Patent ID: 7313339

Claim:
An image forming device comprising: a heater; a fixing film that conducts heat of said heater; and a pressure rotary body that presses on said fixing film; wherein said image forming device heats and presses a recording material for fixing an unfixed image thereon with the recording material nipped between said fixing film and said pressure rotary body, said unfixed image formed on the recording material, said image forming device further comprising: temperature adjusting means for maintaining said heater at a predetermined fixing temperature when the recording material is nipped for fixing; temperature sensing means for sensing a temperature of said heater; print speed control means for comparing the temperature sensed by said temperature sensing means with a predetermined threshold to control a print speed according to the comparison result; threshold switching means for switching the threshold according to a predetermined condition; and counting means for accumulating the number of executions of throughput reduction, said throughput reduction being executed for reducing the print speed by said print speed control means; wherein, as the predetermined condition, said threshold switching means uses a condition that the number of executions of throughput reduction, accumulated by said counting means, reaches a predetermined value.