Rechargeable battery powered portable electronic device
There is provided a planar inductive battery charging system designed to enable electronic devices to be recharged. The system includes a planar charging module having a charging surface on which a device to be recharged is placed. Within the charging module and parallel to the charging surface is at least one and preferably an array of primary windings that couple energy inductively to a secondary winding formed in the device to be recharged. The invention also provides secondary modules that allow the system to be used with conventional electronic devices not formed with secondary windings.
1. A battery powered portable electronic device comprising a rechargeable battery, and wherein said portable device includes a planar secondary winding for receiving electrical energy from a battery charger, and electromagnetic shielding between said winding and the major electronic components of said device, wherein said secondary winding lies in a plane parallel to a surface of said device adapted to be placed on a charging surface of a battery charging system, wherein said device is capable to being carried or moved by hand.
2. An electronic device as claimed in claim 1 wherein said shielding comprises a sheet of ferrite material and a sheet of conductive material.
3. An electronic device as claimed in claim 1 wherein said winding is formed integrally with a back cover of said device.
4. A secondary module for a battery charging system, comprising: a housing having at least one charging surface, a secondary winding provided in said housing parallel to said surface and adapted to receive magnetic flux when said surface is brought adjacent to a primary winding, circuit means for converting alternating current in said secondary winding to a regulated DC output, and a connector means for connecting said DC output to the charging socket of an electronic device.