IMAGE FORMING APPARATUS AND METHOD OF CONTROLLING TEMPERATURE OF FIXING APPARATUS

• Main Authors: HAYASHI HIDEAKI, OTSUKA YUTAKA
• Format: Patent
• Language: English; Japanese
• Published: 23.03.2015
• Subjects: CINEMATOGRAPHY; ELECTROGRAPHY; ELECTROPHOTOGRAPHY; HOLOGRAPHY; MAGNETOGRAPHY; PHOTOGRAPHY; PHYSICS

PROBLEM TO BE SOLVED: To provide an image forming apparatus configured to prevent reduction in temperature while reducing the influence on the service life of a fixing apparatus.SOLUTION: An image forming apparatus includes: a fixing apparatus which forms a nip between a first rotation body containing at least one heating element in order to generate and output a printed matter on the basis of a print job, and a second rotation body in pressure contact with the first rotation body, to fix a toner image to a sheet introduced from a transfer unit to the nip; and a control circuit for adjusting a surface temperature of the first rotation body by controlling power to be supplied to the heating element. The control circuit acquires the time elapsed from the end of a previous print job and the number of sheet printed per unit time immediately before executing a current print job, and reduces the surface temperature of the first rotation body as the obtained elapsed time is shorter and the number of printed sheet is larger, to prevent reduction in surface temperature of the first rotation body when the sheet passes through the nip (S06-S09). 【課題】定着装置の寿命への影響がより少ない温度低下抑制が可能な画像形成装置を提供すること。【解決手段】画像形成装置は、印刷ジョブに基づき印刷物を生成し出力するために、少なくとも一つの発熱体を内蔵する第一回転体と、第一回転体と圧接する第二回転体とでニップを形成し、転写部からニップに導入されたシートにトナー像を定着させる定着装置と、発熱体への電力供給を制御することで第一回転体の表面温度を調整する制御回路と、を備えている。制御回路は、前回の印刷ジョブ終了からの経過時間と、今回の印刷ジョブ実行直前の単位時間当たりの印刷枚数と、を取得し、取得した経過時間が短くかつ印刷枚数が多い程、第一回転体の表面温度を低くして、ニップをシートが通過することに起因する第一回転体の表面温度の低下を抑制する（Ｓ０６〜Ｓ０９）。【選択図】図３