Patent ID: 8658950

Claim:
A heating device for heating at least one foodstuff container, said heating device comprising: a first induction coil; a second induction coil; a control panel that issues an adjusting signal; a power supply unit connected with said first induction coil and said second induction coil for providing a first power and a second power to said first induction coil and said second induction coil, respectively; a controlling unit connected with said control panel and said power supply unit and generating a control signal to said power supply unit according to said adjusting signal, thereby controlling said first power and said second power of said power supply unit, wherein said controlling unit detects a plurality of heating parameters before a heating operation of said heating device is started, wherein said plurality of heating parameters include a first minimum frequency value, a second minimum frequency value, a first minimum power value and a second minimum power value; wherein electrical energy is transmitted to said first induction coil and said second induction coil and the frequency difference between said first power and said second power is greater than 15 kHz or smaller than 1 kHz during a first time interval after said heating operation of said heating device is started under control of said controlling unit, and no electrical energy is transmitted to one of said first induction coil and said second induction coil during a second time interval after said heating operation of said heating device is started under control of said controlling unit; wherein said controlling unit determines said first time interval, said second time interval and heat quantity of said at least one foodstuff container according to said first minimum frequency value, said second minimum frequency value, said first minimum power value and said second minimum power value.