| 摘要 |
PURPOSE:To reduce the heat radiation to the outside from a recording sheet discharge port at the time of waiting, utilize it for the heat insulation of a fixing roller, and prevent the infiltration of a foreign object by shielding the recording sheet discharge port with a shielding member when no recording sheet passes through it. CONSTITUTION:During the recording sheet fixing action, a recording sheet 7 enters a nip section of a fixing roller 1 and a pressing roller 3, it proceeds in the rotating direction of both rollers 1, 3, and the excitation quantity to a heater 2 is controlled by a temperature control circuit in response to the detection signal of a temperature detecting element 4. A toner image is fixed by heat on the recording sheet 7 in the passing process through the nip section, then the recording sheet 7 is separated from the surface of the fixing roller 1 by a separating claw 6, and it is discharged to the outside of a fixing device through a recording sheet discharge port 9 by a pair of discharge rollers 8. A shielding plate 10 is opened without shielding the recording sheet discharge port 9, and the recording sheet 7 can pass through. The recording sheet discharge port 9 is shielded by the shielding plate 10 over the whole opening section in the waiting state after the recording sheet 7 is discharged. |
