# US 2024/0201623 A1 · Fixing unit and image forming apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2024/0201623 A1 - Document ID: US20240201623A1 - Status: Published application - Kind: A1 - Application number: 18/526,138 - Filed: 2023-12-01 - Published: 2024-06-20 - Earliest claimed: 2022-12-16 - Assignees: Canon Kabushiki Kaisha - Applicants: Canon Kabushiki Kaisha - Inventors: KOHEI WAKATSU; TSUGUHIRO YOSHIDA; KAZUHIRO DODA; TOSHIYUKI WATANABE - Web page: https://patentgrep.com/patent/US20240201623A1 ## CPC - G03G 15/2053: {Structural details of heat elements, e.g. structure of roller or belt, eddy current, induction heating} - G03G 15/2064: {combined with pressure} - G03G 2215/2025: the fixing nip having a rotating belt support member opposing a pressure member - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY ## Abstract A fixing unit includes a film, a nip forming member, a heating unit, a rotary member arranged to sandwich the film together with the nip forming member, and an end portion regulating member configured to be in sliding contact with the film and to regulate an end portion of the film in the longitudinal direction. The end portion regulating member includes a first surface facing an inner surface of the film, a second surface facing an end face of the film in the longitudinal direction, and a third surface facing an outer surface of the film and configured to regulate the end portion of the film from deforming in a manner separating from the first surface. An entirety of the third surface is disposed on an upstream side of a center position of the nip portion in a conveyance direction of the recording material in the nip portion. ## Claims ### Claim 1 A fixing unit comprising: a film having a tubular shape and extending in a longitudinal direction; a nip forming member arranged in an interior space of the film; a heating unit configured to heat the film; a rotary member arranged to sandwich the film together with the nip forming member, the rotary member being configured to form a nip portion between the nip forming member and the rotary member and to nip a recording material with the film at the nip portion to convey the recording material; and an end portion regulating member configured to be in sliding contact with the film and to regulate an end portion of the film in the longitudinal direction, wherein the end portion regulating member includes a first surface facing an inner surface of the film, a second surface facing an end face of the film in the longitudinal direction, and a third surface facing an outer surface of the film and configured to regulate the end portion of the film from deforming in a manner separating from the first surface, and wherein an entirety of the third surface is disposed on an upstream side of a center position of the nip portion in a conveyance direction of the recording material in the nip portion. ### Claim 2 (depends on 1) The fixing unit according to claim 1, wherein the end portion regulating member is configured to permit the end portion of the film to deform in a manner separating from the first surface on a downstream side of the center position of the nip portion in the conveyance direction of the recording material. ### Claim 3 (depends on 1) The fixing unit according to claim 1, wherein at least at a portion of the third surface, a distance between the first surface and the third surface is four times a thickness of the film or less. ### Claim 4 (depends on 1) The fixing unit according to claim 1, wherein a distance between the first surface and the third surface differs according to a position in a direction of rotation of the film, and wherein the distance is smallest at a position of a most upstream portion of the first surface in the conveyance direction of the recording material. ### Claim 5 (depends on 4) The fixing unit according to claim 4, wherein, a portion of the third surface including a starting end of the third surface in the direction of rotation of the film is formed such that the distance between the first surface and the portion of the third surface decreases toward a downstream side in the direction of rotation. ### Claim 6 (depends on 4) The fixing unit according to claim 4, wherein a portion of the third surface including a terminal end of the third surface in the direction of rotation of the film is formed such that the distance between the first surface and the portion of the third surface increases toward a downstream side in the direction of rotation. ### Claim 7 (depends on 1) The fixing unit according to claim 1, wherein the third surface extends in parallel with the first surface. ### Claim 8 (depends on 1) The fixing unit according to claim 1, wherein the third surface is inclined with respect to the first surface such that the third surface recedes further away from the first surface at a position closer to a center of the film in the longitudinal direction. ### Claim 9 (depends on 8) The fixing unit according to claim 8, wherein an inclination angle of the third surface to the first surface differs according to a position in a direction of rotation of the film, and wherein the inclination angle is smallest at a position of a most upstream portion of the