`
`
`as) United States
`
`
`
`
`
`
`
`
`a2) Patent Application Publication 0) Pub. No.: US 2006/0061323 Al
`
`
`
`
`
`
`
`
` Chengetal. (43) Pub. Date: Mar. 23, 2006
`
`
`
`US 20060061323A1
`
`
`
`
`
`
`
`
`
`(52) US. Cd. ce ceceecccceeecsseecessnsecsnseeceneeecnnseesnnnseesnnsees 320/108
`
`
`
`
`
`(57)
`
`
`
`ABSTRACT
`
`
`
`(76)
`
`(30)
`
`
`
`
`(54) CONTACT-LESS POWER TRANSFER
`
`
`
`
`
`
`
`Inventors: Lily Ka-Lai Cheng, London (GB);
`
`
`
`
`James Westwood Hay, Cambridge
`
`
`
`
`(GB); Pilgrim Giles William Beart,
`
`
`Cambridge (GB)
`
`
`Correspondence Address:
`
`
`
`STITES & HARBISON PLLC
`
`
`
`1199 NORTH FAIRFAX STREET
`SUITE 900
`
`
`
`ALEXANDRIA, VA 22314 (US)
`
`
`
`
`(21) Appl. No.:
`
`
`
`(22) PCT Filed:
`
`
`
`(86) PCT No.:
`
`
`
`
`
`
`10/532,977
`
`
`Oct. 28, 2003
`
`
`
`PCT/GB03/04654
`
`
`
`Foreign Application Priority Data
`
`
`(GB) w.eeccesesssesseseenneeneeenes 0225013.2
`
`
`
`
`
`
`
`Oct. 28, 2002
`
`Publication Classification
`
`
`
`(51)
`
`
`
`
`Int. Cl.
`
`HO2J
`
`
`7/00
`
`
`
`(2006.01)
`
`
`
`
`
`
`
`
`
`
`There is disclosed a system and method for transferring
`
`
`
`
`
`
`
`power without requiring direct electrical conductive con-
`
`
`
`
`
`
`
`tacts. There is provided a primary unit having a power
`
`
`
`
`
`
`
`supply and a substantially laminar charging surface having
`
`
`
`
`
`
`
`
`at least one conductorthat generates an electromagnetic field
`
`
`
`
`
`
`
`when a current flows therethrough and having an charging
`
`
`
`
`
`
`
`
`area defined within a perimeter of the surface, the at least
`
`
`
`
`
`
`
`one conductor being arranged such that electromagnetic
`
`
`
`
`
`
`
`
`
`
`field lines generated by the at
`least one conductor are
`
`
`
`
`
`
`
`
`substantially parallel to the plane of the surface or at least
`
`
`
`
`
`
`
`
`
`
`subtend an angle of 45° or less to the surface within the
`
`
`
`
`
`
`
`
`charging area; and at least one secondary device including at
`
`
`
`
`
`
`
`
`least one conductor that may be wound about a core.
`
`
`
`
`
`
`
`
`Because the electromagnetic field is spread over the charg-
`
`
`
`
`
`
`
`
`ing area and is generally parallel or near-parallel thereto,
`
`
`
`
`
`
`
`
`coupling with flat secondary devices such as mobile tele-
`
`
`
`
`
`
`
`
`phones and the like is significantly improved in various
`orientations thereof.
`
`
`
`
`
`Capacitor 2
` Circuit 2
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`Magnetic Unit
`
`
`
`
`Magnetic
`
`material .
`
`
`Conversion: Unit
`
`860 -
`
`
`
`
`Capacitor 1
`
`
`
`
`
`
`
`Page 1 of 41
`
`Volkswagen Exhibit 1030
`
`Page 1 of 41
`
`Volkswagen Exhibit 1030
`
`

`

`
`
`
`
`
`
`
`Patent Application Publication Mar. 23, 2006 Sheet 1 of 24
`
`
`
`US 2006/0061323 Al
`
`qpeunbi-4
`
`
`(uy40d)
`
`eyainbi{
`
`(UYJOU)
`
`
`
`Page 2 of 41
`
`Page 2 of 41
`
`
`
`

`

`
`
`
`
`
`
`Patent Application Publication Mar. 23, 2006 Sheet 2 of 24
`
`
`
`US 2006/0061323 Al
`
`(UY40ld)
`
`
`ezainbi-
`
`
`
`qzaunbi4
`
`Wwuc¢=x
`
`
`
`os(@GH|Me y
`
`
`
`1
`
`
`
`
`lal
`
`
`
`
`Page 3 of 41
`
`Page 3 of 41
`
`

`

`
`
`
`
`
`
`Patent Application Publication Mar. 23,2006 Sheet 3 of 24
`
`
`
`US 2006/0061323 Al
`
`im
`
`C4.
`co
`~
`‘©
`
`~)
`iS
`—)
`i=)
`
`=
`
`
`
`Page 4 of 41
`
`Page 4 of 41
`
`

`

`=22<
`
`bors
`
`
`
`
`xYLLLLLLLLLLLL
`SyZZLZLLLLLLOgLfffLLLf/ff/fSTS
`°[LLLLLLOLLO3ZL££f/fffff/fl/lilil/l)TY
`:OeZ
`
`
`
`
`epainbie
`
`
`
`
`
`Page 5 of 41
`
`
`
`

