as) United States
`a2) Patent Application Publication co) Pub. No.: US 2011/0115429 Al
`
` TOIVOLAetal. (43) Pub. Date: May 19, 2011
`
`
`US 20110115429A1
`
`(54) WIRELESS CHARGING ADAPTER
`COMPATIBLE WITH WALL CHARGER AND
`WIRELESS CHARGING PLATE
`
`(75)
`
`Inventors:
`
`Timo Tapani TOIVOLA,Turku
`(FI); Juhani Valdemar KARL,
`Lieto (FI)
`
`(73) Assignee:
`
`Nokia Corporation, Espoo (FI)
`
`(52) US. CM. ceeccccscsssssssssssssssssessesessee 320/108: 307/104
`(57)
`ABSTRACT
`Example embodimentsare disclosed for wirelessly charging
`batteries of relatively small devices, such as wireless head-
`sets, using a relatively large wireless charging plate. In
`example embodiments of the invention, a high permeability
`magnetic field concentrator has a generally frusto-conical
`shape with a base at one end, tapering downto a pole at the
`opposite end. The concentrator is configured to concentrate
`magnetic flux at a lower flux density incident at the base from
`a proximate powertransmitting coil havingarelatively large
`(21) Appl. No.:
`12/618,276
`surface area in a wireless charger. The magnetic flux exits at
`a higher flux density at the pole end proximate to a power
`receiving coil having a relatively small surface area in a
`utilization device. The higher density magnetic flux couples
`with the powerreceiving coil, using contact-less electromag-
`netic induction. The wireless charger may be a charging plate
`and the utilization device may be a wireless headset. The
`magnetic field concentrator enables gathering sufficient
`powerbytherelatively small powerreceiving coil to charge
`the headset’s batteries within a reasonable time.
`
`(22)
`
`.
`Filed:
`
`Nov. 13, 2009
`
`Publication Classification
`
`(51)
`
`Int. Cl.
`H02J 7/00
`HOLF 27/42
`
`(2006.01)
`(2006.01)
`
`MAGNETIC FIELD
`CONCENTRATOR
`190
`BASE
`
`SMALL RECHARGEABLE DEVICE 200
`
`WIRELESS CHARGER100
`
`SPEAKER
`CONTROL20
`
`
`
`MICROPHONE
`CPU 60 S
`
`
`
`
`POWER
`
`
`CONTROL
`
`
`aTRANSCEIVER
`
`CIRCUITS
`
`
`
`106
`
`
`
`
`
`POWER
`
`
`FREQUENCY
`|
`RECTIFIER
`
`CHARGING
`DRIVER
`.
`Ss
`AND
`
`
`AND
`a INTERFACE
`IDENTIFICATION
`
`
`INTERFACE
`“
`CIRCUITS 105
`212
`
`
`
`
`104
`
`RAM 62
`
`PROM 64
`
`
`
`
`CHARGING
`
`IDENTIFICATION
`
`CIRCUITS 205
`
` BATTERY
`
`CONTROL
`
`CKTS 214
`
`
`
`POWER
`
`
`POWER
`TRANSMISSION
`COIL
`120
`
`RECEIVING
