| 摘要 |
PURPOSE:To prevent the excessive rise of the temperature of a cooking utensil due to vacancy heating or the like by invariably monitoring the rising of the temperature of the cooking utensil and stopping the generation of the alternating magnetic field from a heating coil when the rising of the temperature of the cooking utensil is abrupt. CONSTITUTION:If an inverter is oscillated when nothing is left in a pot 6, the temperature rise of the pot 6 is quick, thus a temperature level signal VT rises quickly to reach a level higher than the holding voltage VTH updated in the 2T period, and the output of a comparator 27 is changed from the 'H' level to the 'L' level at this time. On receiving this 'L' level signal, a control circuit 8 stops the on/off drive of a switching transistor 4, and the heating action of the pot 6 is stopped. The quick vacancy heating protection can be thereby obtained. |