first surface in the conveyance direction of the recording material. ### Claim 10 (depends on 1) The fixing unit according to claim 1, wherein a protruded length of the third surface in the longitudinal direction with respect to the second surface is shorter than a protruded length of the first surface in the longitudinal direction with respect to the second surface. ### Claim 11 A fixing unit comprising: a film having a tubular shape and extending in a longitudinal direction; a nip forming member arranged in an interior space of the film; a heating unit configured to heat the film; a rotary member arranged to sandwich the film together with the nip forming member, the rotary member being configured to form a nip portion between the nip forming member and the rotary member and to nip a recording material with the film at the nip portion to convey the recording material; and an end portion regulating member configured to be in sliding contact with the film and to regulate an end portion of the film in the longitudinal direction, wherein the end portion regulating member includes a first surface facing an inner surface of the film, a second surface facing an end face of the film in the longitudinal direction, and a third surface facing an outer surface of the film and configured to regulate the end portion of the film from deforming in a manner separating from the first surface, wherein the third surface is disposed on an upstream side and on a downstream side of a center position of the nip portion in a conveyance direction of the recording material in the nip portion, and wherein a distance between the first surface and the third surface at a position of a most upstream portion of the first surface in the conveyance direction is smaller than a distance between the first surface and the third surface at a position of a most downstream portion of the first surface in the conveyance direction. ### Claim 12 A fixing unit comprising: a film having a tubular shape and extending in a longitudinal direction; a nip forming member arranged in an interior space of the film; a heating unit configured to heat the film; a rotary member arranged to sandwich the film together with the nip forming member, the rotary member being configured to form a nip portion between the nip forming member and the rotary member and to nip a recording material with the film at the nip portion to convey the recording material; and an end portion regulating member configured to regulate an end portion of the film in the longitudinal direction, wherein the end portion regulating member includes a first surface facing an inner surface of the film, and a second surface facing an end face of the film in the longitudinal direction, wherein the second surface includes an inclined portion that is inclined such that an angle between the first surface and the inclined portion of the second surface is an acute angle, and that is configured to regulate the end portion of the film in the longitudinal direction from deforming in a manner separating from the first surface, and wherein an entirety of the inclined portion is disposed on an upstream side of a center position of the nip portion in a conveyance direction of the recording material in the nip portion. ### Claim 13 (depends on 12) The fixing unit according to claim 12, wherein the inclined portion is disposed on an upstream side and a downstream side of a center portion of the nip portion in the conveyance direction of the recording material in the nip portion, and wherein an angle between the inclined portion and the first surface at a position of a most upstream portion of the first surface in the conveyance direction is smaller than an angle between the inclined portion and the first surface at a position of a most downstream portion of the first surface in the conveyance direction. ### Claim 14 (depends on 12) The fixing unit according to claim 12, wherein an angle between the inclined portion and the first surface differs according to a position in a direction of rotation of the film, and wherein the angle is smallest at a position of a most upstream portion of the first surface in the conveyance direction of the recording material. ### Claim 15 (depends on 12) The fixing unit according to claim 12, wherein the end portion regulating member includes a non-inclined portion of the second surface where the inclined portion is not provided, and wherein the end portion regulating member is arranged in a posture in which the non-inclined portion is closer to a center of the film in the longitudinal direction at a more downstream position in the conveyance direction of the recording material. ### Claim 16 (depends on 1) The fixing unit according to claim 1, wherein the heating unit is a heater held by the nip forming member and configured to generate heat in a case where an electric current is supplied, and wherein the fixing unit is configured to heat an image on the recording material by using the film heated by the heater. ### Claim 17 (depends on 1) An image forming apparatus comprising: an image forming unit configured to form an image on a recording material; and the fixing unit according to claim 1 configured to fix the image to the recording material.