Fixing device that controls rotation speed of press roller, according to temperature of fixing element at start of job, type of recording sheet, ambient temperature, and elapsed time after start of paper feed, and image forming apparatus

摘要

A fixing device includes: a fixing element; a heat source heating the fixing element; a press roller pressed against the fixing element, to form with the fixing element a nip region where a recording sheet passes; a driver device rotating the press roller; and a controller controlling the heat source to set a temperature of the fixing element to a predetermined target temperature, and controlling the driver device to set a rotation speed of the press roller to a predetermined target rotation speed. The controller determines the target rotation speed by adding a correction value to a normal rotation speed, based on the temperature of the fixing element at start of job, a type of the recording sheet, ambient temperature, and elapsed time from start of paper feed, and sets the rotation speed of the press roller to the target rotation speed.