Patent ID: 7853163

Claim:
A fixing device for fixing a toner image formed on a recording medium, onto the recording medium, comprising: a fixing roller having a gear wheel, the fixing roller being driven to rotate about a predetermined axis of rotation under a driving force transmitted thereto via the gear wheel; a pressure roller disposed in pressure-contact with the fixing roller so as to be rotatable depending on a rotation of the fixing roller, the pressure roller holding and conveying a recording medium on which is formed a toner image in cooperation with the fixing roller in a nip region where the pressure roller and the fixing roller abut against each other; a driving section having a driving gear wheel engageable with the gear wheel of the fixing roller, for driving the fixing roller by rotating the driving gear wheel; and a control section for, after determining that conditions for acceleration including coincidence between a nip region-to-recording medium positional relationship and a predetermined acceleration-adapted positional relationship are fulfilled, effecting control of the driving section in a manner so as to increase a rotating speed of the driving gear wheel to allow the driving gear wheel to rotate at a rotating speed higher than a before-acceleration rotating speed over a predetermined high-speed rotating period.