`COL
`220
`
`RECHARGEABLE
`BATTERY216
`
`1
`
`APPLE 1079
`Apple v. GUI
`IPR2021-00472
`
`1
`
`APPLE 1079
`Apple v. GUI
`IPR2021-00472
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 1 of 23
`
`US 2011/0115429 Al
`
`$02SLINDUID
`
`ANSLIVE
`
`SNIDUVHO
`
`
`
`NOLLVOIAILNAGI
`SdOVANSLNI
`
`YaiLLO3y
`
`aNvY
`
`ole
`
`YaAV1OVooVY
`MSAOSNVELon79WOUd
`
`L
`
`
`
`002SDIASOFISVSONVHOSdTIVANS06134sva00)HAOUVHSSSaTSUIM
`ee96}anc
`
`
`
`
`
`SNOHdOUSIN
`
`Yanvads02TOYNLNOD
`
`g09Ndd
`
`hywaM0d
`
`YOLVULNAQNOD
`
`
`
`O1aldSILANDVALaa)
`
`YaMOd
`
`
`
`ADNANOAYS
`
`aaAldd
`
`CNV
`
`JOVAdALNI
`
`vOl
`
`ONIDUVHO
`
`NOLLVOISLLNaGI
`
`SOLSLINDYIOD
`
`JOULNOD
`
`SLINDUID
`
`901
`
`
`
`
`
`TTEVADNVHOAYYdaMOdYaMOd
`
`
`
`
`
`912AMALLVEONIAIZOSYNOISSINSNVYL
`
`W039W039
`
`0c021
`
`201
`
`JONLNOD
`
`
`
`pleSLH9wAMOd
`
`S39uNOs
`
`2
`
`
`
`
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 2 of 23
`
`US 2011/0115429 Al
`
`Yad VeSls
`
`
`
`
`
` ff00)YADYVHOSSATSYIM
`
`YaMOd
`
`NOISSIAISNVYL
`
`021fWOOWNNALNY
`
`YSMOd
`
`AONANDSYS
`
`yaAlad
`
`aNy
`
`JOVANALNI
`
`y0l
`
`TOULNOD
`
`901SLINDHID
`
`ONIDYVHO
`
`NOILVOIALLNAGI
`
`SOLSLINDUID
`
`
`
`dOuNOSYAMOd
`
`OL
`
`22)GUVOEONIMIMGSLNIdS.YIONVHO
`
`
`
`
`
`
`
`
`
`3
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 3 of 23
`
`US 2011/0115429 Al
`
`
`
`
`
`G02SLINDUIDz12
`NOILVOIMLLNAG!
`ONIDYVHOONY
`
`*SOVANSLNI
`ualdiLogy
`
`Adallva
`
`OULNOD
`
`pleSLyo
`
`912AMALIVEaaVaOuvVHoda
`
`SNOHdONDIN
`
`eanvads02TOALNOD
`
`YaAVOVA29VY
`
`
`
`NSAIDSNVAL
`
`v9WOdd
`
`09VWNNALNY
`
`(MIMGaddvVuMm)
`
`k022
`
`My¢09Ndd
`
`ONIAIGOIYMAMOd
`
`
`
`
`
` A002SDIAKGFIGVSOUVHOSdTIVAS
`
`déSls
`
`
`
`
`
`é¢éGUVOdONTMIMCILNIdd
`
`4
`
`
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 4 of 23
`
`US 2011/0115429 Al
`
`yawVads02TOULNOD A002ADIAAC
` MAAV1OVz9WWYWO9VNNSLNY
`
`
`FTGVIONVHOIYTIVWS92‘Sls
`
`
`
`G0¢SLINDYID
`
`NOWLWOLINAOLee
`
`AYALLVE
`
`TONLNOD
`
`bleSLHO
`
`d1Va9uVHOsY
`
`OléAMALLVE
`
`
`
`
`
`272GUVOEONIMIMGALNINd
`
`ONIDUVHD|ONY
`
`YsldLLOay
`
`SdDVANSLNI
`
`ANOHdOUOIN
`
`xQ09Ndd
`
`YsAIZOSNVaL
`
`
`
`p9WOdd022
`
`
`
`ONIAIZOIYWAMOd
`
`(ANIMGSLNIMd)
`
`5
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 5 of 23
`
`US 2011/0115429 Al
`
`JILSNOVIN
`
`@al4
`
`OSL
`
`
`
`Wd
`
`02L
`
`VeSia
`NOISSIASNVAL|_——_4Mod
`ONTMIMCALNIUd
`
`
`
`
`S.AaDYVHO
`
`ezGHVO"d
`
`6
`
`

