# Patent

## Title
Wireless power transmitter

## Abstract

A wireless power transmitter includes a body having a coil module therein, and configured to transmit power in a wireless manner, a blowing module configured to cool the coil module by moving a fluid by convection and a guide module extending from the blowing module to outside of the body such that the fluid from the blowing module is discharged to outside of the body after cooling the coil module. The coil module has a shape corresponding to an outer circumference of the coil module partially or wholly.

## Background
CROSS-REFERENCE TO RELATED APPLICATION
Pursuant to 35 U.S.C. §119(a), this application claims the benefit of earlier filing date and right of priority to Korean Application No. 10-2013-0002232, filed on Jan. 8, 2013 the contents of which is incorporated by reference herein in its entirety.
BACKGROUND OF THE DISCLOSURE
1. Field of the Disclosure
The present disclosure relates to a wireless power transmitter, and particularly, to a wireless power transmitter capable of charging an electronic device in a wireless manner.
2. Description of Related Art
As functions of a mobile terminal become more diversified, the mobile terminal can support more complicated functions such as capturing images or video, reproducing music or video files, playing games, receiving broadcast signals, and the like. By comprehensively and collectively implementing such functions, the mobile terminal may be embodied in the form of a multimedia player or a device.
Terminals can be divided into mobile/portable terminals and stationary terminals according to their mobility. The mobile terminal is a portable device that can be carried anywhere and have one or more of a function of performing voice and video calls, a function of inputting/outputting information, a function of storing data, etc.
In order to support and enhance such functions of the terminal, it can be considered to improve configuration and/or software of the terminal.
In recent years, a mobile terminal which can be wirelessly charged, without an adapter configured to connect an external power to the mobile terminal for charging of a battery, is being developed.
A wireless power transmitter, configured to wirelessly charge the mobile terminal, is also being developed. In order to effectively reduce heat emission from inside of the wireless power transmitter, a new structure of the wireless power transmitter may be considered.
SUMMARY OF THE DISCLOSURE
Therefore, an aspect of the detailed description is to provide a wireless power transmitter having an enhanced structure, and capable of cooling inside of a body in a more efficient manner.
To achieve these and other advantages and in accordance with the purpose of this specification, as embodied and broadly described herein, there is provided a wireless power transmitter, comprising: a body having a coil module therein, and configured to transmit power in a wireless manner; a blowing module configured to cool the coil module by moving a fluid by convection; and a guide module extending from the blowing module to outside of the body such that the fluid from the blowing module is discharged to outside of the body after cooling the coil module, and having a shape corresponding to an outer circumference of the coil module partially or wholly.
In an embodiment of the present invention, the wireless power transmitter may further comprise a front case and a rear case which form appearance of the body, and the guide module may be formed on an inner surface of the front case.
In an embodiment of the present invention, the coil module may comprise: a fixing plate fixed to the rear case; and a coil disposed on the fixing plate.
In an embodiment of the present invention, the front case may comprise protrusions configured to make an electronic device for receiving wireless power spaced from an outer surface of the front case when the electronic device is mounted on the outer surface of the front case.
In an embodiment of the present invention, the front case may further comprise an outer guide configured to guide the fluid discharged from the blowing module to be discharged to a space between the electronic device and the outer surface of the front case through an opening of the front case.
In an embodiment of the present invention, the wireless power transmitter may further comprise a circuit board having devices for supplying wireless power signals to the coil module.
In an embodiment of the present invention, the guide module may comprise: a coil cooling portion configured to cool the coil module; and a circuit board cooling portion configured to cool the circuit board.
In an embodiment of the present invention, the coil cooling portion may be formed in a ring shape to enclose an outer circumference of the coil of the coil module. One side of the coil cooling portion may be communicated with the blowing module, and another side thereof may be communicated with the circuit board cooling portion.
In an embodiment of the present invention, the circuit board cooling portion may comprise a pair of ribs protruding from an inner surface of the body.
In an embodiment of the present invention, the wireless power transmitter may further comprise a pad disposed between the circuit board and the circuit board cooling portion such that heat generated from the circuit board is transferred to the circuit board cooling portion.
In an embodiment of the present invention, at least part of the pad may be disposed between the ribs.
In an embodiment of the present invention, the blowing module may comprise: a housing; and a diaphragm configured to move up and down in the housing when supplied with a voltage.
In an embodiment of the present invention, the blowing module may be formed to be rotatable at a prescribed angle with respect to the guide module, so as to blow the fluid.
According to another aspect of the present invention, there is provided a wireless power transmitter, comprising: a coil module mounted in a body, and configured to wirelessly charge an electronic device disposed close thereto; a case which forms appearance of the body; a guide module formed to enclose the coil module, and having an opening penetratingly-formed at the case; and a blowing module communicated with the guide module such that heat generated from the coil module is discharged to outside of the body through the opening.
In an embodiment of the present invention, part of the guide module enclosing the coil module may have a ring shape.
In an embodiment of the present invention, the wireless power transmitter may further comprise a circuit board having devices for supplying wireless power signals to the coil module.
In an embodiment of the present invention, the guide module may comprise: a coil cooling portion configured to cool the coil module; and a circuit board cooling portion configured to cool the circuit board.
In an embodiment of the present invention, one side of the coil cooling portion may be communicated with the blowing module, and another side thereof may be communicated with the circuit board cooling portion.
In an embodiment of the present invention, the circuit board cooling portion may comprise a pair of ribs protruding from an inner surface of the body.
In an embodiment of the present invention, the wireless power transmitter may further comprise a pad disposed between the circuit board and the circuit board cooling portion such that heat generated from the circuit board is transferred to the circuit board cooling portion.
In an embodiment of the present invention, part of the coil cooling portion contacting the coil module may have higher thermal conductivity than other parts.
In an embodiment of the present invention, the guide module and the case may be integrally formed with each other.
According to the present invention, when an electronic device is charged, heat generated from the body of the wireless power transmitter can be controlled more effectively, under a novel structure of the blowing module mounted in the body, and the guide module for cooling the circuit board.
Further scope of applicability of the present application will become more apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the disclosure, are given by way of illustration only, since various changes and modifications within the spirit and scope of the disclosure will become apparent to those skilled in the art from the detailed description.



BRIEF DESCRIPTION OF THE DRAWINGS
The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments and together with the description serve to explain the principles of the disclosure. In the drawings:
FIG. 1 is an exemplary view illustrating a wireless power transmitter and an electronic device according to preferred embodiments of the present invention;
FIGS. 2A and 2B are block diagrams illustrating a configuration of a wireless power transmitter 100 and an electronic device 200 according to preferred embodiments of the present invention;
FIG. 3 is a conceptual view illustrating that power is wirelessly transmitted from a wireless power transmitter to an electronic device by an inductive coupling method;
FIGS. 4A and 4B are a block diagram illustrating a configuration of a wireless power transmitter 100 and an electronic device 200 by an electromagnetic induction method which can be applied to preferred embodiments of the present invention;
FIG. 5 is a block diagram of a wireless power transmitter having one or more transmitting coils for receiving power by an inductive coupling method which can be applied to embodiments of the present invention;
FIG. 6 is a conceptual view illustrating that power is wirelessly transmitted from a wireless power transmitter to an electronic device by a resonance coupling method;
FIGS. 7A and 7B are a block diagram illustrating a configuration of a wireless power transmitter 100 and an electronic device 200 by a resonance method which can be applied to preferred embodiments of the present invention;
FIG. 8 is a block diagram of a wireless power transmitter having one or more transmitting coils for receiving power by a resonance coupling method which can be applied to embodiments of the present invention;
FIG. 9 is a block diagram of a wireless power transmitter having an additional configuration as well as a configuration of FIG. 2A;
FIG. 10 is a view illustrating a case where an electronic device 200 according to embodiments of the present invention is implemented as a mobile terminal;
FIG. 11 is a front perspective view of a wireless power transmitter according to an embodiment of the present invention;
FIG. 12 is an exploded perspective view of FIG. 11;
FIGS. 13A and 13B are perspective views of a front case of FIG. 11;
FIG. 14 is a sectional view taken along line ‘IV-IV’ in FIG. 11;
FIG. 15 is a conceptual view illustrating a coupled state of a pad to a front case of FIG. 13;
FIG. 16 is a modification embodiment of a wireless power transmitter, which illustrates an example of a blowing module configured to be rotatable; and
FIG. 17 is another modification embodiment of a wireless power transmitter, which illustrates an example where an outer guide is formed at a front case.



