Patent ID: 8818223

Claim:
An image forming apparatus, comprising: an image forming section for forming a toner image on a medium; a heat source; a fixing rotating body receiving heat supplied from said heat source; a pressurizing rotating body adapted to form a nip portion with said fixing rotating body; a feeding section for feeding said medium at a speed synchronized with circumferential speed of said fixing rotating body and said pressurizing rotating body, so that said medium having said toner image formed thereon passes through said nip portion; a temperature adjusting section for controlling an amount of heat generated by said heat source so that temperature of said fixing rotating body attains to a prescribed value; and a control section for switching between a first mode in which said fixing rotating body and said pressurizing rotating body rotate at a first circumferential speed and said medium is fed to said image forming section at a first distance interval, and a second mode in which said fixing rotating body and said pressurizing rotating body rotate at a second circumferential speed higher than said first circumferential speed and said medium is fed to said image forming section at a second distance interval longer than said first distance interval, wherein a time cycle for feeding said medium in said first mode to said image forming section and a time cycle for feeding said medium in said second mode to said image forming section are the same so as to achieve a constant number of prints output per unit time.