Patent ID: 7633263

Claim:
A battery charger without electrical contacts comprising: a primary coil magnetically coupled to a secondary coil housed in portable electronic equipment; a high frequency power supply that supplies high frequency power to the primary coil; and an external case that holds the primary coil and the high frequency power supply, wherein the high frequency power supply converts input power to high frequency power and supplies it to the primary coil, primary coil high frequency power is conveyed to the secondary coil by magnetic induction, and secondary coil AC is rectified to charge the battery pack contained in the portable electronic equipment, the battery charger without electrical contacts is provided with internal batteries that are charged by input power and supply power to the high frequency power supply, and with a charging circuit that charges the internal batteries with input power, the external case is formed as a flat panel having a given thickness providing storage space for internal batteries between a top plate and a bottom plate, internal batteries housed in the external case storage space are rectangular batteries and these rectangular batteries are housed in the storage space with their two opposing flat surfaces oriented parallel to the top plate and bottom plate, and a planar primary coil wound in a spiral shape is disposed in the external case storage space or in the top plate, wherein the internal batteries are charged by input power; when no power is input, the high frequency power supply converts power supplied from the internal batteries to high frequency power and supplies it to the primary coil to charge the portable electronic equipment battery pack, and wherein the high frequency power supply contains a circuit to detect internal battery remaining capacity and supply DC power from the internal batteries to the high frequency power supply when remaining capacity is detected that is greater than a set capacity.