FIXING DEVICE AND IMAGE FORMING APPARATUS

• Main Authors: IKEBUCHI YUTAKA, IWATANI NAOKI, SHIMOKAWA TOSHIHIKO, ARAI YUJI, SEKI TAKAYUKI, TAMAKI TOSHITARO, YAMAGUCHI YOSHINORI
• Format: Patent
• Language: English; Japanese
• Published: 27.04.2017
• Subjects: CINEMATOGRAPHY; ELECTROGRAPHY; ELECTROPHOTOGRAPHY; HOLOGRAPHY; MAGNETOGRAPHY; PHOTOGRAPHY; PHYSICS

PROBLEM TO BE SOLVED: To provide a fixing device that can effectively suppress an increase in temperature at the ends due to a difference in width between recording media by using the minimum number of heaters, so as to handle recording media having various widths.SOLUTION: There is provided a fixing device 20 comprising an endless rotatable fixing member having flexibility, a heat source 35 that heats the fixing member, and a pressure member that is in pressure contact with the fixing member, and passing a recording medium carrying an unfixed image through a nip part between the fixing member and pressure member to fix the image, the fixing device including a shield member 43 that is arranged between an inner surface of the fixing member and the heating source, rotatable in the circumferential direction of the fixing member, and shields radiation heat emitted from the heat source to the fixing member, wherein the shield member rotates in one direction and the other direction from a reference position where the length of a portion of the heat source not covered by the shield member substantially corresponds to the width of a recording medium that is frequently used.SELECTED DRAWING: Figure 7 【課題】最小限の数のヒータを用いて、記録媒体幅の違いによる端部温度上昇を効果的に抑制し、様々な幅の記録媒体に対応することができる定着装置を提供する。【解決手段】可撓性を有する無端状の回転可能な定着部材と、定着部材を加熱する加熱源３５と、定着部材に圧接する加圧部材とを備え、定着部材と加圧部材の間のニップ部に未定着画像を担持した記録媒体を通過させて画像の定着を行なう定着装置２０において、定着部材の内面と加熱源の間に配置され、定着部材の周方向に回転可能であり、加熱源から定着部材へ放射される輻射熱を遮蔽する遮蔽部材４３を備え、遮蔽部材は、遮蔽部材により覆われていない部分の加熱源の長さが使用頻度の高い記録媒体幅に略対応する基準位置から、一方向及び他方向に回転する。【選択図】図７