US 12,326,687 B2
Image forming apparatus
Kimio Takeuchi, Nagoya (JP); and Shinichi Hatakeyama, Nagoya (JP)
Assigned to BROTHER KOGYO KABUSHIKI KAISHA, Nagoya (JP)
Filed by BROTHER KOGYO KABUSHIKI KAISHA, Nagoya (JP)
Filed on Sep. 14, 2023, as Appl. No. 18/466,959.
Claims priority of application No. 2022-152960 (JP), filed on Sep. 26, 2022.
Prior Publication US 2024/0103435 A1, Mar. 28, 2024
Int. Cl. G03G 15/20 (2006.01); G03G 21/20 (2006.01)
CPC G03G 21/206 (2013.01) [G03G 15/2017 (2013.01)] 12 Claims
OG exemplary drawing
 
1. An image forming apparatus, comprising:
a photosensitive drum on which a toner image is to be formed; and
a fuser configured to fix the toner image transferred from the photosensitive drum onto a conveyed sheet, the fuser including:
a heating rotating member;
a pressing rotating member configured to nip the sheet together with the heating rotating member; and
an upper frame covering the heating rotating member,
wherein the upper frame includes:
an upper first rib extending in the sheet conveying direction downstream of the heating rotating member in the sheet conveying direction;
an upper second rib adjacent to the upper first rib in a width direction perpendicular to the sheet conveying direction and extending in the sheet conveying direction;
a first conveying roller configured to convey the sheet; and
a second conveying roller configured to face the first conveying roller, the first conveying roller and the second conveying roller configured to nip the sheet at a nip point therebetween,
wherein the upper first rib includes:
a first guide surface configured to guide an upper surface of the conveyed sheet; and
a separation surface located downstream of the first guide surface in the sheet conveying direction and at a position farther from the nip point than the first guide surface in a direction perpendicular to the sheet conveying direction and the width direction,
wherein the upper second rib includes a second guide surface configured to guide the upper surface of the conveyed sheet,
wherein the second guide surface is located downstream of the first guide surface in the sheet conveying direction, and
wherein a distance between the nip point and the second guide surface in the direction perpendicular to the sheet conveying direction and the width direction is smaller than a distance between the nip point and the separation surface, and
wherein the fuser further include s a lower frame include:
a pair of lower first ribs extending in the sheet conveying direction downstream of the heating rotating member in the sheet conveying direction and being arranged in the width direction, the pair of lower first ribs being configured to guide a lower surface of the conveyed sheet; and
a lower second rib located between the lower first ribs in the width direction and having a length in the sheet conveying direction shorter than a length in the sheet conveying direction of the lower first ribs,
wherein the second rib overlaps with a downstream end portion of the lower first ribs in the conveying direction.