Heating appliance with uniform heating control

Claim 1

A heating appliance comprising: (a) heating means having at least a first, a second, a third and a fourth power level for heating an object, said heating means applying heat to the object during each power level, said third power level being greater than said second power level, said fourth power level being lower than said first power level; (b) sensor means for sensing the heating condition of said object and outputting a signal representative thereof; (c) detecting means, responsive to said output signal of said sensor means, for detecting whether said object has been heated to a predetermined heat completion condition; (d) switching means for switching from said first power level to said second power level to said third power level of said heating means prior to the detection of said predetermined heat completion condition of said object being heated; and controlling means for controlling said heating means to provide an additive heating period at the fourth power level for heating said object after said detecting means detects that said predetermined heat completion condition has been reached, said additive heating period being determined by the type of said object and the length of time from the start of said heating to the detection of said heating completion condition.