DETAILED DESCRIPTION OF THE DISCLOSURE
Description will now be given in detail of the exemplary embodiments, with reference to the accompanying drawings. For the sake of brief description with reference to the drawings, the same or equivalent components will be provided with the same reference numbers, and description thereof will not be repeated.
The technologies disclosed herein may be applicable to wireless power transfer (contactless power transfer). However, the technologies disclosed herein are not limited to this, and may be also applicable to all kinds of power transmission systems and methods, wireless charging circuits and methods to which the technological spirit of the technology can be applicable, in addition to the methods and apparatuses using power transmitted in a wireless manner.
It should be noted that technological terms used herein are merely used to describe a specific embodiment, but not to limit the present invention. Also, unless particularly defined otherwise, technological terms used herein should be construed as a meaning that is generally understood by those having ordinary skill in the art to which the invention pertains, and should not be construed too broadly or too narrowly. Furthermore, if technological terms used herein are wrong terms unable to correctly express the spirit of the invention, then they should be replaced by technological terms that are properly understood by those skilled in the art. In addition, general terms used in this invention should be construed based on the definition of dictionary, or the context, and should not be construed too broadly or too narrowly.
Incidentally, unless clearly used otherwise, expressions in the singular number include a plural meaning. In this application, the terms “comprising” and “including” should not be construed to necessarily include all of the elements or steps disclosed herein, and should be construed not to include some of the elements or steps thereof, or should be construed to further include additional elements or steps.
In addition, a suffix “module” or “unit” used for constituent elements disclosed in the following description is merely intended for easy description of the specification, and the suffix itself does not give any special meaning or function.
Furthermore, the terms including an ordinal number such as first, second, etc. can be used to describe various elements, but the elements should not be limited by those terms. The terms are used merely for the purpose to distinguish an element from the other element. For example, a first element may be named to a second element, and similarly, a second element may be named to a first element without departing from the scope of right of the invention.
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings, and the same or similar elements are designated with the same numeral references regardless of the numerals in the drawings and their redundant description will be omitted.
In describing the present invention, moreover, the detailed description will be omitted when a specific description for publicly known technologies to which the invention pertains is judged to obscure the gist of the present invention. Also, it should be noted that the accompanying drawings are merely illustrated to easily explain the spirit of the invention, and therefore, they should not be construed to limit the spirit of the invention by the accompanying drawings.
FIG. 1 is an exemplary view conceptually illustrating a wireless power transmitter and an electronic device according to the embodiments of the present invention. Referring to FIG. 1, the wireless power transmitter 100 may be a power transfer apparatus configured to transfer power required for the electronic device (or wireless power receiver) 200 in a wireless manner.
Furthermore, the wireless power transmitter 100 may be a wireless charging apparatus configured to charge a battery of the electronic device (or wireless power receiver) 200 by transferring power in a wireless manner. A case where the wireless power transmitter 100 is a wireless charging apparatus will be described later with reference to FIG. 9.
Additionally, the wireless power transmitter 100 may be implemented with various forms of apparatuses transferring power to the electronic device (or wireless power receiver) 200 requiring power in a contactless state.
The electronic device (or wireless power receiver) 200 is a device that is operable by receiving power from the wireless power transmitter 100 in a wireless manner. Furthermore, the electronic device (or wireless power receiver) 200 may charge a battery using the received wireless power.
On the other hand, an electronic device for receiving power in a wireless manner as described herein should be construed broadly to include a portable phone, a cellular phone, a smart phone, a personal digital assistant (PDA), a portable multimedia player (PMP), a tablet, a multimedia device, or the like, in addition to an input/output device such as a keyboard, a mouse, an audio-visual auxiliary device, and the like.
The electronic device (or wireless power receiver) 200, as described later, may be a mobile communication terminal, (for example, a portable phone, a cellular phone, and a tablet or multimedia device). In case where the electronic device is a mobile terminal, it will be described later with reference to FIG. 10.
On the other hand, the wireless power transmitter 100 may transfer power in a wireless manner without mutual contact to the electronic device (or wireless power receiver) 200 using one or more wireless power transfer methods. In other words, the wireless power transmitter 100 may transfer power using at least one of an inductive coupling method based on magnetic induction phenomenon by the wireless power signal and a magnetic resonance coupling method based on electromagnetic resonance phenomenon by a wireless power signal at a specific frequency.
Wireless power transfer in the inductive coupling method is a technology transferring power in a wireless manner using a primary coil and a secondary coil, and refers to the transmission of power by inducing a current from a coil to another coil through a changing magnetic field by a magnetic induction phenomenon.
Wireless power transfer in the resonance coupling method refers to a technology in which the electronic device (or wireless power receiver) 200 generates resonance by a wireless power signal transmitted from the wireless power transmitter 100 to transfer power from the wireless power transmitter 100 to the wireless power receiver 200 by the resonance phenomenon.
Hereinafter, the wireless power transmitter 100 and electronic device (or wireless power receiver) 200 according to the embodiments disclosed herein will be described in detail. In assigning reference numerals to the constituent elements in each of the following drawings, the same reference numerals will be used for the same constituent elements even though they are shown in a different drawing.
FIGS. 2A and 2B are exemplary block diagrams illustrating the configuration of a wireless power transmitter 100 and an electronic device (or wireless power receiver) 200 that can be employed in the embodiments disclosed herein. Referring to FIG. 2A, the wireless power transmitter 100 may include a power transmission unit 110. The power transmission unit 110 may include a power conversion unit 111 and a power transmission control unit 112.
The power conversion unit 111 transfers power supplied from a transmission side power supply unit 190 to the electronic device (or wireless power receiver) 200 by converting it into a wireless power signal. The wireless power signal transferred by the power conversion unit 111 is generated in the form of a magnetic field or electro-magnetic field having an oscillation characteristic. For this purpose, the power conversion unit 111 may be configured to include a coil for generating the wireless power signal.
The power conversion unit 111 may include a constituent element for generating a different type of wireless power signal according to each power transfer method.
In accordance with exemplary embodiments, the power conversion unit 111 may include a primary coil for forming a changing magnetic field to induce a current to a secondary coil of the electronic device (or wireless power receiver) 200. Furthermore, the power conversion unit 111 may include a coil (or antenna) for forming a magnetic field having a specific resonant frequency to generate a resonant frequency in the electronic device (or wireless power receiver) 200 according to the resonance coupling method.
Furthermore, the power conversion unit 111 may transfer power using at least one of the foregoing inductive coupling method and the resonance coupling method.
Among the constituent elements included in the power conversion unit 111, those for the inductive coupling method will be described later with reference to FIGS. 4A, 4B and 5, and those for the resonance coupling method will be described with reference to FIGS. 7A, 7B and 8.
On the other hand, the power conversion unit 111 may further include a circuit for controlling the characteristics of a used frequency, an applied voltage, an applied current or the like to form the wireless power signal.
The power transmission control unit 112 controls each of the constituent elements included in the power transmission unit 110. The power transmission control unit 112 may be implemented to be integrated into another control unit (not shown) for controlling the wireless power transmitter 100.
On the other hand, a region to which the wireless power signal can be approached may be divided into two types. First, an active area denotes a region through which a wireless power signal transferring power to the electronic device (or wireless power receiver) 200 is passed. Next, a semi-active area denotes an interest region in which the wireless power transmitter 100 can detect the existence of the electronic device (or wireless power receiver) 200. Here, the power transmission control unit 112 may detect whether the electronic device (or wireless power receiver) 200 is placed in the active area or detection area or removed from the area. Specifically, the power transmission control unit 112 may detect whether or not the electronic device (or wireless power receiver) 200 is placed in the active area or detection area using a wireless power signal formed from the power conversion unit 111 or a sensor separately provided therein. For instance, the power transmission control unit 112 may detect the presence of the electronic device (or wireless power receiver) 200 by monitoring whether or not the characteristic of power for forming the wireless power signal is changed by the wireless power signal, which is affected by the electronic device (or wireless power receiver) 200 existing in the detection area. However, the active area and detection area may vary according to the wireless power transfer method such as an inductive coupling method, a resonance coupling method, and the like.
The power transmission control unit 112 may perform the process of identifying the electronic device (or wireless power receiver) 200 or determine whether to start wireless power transfer according to a result of detecting the existence of the electronic device (or wireless power receiver) 200.
Furthermore, the power transmission control unit 112 may determine at least one characteristic of a frequency, a voltage, and a current of the power conversion unit 111 for forming the wireless power signal. The determination of the characteristic may be carried out by a condition at the side of the wireless power transmitter 100 or a condition at the side of the electronic device (or wireless power receiver) 200. In exemplary embodiments, the power transmission control unit 112 may decide the characteristic based on device identification information. In another exemplary embodiment, the power transmission control unit 112 may decide the characteristic based on required power information of the electronic device (or wireless power receiver) 200 or profile information related to the required power. The power transmission control unit 112 may receive a power control message from the electronic device (or wireless power receiver) 200. The power transmission control unit 112 may determine at least one characteristic of a frequency, a voltage and a current of the power conversion unit 111 based on the received power control message, and additionally perform other control operations based on the power control message.
For example, the power transmission control unit 112 may determine at least one characteristic of a frequency, a voltage and a current used to form the wireless power signal according to the power control message including at least one of rectified power amount information, charging state information and identification information in the electronic device (or wireless power receiver) 200.
Furthermore, as another control operation using the power control message, the wireless power transmitter 100 may perform a typical control operation associated with wireless power transfer based on the power control message. For example, the wireless power transmitter 100 may receive information associated with the electronic device (or wireless power receiver) 200 to be auditorily or visually outputted through the power control message, or receive information required for authentication between devices.
In exemplary embodiments, the power transmission control unit 112 may receive the power control message through the wireless power signal. In other exemplary embodiment, the power transmission control unit 112 may receive the power control message through a method for receiving user data.
In order to receive the foregoing power control message, the wireless power transmitter 100 may further include a modulation/demodulation unit 113 electrically connected to the power conversion unit 111. The modulation/demodulation unit 113 may modulate a wireless power signal that has been modulated by the electronic device (or wireless power receiver) 200 and use it to receive the power control message.
In addition, the power transmission control unit 112 may acquire a power control message by receiving user data including a power control message by a communication means (not shown) included in the wireless power transmitter 100.
In accordance with one exemplary embodiment, the wireless power transmitter 100 may supply power to a plurality of electronic devices. Here, collision may occur between wireless power signals which have been modulated by the plurality of electronic devices. Hence, the constituent elements included in the wireless power transmitter 100 may perform various operations to avoid such collision between the modulated wireless power signals.
In one exemplary embodiment, the power conversion unit 111 may convert power supplied from the transmission side power supply unit 190 into a wireless power signal and transfer it to the plurality of electronic devices. For example, the plurality of electronic devices may be two electronic devices, namely, a first electronic device and a second electronic device.
The power conversion unit 111 may generate a wireless power signal for power transmission and receive a first response signal and a second response signal corresponding to the wireless power signal.
The power transmission control unit 112 may determine whether or not the first and second response signals collide with each other. When the first and second response signals collide with each other according to the determination result, the power transmission control unit 112 may reset the power transmission.
The first and second response signals may be generated by modulating the wireless power signal through the first and second electronic devices.