`

`=OLLANOVIN=GSLVYLNIONOD
`
`aw
`
`Soe<q¢“Ola5Rx
`
`US 2011/0115429 Al
`
`OS}
`
`aNOISSIWSNVYL=a——_Mod
`
`«ONIMIMCALNId
`aS.MAONVHOS<0z13109
`aa>,961—S\(a=asva=sKNg06hfstog5MOLVYLNSONODaaldZS}zqiald
` aialswe
`
`zzGHvOd
`
`7
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 7 of 23
`
`US 2011/0115429 Al
`
`|TSe¥6Leria——CS
`
`
`
`YOLVELNIDNOD
`
`qals
`
`061
`
`uaMOd
`
`ONIAISO3Y
`
`1109
`
`(GaddvuM)
`
`022
`
`00¢SDIAIC
`
`JIGVSONVHOSYTIVNS
`
`Je“Sls
`
`NOISSINSNVYL
`
`SILANOVIN
`
`qiald
`
`0S
`
`S.YaDYVHD
`
`ONIMIMCaLNId
`
`
`
`
`
`celGUVOE
`
`WO3
`
`02)
`
`8
`
`
`

`

`US 2011/0115429 Al
`
`
`
`JWANOVIN
`
`q1ald
`
`OS!
`
`aw
`
`amd35Z002SdIASCeJISVAONVHOAYTVSa¢c)|4=2Rx
`11092YOLVYLNSONODONIAIEDSY<qials
`
`i0225(G3.LNIdd)s06}
`
`=J——_4aMOdRSem>=961=
`
`5asva2wlCo(—eS
`
`
`
`NIMIMCALNIMd:S.NADNWHD)3Oz!:1109?NOISSINSNVUL
`
`zz}GHYVOd
`
`9
`
`
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 9 of 23
`
`US 2011/0115429 Al
`
`961PSK||/FAasvg
`
`aay
`
`TWOIONOLest
`
`YOLVHLNIONODfJUNLYadV
`061861
`
`GALVYLNSDNOD
`
`JILINOVIN
`
`anal
`
`
`NOISSIWSNVYL1,——_83Mod5|LopPe~
`
`
`
`aisldun
`
`0S}
`
`S.MIOUVHO
`
`
`
`ONIMIMGALNINd
`
`zzGUWOS
`
`109
`
`Oz!
`
`10
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 10 of 23
`
`US 2011/0115429 Al
`
`YOLVHLNAINOD
`
`061
`
`
`
`YaMOd
`
`002SDIAZa
`
`SILANOVAos
`
`Wala
`
`0S)
`
`orf|LSAAe
`Asvea/2tLOl~ee1\022
`TWdlOYdOLONIAIOSY
`
`ey(Gaddvei)
`eisnOSoOSWS
`wisieitSS
`
`FTAVAaONVHOSYTIVWS
`1,——_4aMod
`de‘Sls
`
`
`
`11
`
`S:aDYaVHD
`
`
`
`ONIUIMCS.LNIdd
`
`2bdUYvOa
`
`NOISSIASNVaL
`
`109
`
`OZ}
`
`11
`
`
`
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 11 of 23
`
`US 2011/0115429 Al
`
`YOLVULNSINOD
`
`
`
`aialdzzaldOLSNOVIN
`
`dsva
`
`961
`
`OGL
`
`6b3aind
`
`
`
`12
`
`<—
`
`4aMOd
`
`NOISSINSNVal
`
`10d
`
`02}
`
`MSMOd
`
`QNIAIZOSY
`
`09
`
`(daddVuM)
`
`JIAVIOUVHOTYTIWWSVV©)a
`“>J0IAaa.
`
`
`
`12
`
`
`

