An image forming apparatus has image forming means for forming an unfixed toner
image on a recording material, heating and fixing means for heating and fixing
the unfixed toner image on the recording material, temperature sensing means for
sensing the temperature of the heating and fixing means, and power controlling
means for controlling power supplied to the heating and fixing means so that the
heating and fixing means keeps a fixable temperature at least on fixing operation
based on an output from the temperature sensing means. The power controlling means
controls power supply to the heating and fixing means based on the output from
the temperature sensing element during the time from receipt of a print signal
by the image forming apparatus to performing a heating and fixing process on the
recording material so that, in the case where the temperature of the heating and
fixing means rises fast, a temperature control operation for keeping the fixable
temperature should not be protracted before heating and fixing so as to control
excessive rise in the temperature of the pressure member (pressure roller) and
prevent a media slip.