Through the resetting of the power transmission, the power transmission control unit 112 may control the power conversion unit 111 to sequentially receive the first and second response signals, which are generated to avoid collision with each other.
The sequential reception indicates that the first response signal is received after a first time interval and the second response signal is received after a second time interval within a predetermined response period. The first and second time intervals may be decided based on a value obtained by generating a random number.
The predetermined response period (Tping interval) may be decided to be long enough to include both the first response signal and the second response signal. Also, it may be decided after resetting the power transmission.
In accordance with one exemplary embodiment, occurrence or non-occurrence of the collision may be determined according to whether or not the first and second response signals are decoded using a present format. The present format may include a preamble, a header and a message. Whether or not the first and second response signals collide with each other may be determined based on whether or not the first and second response signals are not recoverable due to an error generation in at least one of the preamble, the header and the message caused by the collision.
In accordance with one exemplary embodiment, the power conversion unit 111 may periodically receive a response signal of the first device, which does not collide with a response signal of the second device within a first response period (Tping interval_1). The power transmission control unit may decode the first response signal and the second response signal using a present format, and determine whether or not the first and second response signals have collided with each other based on whether or not the decoding is performed. Here, the first response signal and the second response signal may be periodically received within a second response period (Tping interval_2). The second response period (Tping interval_2) may be decided long enough to include both the first and second response signals, and be decided after resetting the power transmission.
Referring to FIG. 2B, the electronic device (or wireless power receiver) 200 may include a power supply unit 290. The power supply unit 290 supplies power required for the operation of the electronic device (or wireless power receiver) 200. The power supply unit 290 may include a power receiving unit 291 and a power reception control unit (or power receiving control unit) 292.
The power receiving unit 291 receives power transferred from the wireless power transmitter 100 in a wireless manner.
The power receiving unit 291 may include constituent elements required to receive the wireless power signal according to a wireless power transfer method. Furthermore, the power receiving unit 291 may receive power according to at least one wireless power transfer method, and in this case, the power receiving unit 291 may include constituent elements required for each method.
First, the power receiving unit 291 may include a coil for receiving a wireless power signal transferred in the form of a magnetic field or electromagnetic field having a vibration characteristic.
For instance, as a constituent element according to the inductive coupling method, the power receiving unit 291 may include a secondary coil to which a current is induced by a changing magnetic field. In exemplary embodiments, the power receiving unit 291, as a constituent element according to the resonance coupling method, may include a coil and a resonant circuit in which resonance phenomenon is generated by a magnetic field having a specific resonant frequency.
In another exemplary embodiments, when the power receiving unit 291 receives power according to at least one wireless power transfer method, the power receiving unit 291 may be implemented to receive power by using a coil, or implemented to receive power by using a coil formed differently according to each power transfer method.
Among the constituent elements included in the power receiving unit 291, those for the inductive coupling method will be described later with reference to FIGS. 4A and 4B, and those for the resonance coupling method with reference to FIGS. 7A and 7B.
On the other hand, the power receiving unit 291 may further include a rectifier and a regulator to convert the wireless power signal into a direct current. Furthermore, the power receiving unit 291 may further include a circuit for protecting an overvoltage or overcurrent from being generated by the received power signal.
The power reception control unit (or power receiving control unit) 292 may control each constituent element included in the power supply unit 290.
Specifically, the power reception control unit (or power receiving control unit) 292 may transfer a power control message to the wireless power transmitter 100. The power control message may instruct the wireless power transmitter 100 to initiate or terminate a transfer of the wireless power signal. Furthermore, the power control message may instruct the wireless power transmitter 100 to control a characteristic of the wireless power signal.
In exemplary embodiments, the power reception control unit (or power receiving control unit) 292 may transmit the power control message through the wireless power signal. In another exemplary embodiment, the power reception control unit (or power receiving control unit) 292 may transmit the power control message through a method for transmitting user data.
In order to transmit the foregoing power control message, the electronic device (or wireless power receiver) 200 may further include a modulation/demodulation unit 293 electrically connected to the power receiving unit 291. The modulation/demodulation unit 293, similarly to the case of the wireless power transmitter 100, may be used to transmit the power control message through the wireless power signal. The power communications modulation/demodulation unit 293 may be used as a means for controlling a current and/or voltage flowing through the power conversion unit 111 of the wireless power transmitter 100. Hereinafter, a method for allowing the power communications modulation/demodulation unit 113 or 293 at the side of the wireless power transmitter 100 and at the side of the electronic device (or wireless power receiver) 200, respectively, to be used to transmit and receive a power control message through a wireless power signal will be described.
A wireless power signal formed by the power conversion unit 111 is received by the power receiving unit 291. At this time, the power reception control unit (or power receiving control unit) 292 controls the power communications modulation/demodulation unit 293 at the side of the electronic device (or wireless power receiver) 200 to modulate the wireless power signal. For instance, the power reception control unit (or power receiving control unit) 292 may perform a modulation process such that a power amount received from the wireless power signal is varied by changing a reactance of the power communications modulation/demodulation unit 293 connected to the power receiving unit 291. The change of a power amount received from the wireless power signal results in the change of a current and/or voltage of the power conversion unit 111 for forming the wireless power signal. At this time, the modulation/demodulation unit 113 at the side of the wireless power transmitter 100 may detect a change of the current and/or voltage to perform a demodulation process.
In other words, the power reception control unit (or power receiving control unit) 292 may generate a packet including a power control message intended to be transferred to the wireless power transmitter 100 and modulate the wireless power signal to allow the packet to be included therein, and the power transmission control unit 112 may decode the packet based on a result of performing the demodulation process of the power communications modulation/demodulation unit 113 to acquire the power control message included in the packet.
In addition, the power reception control unit (or power receiving control unit) 292 may transmit a power control message to the wireless power transmitter 100 by transmitting user data including the power control message by a communication means (not shown) included in the electronic device (or wireless power receiver) 200.
In addition, the power supply unit 290 may further include a charger (or charging unit) 298 and a battery 299.
The electronic device (or wireless power receiver) 200 receiving power for operation from the power supply unit 290 may be operated by power transferred from the wireless power transmitter 100, or operated by charging the battery 299 using the transferred power and then receiving the charged power. At this time, the power reception control unit (or power receiving control unit) 292 may control the charger (or charging unit) 298 to perform charging using the transferred power.
In one exemplary embodiment, the plurality of electronic devices may receive power from the wireless power transmitter 100. Here, collision may occur between wireless power signals which have been modulated by the plurality of electronic devices. Hence, the constituent elements included in the wireless power transmitter 100 may perform various operations to avoid such collision between the modulated wireless power signals.
In one exemplary embodiment, the power receiving unit 291 may receive the wireless power signal for the power transmission from the wireless power transmitter.
Here, the power reception control unit (or power receiving control unit) 292 may control the power receiving unit 291 to transmit a third response signal corresponding to the wireless power signal after a time interval set to a first time within the first response period (Tping interval_1).
In one exemplary embodiment, the power reception control unit (or power receiving control unit) 292 may determine whether or not the power transmission of the wireless power transmitter 100 has been reset due to collision between the modulated wireless power signal, and set the time interval to a second time when the power transmission has been reset according to the determination result.
In one exemplary embodiment, the power reception control unit (or power receiving control unit) 292 may control the power receiving unit 291 to transmit a fourth response signal corresponding to the wireless power signal after the time interval set to the second time within the second response period (Tping interval_2). The second time may be decided by a value obtained by generating a random number.
Hereinafter, a wireless power transmitter and an electronic device applicable to the embodiments disclosed herein will be described.
First, a method of allowing the wireless power transmitter to transfer power to the electronic device according to the inductive coupling method will be described with reference to FIGS. 3 through 5.
FIG. 3 is a view illustrating a concept in which power is transferred from a wireless power transmitter to an electronic device in a wireless manner according to an inductive coupling method.
When the power of the wireless power transmitter 100 is transferred in an inductive coupling method, if the strength of a current flowing through a primary coil within the power transmission unit 110 is changed, then a magnetic field passing through the primary coil will be changed by the current. The changed magnetic field generates an induced electromotive force at a secondary coil in the electronic device (or wireless power receiver) 200.
According to the foregoing method, the power conversion unit 111 of the wireless power transmitter 100 may include a transmitting (Tx) coil 1111a being operated as a primary coil in magnetic induction. Furthermore, the power receiving unit 291 of the electronic device (or wireless power receiver) 200 may include a receiving (Rx) coil 2911a being operated as a secondary coil in magnetic induction.
First, the wireless power transmitter 100 and electronic device (or wireless power receiver) 200 are disposed in such a manner that the transmitting (Tx) coil 1111a at the side of the wireless power transmitter 100 and the receiving coil at the side of the electronic device (or wireless power receiver) 200 are located adjacent to each other. Then, if the power transmission control unit 112 controls a current of the transmitting (Tx) coil 1111a to be changed, then the power receiving unit 291 controls power to be supplied to the electronic device (or wireless power receiver) 200 using an electromotive force induced to the receiving (Rx) coil 2911a. 
The efficiency of wireless power transfer by the inductive coupling method may be little affected by a frequency characteristic, but affected by an alignment and distance between the wireless power transmitter 100 and the electronic device (or wireless power receiver) 200 including each coil.
On the other hand, in order to perform wireless power transfer in the inductive coupling method, the wireless power transmitter 100 may be configured to include an interface surface (not shown) in the form of a flat surface. One or more electronic devices may be placed at an upper portion of the interface surface, and the transmitting (Tx) coil 1111a may be mounted at a lower portion of the interface surface. In this case, a vertical spacing is formed in a small-scale between the transmitting (Tx) coil 1111a mounted at a lower portion of the interface surface and the receiving (Rx) coil 2911a of the electronic device (or wireless power receiver) 200 placed at an upper portion of the interface surface, and thus a distance between the coils becomes sufficiently small to efficiently implement contactless power transfer by the inductive coupling method.
Furthermore, an alignment indicator (not shown) indicating a location where the electronic device (or wireless power receiver) 200 is to be placed at an upper portion of the interface surface. The alignment indicator indicates a location of the electronic device (or wireless power receiver) 200 where an alignment between the transmitting (Tx) coil 1111a mounted at a lower portion of the interface surface and the receiving (Rx) coil 2911a can be suitably implemented. The alignment indicator may alternatively be simple marks, or may be formed in the form of a protrusion structure for guiding the location of the electronic device (or wireless power receiver) 200. Otherwise, the alignment indicator may be formed in the form of a magnetic body such as a magnet mounted at a lower portion of the interface surface, thereby guiding the coils to be suitably arranged by mutual magnetism to a magnetic body having an opposite polarity mounted within the electronic device (or wireless power receiver) 200.
On the other hand, the wireless power transmitter 100 may be formed to include one or more transmitting coils. The wireless power transmitter 100 may selectively use some of coils suitably arranged with the receiving (Rx) coil 2911a of the electronic device (or wireless power receiver) 200 among the one or more transmitting coils to enhance the power transmission efficiency. The wireless power transmitter 100 including the one or more transmitting coils will be described later with reference to FIG. 5.
Hereinafter, a configuration of the wireless power transmitter and electronic device using an inductive coupling method applicable to the embodiments disclosed herein will be described in detail.