`

`i}i
`
`=a&avSls
`
`
`==x\Nan=a)S=—|L—_S2==&z6}5qaine$Q1ald
`—Y=“aeseS}
`
`
`
`
`DILANOVIN=00z39IAga&J1IGVSOUVHOTYTIVINS
`
`z51a0z2022
`NSL6L
`
`13
`
`
`
`-251<—~404avails
`
`r61YOLVULNSONOD
`
`US 2011/0115429 Al
`
`061
`
`13
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 13 of 23
`
`US 2011/0115429 Al
`
`waMOd
`
`NIAISOIY
`
`1109
`
`(daddvum)
`
`ad
`
`eS)
`
`
`
`
`
`cGb
`
`022
`
`iS]
`
`14
`
`410dMOLVYLNADNOD
`
`qTald
`
`¥6106!
`
`UvSIs
`
`
`
`JEVAONVHISYTIVAS
`
`002SDIARG
`
`14
`
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 14 of 23
`
`US 2011/0115429 Al
`
`YOLVYLNAONOD76h022
`
`aiid‘(GS.L.NIMd)
`
`
`
`
`qaind109
`
`C13/4DILANOVONIATSOSY
`
`
`
`
`
`061
`
`~_——
`
`YaMOd
`
`NOISSINSNVUL
`
`W039
`
`02}
`
`15
`
`usaMOd
`
`
`
`TISGVAONVHOSYTVSav)ia
`002S9IASC"
`
`15
`
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 15 of 23
`
`US 2011/0115429 Al
`
`
`
`(1414OLLANSV
`
`261Neydaind
`octest
`
`261
`
`LHLWAAL
`
`
`
`
`
`zs+<—404ovals
`
`+6)YOLWULNSONOO
`
`061
`
`Av‘Sis
`
`
`
`A1eaVS9uVHOSYTIVINS
`
`002SDIAIC
`
`16
`
`16
`
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 16 of 23
`
`US 2011/0115429 Al
`
`YaMOd
`
`ONIAIOSY
`
`109
`
`
`
`(ONIMIMGSLNId
`
`)
`
` 022
`
`eS
`
`éGl
`
`dv‘Sls
`
`
`
`J1aVS9NVHOSYTIVNS
`
`002JDIASC
`
`8S)
`
`17
`
`42710
`YOLVALNIINOD
`
`v6
`
`ald
`
`061
`
`17
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 17 of 23
`
`US 2011/0115429 Al
`
`
`
`C7314OILANOVW
`
`3aino
`
`26)
`
`ESI
`
`
`
`7S)<—~0aavails
`
`
`
`\sastessssnnepeasensnsnansastevasasneepmanennurbeenunnmanueassisssau.esnnsuufessuesense{srmsursnrnnanee.
`
`liSSThSrioo:\022
`
`
`esl
`
`OPDla
`
`
`
`31aVaONVHOTYTIVWS
`
`00z391Aaa
`
`ZS)
`
`18
`
`6. YOLVYLNSONOD
`
`06}
`
`18
`
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 18 of 23
`
`US 2011/0115429 Al
`
`
`
`YOLVYLNADNOD
`
`06}
`
`q7al:\
`
`
`
`
`
`avrGO}SLINOWIO
`
`pol
`
`YaMOd
`
`JONNOS
`
`zOL
`
`AONANDAUS
`
`
`
`aaArudQNIDUWHO
`
`NOLLVOI4ILNACI
`
`uaONVHD=«10d901uaOUVHO
`
`
`NNG6L1109v6lS611109
`
`
`
`
`
`
`00)YADUVHDSSATSMIM
`
`yaMOd
`
`YsONVHO
`
`
`
`TOPSLINDUIO
`
`YaMOd
`
`JOULNOD
`
`S.LINDHID
`
`VS‘Sls
`
`19
`
`19
`
`
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 19 of 23
`
`US 2011/0115429 Al
`
`
`
`YaDaVHO410dS611109
`
`S6L1109véLYaDYVHD
`
`
`
`
`YOLVALNAONOD
`
`061
`
`aval\
`
`LOLSLINDUID
`
`20
`
`YaMOd
`
`JOUNOS
`
`COL
`
`Ys9uYVHO
`
`gS‘Sls
`
`20
`
`
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 20 of 23
`
`US 2011/0115429 Al
`
`961\asva
`
`JLLANSVN
`
`061
`
`YOLVALNAINOD
`qalsvel
`
`q1ald
`
`OLLANOVW
`
`q1sld
`
`OSL
`
`dsLVaLNSONOD US‘Sls
`YaDUVHOYaSYVHO
`S6L1109S6L109
`
`LOLSLINDYIDaYaOUVHD
`
`21
`
`21
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 21 of 23
`
`US 2011/0115429 Al
`
`YSMOd
`
`ONIAIZOFa
`
`“Nso0za01Ag
`
`
`
`JTEVAOUVHOSYTIVNS
`
`ds‘Sid
`
`0cz
`
`
`
`1109QalaOLLSNDVN
`
`S6L109
`
`bP310d
`
`asva
`
`961
`
`YOLVYLNADNOD
`
`061
`
`aqiald\
`
`JdINS
`
`c6l
`
`S6L1109
`
`
`
`YSONVHOLObSLINDYID
`
`YaDNVHO
`
`aaMOd
`
`39YuNOS
`
`col
`
`22
`
`22
`
`
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 22 of 23
`
`US 2011/0115429 Al
`
`YaAISSNVeL
`
`2b
`
`hy909Ndd
`
`JOULNOD
`
`
`
`
`$61109:\YaMOd
`ANOHdONSING0éSLINDUIDZz
`
`SELStiog10)SLINOUIDYaOUVHOy6l/\10d
`
`
`
`Mayvads02TONLNOS30V4NSLNINOILVOIAILNAG
`
`
`YaAV1OVooAVYANSLIVE
`rypoWOUdplzSLID
`
`/\OeAMSLLVE
`(webJ18VseouVHosY
`08SFOIACADYVHDSSATAYIMYSHLOYOSNOHd
`061YOLVELNSONOODC714YIONVHO=:HDHD3G.fc)i-]
`
`ONIDYVHDONY026
`
`.
`
`gounos
`
`éOL
`
`YaIsLLOSyWOd
`
`HaMOd
`
`ONIAIOSe
`
`23
`
`
`
`23
`
`
`
`
`

