Apple Inc.
INDUCTIVELY COUPLED POWER TRANSFER SYSTEMS

Abstract:

In an inductively coupled power transmitter a force detector that detects the presence of a potential device by monitoring forces applied to a surface of the power transmitter and activates the inductively coupled power transmitter upon detection of a potential device. An inductively coupled power transmitter having a proximity detector that detects the presence and location of a potential device by monitoring the proximity of devices to a surface of the power transmitter and activates the inductively coupled power transmitter upon detection of a potential device. The transmitter preferably has one or more detection coils each having an area much greater than that of the transmitter coils for detecting the presence of a potential device. An inductively coupled power transmitter including a plurality of transmitter coils proximate a charging surface and a controller selecting and driving a combination of transmitter coils providing the coupling between the power transmitter and a power receiver meeting a selection criteria.