FIGS. 4A and 4B are a block diagram illustrating part of the wireless power transmitter 100 and electronic device (or wireless power receiver) 200 in a magnetic induction method that can be employed in the embodiments disclosed herein. A configuration of the power transmission unit 110 included in the wireless power transmitter 100 will be described with reference to FIG. 4A, and a configuration of the power supply unit 290 included in the electronic device (or wireless power receiver) 200 will be described with reference to FIG. 4B.
Referring to FIG. 4A, the power conversion unit 111 of the wireless power transmitter 100 may include a transmitting (Tx) coil 1111a and an inverter 1112.
The transmitting (Tx) coil 1111a may form a magnetic field corresponding to the wireless power signal according to a change of current as described above. The transmitting (Tx) coil 1111a may alternatively be implemented with a planar spiral type or cylindrical solenoid type.
The inverter 1112 transforms a DC input obtained from the power supply unit 190 into an AC waveform. The AC current transformed by the inverter 1112 drives a resonant circuit including the transmitting (Tx) coil 1111a and a capacitor (not shown) to form a magnetic field in the transmitting (Tx) coil 1111a. 
In addition, the power conversion unit 111 may further include a positioning unit 1114.
The positioning unit 1114 may move or rotate the transmitting (Tx) coil 1111a to enhance the effectiveness of contactless power transfer using the inductive coupling method. As described above, it is because an alignment and distance between the wireless power transmitter 100 and the electronic device (or wireless power receiver) 200 including a primary coil and a secondary coil may affect power transfer using the inductive coupling method. In particular, the positioning unit 1114 may be used when the electronic device (or wireless power receiver) 200 does not exist within an active area of the wireless power transmitter 100.
Accordingly, the positioning unit 1114 may include a drive unit (not shown) for moving the transmitting (Tx) coil 1111a such that a center-to-center distance of the transmitting (Tx) coil 1111a of the wireless power transmitter 100 and the receiving (Rx) coil 2911a of the electronic device (or wireless power receiver) 200 is within a predetermined range, or rotating the transmitting (Tx) coil 1111a such that the centers of the transmitting (Tx) coil 1111a and the receiving (Rx) coil 2911a are overlapped with each other.
For this purpose, the wireless power transmitter 100 may further include a detection unit (not shown) made of a sensor for detecting the location of the electronic device (or wireless power receiver) 200, and the power transmission control unit 112 may control the positioning unit 1114 based on the location information of the electronic device (or wireless power receiver) 200 received from the location detection sensor.
Furthermore, to this end, the power transmission control unit 112 may receive control information on an alignment or distance to the electronic device (or wireless power receiver) 200 through the power communications modulation/demodulation unit 113, and control the positioning unit 1114 based on the received control information on the alignment or distance.
If the power conversion unit 111 is configured to include a plurality of transmitting coils, then the positioning unit 1114 may determine which one of the plurality of transmitting coils is to be used for power transmission. The configuration of the wireless power transmitter 100 including the plurality of transmitting coils will be described later with reference to FIG. 5.
On the other hand, the power conversion unit 111 may further include a power sensing unit 1115. The power sensing unit 1115 at the side of the wireless power transmitter 100 monitors a current or voltage flowing into the transmitting (Tx) coil 1111a. The power sensing unit 1115 is provided to check whether or not the wireless power transmitter 100 is normally operated, and thus the power sensing unit 1115 may detect a voltage or current of the power supplied from the outside, and check whether the detected voltage or current exceeds a threshold value. The power sensing unit 1115, although not shown, may include a resistor for detecting a voltage or current of the power supplied from the outside and a comparator for comparing a voltage value or current value of the detected power with a threshold value to output the comparison result. Based on the check result of the power sensing unit 1115, the power transmission control unit 112 may control a switching unit (not shown) to cut off power applied to the transmitting (Tx) coil 1111a. 
Referring to FIG. 4B, the power supply unit 290 of the electronic device (or wireless power receiver) 200 may include a receiving (Rx) coil 2911a and a rectifier (or rectifying) circuit 2913.
A current is induced into the receiving (Rx) coil 2911a by a change of the magnetic field formed in the transmitting (Tx) coil 1111a. The implementation type of the receiving (Rx) coil 2911a may be a planar spiral type or cylindrical solenoid type similarly to the transmitting (Tx) coil 1111a. 
Furthermore, series and parallel capacitors may be configured to be connected to the receiving (Rx) coil 2911a to enhance the effectiveness of wireless power reception or perform resonant detection.
The receiving (Rx) coil 2911a may be in the form of a single coil or a plurality of coils.
The rectifier (or rectifying) circuit 2913 performs a full-wave rectification to a current to convert alternating current into direct current. The rectifier (or rectifying) circuit 2913, for instance, may be implemented with a full-bridge rectifier generation circuit made of four diodes or a circuit using active components.
In addition, the rectifier (or rectifying) circuit 2913 may further include a regulator circuit for converting a rectified current into a more flat and stable direct current. Furthermore, the output power of the rectifier (or rectifying) circuit 2913 is supplied to each constituent element of the power supply unit 290. Furthermore, the rectifier (or rectifying) circuit 2913 may further include a DC-DC converter for converting output DC power into a suitable voltage to adjust it to the power required for each constituent element (for instance, a circuit such as a charger (or charging unit) 298).
The power communications modulation/demodulation unit 293 may be connected to the power receiving unit 291, and may be configured with a resistive element in which resistance varies with respect to direct current, and may be configured with a capacitive element in which reactance varies with respect to alternating current. The Power reception control unit (or power receiving control unit) 292 may change the resistance or reactance of the power communications modulation/demodulation unit 293 to modulate a wireless power signal received to the power receiving unit 291.
On the other hand, the power supply unit 290 may further include a power sensing unit 2914. The power sensing unit 2914 at the side of the electronic device (or wireless power receiver) 200 monitors a voltage and/or current of the power rectified by the rectifier (or rectifying) circuit 2913, and if the voltage and/or current of the rectified power exceeds a threshold value as a result of monitoring, then the power reception control unit (or power receiving control unit) 292 transmits a power control message to the wireless power transmitter 100 to transfer suitable power.
FIG. 5 is a block diagram illustrating a wireless power transmitter configured to have one or more transmitting coils receiving power according to an inductive coupling method that can be employed in the embodiments disclosed herein. Referring to FIG. 5, the power conversion unit 111 of the wireless power transmitter 100 according to the embodiments disclosed herein may include one or more transmitting coils 1111a-1 to 1111a-n. The one or more transmitting coils 1111a-1 to 1111a-n may be an array of partly overlapping primary coils. An active area may be determined by some of the one or more transmitting coils.
The one or more transmitting coils 1111a-1 to 1111a-n may be mounted at a lower portion of the interface surface. Furthermore, the power conversion unit 111 may further include a multiplexer 1113 for establishing and releasing the connection of some of the one or more transmitting coils 1111a-1 to 1111a-n. 
Upon detecting the location of the electronic device (or wireless power receiver) 200 placed at an upper portion of the interface surface, the power transmission control unit 112 may take the detected location of the electronic device (or wireless power receiver) 200 into consideration to control the multiplexer 1113, thereby allowing coils that can be placed in an inductive coupling relation to the receiving (Rx) coil 2911a of the electronic device (or wireless power receiver) 200 among the one or more transmitting coils 1111a-1 to 1111a-n to be connected to one another.
For this purpose, the power transmission control unit 112 may acquire the location information of the electronic device (or wireless power receiver) 200. For example, the power transmission control unit 112 may acquire the location of the electronic device (or wireless power receiver) 200 on the interface surface by the location detection unit (not shown) provided in the wireless power transmitter 100. For another example, the power transmission control unit 112 may alternatively receive a power control message indicating a strength of the wireless power signal from an object on the interface surface or a power control message indicating the identification information of the object using the one or more transmitting coils 1111a-1 to 1111a-n, respectively, and determines whether it is located adjacent to which one of the one or more transmitting coils based on the received result, thereby acquiring the location information of the electronic device (or wireless power receiver) 200.
On the other hand, the active area as part of the interface surface may denote a portion through which a magnetic field with a high efficiency can pass when the wireless power transmitter 100 transfers power to the electronic device (or wireless power receiver) 200 in a wireless manner. At this time, a single transmitting coil or one or a combination of more transmitting coils forming a magnetic field passing through the active area may be designated as a primary cell. Accordingly, the power transmission control unit 112 may determine an active area based on the detected location of the electronic device (or wireless power receiver) 200, and establish the connection of a primary cell corresponding to the active area to control the multiplexer 1113, thereby allowing the receiving (Rx) coil 2911a of the electronic device (or wireless power receiver) 200 and the coils belonging to the primary cell to be placed in an inductive coupling relation.
In the meantime, upon disposing one or more electronic devices 200 on an interface surface of the wireless power transmitter 100, which includes the one or more transmitting coils 1111a-1 to 1111a-n, the power transmission control unit 112 may control the multiplexer 1113 to allow the coils belonging to the primary cell corresponding to the position of each electronic device to be placed in the inductive coupling relation. Accordingly, the wireless power transmitter 100 may generate the wireless power signal using different coils, thereby transferring it to the one or more electronic devices in a wireless manner.
Also, the power transmission control unit 112 may set power having a different characteristic to be supplied to each of the coils corresponding to the electronic devices. Here, the wireless power transmitter 100 may transfer power by differently setting a power transfer scheme, efficiency, characteristic and the like for each electronic device. The power transmission for one or more electronic devices will be described later.
Furthermore, the power conversion unit 111 may further include an impedance matching unit (not shown) for controlling an impedance to form a resonant circuit with the coils connected thereto.
Hereinafter, a method for allowing a wireless power transmitter to transfer power according to a resonance coupling method will be disclosed with reference to FIGS. 6 through 8.
FIG. 6 is a view illustrating a concept in which power is transferred to an electronic device from a wireless power transmitter in a wireless manner according to an resonance coupling method.
First, resonance will be described in brief as follows. Resonance refers to a phenomenon in which an amplitude of vibration is remarkably increased when periodically receiving an external force having the same frequency as the natural frequency of a vibration system. Resonance is a phenomenon occurring at all kinds of vibrations such as mechanical vibration, electric vibration, and the like. Generally, when exerting a vibratory force to a vibration system from the outside, if the natural frequency thereof is the same as a frequency of the externally applied force, then the vibration becomes strong, thus increasing the width.
With the same principle, when a plurality of vibrating bodies separated from one another within a predetermined distance vibrate at the same frequency, the plurality of vibrating bodies resonate with one another, and in this case, resulting in a reduced resistance between the plurality of vibrating bodies. In an electrical circuit, a resonant circuit can be made by using an inductor and a capacitor.
When the wireless power transmitter 100 transfers power according to the inductive coupling method, a magnetic field having a specific vibration frequency is formed by alternating current power in the power transmission unit 110. If a resonance phenomenon occurs in the electronic device (or wireless power receiver) 200 by the formed magnetic field, then power is generated by the resonance phenomenon in the electronic device (or wireless power receiver) 200.
However, if the plurality of vibrating bodies resonates with each other in an electromagnetic manner as aforementioned, extremely high power transmission efficiency may be exhibited due to non affection by adjacent objects except for the vibrating bodies. An energy tunnel may be generated between the plurality of vibrating bodies which resonate with each other in the electromagnetic manner. This may be referred to as energy coupling or energy tail.
The resonance coupling disclosed herein may use an electromagnetic wave having a low frequency. When power is transferred using the electromagnetic wave having the low frequency, only a magnetic field may affect an area located within a single wavelength of the electromagnetic wave. The magnetic resonance may be generated when the wireless power transmitter 100 and the electronic device (or wireless power receiver) 200 are located within the single wavelength of the electromagnetic wave having the low frequency.
Here, in general, human bodies are sensitive to an electric field but tolerant to a magnetic field. Hence, when power is transferred using a magnetic resonance, the human bodies may be badly affected due to being exposed to the electromagnetic wave. Also, as the energy tail is generated in response to the resonance phenomenon, the form of power transmission may exhibit a non-radiative property. Consequently, upon transferring power using such electromagnetic wave, a radiative problem which occurs frequently may be solved.
The resonance coupling method may be a method for transferring power using the electromagnetic wave with the low frequency, as aforementioned. Thus, the transmitting (Tx) coil 1111b of the wireless power transmitter 100 may form a magnetic field or electromagnetic wave for transferring power in principle. However, the resonance coupling method will be described hereinafter from the perspective of a magnetic resonance, namely, a power transmission by a magnetic field.
The resonant frequency may be determined by the following formula in Equation 1.