`

`Patent Application Publication
`
`May 19, 2011 Sheet 23 of 23
`
`US 2011/0115429 Al
`
`ASV
`
`961
`
`YOLVELINADNOD
`
`061
`
`anal\
`
`waMOd
`
`ONIAIZOSY
`
`1109
`
`09s
`
`1aMO0$z61
`
`
`
`azzQ7aldDILSNOVW
`
`gaino
`
`“Nsooz301A
`
`
`
`aTaVASNVHOsdTIVAS
`
`ds‘Sis
`
`
`
`0sS611109S61109ogg
`
`uIONVHNSOUWHO
`
`ONISNOHSYVHOONISNOH
`
`24
`
`YdDYVHD
`
`
`
`LO}SLINDUID
`
`24
`
`
`
`

`

`US 2011/0115429 Al
`
`May 19, 2011
`
`WIRELESS CHARGING ADAPTER
`COMPATIBLE WITH WALL CHARGER AND
`WIRELESS CHARGING PLATE
`
`charging plate, presents too small an area to gather sufficient
`powerto charge the headset’s batteries within a reasonable
`time.
`
`FIELD
`
`SUMMARY
`
`[0001] The technical field relates to wireless charging of
`batteries in portable devices. Moreparticularly, the technical
`field relates to techniques for wirelessly charging batteries of
`relatively small rechargeable devices, such as wireless head-
`sets.
`
`BACKGROUND
`
`[0005] Example embodimentsare disclosed for wirelessly
`charging batteries of relatively small rechargeable devices,
`such as wireless headsets, using a relatively large wireless
`charging plate. In example embodiments of the invention, a
`high permeability magnetic field concentrator has an opti-
`mized shape to concentrate the magnetic field. Non-limiting
`examples include a generally frusto-conical shape and a gen-
`erally toroidal shape. An example frusto-conical shape for a
`magnetic field concentrator has a base at one end, tapering
`down to a pole at the opposite end. The example frusto-
`[0002] Rechargeable batteries in cellular phones and other
`conical shaped concentrator is configured to concentrate an
`portable communication devices, such as NiCd, nickel-metal
`applied magnetic flux at a lower flux density incidentat the
`hydride (NiMH), Lithium-ion, and Lithium-Polymerbatter-
`base from a proximate power transmitting coil havingarela-
`ies, can be recharged with householdalternating current (AC)
`tively large surface area in a wireless charger. The magnetic
`power coupled through a voltage reduction transformer, an
`flux exits at a higher flux density at the pole end proximate to
`a powerreceiving coil havingarelatively small surface area in
`alternating-to-direct current converter, and appropriate bat-
`autilization device. The higher density magnetic flux couples
`tery monitoring and charging circuits. They can also be
`with the powerreceiving coil, using contact-less electromag-
`recharged with a 12-volt cigarette lighter socket provided in
`netic induction. The wireless charger may be a charging plate
`an automobile coupled through a DC voltage reduction cir-
`and the utilization device may be a small rechargeable device,
`cuit and appropriate battery monitoring and chargingcircuits.
`such as wireless headset. The magnetic field concentrator
`However, in both cases, the portable communication device
`enables gathering sufficient power by the relatively small
`mustbe plugged into a household AC powersource such as a
`power receiving coil
`to charge the small
`rechargeable
`wall charger or into the automobile powersource, limiting the
`device’s batteries within a reasonable time.
`mobility of the communication device.
`[0003] Recently, wireless charging has become available
`for rechargeable batteries in cellular phones and other por-
`table communication devices, using contact-less electromag-
`netic induction. A powersource circuit in a wireless charging
`device drives a resonant frequencyoscillator that produces a
`source alternating current in a frequency range between 50
`kHz and 20 MHz, whichis driven through a transmitting coil
`in the charging device. The alternating magnetic field pro-
`duced by the transmitting coil inductively couples with a
`corresponding receiving coil in the cellular phone or other
`portable communication device, thereby producing a corre-
`sponding inducedalternating currentthat drives an oscillator
`at its resonant frequency in the range between 50 kHz and 20
`MHzto produce an output AC voltage. A conversion circuit in
`the cellular phone or other portable communication devices,
`uses a transformerto adjust the output AC voltage, an alter-
`nating-to-direct current converter, and appropriate battery
`monitoring and charging circuits to produce an appropriate
`DC charging voltage for the rechargeable battery. The wire-
`less charger is generally shaped as a charging plate and the
`cell phone or other rechargeable device is laid on the plate
`during the charging operation.
`[0004] With the advent of Bluetooth technology, wireless
`headsets containing an earpiece and microphone may be
`worn by the user, which use the Bluetooth wireless connec-
`tion to the user’s cell phone to enable conducting telephone
`conversations. The headpiece requires its own battery forits
`operation and rechargeable batteries are economical to avoid
`frequent replacement. However, wireless chargers that are in
`the form of a charging plate designed for recharging cell
`phonebatteries, have a charging coil surface area muchlarger
`than the overall size of a headset. The relatively small foot-
`print of a headset when positioned on the charging coil of a
`
`[0006] Anexampletoroidal shape for a magneticfield con-
`centrator has a generally circular body with a base and an
`upper surface, surrounding a generally circular aperture. The
`example toroidal shaped concentrator is configured to con-
`centrate an applied magnetic flux at a lower flux density
`incident at the base from a proximate powertransmitting coil
`having a relatively large surface area in a wireless charger.
`The magnetic flux exits at a higher flux density at the upper
`surface proximate to a powerreceiving coil having a rela-
`tively small surface area in a utilization device. The higher
`density magnetic flux couples with the powerreceiving coil,
`using contact-less electromagnetic induction.
`[0007] A variety of small
`rechargeable devices use
`rechargeable batteries that may be recharged by embodiments
`of the invention, including wireless headsets, hearing aids,
`cardiac pacemakers, small medical devices such as a pill-
`sized radio and camera for gastrointestinal diagnosis, small
`dental devices such as an ultraviolet light source for curing
`polymerdentalfillings, wireless mouse, wearable ubiquitous
`computing devices, small surveillance cameras, illuminated
`jewelry, battery-operated toys, andthelike.
`[0008]
`In example embodiments of the frusto-conical
`shaped concentrator, charger coils may be wrapped around
`the pole endof the concentrator, the coils being substantially
`concentric with the frusto-conical shape. The coils are con-
`figured to conduct alternating current in a frequency range
`between 50 kHz and 20 MHzto producean alternating mag-
`netic field to inductively couple with the proximate receiving
`coil at the pole end of the concentrator, using contact-less
`electromagnetic induction. The magnetic field concentrator
`enables gathering sufficient power by the relatively small
`power receiving coil
`to charge the small
`rechargeable
`device’s batteries within a reasonable time.
`
`[0009] The high permeability magnetic field concentrator
`has an optimized shape to concentrate the magnetic field.
`
`25
`
`25
`
`

