Patent ID: 7923971

Claim:
A non-contact electric power transmission apparatus having: a power supplying unit main body containing a power supplying coil for non-contact electric power transmission; a power receiving unit containing a power receiving coil for non-contact electric power transmission; and a supporting base for detachably mounting the power receiving unit, formed in a portion of the power supplying unit main body, the apparatus transmitting electric power from the power supplying coil to the power receiving coil in a non-contact manner using electromagnetic induction, wherein: the power receiving unit has a modulation circuit which outputs a recognition signal upon receiving electric power from the power supplying coil at the power receiving coil; the power supplying unit has detecting means, a demodulation circuit, a recognition circuit, and a timer circuit; the detecting means detects that the power receiving unit is placed on the supporting base of the power supplying unit to start electric power transmission from the power supplying coil, the recognition signal from the modulation circuit being detected as voltage change in the power supplying coil; the demodulation circuit demodulates the recognition signal to check whether or not it is a predetermined recognition signal, and if it is not the predetermined recognition signal, an output signal is applied to the timer circuit; and the timer circuit stops electric power transmission for a predetermined time period and thereafter restarts by checking again.