| 摘要 |
PURPOSE: To provide a safe cooking appliance whose element is hardly disrupted even when prescribed cooling cannot be obtained by using a power switching element whose total loss has a negative temperature characteristic in an inverter circuit. CONSTITUTION: A control circuit 6 controls a power switching element 4 in an ON and OFF system, and supplies a high frequency current to a heating coil 2. A material whose total loss being the sum of an electric continuity loss and a turnoff loss has a negative temperature characteristic to a case temperature is selectively used as this element 4. Therefore, a contact current Ic of the element 4 has a negative characteristic at high temperature time when normal temperature time is set as a reference, and even if the unexpected deterioration of cooling performance is caused, the element 4 is hardly disrupted. |