`

`TIESAi
`
`JFUSESLilia7,
`
`Oronbil-j
`
`Page 6 of 41
`
`
`
`

`

`
`
`US 2006/0061323 Al
`
`
`
`RRO
`
`
`
`
`
`
`
`Patent Application Publication Mar. 23, 2006 Sheet 6 of 24
`
`SOLS
`
`Opoinbi{
`
`
`
`Nee
`
`Page 7 of 41
`
`Page 7 of 41
`
`
`

`

`
`
`
`Sheet 7 of 24
`
`
`
`US 2006/0061323 Al
`
`O€Z
`
`ppaunbiy
`
`
`
`
`
`Patent Application Publication Mar. 23, 2006
`
`LEAL 028
`
`Page 8 of 41
`
`
`
`Page 8 of 41
`
`

`

`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`700
`
`800
`
`£/|O;,0O2Lha
`aE]
`
`cC)}2)|)2Di3/53
`
`2NwloiinN
`
`Magnetic Unit
`
`Magnetic
`material
`
`
`
`
`Magnetic
`material
`
`Control Unit
`
`7
`
`Capacitors
`
`Sensing Unit
`780
`
`PatentApplicationPublicationMar.23,2006Sheet8of24
`
`
`
`
`
`
`
`Capacitor 2
`
`
`
`US2006/0061323Al
`
`Figure 5
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`Page 9 of 41
`
`
`
`
`
`
`
`
`

`

`
`
`US 2006/0061323 Al
`
`q9aunbly
`
`ee ee a ae en we oe we me oe ne ee oe ae oy
`
`
`
`
`
`1tE at'
`
`1J
`
`uw)
`wz
`ew
`
`|
`
`
`
`
`
`SplObd|OnOld
`
`
`
`
`
`
`
`Patent Application Publication Mar. 23, 2006 Sheet 9 of 24
`
`7
`
`
`
`egainbly
`
`r
`
`t
`
`Spl
`
`t'
`!
`
`Page 10 of 41
`
`Page 10 of 41
`
`
`
`

`

`
`
`
`
`
`
`Patent Application Publication Mar. 23, 2006 Sheet 10 of 24
`
`
`
`US 2006/0061323 Al
`
`
`
`
`
`a-
`
`oe,
`
`~
`
`~-~oeee---"
`
`
`
`99aunbi-{
`
`Page 11 of 41
`
`
`
`pgainbl4
`
`Page 11 of 41
`
`
`

`

`
`
`
`
`
`
`Patent Application Publication Mar. 23, 2006 Sheet 11 of 24
`
`
`
`US 2006/0061323 Al
`
`
`
`“4
`
`'t}1'i'4V’''a‘''I!J‘t41tai'v‘t115ti'1'tt'1'y'11t51tii4
`
`
`
`7OSZ
`
`O12
`
`
`
`''t
`1a
`'a
`it
`'4
`
`t'''114;1ttI1\t'!''t!1i
`
`)i5
`‘t
`J1i
`3i1
`
`ai'1a'1''u
`
`
`
`
`
`99aINbBIY
`
`
`
`#9ainbly
`
`Page 12 of 41
`
`Page 12 of 41
`
`
`
`
`

`

`
`
`
`
`
`
`
`
`US 2006/0061323 Al
`
`
`
`Patent Application Publication Mar. 23, 2006 Sheet 12 of 24
`
`
`
`
`
`
`
`Page 13 of 41
`
`Page 13 of 41
`
`

`

`
`
`
`
`Patent Application Publication Mar. 23, 2006
`
`
`
`
`
`
`
`
`
`
`
`ObZ
`
`
`Sheet 13 of 24
`
`
`
`US 2006/0061323 Al
`
`
`
`I9einbly
`
`
`
`
`
`YF||LOAAASAADA’fpflfoffofiotptpppottotphplLal
`
`
`
`
`
`
`
`Page 14 of 41
`
`Page 14 of 41
`
`
`

`

`
`
`
`
`
`
`Patent Application Publication Mar. 23, 2006 Sheet 14 of 24
`
`
`
`US 2006/0061323 Al
`
`009
`
`
`
`072
`
`88ZOL.
`
`OLZ
`
`
`
`Page 15 of 41
`
`Page 15 of 41
`
`
`

`

`
`
`Page 16 of 41
`
`

`

`
`
`
`
`
`
`Patent Application Publication Mar. 23, 2006 Sheet 16 of 24
`
`
`
`US 2006/0061323 Al
`
`
`
`Figure7b
`
`810
`
`820
`
`
`
`820
`
`
`
`Figure7a
`
`
`
`
`
`
`
`
`
`810
`
`Page 17 of 41
`
`
`
`Page 17 of 41
`
`

`

`
`Patent Application
`
`
`Publication
`
`
`
`
`Mar.23, 2006
`
`
`
`
`Sheet 17 of 24
`
`
`
`~—US 2006/0061323 Al
`
`pgainbig
`
`
`
`
`
`
`
`
`
`
`Page 18 of 41
`
`Page 18 of 41
`
`

`

`
`
`
`
`
`
`Patent Application Publication Mar. 23,2006 Sheet 18 of 24
`
`
`
`US 2006/0061323 A1
`
`
`
`Figure8e
`
`
`
`
`
`
`
`
`
`Page 19 of 41
`
`

