Patent ID: 8032045

Claim:
A fusing device which fuses and fixes a toner onto a print paper, comprising: an AC current generating unit which generates an AC current having a frequency corresponding to a pulse width modulation signal; an insulation unit which receives the AC current and generates a magnetically induced current corresponding to the AC current; a fusing unit which is resistance heated or induction heated by the induced current, and fuses the toner onto the print paper using the generated heat; a sensing unit which senses the temperature of the fusing unit; a reference current generating unit which compares the temperature of the fusing unit sensed by the sensing unit with a predetermined reference temperature; and generates a predetermined reference current for controlling the temperature of the fusing unit based on the result of the comparison between the temperatures; and a pulse width modulation signal generating unit which compares the reference current with the induced current input to the fusing unit; generates the pulse width modulation signal for compensating for a difference between the induced current and the reference current based on the result of comparison of the currents; and outputs the pulse width modulation signal to the AC current generating unit.