FIXING DEVICE AND IMAGE FORMING APPARATUS

• Main Authors: TAKATSUKA RYO, KATO KOJI
• Format: Patent
• Language: English; Japanese
• Published: 23.01.2020
• Subjects: CINEMATOGRAPHY; ELECTROGRAPHY; ELECTROPHOTOGRAPHY; HOLOGRAPHY; MAGNETOGRAPHY; PHOTOGRAPHY; PHYSICS

To provide a fixing device that controls the temperature of a heating roller with a plurality of divided heaters, and a method for appropriately managing the temperature of the heating roller in switching from a medium with a narrow width to temperature control for printing a medium with a wide width.SOLUTION: A fixing device comprises: a fixing belt; a backup roller that forms a nip part with the belt; heaters 82, 83R, 83L, 84R, 84L that are arranged in plurality inside the fixing belt and in a width direction thereof and each heat an area of the fixing belt opposite thereto; thermistors on the back of the heaters 75 to 77 that detect temperatures of the heaters; and energization drive control units 101, 103 to 106 that control heating by the heaters. When an image forming apparatus sequentially prints recording sheets with different widths, before printing a recording sheet with a larger width after a recording sheet with a narrower width, the energization drive control unit at least provides a temperature preparation period for independently controlling the temperature of heaters that do not face a paper feed area of the recording sheet with a narrower width.SELECTED DRAWING: Figure 3 【課題】加熱ローラを、複数に分割されたヒータにより温度制御する定着装置では、幅狭の媒体から、幅広の媒体を印刷する温度制御に切り替える際に、加熱ローラの適切な温度管理を行う方法を提供する。【解決手段】定着ベルトと、これとニップ部を形成するバックアップローラと、定着ベルトの内側でその幅方向に複数配列され、それぞれが定着ベルトの対向する領域を加熱するヒータ８２、８３Ｒ、８３Ｌ、８４Ｒ、８４Ｌと、これらのヒータ温度を検出するヒータ裏サーミスタ７５〜７７と、各ヒータを加熱制御する通電駆動制御部１０１，１０３〜１０６とを備え、通電駆動制御部は、幅の異なる記録用紙を前後して印刷する際に、より幅の狭い記録用紙からより幅の広い記録用紙を印刷する前に、少なくとも、より幅の狭い記録用紙の通紙領域に対向しないヒータを独立に温度制御する温度準備期間を設ける。【選択図】図３