`

`
`
`
`
`
`
`Patent Application Publication Mar. 23,2006 Sheet 19 of 24
`
`
`
`US 2006/0061323 Al
`
`
`
`720
`
`740
`
`Figure9b
`
`
`Figure9a
`
`SEE
`
`“COPS 3
`eli
`PCCee
`COCCCMLETCe
`CEPCeeECCeere
`
`
`
`740
`
`
`
`Page 20 of 41
`
`Page 20 of 41
`
`

`

`
`
`
`
`
`
`Patent Application Publication Mar. 23, 2006 Sheet 20 of 24
`
`
`
`US 2006/0061323 Al
`
`
`
`OLainbl4
`
`Page 21 of 41
`
`Page 21 of 41
`
`

`

`US 2006/0061323 Al Q
`
`
`
`
`
`N3
`
`8
`
`930
`
`Page 22 of 41
`
`
`
`
`
`
`
`Patent Application Publication Mar. 23, 2006 Sheet 21 of 24
`
`
`
`
`
`©
`re
`re
`
`©—
`
`S
`
`
`
`
`8
`re
`
`re
`
`™ ©SS
`
`)
`LL
`
`o
`_—
`™
`
`©>
`
`it
`
`Page 22 of 41
`
`

`

`
`
`Page 23 of 41
`
`

`

`
`
`Page 24 of 41
`
`

`

`
`
`
`
`
`
`Patent Application Publication Mar. 23, 2006 Sheet 24 of 24
`
`
`
`US 2006/0061323 Al
`
`
`
`
`
`Lor
`
`SnOLES
`
`
`Hnos}00@ch
`quoez40ZZ
`suoorkgh—|78891
`
`296GON9}C=1¢
`Epandy
`
`NAACL
`vraisF=
`Old=
`
`ZHAB'ES
`
`096
`
`
`
`Page 25 of 41
`
`Page 25 of 41
`
`
`