`

`US 2011/0115429 Al
`
`May 19, 2011
`
`Non-limiting examples of the magnetic field concentrator
`include a generally frusto-conical shape and a generally tor-
`oidal shape, but other shapes may be employed to concentrate
`the magnetic field to enable small rechargeable devices hav-
`ing a small area to gather sufficient power to charge the
`device’s batteries within a reasonable time.
`
`trator and includes an upward extending wall that forms a
`flat-bottomed cavity with the base of the guide. The power
`receiving coil is wrapped around the guide to reduce fringe
`fields and urge the applied magneticfield in the powerreceiv-
`ing coil into more nearly parallel paths.
`[0017] Example embodimentsofthe invention may employ
`resonant magnetic coupling, considered a subset of inductive
`coupling. In resonant magnetic coupling,a first alternating
`current in a resonant receiving coil a self-resonantcircuit in a
`utilization device, is tuned to resonate at substantially the
`same resonant frequency as a resonant transmitting coil in a
`self-resonant circuit of a wireless charger,
`the resonant
`receiving coil operating as a magnetically coupled resonator
`with the resonant transmitting coil. The separation distance
`between the two coils may be several times larger than the
`geometric sizes of the coils. In example embodiments of the
`invention, the resonant receiving coil is strongly coupled to
`the resonanttransmitting coil when the resonant transmitting
`coil is driven at the resonant frequency commonto both coils,
`even when a separation distance between the two coils is
`several times larger than geometric sizes ofthe coils.
`
`DESCRIPTION OF THE FIGURES
`
`In example embodiments of the invention, a high
`[0010]
`permeability magnetic field guide within the small recharge-
`able device, directs the magnetic field concentrated by the
`high permeability magnetic field concentrator into the power
`receiving coil. The high permeability magnetic field guide
`reduces fringe fields and urges the concentrated magnetic
`field in the power receiving coil into more nearly parallel
`paths in the small rechargeable device. The magnetic field
`guide has an optimal shapeto direct the magnetic field of the
`concentrator into the power receiving coil. Non-limiting
`examples include a generally coin-shaped magnetic field
`guide with the base of the guide juxtaposed with the concen-
`trator. The high permeability magnetic field guide directs the
`concentrated magnetic flux incidentat the flat bottomed base
`of the guide to reducefringe fields and urge the concentrated
`magnetic field in the power receiving coil into more nearly
`parallel paths.
`[0011]
`In example embodimentsof the invention, an alter-
`FIG. 1 illustrates an example embodiment for a
`[0018]
`nate example embodiment may have two coin-shaped mag-
`wireless charging arrangement for a small rechargeable
`netic field guides between which is sandwichedthe printed
`device’s battery, such as in a wireless headset, employing an
`wire receiving coil, the guide directing the magneticfield into
`example high permeability magnetic field concentrator to
`the printed wire coil to enhance the inductive coupling of the
`match a proximate powertransmitting coil having a relatively
`powerreceiving printed wire coil.
`large surface area in a wireless charger, with a proximate
`[0012] Anexample ring-shaped magneticfield guide witha
`powerreceiving coil having a relatively small surface area in
`base, and around the ring is wrapped the powerreceiving coil
`a small rechargeable device, such as a wireless headset.
`so as to be coplanar with the base and juxtaposed with the
`[0019]
`FIG. 2A illustrates an example embodimentfor a
`concentrator. The high permeability magnetic field guide
`wireless charger.
`directs the concentrated magnetic flux incident at the base of
`[0020]
`FIG. 2B illustrates an example embodimentfor a
`the guide to reduce fringe fields and urge the concentrated
`small rechargeable device with a wrapped wirecoil.
`magnetic field in the power receiving coil into more nearly
`[0021]
`FIG. 2C illustrates an example embodimentfor a
`parallel paths.
`small rechargeable device with a printed wire coil.
`the
`[0013]
`In example embodiments of the invention,
`[0022]
`FIG. 3A illustrates an example embodimentfor a
`charger coil produces an alternating magneticfield below the
`magnetic field produced by powertransmitting coil having a
`base of the concentrator, to inductively couple with a proxi-
`relatively large surface area in a wireless charger.
`mate powerreceiving coil of a device such as a cell phone,
`[0023]
`FIG. 3B illustrates an example embodimentfor a
`positioned below the base of the concentrator, using contact-
`magnetic field concentrated by a high permeability magnetic
`less electromagnetic induction.
`field concentrator positioned above a powertransmitting coil
`having a relatively large surface area in a wireless charger.
`[0014]
`Inexample embodiments ofthe invention, a housing
`covers the concentrator from the base toward the top and
`[0024]
`FIG. 3C illustrates an example embodimentfor a
`formsa socket cavity at the top, configured to acceptinsertion
`magnetic field concentrated by a high permeability magnetic
`of the powerreceiving coil of a small rechargeable device.
`field concentrator and directed into a power receiving
`wrapped wire coil having a relatively small surface area in a
`[0015]
`Inexample embodimentsof the invention, the mag-
`small rechargeable device.
`netic field concentrator may include miniaturized charger
`[0025]
`FIG. 3D illustrates an example embodimentfor a
`circuits on a printed wiring board, to perform the functions of
`magnetic field concentrated by a high permeability magnetic
`the circuits that drive the charger coils wrapped around the
`field concentrator and directed into a powerreceiving printed
`pole end of the concentrator. The power source may be a wall
`wire coil having a relatively small surface area in a small
`charger, mains, or a battery pack, to provide the powerto the
`rechargeable device.
`miniaturized chargercircuits.
`[0026]
`FIG. 3E illustrates another example embodimentfor
`[0016]
`In example embodiments of the invention, a wire-
`a magnetic field concentrated by a toroidal shaped high per-
`less rechargeable headset includes an ear piece speaker; a
`meability magnetic field concentrator positioned above a
`wireless transceiver coupled to the ear piece; a rechargeable
`powertransmitting coil having a relatively large surface area
`battery coupled to the transceiver and ear piece; a wireless
`in a wireless charger.
`powerreceiving coil coupledto the rechargeable battery; and
`[0027]
`FIG. 3F illustrates the example embodimentfor a
`a high permeability magneticfield guide configured to direct
`toroidal shaped high permeability magnetic field concentra-
`an applied magnetic field from a high permeability magnetic
`field concentrator into the powerreceiving coil ofthe headset.
`tor, with the concentrated magnetic field and directed into a
`
`The magnetic field guide is generally ring-shaped withaflat powerreceiving wrapped wire coil havingarelatively small
`bottomed base that is juxtaposed with a pole of the concen-
`surface area in a small rechargeable device.
`
`26
`
`26
`
`