  
    
      
        f
        =
        
          1
          
            2
            ⁢
            
              
            
            ⁢
            π
            ⁢
            
              LC
            
          
        
      
    
    
      
        [
        
          Equation
          ⁢
          
            
          
          ⁢
          1
        
        ]
      
    
  




Here, the resonant frequency (f) is determined by an inductance (L) and a capacitance (c) in a circuit. In a circuit forming a magnetic field using a coil, the inductance can be determined by a number of turns of the coil, and the like, and the capacitance can be determined by a gap between the coils, an area, and the like. In addition to the coil, a capacitive resonant circuit may be configured to be connected thereto to determine the resonant frequency.
Referring to FIG. 6, when power is transmitted in a wireless manner according to the resonance coupling method, the power conversion unit 111 of the wireless power transmitter 100 may include a transmitting (Tx) coil 1111b in which a magnetic field is formed and a resonant circuit (or resonant generation circuit) 1116 connected to the transmitting (Tx) coil 1111b to determine a specific vibration frequency. The resonant circuit (or resonant generation circuit) 1116 may be implemented by using a capacitive circuit (capacitors), and the specific vibration frequency may be determined based on an inductance of the transmitting (Tx) coil 1111b and a capacitance of the resonant circuit (or resonant generation circuit) 1116.
The configuration of a circuit element of the resonant circuit (or resonant generation circuit) 1116 may be implemented in various forms such that the power conversion unit 111 forms a magnetic field, and is not limited to a form of being connected in parallel to the transmitting (Tx) coil 1111b as illustrated in FIG. 6.
Furthermore, the power receiving unit 291 of the electronic device (or wireless power receiver) 200 may include a resonant circuit (or resonant generation circuit) 2912 and a receiving (Rx) coil 2911b to generate a resonance phenomenon by a magnetic field formed in the wireless power transmitter 100. In other words, the resonant circuit (or resonant generation circuit) 2912 may be also implemented by using a capacitive circuit, and the resonant circuit (or resonant generation circuit) 2912 is configured such that a resonant frequency determined based on an inductance of the receiving coil 2911b and a capacitance of the resonant circuit (or resonant generation circuit) 2912 has the same frequency as a resonant frequency of the formed magnetic field.
The configuration of a circuit element of the resonant circuit (or resonant generation circuit) 2912 may be implemented in various forms such that the power receiving unit 291 generates resonance by a magnetic field, and is not limited to a form of being connected in series to the receiving coil 2911b as illustrated in FIG. 6.
The specific vibration frequency in the wireless power transmitter 100 may have LTX, CTX, and may be acquired by using the Equation 1. Here, the electronic device (or wireless power receiver) 200 generates resonance when a result of substituting the LRX and CRX of the electronic device (or wireless power receiver) 200 to the Equation 1 is same as the specific vibration frequency.
According to a contactless power transfer method by resonance coupling, when the wireless power transmitter 100 and electronic device (or wireless power receiver) 200 resonate at the same frequency, respectively, an electromagnetic wave is propagated through a short-range magnetic field, and thus there exists no energy transfer between the devices if they have different frequencies.
As a result, an efficiency of contactless power transfer by the resonance coupling method is greatly affected by a frequency characteristic, whereas the effect of an alignment and distance between the wireless power transmitter 100 and the electronic device (or wireless power receiver) 200 including each coil is relatively smaller than the inductive coupling method.
Hereinafter, the configuration of a wireless power transmitter and an electronic device in the resonance coupling method applicable to the embodiments disclosed herein will be described in detail.
FIGS. 7A and 7B is a block diagram illustrating part of the wireless power transmitter 100 and electronic device (or wireless power receiver) 200 in a resonance method that can be employed in the embodiments disclosed herein.
A configuration of the power transmission unit 110 included in the wireless power transmitter 100 will be described with reference to FIG. 7A.
The power conversion unit 111 of the wireless power transmitter 100 may include a transmitting (Tx) coil 1111b, an inverter 1112, and a resonant circuit (or resonant generation circuit) 1116. The inverter 1112 may be configured to be connected to the transmitting (Tx) coil 1111b and the resonant circuit (or resonant generation circuit) 1116.
The transmitting (Tx) coil 1111b may be mounted separately from the transmitting (Tx) coil 1111a for transferring power according to the inductive coupling method, but may transfer power in the inductive coupling method and resonance coupling method using one single coil.
The transmitting (Tx) coil 1111b, as described above, forms a magnetic field for transferring power. The transmitting (Tx) coil 1111b and the resonant circuit (or resonant generation circuit) 1116 generate resonance when alternating current power is applied thereto, and at this time, a vibration frequency may be determined based on an inductance of the transmitting (Tx) coil 1111b and a capacitance of the resonant circuit (or resonant generation circuit) 1116.
For this purpose, the inverter 1112 transforms a DC input obtained from the power supply unit 190 into an AC waveform, and the transformed AC current is applied to the transmitting (Tx) coil 1111b and the resonant circuit (or resonant generation circuit) 1116.
In addition, the power conversion unit 111 may further include a frequency adjustment unit 1117 for changing a resonant frequency of the power conversion unit 111. The resonant frequency of the power conversion unit 111 is determined based on an inductance and/or capacitance within a circuit constituting the power conversion unit 111 by Equation 1, and thus the power transmission control unit 112 may determine the resonant frequency of the power conversion unit 111 by controlling the frequency adjustment unit 1117 to change the inductance and/or capacitance.
The frequency adjustment unit 1117, for example, may be configured to include a motor for adjusting a distance between capacitors included in the resonant circuit (or resonant generation circuit) 1116 to change a capacitance, or include a motor for adjusting a number of turns or diameter of the transmitting (Tx) coil 1111b to change an inductance, or include active elements for determining the capacitance and/or inductance
On the other hand, the power conversion unit 111 may further include a power sensing unit 1115. The operation of the power sensing unit 1115 is the same as the foregoing description.
Referring to FIG. 7B, a configuration of the power supply unit 290 included in the electronic device (or wireless power receiver) 200 will be described. The power supply unit 290, as described above, may include the receiving (Rx) coil 2911b and resonant circuit (or resonant generation circuit) 2912.
In addition, the power receiving unit 291 of the power supply unit 290 may further include a rectifier (or rectifying) circuit 2913 for converting an AC current generated by resonance phenomenon into DC. The rectifier (or rectifying) circuit 2913 may be configured similarly to the foregoing description.
Furthermore, the power receiving unit 291 may further include a power sensing unit 2914 for monitoring a voltage and/or current of the rectified power. The power sensing unit 2914 may be configured similarly to the foregoing description.
FIG. 8 is a block diagram illustrating a wireless power transmitter configured to have one or more transmitting coils receiving power according to a resonance coupling method that can be employed in the embodiments disclosed herein. Referring to FIG. 8, the power conversion unit 111 of the wireless power transmitter 100 according to the embodiments disclosed herein may include one or more transmitting coils 1111b-1 to 1111b-n and resonant (or resonant generation) circuits (1116-1 to 1116-n) connected to each transmitting coils. Furthermore, the power conversion unit 111 may further include a multiplexer 1113 for establishing and releasing the connection of some of the one or more transmitting coils 1111b-1 to 1111b-n. 
The one or more transmitting coils 1111b-1 to 1111b-n may be configured to have the same vibration frequency, or some of them may be configured to have different vibration frequencies. It is determined by an inductance and/or capacitance of the resonant (or resonant generation) circuits (1116-1 to 1116-n) connected to the one or more transmitting coils 1111b-1 to 1111b-n, respectively.
In the meantime, when one or more electronic devices 200 are disposed in an active area or a detection area of the wireless power transmitter 100 including the one or more transmitting coils 1111b-1 to 1111b-n, the power transmission control unit 112 may control the multiplexer 1113 to allow the electronic devices to be placed in different resonance coupling relations. Accordingly, the wireless power transmitter 100 may wirelessly transfer power to the one or more electronic devices by generating the wireless power signal using different coils.
In addition, the power transmission control unit 112 may set power with a different characteristic to be supplied to each of the coils corresponding to the electronic devices. Here, the wireless power transmitter 100 may transfer power by differently setting a power transmission scheme, a resonant frequency, efficiency, a characteristic and the like for each electronic device. The power transmission for one or more electronic devices will be described later with reference to FIG. 28. For this purpose, the frequency adjustment unit 1117 may be configured to change an inductance and/or capacitance of the resonant circuits (1116-1 to 1116-n) connected to the one or more transmitting coils 1111b-1 to 1111b-n, respectively.
On the other hand, hereinafter, an example of the wireless power transmitter implemented in the form of a wireless charger will be described.
FIG. 9 is a block diagram illustrating a wireless power transmitter further including an additional element in addition to the configuration illustrated in FIG. 2A. Referring to FIG. 9, the wireless power transmitter 100 may further include a sensor unit 120, a communication unit 130, an output unit 140, a memory 150, and a control unit (or Controller) 180 in addition to the power transmission unit 110 and power supply unit 190 for supporting at least one of the foregoing inductive coupling method and resonance coupling method.
The control unit (or Controller) 180 controls the power transmission unit 110, the sensor unit 120, the communication unit 130, the output unit 140, the memory 150, and the power supply unit 190.
The control unit (or Controller) 180 may be implemented by a module separated from the power transmission control unit 112 in the power transmission unit 110 described with reference to FIG. 2 or may be implemented by a single module.
The sensor unit 120 may include a sensor for detecting the location of the electronic device (or wireless power receiver) 200. The location information detected by the sensor unit 120 may be used for allowing the power transmission unit 110 to transfer power in an efficient manner.
For instance, in case of wireless power transfer according to the inductive coupling method, the sensor unit 120 may be operated as a detection unit, and the location information detected by the sensor unit 120 may be used to move or rotate the transmitting (Tx) coil 1111a in the power transmission unit 110.
Furthermore, for example, the wireless power transmitter 100 configured to include the foregoing one or more transmitting coils may determine coils that can be placed in an inductive coupling relation or resonance coupling relation to the receiving coil of the electronic device (or wireless power receiver) 200 among the one or more transmitting coils based on the location information of the electronic device (or wireless power receiver) 200.
On the other hand, the sensor unit 120 may be configured to monitor whether or not the electronic device (or wireless power receiver) 200 approaches a chargeable region. The approach or non-approach detection function of the sensor unit 120 may be carried out separately from the function of allowing the power transmission control unit 112 in the power transmission unit 110 to detect the approach or non-approach of the electronic device (or wireless power receiver) 200.
The communication unit 130 performs wired or wireless data communication with the electronic device (or wireless power receiver) 200. The communication unit 130 may include an electronic component for at least any one of BluetoothTM, Zigbee, Ultra Wide Band (UWB), Wireless USB, Near Field Communication (NFC), and Wireless LAN.
The output unit 140 may include at least one of a display unit 141 and an audio output unit (or sound output unit) 142. The display unit 141 may include at least one of a liquid crystal display (LCD), a thin film transistor-liquid crystal display (TFT-LCD), an organic light-emitting diode (OLED), a flexible display, and a three-dimensional (3D) display. The display unit 141 may display a charging state under the control of the control unit (or Controller) 180.
The memory 150 may include at least one storage medium of a flash memory type, a hard disk type, a multimedia card micro type, a card type memory (e.g., SD or XD memory), a random access memory (RAM), a static random access memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a programmable read-only memory (PROM), a magnetic memory, a magnetic disk, an optical disk, and the like. The wireless power transmitter 100 may operate in association with a web storage performing the storage function of the memory 150 on the Internet. A program or commands performing the foregoing functions of the wireless power transmitter 100 may be stored in the memory 150. The control unit (or Controller) 180 may perform the program or commands stored in the memory 150 to transmit power in a wireless manner. A memory controller (not shown) may be used to allow other constituent elements (e.g., control unit (or Controller) 180) included in the wireless power transmitter 100 to access the memory 150.
However, it would be easily understood by those skilled in the art that the configuration of a wireless power transmitter according to the embodiment disclosed herein may be applicable to an apparatus, such as a docking station, a terminal cradle device, and an electronic device, and the like, excluding a case where it is applicable to only a wireless charger.
FIG. 10 is view illustrating a configuration in case where an electronic device (or wireless power receiver) 200 according to the embodiments disclosed herein is implemented in the form of a mobile terminal.
The mobile communication terminal 200 may include a power supply unit 290 illustrated in FIG. 2A, 2B, 4A, 4B, 7A or 7B.
Furthermore, the terminal 200 may further include a wireless communication unit 210, an Audio/Video (A/V) input unit 220, a user input unit 230, a sensing unit 240, an output unit 250, a memory 260, an interface unit 270, and a controller 280. FIG. 10 illustrates the terminal 100 having various components, but it is understood that implementing all of the illustrated components is not a requirement. Greater or fewer components may alternatively be implemented.
Hereinafter, each component is described in sequence.
The wireless communication unit 210 may typically include one or more modules which permit wireless communications between the terminal 200 and a wireless communication system or between the terminal 200 and a network within which the terminal 200 is located. For example, the wireless communication unit 210 may include a broadcast receiving module 211, a mobile communication module 212, a wireless internet module 213, a short-range communication module 214, a position information module 215 and the like.
The broadcast receiving module 211 receives a broadcast signal and/or broadcast associated information from an external broadcast managing entity via a broadcast channel.
The broadcast channel may include a satellite channel and a terrestrial channel. The broadcast center may indicate a server which generates and transmits a broadcast signal and/or broadcast associated information or a server which receives a pre-generated broadcast signal and/or broadcast associated information and sends them to the portable terminal. The broadcast signal may be implemented as a TV broadcast signal, a radio broadcast signal, and a data broadcast signal, among others. The broadcast signal may further include a data broadcast signal combined with a TV or radio broadcast signal.
Examples of broadcast associated information may denote information associated with a broadcast channel, a broadcast program, a broadcast service provider, and the like. The broadcast associated information may be provided via a mobile communication network. In this case, it may be received by the mobile communication module 212.
The broadcast associated information may be implemented in various formats. For instance, broadcast associated information may include Electronic Program Guide (EPG) of Digital Multimedia Broadcasting (DMB), Electronic Service Guide (ESG) of Digital Video Broadcast-Handheld (DVB-H), and the like.
The broadcast receiving module 211 may be configured to receive digital broadcast signals transmitted from various types of broadcast systems. Such broadcast systems may include Digital Multimedia Broadcasting-Terrestrial (DMB-T), Digital Multimedia Broadcasting-Satellite (DMB-S), Media Forward Link Only (MediaFLO), Digital Video Broadcast-Handheld (DVB-H), Integrated Services Digital Broadcast-Terrestrial (ISDB-T) and the like. The broadcast receiving module 211 may be configured to be suitable for every broadcast system transmitting broadcast signals as well as the digital broadcasting systems.
Broadcast signals and/or broadcast associated information received via the broadcast receiving module 211 may be stored in a suitable device, such as a memory 260.