`

`
`
`US 2006/0061323 Al
`
`
`
`Mar.23, 2006
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`the devices still need to be placed
`above. For example,
`
`
`
`
`
`
`
`
`
`accurately into a charger such that the device and the charger
`
`
`
`
`
`
`
`
`are in a predefined relative position (See FIGS. 1a and 1b).
`
`
`
`
`
`
`
`
`
`The adaptorsare still only designed specifically for a certain
`
`
`
`
`
`
`
`
`
`
`make and model of device and are still only capable of
`
`
`
`
`
`
`
`
`charging one device at a time. As a result, users still need to
`
`
`
`
`
`
`possess and manage a collection of different adaptors.
`
`
`
`
`
`
`
`[0010] Universal chargers (such as the Maha MH-C777
`
`
`
`
`
`
`
`
`
`Plus Universal charger) also exist such that battery packs of
`
`
`
`
`
`
`
`
`different shapes and characteristics can be removed from the
`
`
`
`
`
`
`
`
`device and charged using a single device. Whilst
`these
`
`
`
`
`
`
`
`
`universal chargers eliminate the need for having different
`
`
`
`
`
`
`
`
`
`chargers for different devices, they create even more incon-
`
`
`
`
`
`
`
`
`
`
`
`venience for the user in the sense that the battery packsfirst
`
`
`
`
`
`
`
`need to be removed, then the charger needs to be adjusted
`
`
`
`
`
`
`
`and the battery pack needs to be accurately positioned in or
`
`
`
`
`
`
`
`
`
`relative to the charger. In addition, time must be spent to
`
`
`
`
`
`
`
`
`
`determine the correct pair of battery pack metal contacts
`
`
`
`
`
`which the charger must use.
`
`
`
`
`
`
`
`
`
`[0011]
`It is known from USS. Pat. No. 3,938,018 “induc-
`
`
`
`
`
`
`tion charging system” to provide a means for non-contact
`
`
`
`
`
`battery charging whereby an inductive coil on the primary
`
`
`
`
`
`
`side aligns with a horizontal inductive coil on a secondary
`
`
`
`
`
`
`device whenthe device is placed into a cavity on the primary
`
`
`
`
`
`
`
`side. The cavity ensures the relatively precise alignment
`
`
`
`
`
`
`
`which is necessary with this design to ensure that good
`
`
`
`
`
`
`coupling is achieved between the primary and secondary
`coils.
`
`
`
`
`
`
`
`
`
`
`
`It is also known from U.S. Pat. No. 5,959,433
`[0012]
`
`
`
`
`
`
`“Universal Inductive Battery Charger System” to provide a
`
`
`
`
`
`
`
`non-contact battery charging system. The battery charger
`
`
`
`
`
`
`
`described includes a single charging coil which creates
`
`
`
`
`
`
`
`
`magnetic flux lines which will induce an electrical current in
`
`
`
`
`
`
`
`
`
`a battery pack which maybelongto cellular phonesor laptop
`
`computers.
`
`
`
`
`
`
`
`
`
`
`[0013]
`It is also known from U.S. Pat. No. 4,873,677
`
`
`
`
`
`
`“Charging Apparatus for an Electronic Device” to provide
`
`
`
`
`
`
`
`
`an apparatus for charging an electronic device which
`
`
`
`
`
`
`
`
`
`includes a pair of coils. This pair of coils is designed to
`
`
`
`
`
`
`
`
`
`operate in anti-phase such that magnetic flux lines are
`
`
`
`
`
`
`
`
`
`coupled from onecoil to the other. An electronic device such
`
`
`
`
`
`
`
`
`
`as a watch can be placed on these two coils to receive power.
`
`
`
`
`
`
`
`
`
`
`[0014]
`It is also known from U.S. Pat. No. 5,952,814
`
`
`
`
`
`
`
`“Induction charging apparatus and an electronic device” to
`
`
`
`
`
`
`
`provide an induction charger for charging a rechargeable
`
`
`
`
`
`
`
`
`
`battery. The shape of the external casing of the electronic
`
`
`
`
`
`
`
`
`device matches the internal shape of the charger thus allow-
`
`
`
`
`
`
`
`
`ing for accurate alignment of the primary and secondary
`coils.
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`[0015]
`It is also known from U.S. Pat. No. 6,208,115
`
`
`
`
`
`
`“battery substitute pack” to provide a substitute battery pack
`
`
`
`
`which maybe inductively recharged.
`
`
`
`
`
`
`
`
`[0016]
`It is known from WO 00/61400 “Device for Induc-
`
`
`
`
`
`
`tively Transmitting Electrical Power” to provide a means of
`
`
`
`
`transferring power inductively to conveyors.
`
`
`
`
`
`
`
`
`[0017]
`It is known from WO 95/11545 “Inductive power
`
`
`
`
`
`
`
`pick-up coils” to provide a system for inductive powering of
`
`
`
`
`
`
`
`electric vehicles from a series of in-road flat primaries.
`
`
`
`
`
`
`
`
`To overcome the limitations of inductive power
`[0018]
`
`
`
`
`
`
`
