and loop through them in the above-described manner until the desired handshake occurs. If no compatible receiver is found at the completion of the inductive query, then the occupant may be notified that an incompatible device has been detected.

With respect to the charging system39ofFIGS. 5 and 6, the last active charging protocol is either the Qi® protocol or the Powermat® protocol and is typically saved to a memory location of the microcontroller44. In the event no last active charging protocol is available, one of the Qi® and the Powermat® charging protocols may be assigned as the default charging protocol for purposes of starting the inductive query.

Once the necessary charging protocol is determined, the wireless charging process may begin once at least one transmitting coil36is identified to be in accurate alignment with the receiving coil. At present, the Qi® charging protocol is operable using one or more transmitting coils36while the Powermat® charging protocol is relegated for use with a single transmitting coil36. Thus, when charging a Powermat® compliant device, steps must be taken to determine which transmitting coil36is most accurately aligned with the receiving coil and then signaling the second controller42to trigger the Powermat® charging protocol using only the selected transmitting coil36to most effectively transfer wireless power to the receiving coil. One possible method includes configuring the microcontroller50to selectively connect each transmitting coil36to the power circuit44one at a time and selecting the transmitting coil36having the highest load power value, and therefore most accurate alignment, to charge the receiving coil while keeping the rest disconnected from the power circuit44. Such a method is described in U.S. Pat. No. 8,120,316 B2 entitled “WIRELESS CHARGING SYSTEM” and filed on Aug. 13, 2009 by Kim-Yeung Sip, the entire disclosure of which is incorporated herein by reference.

For charging a Qi® compliant device, the microcontroller50may also select a transmitting coil36pursuant to the method outlined for the Powermat® charging protocol and subsequently signal the first controller40to trigger the Qi® charging protocol. Concerning Qi® compliant devices, if more versatility is desired, it is conceivable to configure the microcontroller50to select more than one transmitting coil36to more efficiently charge a Qi® compliant device in instances where the receiving coil is at least partially aligned with more than one transmitting coil36. For example, if the two highest load powers identified are substantially similar, the microcontroller50may opt to use both of the corresponding transmitting coils36to charge the Qi® compliant device as opposed to selecting the transmitting coil36having the single highest load power.

Upon completion of the selected charging protocol or the premature removal of a chargeable device by an occupant, the microcontroller50saves the selected charging protocol to memory to serve as the last active charging protocol for the next charging session.

Accordingly, a wireless charger with multi-compatibility has been advantageously provided herein. The wireless charger is able to efficiently charge chargeable devices configured for different charging protocols such as Qi® and Powermat® compliant devices and may be particularly adapted for use in a vehicle and configured to communicate over the vehicle network.