An image forming apparatus.

摘要

An image forming apparatus comprises an image forming unit for forming and transferring an image of a document to a copy sheet, a fixing unit (19) including a fixing roller (191) for fixing the document image to the sheet while transporting the sheet, a heater (193) for the fixing roller, and a heater control unit (34) for turning the heater on and off at specified timings so as to establish and maintain the temperature of the fixing roller in a predetermined range whose upper limit is a fixing temperature. The copy sheet heated by the fixing roller has a temperature of about the predetermined fixing temperature while in transport, whereby the image transferred to the copy sheet is fixed thereto. A control unit (30) acts on the heater control unit (34) so that it controls the heater over the period during which a copying operation is completed. The heater control unit on-off controls the heater only during the copying operation. Accordingly, power consumed by the heater is reduced and an unwanted temperature increase within the apparatus can be avoided.