`transfer systems which require that secondary devices be
`
`
`
`CONTACT-LESS POWER TRANSFER
`
`
`
`
`
`
`
`[0001] The present application claims priority from UK
`
`
`
`
`
`
`
`
`patent applications nos 0210886.8 of 13 May 2002,
`
`
`
`
`
`
`
`0213024.3 of 7 Jun. 2002, 0225006.6 of 28 Oct. 2002 and
`
`
`
`
`
`
`
`
`
`0228425.5 of 6 Dec. 2002, as well as from U.S. patent
`
`
`
`
`
`
`
`
`application Ser. No. 10/326,571 of 20 Dec. 2002. The full
`
`
`
`
`
`
`
`
`contents of all of these prior patent applications is hereby
`
`
`
`
`
`
`incorporated into the present application by reference.
`
`
`
`
`
`
`
`[0002] This invention relates to a new apparatus and
`
`
`
`
`
`
`method for transferring power in a contact-less fashion.
`
`
`
`
`
`
`
`[0003] Manyof today’s portable devices incorporate “sec-
`
`
`
`
`
`
`
`
`
`ondary” powercells which can be recharged, saving the user
`
`
`
`
`
`
`
`the cost and inconvenience of regularly having to purchase
`
`
`
`
`
`
`
`new cells. Example devices include cellular telephones,
`
`
`
`
`
`
`
`
`laptop computers, the Palm 500 series of Personal Digital
`
`
`
`
`
`
`
`Assistants, electric shavers and electric toothbrushes. In
`
`
`
`
`
`
`
`
`
`someof these devices, the cells are recharged via inductive
`
`
`
`
`
`
`
`coupling rather than direct electrical connection. Examples
`
`
`
`
`
`
`
`
`
`include the Braun Oral B Plak Control power toothbrush,the
`
`
`
`
`
`
`Panasonic Digital Cordless Phone Solution KX-PH15AL
`
`
`
`
`
`
`
`and the Panasonic multi-head men’s shavers ES70/40 series.
`
`
`
`
`
`
`
`[0004] Each of these devices typically has an adaptor or
`
`
`
`
`
`
`
`
`charger which takes power from mains electricity, a car
`
`
`
`
`
`
`
`cigarette lighter or other sources of power and converts it
`
`
`
`
`
`
`
`
`
`into a form suitable for charging the secondary cells. There
`
`
`
`
`
`
`are a number of problems associated with conventional
`
`
`
`
`
`means of powering or charging these devices:
`
`
`
`
`
`
`
`[0005] Both the characteristics of the cells within each
`
`
`
`
`
`
`device and the means of connecting to them vary
`
`
`
`
`considerably from manufacturer to manufacturer, and
`from device to device. Therefore users who own sev-
`
`
`
`
`
`
`
`eral such devices must also own several different
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`adaptors. If users are going away ontravel, they will
`
`
`
`
`
`
`have to bring their collection of chargers if they expect
`
`
`
`
`
`
`
`to use their devices during this time.
`
`
`
`
`
`
`
`
`[0006] These adaptors and chargers often require users
`
`
`
`
`
`
`
`
`
`to plug a small connectorinto the device or to place the
`
`
`
`
`
`
`
`device with accurate alignment into a stand causing
`
`
`
`
`
`
`
`inconvenience. If users fail to plug or place their device
`
`
`
`
`
`
`
`
`
`into a charger and it runs out of power, the device
`
`
`
`
`
`
`
`
`becomesuseless and important data stored. locally in
`
`
`
`
`
`the device might even belost.
`
`
`
`
`
`
`
`
`[0007]
`In addition, most adaptors and chargers have to
`
`
`
`
`
`
`
`
`
`be plugged into mains sockets and henceif several are
`
`
`
`
`
`
`
`
`
`used together, they take up space in plug strips and
`
`
`
`
`
`
`
`create a messy and confusing tangle of wires.
`
`
`
`
`
`
`
`[0008] Besides the above problems with conventional
`
`
`
`
`
`
`
`methods of recharging devices, there are also practical
`
`
`
`
`
`
`
`problemsassociated with devices having an open elec-
`
`
`
`
`
`
`
`trical contact. For example, devices cannot be used in
`
`
`
`
`
`
`wet environments dueto the possibility of corroding or
`
`
`
`
`
`
`
`
`
`shorting out the contacts and also they cannot be used
`
`
`
`
`
`
`
`in flammable gaseous environments due to the possi-
`
`
`
`
`
`bility of creating electrical sparks.
`
`
`
`
`
`
`
`[0009] Chargers which use inductive charging remove the
`
`
`
`
`
`
`
`need to have open electrical contacts hence allowing the
`
`
`
`
`
`
`
`adaptor and device to be sealed and used in wet environ-
`
`
`
`
`
`
`
`ments (for example the electric toothbrush as mentioned
`
`
`
`
`
`above is designed to be used in a bathroom). However such
`
`
`
`
`
`
`
`chargers still suffer from all other problems as described
`Page 26 of 41
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`Page 26 of 41
`
`

