US Patent 8210708 Induction rechargeable electronic candle system

A large plurality of artificial, battery-operated, electronic candles are arranged to be simultaneously recharged upon placement on a series of interconnected charging trays that include a transformer primary winding at defined locations thereon. The primary windings are driven by an AC signal whose duty cycle is controlled by a pulse width modulator IC to induce a voltage across secondary windings contained within the candle housing. This induced signal is rectified to produce the battery charging current and the delivery of the charging current to the rechargeable batteries is controlled by a microprocessor IC.