The mobile communication module 212 transmits/receives wireless signals to/from at least any one of a base station, an external portable terminal, and a server on a mobile communication network. The wireless signal may include audio call signal, video (telephony) call signal, or various formats of data according to transmission/reception of text/multimedia messages.
The wireless internet module 213 supports wireless Internet access for the mobile terminal 200. This module may be internally or externally coupled to the terminal 100. Examples of such wireless Internet access may include Wireless LAN (WLAN) (Wi-Fi), Wireless Broadband (Wibro), Worldwide Interoperability for Microwave Access (Wimax), High Speed Downlink Packet Access (HSDPA) and the like.
The short-range communication module 214 denotes a module for short-range communications. Suitable technologies for implementing this module may include Bluetooth, Radio Frequency IDentification (RFID), Infrared Data Association (IrDA), Ultra-WideBand (UWB), ZigBee, and the like. On the other hand, Universal Serial Bus (USB), IEEE 1394, Thunderbolt of Intel technology, and the like, may be used for wired short-range communication.
The wireless internet module 213 or the short-range communication module 214 may establish data communication connection to the wireless power transmitter 100.
Through the established data communication, when there is an audio signal to be outputted while transferring power in a wireless manner, the wireless internet module 213 or the short-range communication module 214 may transmit the audio signal to the wireless power transmitter 100 through the short-range communication module. Furthermore, through the established data communication, when there is information to be displayed, the wireless internet module 213 or the short-range communication module 214 may transmit the information to the wireless power transmitter 100. Otherwise, the wireless internet module 213 or the short-range communication module 214 may transmit an audio signal received through a microphone integrated in the wireless power transmitter 100. Furthermore, the wireless internet module 213 or the short-range communication module 214 may transmit the identification information (e.g., phone number or device name in case of a portable phone) of the mobile terminal 200 to the wireless power transmitter 100 through the established data communication.
The position information module 215 is a module for acquiring a position of the terminal. An example of the position information module 215 may include a Global Position System (GPS) module.
Referring to FIG. 10, the A/V input unit 220 is configured to provide audio or video signal input to the portable terminal. The A/V input unit 220 may include a camera 221 and a microphone 222. The camera 221 processes image frames of still or moving images obtained by an image sensor in a video call mode or a capture more. The processed image frames may be displayed on the display unit 251.
The image frames processed by the camera 221 may be stored in the memory 260 or transmitted to the exterior via the wireless communication unit 210. Two or more cameras 221 may be provided therein according to the use environment.
The microphone 222 may receive an external audio signal by a microphone in a phone call mode, a recording mode, a voice recognition mode, or the like to process it into electrical audio data. The processed audio data is converted and outputted into a format transmittable to a mobile communication base station via the mobile communication module 212 in case of the phone call mode. The microphone 222 may include various noise removal algorithms to remove noises generated while receiving the external audio signal.
The user input unit 230 may generate input data to allow the user to control the operation of the terminal. The user input unit 230 may include a keypad, a dome switch, a touchpad (e.g., static pressure/capacitance), a jog wheel, a jog switch and the like.
The sensing unit 240 may include a proximity sensor 241, a pressure sensor 242, a motion sensor 243, and the like. The proximity sensor 241 detects an object approaching the mobile terminal 200, or the presence or absence of an object existing adjacent to the mobile terminal 200, and the like without any mechanical contact. The proximity sensor 241 may detect a proximity object using a change of the AC magnetic field or static magnetic field, a change rate of the electrostatic capacity, or the like. Two or more proximity sensors 241 may be provided according to the aspect of configuration.
The pressure sensor 242 may detect whether or not a pressure is applied to the mobile terminal 200, a size of the pressure, and the like. The pressure sensor 242 may be provided at a portion where the detection of a pressure is required in the mobile terminal 200 according to the use environment. When the pressure sensor 242 is provided in the display unit 251, it may be possible to identify a touch input through the display unit 251 and a pressure touch input by which a pressure larger than the touch input is applied according to a signal outputted from the pressure sensor 242. Furthermore, it may be possible to know a size of the pressure applied to the display unit 251 during the input of a pressure touch.
The motion sensor 243 detects the location or movement of the mobile terminal 200 using an acceleration sensor, a gyro sensor, and the like. The acceleration sensor used in the motion sensor 243 is an element for converting an acceleration change in any one direction into an electrical signal. Two or three axes are typically integrated into a package to constitute an acceleration sensor, and only one Z-axis may be required according to the use environment. Accordingly, when an acceleration sensor in the direction of X-axis or Y-axis should be used instead of the direction of Z-axis due to any reason, the acceleration sensor may be erected and mounted on a main substrate using a separate piece substrate. Furthermore, the gyro sensor is a sensor for measuring an angular speed of the mobile terminal 200 in a rotational movement to detect a rotated angle with respect to each reference direction. For instance, the gyro sensor may detect each rotational angle, i.e., azimuth, pitch and roll, with reference to three directional axes.
The output unit 250 is provided to output visual, auditory, or tactile information. The output unit 250 may include a display unit 251, an audio output module 252, an alarm unit 253, a haptic module 254, and the like.
The display unit 251 may display (output) information processed in the terminal 200. For example, when the terminal is in a phone call mode, the display unit 251 will provide a User Interface (UI) or Graphic User Interface (GUI) associated with the call. When the terminal is in a video call mode or a capture mode, the display unit 251 may display images captured and/or received, UI, or GUI.
The display unit 251 may include at least one of a liquid crystal display (LCD), a thin film transistor-liquid crystal display (TFT-LCD), an organic light-emitting diode (OLED), a flexible display, a three-dimensional (3D) display, and the like.
Some of those displays may be configured as a transparent type or a light transmission type through which the outside is visible, which is referred to as a transparent display. A representative example of the transparent display may include a Transparent OLED (TOLED), or the like. The rear surface of the display unit 151 may also be implemented to be optically transparent. Under this configuration, the user can view an object positioned at a rear side of the terminal body through a region occupied by the display unit 251 of the terminal body.
The display unit 251 may be implemented in two or more in number according to a configured aspect of the terminal 200. For instance, a plurality of the display units 251 may be arranged on one surface to be spaced apart from or integrated with each other, or may be arranged on different surfaces.
Here, if the display unit 251 and a touch sensitive sensor (referred to as a touch sensor) have a layered structure therebetween, the display unit 251 may be used as an input device rather than an output device. The touch sensor may be implemented as a touch film, a touch sheet, a touch pad, and the like.
The touch sensor may be configured to convert changes of a pressure applied to a specific part of the display unit 251, or a capacitance occurring from a specific part of the display unit 251, into electric input signals. Also, the touch sensor may be configured to sense not only a touched position and a touched area, but also a touch pressure.
When touch inputs are sensed by the touch sensors, corresponding signals are sent to a touch controller. The touch controller processes the received signals, and then transmits corresponding data to the controller 280. Accordingly, the controller 280 may sense which region of the display unit 151 has been touched.
The proximity sensor 241 may be arranged at an inner region of the terminal covered by the touch screen, or near the touch screen. The proximity sensor refers to a sensor to sense the presence or absence of an object approaching a surface to be sensed, or an object disposed near a surface to be sensed, using an electromagnetic field or infrared rays without a mechanical contact. The proximity sensor has a longer lifespan and a more enhanced utility than a contact sensor.
The proximity sensor may include a transmissive type photoelectric sensor, a direct reflective type photoelectric sensor, a mirror reflective type photoelectric sensor, a high-frequency oscillation proximity sensor, a capacitance type proximity sensor, a magnetic type proximity sensor, an infrared rays proximity sensor, and so on. When the touch screen is implemented as a capacitance type, proximity of a pointer to the touch screen is sensed by changes of an electromagnetic field. In this case, the touch screen (touch sensor) may be categorized into a proximity sensor.
Hereinafter, for the sake of brief explanation, a status that the pointer is positioned to be proximate onto the touch screen without contact will be referred to as a “proximity touch”, whereas a status that the pointer substantially comes in contact with the touch screen will be referred to as a “contact touch”. For the position corresponding to the proximity touch of the pointer on the touch screen, such position corresponds to a position where the pointer faces perpendicular to the touch screen upon the proximity touch of the pointer.
The proximity sensor senses proximity touch, and proximity touch patterns (e.g., distance, direction, speed, time, position, moving status, etc.). Information relating to the sensed proximity touch and the sensed proximity touch patterns may be output onto the touch screen.
The audio output module 252 may output audio data received from the wireless communication unit 210 or stored in the memory 260, in a call-receiving mode, a call-placing mode, a recording mode, a voice recognition mode, a broadcast reception mode, and so on. The audio output module 252 may output audio signals relating to functions performed in the terminal 200, e.g., sound alarming a call received or a message received, and so on. The audio output module 252 may include a receiver, a speaker, a buzzer, and so on.
The alarm 253 outputs signals notifying the occurrence of an event from the terminal 200. The event occurring from the terminal 100 may include call received, message received, key signal input, touch input, and so on. The alarm 253 may output not only video or audio signals, but also other types of signals such as signals notifying occurrence of events in a vibration manner. Since the video or audio signals can be output through the display unit 251 or the audio output unit 252, the display unit 251 and the audio output module 252 may be categorized into part of the alarm 253.
The haptic module 254 generates various tactile effects which a user can feel. A representative example of the tactile effects generated by the haptic module 254 includes vibration. Vibration generated by the haptic module 254 may have a controllable intensity, a controllable pattern, and so on. For instance, different vibration may be output in a synthesized manner or in a sequential manner.
The haptic module 254 may generate various tactile effects, including not only vibration, but also arrangement of pins vertically moving with respect to a skin being contacted, air injection force or air suction force through an injection hole or a suction hole, touch by a skin surface, presence or absence of contact with an electrode, effects by stimulus such as an electrostatic force, reproduction of cold or hot feeling using a heat absorbing device or a heat emitting device, and the like.
The haptic module 254 may be configured to transmit tactile effects through the user's direct contact, or the user's muscular sense using a finger or a hand. The haptic module 254 may be implemented in two or more in number according to the configuration of the terminal 200.
The memory 260 may store a program for the processing and control of the controller 280. Alternatively, the memory 260 may temporarily store input/output data (e.g., phonebook data, messages, still images, video and the like). Also, the memory 260 may store data related to various patterns of vibrations and audio output upon the touch input on the touch screen.
In some embodiments, software components including an operating system (not shown), a module performing a wireless communication unit 210 function, a module operating together with the user input unit 230, a module operating together with the A/V input unit 220, a module operating together with the output unit 250 may be stored in the memory 260. The operating system (e.g., LINUX, UNIX, OS X, WINDOWS, Chrome, Symbian, iOS, Android, VxWorks, or other embedded operating systems) may include various software components and/or drivers to control system tasks such as memory management, power management, and the like.
In addition, the memory 260 may store a setup program associated with contactless power transfer or wireless charging. The setup program may be implemented by the controller 280.
Furthermore, the memory 260 may store an application associated with contactless power transfer (or wireless charging) downloaded from an application providing server (for example, an app store). The wireless charging related application is a program for controlling wireless charging transmission, and thus the electronic device (or wireless power receiver) 200 may receive power from the wireless power transmitter 100 in a wireless manner or establish connection for data communication with the wireless power transmitter 100 through the relevant program.
The memory 260 may be implemented using any type of suitable storage medium including a flash memory type, a hard disk type, a multimedia card micro type, a memory card type (e.g., SD or xD memory), a random access memory (RAM), a static random access memory (SRAM), a read-only memory (ROM), an electrically erasable programmable read-only memory (EEPROM), a programmable read-only memory (PROM), a magnetic memory, a magnetic disk, an optical disk, and the like. Also, the terminal 200 may be operated in association with a web storage performing the storage function of the memory 150 on the Internet.
The interface unit 270 may generally be implemented to interface the portable terminal with all external devices. The interface unit 270 may allow a data reception from an external device, a power delivery to each component in the terminal 200, or a data transmission from the terminal 200 to an external device. The interface unit 270 may include, for example, wired/wireless headset ports, external charger ports, wired/wireless data ports, memory card ports, ports for coupling devices having an identification module, audio input/output (I/O) ports, video input/output (I/O) ports, earphone ports, and the like.
The identification module may be configured as a chip for storing various information required to authenticate an authority to use the terminal 200, which may include a User Identity Module (UIM), a Subscriber Identity Module (SIM), and the like. Also, the device having the identification module (hereinafter, referred to as “identification device”) may be implemented in a type of smart card. Hence, the identification device can be coupled to the terminal 200 via a port.
Also, the interface unit may serve as a path for power to be supplied from an external cradle to the terminal 200 when the terminal 100 is connected to the external cradle or as a path for transferring various command signals inputted from the cradle by a user to the terminal 200. Such various command signals or power inputted from the cradle may operate as signals for recognizing that the terminal 200 has accurately been mounted to the cradle.
The controller 280 typically controls the overall operations of the terminal 200. For example, the controller 280 performs the control and processing associated with telephony calls, data communications, video calls, and the like. The controller 280 may include a multimedia module 281 for multimedia playback. The multimedia module 281 may be implemented within the controller 280, or implemented separately from the controller 280.
The controller 280 can perform a pattern recognition processing so as to recognize a writing input or image drawing input carried out on the touch screen as a text or image.
The controller 280 performs wired or wireless charging according to the user input or internal input. Here, the internal input represents a signal for notifying that an induced current generated from a secondary coil within the terminal has been detected.
When the foregoing wireless charging is carried out, an operation of allowing the controller 280 to control each constituent element will be described in detail below with reference to the operation phase in FIG. 14. As described above, the power reception control unit (or power receiving control unit) 292 within the power supply unit 290 may be implemented to be included in the controller 280, and in the present disclosure, it should be understood that the controller 280 performs the operation by the power reception control unit (or power receiving control unit) 292.
The power supply unit 290 receives internal and external power under the control of the controller 280 to supply power required for the operation of each constituent element.