`

`
`
`US 2006/0061323 Al
`
`
`
`Mar.23, 2006
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`transferring power to portable devices with all of the fol-
`
`
`
`
`
`
`lowing features andis cost effective to implement:
`
`
`
`
`
`
`[0022] Universality: a single primary unit which can
`
`
`
`
`
`
`supply power to different secondary devices with dif-
`
`
`
`
`
`
`ferent power requirements thereby eliminating the need
`
`
`
`
`
`
`for a collection of different adaptors and chargers;
`
`
`
`
`
`
`[0023] Convenience: a single primary unit which allows
`
`
`
`
`
`
`secondary devices to be placed anywhere within an
`
`
`
`
`
`
`
`active vicinity thereby eliminating the need for plug-
`
`
`
`
`
`
`ging-in or placing secondary devices accurately rela-
`
`
`
`
`
`tive to an adaptor or charger;
`
`
`
`
`
`
`that can
`[0024] Multiple-load: a single primary unit
`
`
`
`
`
`supply power to a number of secondary different
`
`
`
`
`
`
`devices with different power requirements at the same
`
`time;
`
`
`
`
`
`
`[0025] Flexibility for use in different environments: a
`
`
`
`
`
`
`
`
`single primary unit that can supply power to secondary
`
`
`
`
`
`
`
`devices such that no direct electrical contact is required
`
`
`
`
`
`
`
`thereby allowing for secondary devices and the primary
`
`
`
`
`
`
`
`
`unit itself to be used in wet, gaseous, clean and other
`
`
`atypical environments;
`
`
`
`
`
`
`[0026] Low electromagnetic emissions: a primary unit
`
`
`
`
`
`
`
`
`that can deliver power in a manner that will minimize
`
`
`
`
`
`
`
`
`the intensity and size of the magnetic field generated.
`
`
`
`
`
`
`
`
`
`It is further to be appreciated that portable appli-
`[0027]
`
`
`
`
`
`
`
`
`
`ances are proliferating and they all need batteries to power
`
`
`
`
`
`
`
`them. Primary cells, or batteries of them, must be disposed
`
`
`
`
`
`
`
`of once used, which is expensive and environmentally
`
`
`
`
`
`
`
`unfriendly. Secondarycells or batteries can be recharged and
`
`
`
`
`used again and again.
`
`
`
`
`
`
`
`
`[0028] Manyportable devices have receptacles for cells of
`
`
`
`
`
`
`
`
`an industry-standard size and voltage, such as AA, AAA, C,
`D and PP3. This leaves the user free to choose whether to
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`use primary or secondary cells, and of various types. Once
`
`
`
`
`
`
`
`
`depleted, secondary cells must typically be removed from
`
`
`
`
`
`
`
`
`the device and placed into a separate recharging unit.
`
`
`
`
`
`
`
`Alternatively, some portable devices do have recharging
`
`
`
`
`
`
`
`circuitry built-in, allowing cells to be recharged in-situ once
`
`
`
`
`
`
`
`the device is plugged-in to an external source of power.
`
`
`
`
`
`
`
`
`
`[0029]
`It is inconvenient for the user to have to either
`
`
`
`
`
`
`
`
`remove cells from the device for recharging, or to have to
`
`
`
`
`
`
`
`
`plug the device into an external power source for recharging
`
`
`
`
`
`
`
`in-situ. It would be far preferable to be able to recharge the
`
`
`
`
`
`
`
`cells without doing either, by some non-contact means.
`
`
`
`
`
`
`
`
`[0030] Some portable devices are capable of receiving
`
`
`
`
`
`
`
`
`powercoupled inductively from a recharger, for example the
`
`
`
`
`
`
`
`Braun Oral B Plak Control
`toothbrush. Such portable
`
`
`
`
`
`
`devices typically have a custom, dedicated power-receiving
`
`
`
`
`
`
`
`
`module built-in to the device, which then interfaces with an
`
`
`
`
`
`
`
`internal standard cell or battery (which may or may not be
`
`removable).
`
`
`
`
`
`
`[0031] However it would be convenientif the user could
`
`
`
`
`
`
`transform any portable device which accepts industry-stan-
`
`
`
`
`
`
`dard cell sizes into an inductively-rechargeable device,
`
`
`
`
`simply byfitting inductively-rechargeable cells or batteries,
`
`
`
`
`
`
`
`which could then be recharged in-situ by placing the device
`
`
`
`onto an inductive recharger.
`
`
`
`
`
`
`
`
`
`[0032] Examples of prior art include U.S. Pat. No. 6,208,
`
`
`
`
`
`
`
`
`115, which discloses a substitute battery pack which may be
`
`
`inductively recharged.
`
`
`
`
`
`
`
`
`
`
`
`axially aligned with the primary unit, one might proposethat
`
`
`
`
`
`
`
`
`
`an obvious solution is to use a simple inductive power
`
`
`
`
`
`
`
`
`
`transfer system whereby the primary unit
`is capable of
`
`
`
`
`
`
`
`
`emitting an electromagneticfield over a large area (See FIG.
`
