Patent ID: 11886136
Assignee: BROTHER KOGYO KABUSHIKI KAISHA
Field: Optics (Instruments)
Classification: CPC G | IPC G

Claim 0:
1. An image forming apparatus comprising:
a transfer unit including:
a plurality of rollers; and
an endless belt stretched between the plurality of rollers and configured to convey a sheet in a conveyance direction, an upper surface of the endless belt serving as a conveyance surface; and

a process unit including:
a photosensitive drum provided above the endless belt in a gravitational direction, the process unit being configured to form an image on the sheet at a transfer nip between the photosensitive drum and the endless belt; and
a drum frame supporting the photosensitive drum, the drum frame including a first regulating portion located between the transfer nip and a downstream end of the conveyance surface in the conveyance direction, the first regulating portion facing the conveyance surface from above the conveyance surface in the gravitational direction, the first regulating portion being configured to contact the sheet that is conveyed on the conveyance surface,
the first regulating portion is a plate-like member including:
a first horizontal portion extending in a width direction perpendicular to the conveyance direction; and
a pair of first inclined portions extending from both ends of the first horizontal portion in the width direction, each of the pair of first inclined portions having one end adjacent to the first horizontal portion and an other end away from the one end in the width direction, each of the pair of first inclined portions being inclined to be closer to the endless belt from the one end toward the other end, the pair of first inclined portions being configured to contact both ends of the sheet in the width direction,

wherein the image forming apparatus is configured to form an image on a sheet having a first width in the width direction and on a sheet having a second width greater than the first width;
wherein a distance between the other end of each of the pair of first inclined portions in the width direction is larger than the first width;
wherein a size of the first horizontal portion in the width direction is smaller than the first width;
wherein the image forming apparatus further comprises:
a fixing device configured to thermally fix an image formed on the sheet, the fixing device including a heat roller and a pressure roller in contact with the heat roller to form a fixing nip for nipping the sheet; and
a second regulating portion provided between the first regulating portion and the fixing nip in the conveyance direction in a conveyance path of the sheet;

wherein the second regulating portion includes:
a second horizontal portion extending in the width direction; and
a pair of second inclined portions extending from both ends of the second horizontal portion in the width direction, each of the pair of second inclined portions having an inner end adjacent to the second horizontal portion and an outer end away from the inner end in the width direction, each of the pair of second inclined portions being inclined downward from the inner end toward the outer end, the pair of second inclined portions being configured to contact both ends of the sheet in the width direction,

wherein a distance between the outer end of each of the pair of second inclined portions in the width direction is larger than the second width;
wherein a size of the second horizontal portion in the width direction is smaller than the second width; and
wherein the size of the second horizontal portion in the width direction is larger than the distance between the other end of each of the pair of first inclined portions in the width direction.