The power supply unit 290 is provided with a battery 299 for supplying power to each constituent element of the terminal 200, and the battery 299 may include a charger (or charging unit) 298 for performing wired or wireless charging.
The present disclosure discloses a mobile terminal as an example of the apparatus for receiving power in a wireless manner, but it would be easily understood by those skilled in the art that the configuration according to the embodiment disclosed herein may be applicable to a stationary terminal, such as a digital TV, a desktop computer, and the like, excluding a case where it is applicable to only the mobile terminal.
FIG. 11 is a front perspective view of a wireless power transmitter 300 according to an embodiment of the present invention.
A body 303 of the wireless power transmitter 300 comprises a case (casing, housing, cover, etc.) which forms the appearance of the wireless power transmitter. In this embodiment, the case may include a front case 301 and a rear case 302. A space formed by the front case 301 and the rear case 302 may accommodate various components therein. At least one intermediate case may be additionally disposed between the front case 301 and the rear case 302.
Such cases may be formed by injection-molded synthetic resin, or may be formed using a metallic material such as stainless steel (STS) or titanium (Ti).
On the body 303, may be disposed an output unit such as a display unit 341 or an audio output unit 342, a user input unit 360, a socket 389 for supplying power to the body 303, an interface (not shown) to which an external device is coupled, etc.
The display unit 341 may be formed on an upper surface of the front case 301. The user input unit 360, the socket 389, etc. may be disposed on side surfaces of the front case 301 and the rear case 302.
The user input unit 360 is manipulated to receive a command for controlling the operation of the mobile terminal 100, and may include a plurality of manipulating units 361 and 362. The manipulating units 361 and 362 may be referred to as ‘manipulating portions’, and may include any type of ones that can be manipulated in a user's tactile manner.
Contents input by the first manipulating unit 361 or the second manipulating unit 362 may be set in various manners. For instance, the first manipulating unit 361 may be configured to input commands such as starting and ending a wireless charging operation. And the second manipulating unit 362 may be configured to input commands such as controlling the size of a sound output from the audio output unit 342, or controlling brightness of the display unit 341.
A mounting surface 301a, which is configured to mount thereon an electronic device 200 to be charged, is formed on an upper surface of the body 303. Once the electronic device 200 is disposed on the mounting surface 301a, a sensor of the body 303 may sense the mounted state of the electronic device 200. Then, the electronic device 200 may be wirelessly charged.
FIG. 12 is an exploded perspective view of FIG. 11. Referring to FIG. 12, a coil module 370, a circuit board 355 and a blowing module 325 (refer to FIGS. 13A and 13B) may be disposed at a space formed between the front case 301 and the rear case 302.
As aforementioned, once the electronic device 200 is disposed on the mounting surface 301a, the coil module 370 transmits power to the electronic device 200 in a wireless manner.
The coil module 370 may include a fixing plate 372 and a coil 371. The coil module 370 may be fixed to the rear case 302 by the fixing plate 372. The fixing plate 372 may be formed of a material having high thermal conductivity, so that heat generated from the coil 371 can be emitted to outside of the rear case 302. Part of the rear case 302, which is covered by the fixing plate 372, may include one or more openings so as to facilitate radiation of heat from the fixing plate 372.
The coil 371 may be formed as at least one conductive line is wound on a cylindrical body. A magnet 373 may be disposed on an inner circumferential surface of a cylindrical coil according to a wireless charging type.
The circuit board 355 is disposed near the coil module 370. The circuit board 355 includes various types of devices, and generates a wireless power signal if power is supplied thereto. Then, the circuit board 355 provides the generated wireless power signal to the coil module 370. For generation of a wireless power signal, the circuit board 355 may include one or more devices which constitute a power converter, a power transmission controller or a modulation/demodulation unit.
The blowing module 325 is configured to discharge a fluid toward a guide module 380. For instance, the blowing module 325 may discharge a fluid under a structure where a fan is installed in a housing and the fan is rotated by a motor. However, in this case, noise may occur. Further, the motor and the fan should be formed to have a size more than a prescribed value, for cooling efficiency. This may cause a limitation in designing the motor and the fan.
The blowing module 325, configured to discharge a fluid by transforming a diaphragm 325b in a curved manner by a piezoelectric device (refer to FIG. 14), may be applied to the wireless power transmitter 300 according to the present invention. The blowing module 325 is configured to discharge a fluid when supplied with an external voltage, by up-down moving part of the diaphragm 325b disposed in the housing, using an actuator including a piezoelectric device. As the diaphragm 325b, a metallic plate having a high Young's modulus may be used.
The fluid may be air or cooling water.
FIGS. 13A and 13B are perspective views of the front case 301 of FIG. 11.
As shown in FIGS. 13A and 13B, the guide module 380 may be integrally formed with the case 301 to thus form a passage of a fluid, so that heat generated from the coil module 370 can be discharged to outside of the body 303. The guide module 380 may be extended up to outside of the body 303 through the blowing module 325 and the coil module 370, sequentially. One or more openings 383 may be penetratingly formed at the front case 301 and the rear case 302 which constitute the body 303. The guide module 380 may be configured to discharge heat generated from inside of the body 303 to outside through the opening 383. That is, the guide module 380 is formed so that a fluid from the blowing module 325 can be discharged to outside of the body 303 after cooling the coil module 370.
The guide module 380 may be integrally formed with one of the front case 301 and the rear case 302 which implement the appearance of the body 303.
The guide module 380 may comprise a coil cooling portion 381 and a circuit board cooling portion 382.
The coil cooling portion 381 has a shape corresponding to an outer circumference of the coil 371. In this case, the coil cooling portion 381 may be formed to enclose the outer circumference of the coil 371. For instance, as shown in FIG. 13A, the coil cooling portion 381 may have a shape as partition walls 381a and 381b thereof are protruding from the front case 301, and the coil 371 may be disposed at a space formed between the partition walls 381a and 381b. In this case, an inner wall 381a of the coil cooling portion 381 may be formed of a material having high thermal conductivity. Under such configuration, heat generated from the coil 371 can be transferred to the coil cooling portion 381.
As shown in FIG. 13B, a region on one surface of the front case 301 may be recessed in correspondence to the coil 371, thereby forming a space. The coil 371 may be disposed at the space.
As shown in FIG. 13A, the coil cooling portion 381 may be provided with an inner wall 381a and an outer wall 381b. Alternatively, as shown in FIG. 13B, the coil cooling portion 381′ may be provided with only an outer wall.
Still alternatively, the coil cooling portion 381 may be configured as an annular pipe, and part of the coil cooling portion 381 contacting the coil 371 may be formed of material having high thermal conductivity. Under such configuration, heat generated from the coil 371 may be transferred to the coil cooling portion 381.
One side of the coil cooling portion 381 may be communicated with the blowing module 325, and another side thereof may be communicated with the circuit board cooling portion 382. Under such configuration, a fluid generated from the blowing module 325 may be introduced to one side of the coil cooling portion 381. Then, the fluid may be discharged to another side of the coil cooling portion 381 to be connected to the circuit board cooling portion 382, while moving with enclosing the coil 371. Therefore, a fluid introduced to one side of the coil cooling portion 381 from the blowing module 325 may move along the coil cooling portion 381 to thus be discharged to another side of the coil cooling portion 381. That is, the coil cooling portion 381 may be a passage along which a fluid discharged from the blowing module 325 moves to the circuit board cooling portion 382.
One side of the circuit board cooling portion 382 may be connected to the coil cooling portion 381, and another side thereof may be connected to the opening 383 of the case. The circuit board cooling portion 382 may be a passage along which a fluid from the coil cooling portion 381 is discharged to outside of the body 303 through the opening 383.
The circuit board cooling portion 382 may be configured as a pipe. Alternatively, the circuit board cooling portion 382 may be configured as a pair of ribs 382a and 382b protruding from one surface of the case. Here, a space formed by the case 301, the ribs 382a and 382b, and the circuit board 355 may define a passage through which a fluid moves.
In order to increase a moving speed of a fluid inside the guide module, a sectional surface of the coil cooling portion may be variable according to a position. Generally, the larger a sectional area is, the slower a fluid moves. However, as a sectional area is increased, a contact area is increased to enhance cooling efficiency. For instance, if part of the coil cooling portion adjacent to the blowing module has a first sectional area, part of the coil cooling portion contacting the circuit board cooling portion may have a second sectional area larger than the first sectional area. The reason is in order to enhance cooling efficiency even if a moving speed of a fluid is slow. The circuit board cooling portion contacting the coil cooling portion having the second sectional area may be configured so that its sectional area can be increased or decreased toward one side. That is, for control of a moving speed of a fluid, the circuit board cooling portion may have its sectional area gradually increased or decreased toward a direction far from the coil cooling portion.
FIG. 14 is a sectional view taken along line ‘IV-IV’ in FIG. 11.
Referring to FIG. 14, once the blowing module 325 operates, a fluid is discharged from the blowing module 325 to thus be discharged to outside of the body 303 through the guide module 380.
The fluid discharged from the blowing module 325 primarily cools the coil module 370 while passing through the coil cooling portion 381. Then, the fluid secondarily cools the circuit board cooling portion 382 while passing through the circuit board cooling portion 382 connected to the coil cooling portion 381.
In a case where the coil cooling portion 381 is formed to have a ring shape and a partition wall is formed between the coil cooling portion 381 and the coil 371, the fluid discharged to the guide module 380 may cool heat transferred to the partition wall.
On the other hand, in a case where no partition wall is formed between the coil cooling portion 381 and the coil 371 as the coil cooling portion 381 is concaved from one surface of the front case 301, the fluid discharged to the guide module 380 may cool the coil 371 with directly contacting the coil 371.
FIG. 15 is a conceptual view illustrating a coupled state of a pad 385 to the front case of FIG. 13.
The guide module 380 is integrally formed with the front case 301, and the circuit board cooling portion 382 is disposed to cover at least part of the circuit board 355.
The pad 385 may be disposed between the circuit board 355 and the circuit board cooling portion 382, so that heat generated from the circuit board 355 can be smoothly discharged to outside of the body 303. The pad 385 may be formed of a material having high thermal conductivity for enhanced heat transfer from the circuit board 355 to the circuit board cooling portion 382.
One surface of the pad 385 may be disposed to cover part of the circuit board 355, and another surface thereof may contact the circuit board cooling portion 382. In this case, at least part of the pad 385 may be disposed between the circuit board cooling portion 382 and the circuit board 355. That is, if the circuit board cooling portion 382 is configured in the form of a groove, the pad 385 is disposed to cover the groove. In this case, the pad 385 may be disposed so that a fluid can pass through a space between the pad 385 and the front case 301.
Cooling efficiency of the wireless power transmitter 300 according to the preferred embodiment where both of the blowing module 325 and the guide module 380 are provided, was compared with that of a wireless power transmitter according to a comparative embodiment where only the blowing module 325 is provided. As experimental results, temperature of the coil module 370 was increased up to about 62° C. in the comparative embodiment when the electronic device 200 is charged, while temperature of the coil module 370 was increased up to about 47° C. in the preferred embodiment. Further, temperature of the circuit board 355 was increased up to about 40° C. in the comparative embodiment when the electronic device 200 is charged, while temperature of the circuit board 355 was increased up to about 29° C. in the preferred embodiment.
FIG. 16 is a modification embodiment of a wireless power transmitter, which illustrates an example of the blowing module 325 configured to be rotatable. As shown in FIG. 16, a blowing module 325′ may be coupled to a supporting plate 326 fixed to one of the front case 301 and the rear case 302. More specifically, a shaft 327 is protruding toward two sides of a housing of the blowing module 325′, and the shaft 327 is coupled to the supporting plate 326. Under such configuration, the blowing module 325 can rotate around the shaft 327.
Although not shown, a diaphragm 325b may be rotatably coupled to the supporting plate 326.
As the blowing module 325 is configured to be rotatable, a discharge amount of a fluid to the guide module 380 per unitary hour can be increased.
FIG. 17 is still another modification embodiment of a wireless power transmitter, which illustrates an example where an outer guide is formed at the front case.
If temperature of the wireless power transmitter 300 is increased, temperature of the electronic device 200 attached to the wireless power transmitter 300 may be also increased.
This embodiment is configured to prevent the temperature increase of the electronic device 200 due to the wireless power transmitter 300.
Referring to FIG. 17, protrusion 301c are formed on a mounting surface 301a of the front case 301, the mounting surface 301a on which the electronic device 200 is positioned. Due to the protrusions 301c, the electronic device 200 can be spaced from the front case 301. This can reduce heat transfer from the wireless power transmitter 300 to the electronic device 200 resulting from direct contact therebetween.
Further, due to the protrusions 301c, a contact area between the wireless power transmitter 300 and the electronic device 200 can be reduced.
The front case 301 may further comprise an outer guide 301b so that part of a fluid discharged from the blowing module 325 can be discharged to a space between the electronic device 200 and the front case 301.
The outer guide may guide air discharged from the blowing module 325 to be discharged to a space between the protrusions 301c. Under such configuration, the amount of heat transferred to the electronic device 200 from the wireless power transmitter 300 can be significantly reduced.
Various embodiments described herein may be implemented in a computer-readable medium using, for example, software, hardware, or some combination thereof.
For a hardware implementation, the embodiments described herein may be implemented within one or more of Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), Programmable Logic Devices (PLDs), Field Programmable Gate Arrays (FPGAs), processors, controllers, micro-controllers, micro processors, other electronic units designed to perform the functions described herein, or a selective combination thereof. In some cases, such embodiments may be implemented by the controller 180 or the power transmission control unit 112 of the wireless power transmitter 100.
For software implementation, the embodiments such as procedures and functions may be implemented together with separate software modules each of which performs at least one of functions and operations. The software codes can be implemented with a software application written in any suitable programming language. Also, the software codes may be stored in the memory 150 of the wireless power transmitter 100, and executed by the controller 180 or the power transmission control unit 112.
It is obvious that the configuration of the wireless power transmitter according to the present invention may be also applicable to a docking station, a terminal cradle device, and other electronic device, except for a case where the configuration of the wireless power transmitter is applicable only to a wireless charger.
The foregoing embodiments and advantages are merely exemplary and are not to be considered as limiting the present disclosure. The present teachings can be readily applied to other types of apparatuses. This description is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art. The features, structures, methods, and other characteristics of the exemplary embodiments described herein may be combined in various ways to obtain additional and/or alternative exemplary embodiments.
As the present features may be embodied in several forms without departing from the characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, unless otherwise specified, but rather should be considered broadly within its scope as defined in the appended claims, and therefore all changes and modifications that fall within the metes and bounds of the claims, or equivalents of such metes and bounds are therefore intended to be embraced by the appended claims.

