CONTACT AND SEPARATION DEVICE, FIXING DEVICE, AND IMAGE FORMING APPARATUS

• Main Authors: IMADA TAKAHIRO, SAITO SEIJI, OKAMOTO JUN, TAKAGI HIROTADA, IKEDA TAMOTSU, SASAKI YOSHIKUNI
• Format: Patent
• Language: English; Japanese
• Published: 19.01.2023
• Subjects: CINEMATOGRAPHY; ELECTROGRAPHY; ELECTROPHOTOGRAPHY; HOLOGRAPHY; MAGNETOGRAPHY; PHOTOGRAPHY; PHYSICS

To provide a contact and separation device that can accurately locate a contact and separation member at a target position, a fixing device, and an image forming apparatus.SOLUTION: A contact and separation mechanism being a contact and separation device comprises: a pressure spring being an urging member; and a pressure lever being a pushing-in member that pushes in a pressure roller being a contact and separation member allowed to be in contact with and separated from a fixing roller being a member to be contacted, to be brought into contact with the fixing roller with urging force of the urging member. The contact and separation mechanism further comprises a cam member 41 that pushes in the pressure lever 31 in a direction opposite to the direction to push in the pressure roller. A cam contact surface 131d of the pressure lever in contact with the cam member 41 is a concave surface having a smaller maximum curvature than that of a cam surface 41a of the cam member 41 and having a larger minimum curvature than that of the cam surface 41a.SELECTED DRAWING: Figure 10 【課題】狙いの位置に精度よく接離部材を位置させることができる接離装置、定着装置および画像形成装置を提供する。【解決手段】接離装置たる接離機構は、付勢部材たる加圧バネと、付勢部材の付勢力により、被当接部材たる定着ローラに対して接離可能に構成された接離部材たる加圧ローラを定着ローラに当接するように押し込む押し込み部材たる加圧レバーとを備えている。また、接離機構は、加圧ローラを押し込む方向とは逆方向に加圧レバー３１を押し込むカム部材４１を備えている。加圧レバーのカム部材４１が当接するカム当接面１３１ｄを、カム部材４１のカム面４１ａの最大曲率よりも小さく、カム面４１ａの最小曲率よりも大きい凸曲面とした。【選択図】図１０