`

`US 2011/0115429 Al
`
`May 19, 2011
`
`FIG. 4A illustrates an example embodimentfor a
`[0028]
`high permeability magnetic field guide for a wrapped wire
`coil, which helps direct a magnetic field concentrated by a
`high permeability magnetic field concentrator into a power
`receiving wrapped wire coil having a relatively small surface
`area in a small rechargeable device.
`[0029]
`FIG.4Billustrates the example embodimentof FIG.
`4A, showing how the magnetic field guide directs the mag-
`netic field into the wrapped wire coil to enhance the inductive
`coupling of the power receiving wrapped wire coil.
`[0030]
`FIG. 4C illustrates the example embodimentof FIG.
`4A, showing how the absence of the magnetic field guide
`causes a reduction in the magnetic field coupling the power
`receiving wrapped wire coil.
`[0031]
`FIG. 4D illustrates an example embodimentfor a
`coin-shaped magnetic field high permeability magneticfield
`guide for a printed wire coil, which helps direct a magnetic
`field concentrated by a high permeability magneticfield con-
`centrator into a power receiving printed wire coil having a
`relatively small surface area in a small rechargeable device.
`[0032]
`FIG. 4E illustrates the example embodiment of FIG.
`4D, showing how the coin-shaped magnetic field magnetic
`field guide directs the magnetic field into the printed wire coil
`to enhance the inductive coupling of the power receiving
`printed wire coil.
`[0033]
`FIG.4F illustrates the example embodimentof FIG.
`4D, showing how the absence of the magnetic field guide
`causes a reduction in the magnetic field coupling the power
`receiving printed wirecoil.
`[0034]
`FIG. 4G illustrates an alternate example embodi-
`ment,
`showing two coin-shaped magnetic field guides
`between which is sandwichedthe printed wire receiving coil,
`the guide directing the magnetic field into the printed wire
`coil to enhance the inductive coupling of the powerreceiving
`printed wire coil.
`[0035]
`FIG. 5A illustrates an example embodimentfor a
`wireless charging arrangement wherein chargercoils are dis-
`posed aroundthe pole end of the concentrator, configured to
`produce an alternating magnetic field to inductively couple
`with the proximate receiving coil, using contact-less electro-
`magnetic induction.
`[0036]
`FIG. 5Billustrates an example embodimentfor the
`magnetic field concentrator with miniaturized charger cir-
`cuits.
`
`FIG. 5C illustrates an example embodimentfor a
`[0037]
`magnetic field produced by the charger coil of FIG. 5A.
`[0038]
`FIG. 5D illustrates an example embodimentfor a
`wireless charging arrangement with the charger coil charging
`the small rechargeable device, with the wireless charging
`circuits of FIG. 5A integrated into the concentratorstructure.
`[0039]
`FIG. 5E illustrates an example embodiment for
`charger coil producing an alternating magnetic field to induc-
`tively couple with a proximate power receiving coil of a
`device such as a cell phone, positioned below the base, using
`contact-less electromagnetic induction.
`[0040]
`FIG. 5F illustrates an example embodimentfor a
`housing covering the conical surface ofthe concentrator from
`the base toward the pole and forming a socket cavity above the
`pole configured to accept insertion ofthe powerreceiving coil
`of the small rechargeable device.
`DISCUSSION OF EXAMPLE EMBODIMENTS
`OF THE INVENTION
`
`FIG. 1 illustrates an example embodiment for a
`[0041]
`wireless charging arrangement for a small rechargeable
`
`device’s battery, such as in a wireless headset, employing an
`example high permeability magnetic field concentrator to
`match a proximate powertransmitting coil having a relatively
`large surface area in a wireless charger, with a proximate
`powerreceiving coil having a relatively small surface area in
`a small rechargeable device, such as a wireless headset.
`[0042]
`FIG. 1 illustrates an example embodiment for a
`wireless charging arrangementfor a battery 216, employing a
`high permeability magnetic field concentrator 190 to match a
`proximate power transmitting coil 120 having a relatively
`large surface area in a wireless charger 100, with a proximate
`power receiving coil 220 having a relatively small surface
`area in a utilization device, such as a small rechargeable
`device 200. Permeability is the degree to which a material
`responds to an applied magnetic field and becomes magne-
`tized. Materials that exhibit a high magnetic permeability are
`typically composed of ferromagnetic metals such as iron,
`cobalt, and/or nickel or compoundssuchasferrite.
`[0043]
`In an example embodiment, a powersource circuit
`102 in the wireless charging device 100 drives a powerfre-
`quencydriver and interface 104 that produces a sourcealter-
`nating current in a frequency range between 50 kHz and 20
`MHz, which will provide energy to recharge the rechargeable
`batteries 216. The power control circuits 106 control the
`powerlevel output by the charger 100. The charging identi-
`fication circuits 105 identify the target current and voltage to
`be applied to each type of rechargeable battery 216.
`[0044] The transmit coil 120 may be anysuitable shape
`such asprinted coil, multilayer coils, wired antennacoils, and
`the like. FIG. 2A illustrates an example embodiment for a
`wireless charger with the power transmission antenna coil
`120 being a printed wiring coil on a printed wiring board 122
`shownasa relatively large charging plate in the side view of
`FIG.3A.In alternate embodiments, a separate printed wiring
`board 122 may be omitted and the coil 120 may incorporated
`into the body ofthe printed wiring board or it may be glued to
`a plastic substrate forming the chargingplate.
`transmission
`[0045] The relatively large area power
`antenna coil 120 produces an alternating magnetic field 150
`shownin FIG. 3A. The current carrying wires of the power
`transmission antenna coil 120 generate magnetic field lines
`150 that form concentric circles around the wires 120. FIG.
`
`3B illustrates the effect on the magnetic field 150 by placing
`the high permeability magnetic field concentrator 190 proxi-
`mate to the powertransmitting coil 120. In example embodi-
`ments of the invention, a high permeability magnetic field
`concentrator in an optimized shape to concentrate the mag-
`netic field. Non-limiting examples include a generallyfrusto-
`conical shape and a generally toroidal shape.
`[0046] An example frusto-conical shape for a magnetic
`field concentrator 190 has a generally frusto-conical shape
`with a base 196 at one end, tapering downto a pole 194at the
`opposite end. The concentrator 190 is configured to concen-
`trate magnetic flux 150 at a lower flux density incident at the
`base 196 produced by the proximate powertransmitting coil
`120 in the wireless charger 100. The magnetic flux density
`through a surface is proportional to the number of magnetic
`field lines that pass through the surface. The magnetic flux
`152 exits at a higher flux density at the pole end 194 proximate
`to the power receiving coil 220, as shown in FIG. 3C. The
`higher density magnetic flux 152 couples with the power
`receiving coil 220, using contact-less electromagnetic induc-
`tion. The magnetic field concentrator 190 enables gathering
`
`27
`
`27
`
`

