Patent ID: 7109440

Claim:
A fusing system for use in an image forming apparatus, comprising: a fusing unit comprising: a fusing roller, and a heater, mounted inside the fusing roller, to heat the fusing roller; and a fusing temperature control unit comprising: a sensor unit to sense a surface temperature ‘T’ of the fusing roller, a power supply unit to supply power to the heater, and a controller comprising a timer to count time, and a memory to store therein a preset target temperature ‘Tt’ of a surface of the fusing roller, a preset temperature control period ‘t 0 ’ to determine a heater on and off time, a preset maximum power supply time ‘Max ON-time’ and a minimum power supply time ‘Min ON-time’ during which the power supply unit supplies power to the heater, and a minimum power cutoff time ‘Min OFF-time’ during which the power supply unit can cut off the power supply to the heater, the controller to control the surface temperature ‘T’ of the fusing roller by a control of the power supply to the heater in accordance with the target temperature ‘Tt’, the temperature control period ‘t 0 ’, the ‘Max ON-time’, the ‘Min ON-time’ or the ‘Min OFF-time’.