## Claims

1. A wireless power transmitter comprising:
a body having a coil module therein, the coil module being configured to transmit power in a wireless manner;
a blowing module configured to cool the coil module by blowing a fluid past the coil; and
a guide module extending from the blowing module to an outside of the body such that the fluid from the blowing module is discharged outside of the body after cooling the coil module, the guide module having a shape that at least partially corresponds to an outer circumference of the coil module,
wherein the body includes a front case and a rear case,
wherein the guide module is formed on an inner surface of the front case, and
wherein the coil module includes a fixing plate fixed to the rear case, and a coil disposed on the fixing plate.

2. The wireless power transmitter of claim 1, wherein the front case includes protrusions configured to support an electronic device thereon in a spaced relationship from other portions of the front case during wireless power transfer.

3. The wireless power transmitter of claim 2, wherein the front case includes an outer guide configured to guide the fluid discharged from the blowing module through an opening of the front case to be discharged to a space between the electronic device and the outer surface of the front case.

4. The wireless power transmitter of claim 1, further comprising a circuit board having one or more devices configured to supply wireless power signals to the coil module.

5. The wireless power transmitter of claim 4, wherein the guide module includes a coil cooling portion configured to cool the coil module and a circuit board cooling portion configured to cool the circuit board.

6. The wireless power transmitter of claim 5, wherein the coil cooling portion is formed as a ring shape to enclose an outer circumference of the coil of the coil module, and
wherein one side of the coil cooling portion is in communication with the blowing module and another side of the coil cooling portion is in communication with the circuit board cooling portion.

7. The wireless power transmitter of claim 6, wherein the circuit board cooling portion includes a pair of ribs protruding from an inner surface of the body.

8. The wireless power transmitter of claim 5, further comprising a pad disposed between the circuit board and the circuit board cooling portion such that heat generated from the circuit board is transferred to the circuit board cooling portion.

9. The wireless power transmitter of claim 8, wherein the circuit board cooling portion includes a pair of ribs protruding from an inner surface of the body, and
wherein at least part of the pad is disposed between the ribs.

10. The wireless power transmitter of claim 1, wherein the blowing module includes a housing and a diaphragm configured to move up and down in the housing when supplied with a voltage.

11. The wireless power transmitter of claim 10, wherein the blowing module is formed to be rotatable at a prescribed angle with respect to the guide module so as to blow the fluid.

12. The wireless power transmitter of claim 1, wherein the body includes a display unit and a mounting unit configured to support an electronic device during wireless power transfer, and
wherein a size of the display unit is smaller than a size of the mounting unit.

13. The wireless power transmitter of claim 1, wherein the body includes a power socket configured to receive power externally from the body.

14. A wireless power transmitter comprising:
a body having a coil module located therein, the coil module being configured to wirelessly charge an electronic device disposed close thereto;
a case defining an appearance of the body;
a guide module arranged to surround at least a portion of the coil module, the guide module including an opening at the case;
a blowing module in communication with the guide module such that heat generated from the coil module is discharged to outside of the body through the opening by blowing fluid past the coil module; and
a circuit board having one or more devices configured to supply wireless power signals to the coil module,
wherein a portion of the guide module surrounding the coil module has a ring shape, and
wherein the guide module includes a coil cooling portion configured to cool the coil module, and a circuit board cooling portion configured to cool the circuit board.

15. The wireless power transmitter of claim 14, wherein a portion of the coil cooling portion contacting the coil module has a higher thermal conductivity than other portions of the coil cooling portion.

16. A system for wirelessly transferring power to an electronic device, the system comprising:
an electronic device configured to wirelessly receive power; and
a wireless power transmitter configured to wirelessly transmit power to the electronic device, the wireless power transmitter including:
a body having a coil module configured to transmit power to the electronic device wirelessly;
a blowing module configured to cool the coil module by blowing a fluid past the coil; and
a guide module extending from the blowing module to an outside of the body such that the fluid from the blowing module is discharged outside of the body after cooling the coil module,
wherein the body includes a front case and a rear case,
wherein the guide module is formed on an inner surface of the front case, and
wherein the coil module includes a fixing plate fixed to the rear case, and a coil disposed on the fixing plate.

17. The system according to claim 16, wherein the electronic device includes a receiving coil configured to receive power transmitted from the wireless power transmitter.

18. The system according to claim 16, wherein the wireless power transmitter includes a positioning unit configured to detect a position of the electronic device relative to the wireless power transmitter.