An image fixing apparatus has a first rotatable member heated by a first heater
and a first temperature detecting element for detecting its temperature; a first
controller for controlling electric supply to the first heater to maintain a detected
temperature of the first temperature detecting element at a first target temperature;
a second rotatable member heated by a second heater and forming a fixing nip with
the first rotatable member; a second temperature detecting element for detecting
a temperature of the second rotatable member, a second controller for controlling
electric supply to the second heater to maintain the detected temperature of the
second temperature detecting element at a second target temperature; and a phase
controller for controlling electric energy supply phase so as to avoid overlapping
of a phase of an electric power supply to the first heater and a phase of an electric
power supply to the second heater.