`
`
`
`
`
`
`
`
`2a). Users can simply place one or more devices to be
`
`
`
`
`
`
`
`
`recharged within range of the primary unit, with no require-
`
`
`
`
`
`
`
`
`
`mentto place them accurately. For example this primary unit
`
`
`
`
`
`
`
`
`may consist of a coil encircling a large area. When a current
`
`
`
`
`
`
`
`
`flows through the coil, an electromagnetic field extending
`
`
`
`
`
`
`
`
`
`over a large area is created and devices can be placed
`
`
`
`
`
`
`
`anywhere within this area. Although theoretically feasible,
`
`
`
`
`
`
`
`
`this method suffers from a numberof drawbacks.Firstly, the
`
`
`
`
`
`intensity of electromagnetic emissions is governed by regu-
`
`
`
`
`
`
`
`
`
`
`latory limits. This means that this method can only support
`
`
`
`
`
`
`
`
`
`powertransfer at a limited rate. In addition, there are many
`
`
`
`
`
`
`
`objects that can be affected by the presence of an intense
`
`
`
`
`
`
`
`
`
`magnetic field. For example, data stored on credit cards
`
`
`
`
`
`
`
`
`maybe destroyed and objects made of metal will have
`
`
`
`
`
`
`
`induced therein eddy currents generating undesired heating
`
`
`
`
`
`
`
`effects. In addition,
`if a secondary device comprising a
`
`
`
`
`
`
`
`
`conventional coil (see FIG. 2a) is placed against a metallic
`
`
`
`
`
`
`
`plate such as a copper plane in a printed circuit board or
`
`
`
`
`
`
`
`metallic can of a cell, coupling is likely to be significantly
`reduced.
`
`
`
`
`
`
`
`
`
`
`[0019] To avoid the generation of large magnetic fields,
`
`
`
`
`
`
`
`
`
`one might suggest using an array of coils (See FIG. 3)
`
`
`
`
`
`
`
`
`
`whereby only the coils needed are activated. This method is
`
`
`
`
`
`
`
`described in a paper published in the Journal of the Mag-
`
`
`
`
`
`
`
`
`netics Society of Japan titled “Coil Shape in a Desk-type
`
`
`
`
`
`
`
`
`Contactless Power Station System” (29 Nov. 2001). In an
`
`
`
`
`
`
`embodiment of the multiple-coil concept, a sensing mecha-
`
`
`
`
`
`
`
`
`
`nism senses the relative location of the secondary device
`
`
`
`
`
`
`
`
`relative to the primary unit. A control system then activates
`
`
`
`
`
`
`
`
`the appropriate coils to deliver power to the secondary
`
`
`
`
`
`
`
`device in a localised fashion. Although this method provides
`
`
`
`
`
`
`
`a solution to the problemspreviously listed, it does so in a
`
`
`
`
`
`
`
`
`
`complicated and costly way. The degree to which the
`
`
`
`
`
`
`
`primary field can be localised is limited by the number of
`
`
`
`
`
`
`
`
`
`
`coils and hence the numberof driving circuits used (i.e. the
`
`
`
`
`
`
`
`
`“resolution” of the primary unit). The cost associated with a
`
`
`
`
`
`
`
`multiple-coil system would severely limit the commercial
`
`
`
`
`
`
`applications of this concept. Non-uniform field distribution
`is also a drawback. When all the coils are activated in the
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`primary unit, they sum to an equivalent of a large coil, the
`
`
`
`
`
`
`
`magnetic field distribution of which is seen to exhibit a
`minimum at the centre of the coil.
`
`
`
`
`
`
`
`
`
`
`
`
`
`[0020] Another schemeis outlined in U.S. Pat. No. 5,519,
`
`
`
`
`
`
`
`
`262 “Sear Field Power Coupling System”, whereby a pri-
`
`
`
`
`
`
`
`
`mary unit has a number of narrow inductive coils (or
`
`
`
`
`
`
`
`
`alternatively capacitive plates) arranged from one end to the
`
`
`
`
`
`
`
`
`other of a flat plate, creating a number of vertical fields
`
`
`
`
`
`
`
`which are driven in a phase-shifted manner so that a sinu-
`
`
`
`
`
`
`
`
`soidal wave of activity moves across the plate. A receiving
`
`
`
`
`
`
`
`
`
`device has two vertical
`field pickups arranged so that
`
`
`
`
`
`
`
`regardless of its position on the plate it can always collect
`
`
`
`
`
`
`
`
`
`power from at least one pickup. While this scheme also
`
`
`
`
`
`
`
`
`offers freedom of movement of the device,
`it has the
`
`
`
`
`
`
`disadvantages of needing a complex secondary device, hav-
`
`
`
`
`
`
`
`
`
`ing a fixed resolution, and having poor coupling because the
`
`
`
`
`
`return flux path is through air.
`
`
`
`
`
`
`
`
`[0021] None of the prior art solutions can satisfactorily
`
`
`
`
`
`
`
`
`
`address all of the problems that have been described. It
`
`
`
`
`
`
`would be convenient to have a solution which is capable of
`Page 27 of 41
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`Page 27 of 41
`
`