`

`US 2011/0115429 Al
`
`May 19, 2011
`
`sufficient powerby the relatively small powerreceiving coil
`220 to charge the small rechargeable device’s batteries 216
`within a reasonable time.
`
`the voltage induced in the power receiving coil 220 will no
`longer match the wave-shape of the voltage powering the
`power transmitting coil 120. If this happens, less than full
`power maybetransferred to the powerreceiving coil 220.
`[0047] Anexample toroidal shape for a magneticfield con-
`[0050]
`FIG. 2B illustrates an example embodimentfor a
`centrator 190' in FIG. 3E hasa generally circular body with a
`wirelessly charged small rechargeable device. The power
`base 196 and an uppersurface, surrounding a generally cir-
`receiving antenna coil 220 may be a wrapped wire coil as
`cular aperture 198. The example toroidal shaped concentrator
`shown in FIG. 2B and FIG. 3C or it may be a printed circuit
`is configured to concentrate an applied magnetic flux 150 at a
`220' as shown in FIG. 2C and FIG.3D. The printed wiring coil
`lowerflux density incidentat the base 196 from a proximate
`220' may be formed ona printed wiring board 222 shown in
`powertransmitting coil 120 havingarelatively large surface
`the side view in FIG. 3C. The printed wiring coil 220' may be
`area in a wireless charger. The magnetic flux exits at a higher
`formed onaprinted wiring board that may be a separate board
`flux density 152 at the upper surface proximate to a power
`from that which holds the remaining electronics. In alternate
`receiving coil 220 shownin FIG.3F, havingarelatively small
`embodiments, a separate printed wiring board 222 may be
`surface area in a utilization device. The higher density mag-
`omitted and the printed wire coil 220' may be incorporated
`netic flux couples with the power receiving coil, using con-
`into the body ofthe printed wiring board or it may be glued to
`tact-less electromagnetic induction.
`a plastic substrate in the small rechargeable device 200. The
`[0048] Magnetic flux always forms a closed loop, but the
`wireless powercoils 120 and 220 are planar coils. The wire-
`path of the loop depends on the magnetic permeability of the
`less power coils 120 and 220 are shownjuxtaposed in FIG. 3C
`surrounding materials. Magnetic flux is concentrated along
`and FIG. 3D, coplanarto enable efficient inductive coupling
`the path of highest magnetic