| 摘要 |
PROBLEM TO BE SOLVED: To provide a fixing device which is capable of obtaining stable fixability by eliminating temperature unevenness in the longitudinal direction of a cylindrical rotary member rotated in a contact state with a nip forming member.SOLUTION: The fixing device includes a nip forming member 55, a cylindrical rotary member 51 rotated in a contact state with the nip forming member, a heating element 63 heating the rotary member from the inner peripheral surface side of the rotary member with radiant heat, and a backup member 52 forming a nip part N in cooperation with the nip forming member through the rotary member and heats and fixes an unfixed toner image on a recording material, while holding and conveying the recording material P carrying the unfixed toner image T, in the nip part. The nip forming member is formed so that the cross-section of a surface 55a in the longitudinal direction orthogonal to a recording material conveyance direction on the side of a contact surface with the rotary member is shaped to be a curved cross-section smoothly projected from both ends in the longitudinal direction of the nip forming member toward the central part in the longitudinal direction. |