`

`
`
`US 2006/0061323 Al
`
`
`
`Mar.23, 2006
`
`
`
`
`
`
`
`
`
`
`
`[0033] According to a first aspect of the present invention,
`
`
`
`
`
`
`
`there is provided a system for transferring power without
`
`
`
`
`
`
`
`requiring direct electrical conductive contacts, the system
`
`comprising:
`
`
`
`
`
`
`
`[0034]
`i) a primary unit including a substantially laminar
`
`
`
`
`
`
`
`charging surface and at least one means for generating an
`
`
`
`
`
`
`
`
`electromagnetic field, the means being distributed in two
`
`
`
`
`
`
`dimensionsacross a predeterminedareain or parallel to the
`
`
`
`
`
`
`
`charging surface so as to define at least one charging area of
`
`
`
`
`
`
`
`the charging surface that is substantially coextensive with
`
`
`
`
`
`
`
`
`
`the predeterminedarea, the charging area having a width and
`
`
`
`
`
`
`
`
`
`a length on the charging surface, wherein the means is
`
`
`
`
`
`
`
`configured such that, when a predetermined current is sup-
`
`
`
`
`
`
`
`
`
`plied thereto and the primary unit is effectively in electro-
`
`
`
`
`
`magnetic isolation, an electromagnetic field generated by the
`
`
`
`
`
`
`
`
`means has electromagnetic field lines that, when averaged
`
`
`
`
`
`
`
`
`
`over any quarter length part of the charging area measured
`
`
`
`
`
`
`
`parallel to a direction of the field lines, subtend an angle of
`
`
`
`
`
`
`
`
`
`45° or less to the charging surface in proximity thereto and
`
`
`
`
`
`
`
`
`are distributed in two dimensions thereover, and wherein the
`
`
`
`
`
`
`means has a height measured substantially perpendicular to
`
`
`
`
`
`
`
`
`
`
`the charging area that is less than either of the width or the
`
`
`
`
`
`length of the charging area; and
`
`
`
`
`
`
`
`
`[0035]
`ii) at least one secondary device includingat least
`
`
`
`one electrical conductor;
`
`
`
`
`
`
`
`[0036] wherein, when the at least one secondary device is
`
`
`
`
`
`
`placed on or in proximity to a charging area of the primary
`
`
`
`
`
`
`
`
`
`unit, the electromagnetic field lines couple with the at least
`
`
`
`
`
`
`
`
`
`one conductor of the at least one secondary device and
`induce a current to flow therein.
`
`
`
`
`
`
`
`
`
`
`
`[0037] According to a second aspectof the present inven-
`
`
`
`
`
`
`
`
`tion, there is provided a primary unit for transferring power
`
`
`
`
`
`
`
`without requiring direct electrical conductive contacts, the
`
`
`
`
`
`
`primary unit
`including a substantially laminar charging
`
`
`
`
`
`
`
`
`surface and at least one means for generating an electro-
`
`
`
`
`
`
`
`
`magnetic field, the means being distributed in two dimen-
`
`
`
`
`
`
`
`
`
`sions across a predetermined area in or parallel
`to the
`
`
`
`
`
`
`
`charging surface so as to define at least one charging area of
`
`
`
`
`
`
`
`the charging surface that is substantially coextensive with
`
`
`
`
`
`
`
`
`
`the predeterminedarea, the charging area having a width and
`
`
`
`
`
`
`
`
`
`a length on the charging surface, wherein the means is
`
`
`
`
`
`
`
`configured such that, when a predetermined current is sup-
`
`
`
`
`
`
`
`
`
`plied thereto and the primary unit is effectively in electro-
`
`
`
`
`
`magnetic isolation, an electromagnetic field generated by the
`
`
`
`
`
`
`
`
`means has electromagnetic field lines that, when averaged
`
`
`
`
`
`
`
`
`
`over any quarter length part of the charging area measured
`
`
`
`
`
`
`
`parallel to a direction of the field lines, subtend an angle of
`
`
`
`
`
`
`
`
`
`45° or less to the charging surface in proximity thereto and
`
`
`
`
`
`
`
`
`are distributed in two dimensions thereover, and wherein the
`
`
`
`
`
`
`means has a height measured substantially perpendicular to
`
`
`
`
`
`
`
`
`
`
`the charging area that is less than either of the width or the
`
`
`
`
`length of the charging area.
`
`
`
`
`
`
`
`[0038] According to a third aspect of the present inven-
`
`
`
`
`
`
`tion, there is provided a method of transferring powerin a
`
`
`
`
`
`
`non-conductive manner from a primary unit to a secondary
`
`
`
`
`
`
`
`device, the primary unit including a substantially laminar
`
`
`
`
`
`
`
`charging surface and at least one means for generating an
`
`
`
`
`
`
`
`
`electromagnetic field, the means being distributed in two
`
`
`
`
`
`
`dimensionsacross a predeterminedareain or parallel to the
`
`
`
`
`
`
`
`charging surface so as to define at least one charging area of
`
`
`
`
`
`
`
`the charging surface that is substantially coextensive with
`
`
`
`
`
`
`
`
`
`the predeterminedarea, the charging area having a width and
`Page 28 of 41
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`a length on the charging surface, the means having a height
`
`
`
`
`
`
`measured substantially perpendicular to the charging area
`
`
`
`
`
`
`
`
`
`
`
`that is less than either of the width or the length of the
`
`
`
`
`
`
`
`
`
`charging area, and the secondary device havingat least one
`
`
`
`electrical conductor; wherein:
`
`
`
`
`
`
`i) an electromagnetic field, generated by the means
`[0039]
`
`
`
`
`
`
`
`when energised with a predetermined current and measured
`
`
`
`
`
`
`
`
`when the primary unit
`is effectively in electromagnetic
`
`
`
`
`
`
`
`
`isolation, has electromagnetic field lines that, when averaged
`
`
`
`
`
`
`
`
`
`over any quarter length part of the charging area measured
`
`
`
`
`
`
`
`parallel to a direction of the field lines, subtend an angle of
`
`
`
`
`
`
`
`
`45° or less to the charging surface in proximity thereto and
`are distributed in two dimensions over the at
`least one
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`
`charging area when averaged thereover; and
`
`
`
`
`
`
`
`
`
`[0040]
`ii) the electromagnetic field links with the conduc-
`
`
`
`
`
`
`
`
`
`tor of the secondary device when this is placed on or in
`
`
`
`
`proximity to the charging area.
`
`
`
`
`
`
`[0041] According to a fourth aspect of the present inven-
`
`
`
`
`
`
`
`
`tion, there is provided a secondary device for use with the
`
`
`
`
`
`
`
`system, unit or method ofthe first, second or third aspects,
`
`
`
`
`
`
`
`the secondary device including at least one electrical con-
`
`
`
`
`
`
`
`ductor and having a substantially laminar form factor.
`
`
`
`
`
`
`
`
`
`[0042]
`In the context of the present application, the word
`
`
`
`
`
`
`
`“laminar” defines a geometry in the form of a thin sheet or
`
`
`
`
`
`
`
`
`lamina. The thin sheet or lamina may be substantially flat, or
`
`
`may be curved.
`
`
`
`
`
`
`
`
`
`[0043] The primary unit may include an integral power
`
`
`
`
`
`
`
`
`
`supply for the at least one means for generating an electro-
`
`
`
`
`
`
`
`
`magnetic field, or may be provided with connectors or the
`
`
`
`
`
`
`
`like enabling the at least one means to be connected to an
`
`
`
`external power supply.
`
`
`
`
`
`
`
`[0044]
`In some embodiments, the means for generating
`
`
`
`
`
`
`
`the electromagnetic field have a height that is no more than
`
`
`
`
`
`
`
`
`
`half the width or half the length of the charging area; in some
`
`
`
`
`
`
`
`
`
`embodiments, the height may be no more than 1% of the
`
`
`
`
`
`
`
`width or Y of the length of the charging area
`
`
`
`
`
`
`
`
`[0045]
`Theat least one electrical conductor in the second-
`
`
`
`
`
`
`
`
`
`ary device may be wound about a core that serves to
`
`
`
`
`
`
`
`
`
`concentrate flux therein. In particular, the core (where pro-
`
`
`
`
`
`
`
`
`vided) mayoffer a path of least resistanceto flux lines of the
`
`
`
`
`
`
`
`electromagnetic field generated by the primary umit. The
`
`
`
`
`
`
`core may be amorphous magnetically permeable material. In
`
`
`
`
`
`
`
`some embodiments, there is no need for an amorphouscore.
`
`
`
`
`
`
`
`[0046] Where an amorphous core is provided, it is pre-
`
`
`
`
`
`
`
`ferred that
`the amorphous magnetic material
`is a non-
`
`
`
`
`
`
`
`annealed or substantially as-cast state. The material may be
`
`
`
`
`
`
`
`
`
`least 70% non-annealed, or preferably at
`least 90%
`at
`
`
`
`
`
`
`
`non-annealed. This is because annealing tends to make
`
`
`
`
`
`
`amorphous magnetic. materials brittle, which is disadvan-
`
`
`
`
`
`
`
`tageous when contained in a device, such as a mobile phone,
`
`
`
`
`
`
`
`which may be subjected to rough treatment, for example by
`
`
`
`
`
`
`being accidentally dropped.
`In a particularly preferred
`
`
`
`
`
`
`embodiment, the amorphous magnetic material is provided
`
`
`
`
`
`
`
`
`
`in the form of a fle