An image forming apparatus includes an image forming portion, a reversing portion configured to reverse the sheet received through a first feeding passage by feeding the sheet in a first direction and then in a second direction opposite to the first direction, a sheet feeding portion provided in a second feeding passage branching from the first feeding passage on a side upstream of the reversing portion with respect to the first direction, a first guiding surface forming the second feeding passage for guiding a first surface of the sheet fed by the feeding portion, and a second guiding surface for guiding a second surface, opposite from the first surface, of the sheet fed from the reversing portion in the second direction. The second guiding surface is movable with movement of the first guiding surface for opening the second feeding passage.

A sheet conveyance apparatus includes a first conveyance portion configured to convey a sheet, a second conveyance portion configured to convey the sheet, the second conveyance portion including an abutment portion configured to form a loop on the sheet by being abutted against a leading edge of a sheet conveyed by the first conveyance portion, a curved guide portion, which is curved, configured to guide the sheet conveyed by the first conveyance portion to the second conveyance portion, and a rotary member arranged downstream of the first conveyance portion and upstream of the second conveyance portion in a sheet conveyance direction, and configured to be driven to rotate by a surface of the sheet that is guided by the curved guide portion, the surface sliding against the curved guide portion.

An image forming system includes an image forming apparatus, an image reading apparatus, a connecting conveyance path that branches from a second main conveyance path of the image reading apparatus and joins a first sub conveyance path of the image forming apparatus, and configured to convey an original from the image reading apparatus to the image forming apparatus. The system controls conveyance of the original so that a first side becomes a side that faces an image forming unit if the first side of the original is designated as the image formation side or so that a second side becomes the side that faces the image forming unit if the second side of the original iFs designated as the image formation side.

An image forming apparatus includes: a sheet conveyance unit which includes a sheet conveyance path and conveys a sheet; a sheet detector which detects the sheet in the sheet conveyance path; a job acquiring unit which acquires a print job related to the sheet; an image forming unit which forms an image on the sheet; and a processor which controls the sheet conveyance unit to perform one of first sheet conveyance and second sheet conveyance, the first sheet conveyance being performed to convey the sheet in accordance with sheet information, the second sheet conveyance being performed to convey the sheet and discharge the sheet to outside in accordance with a result of detection, wherein when sheet conveyance is resumed after suspension, the processor controls the sheet conveyance unit to perform the second sheet conveyance on a remaining sheet.

An image forming apparatus includes an image forming unit, a paper loading base on which manual-feed paper is loaded, a manual-feed paper conveying unit, and a dustproof cover which covers the paper loading base being in the overhang state. The paper loading base has a lower end rotatably supported on one outer surface portion of the device main body, and is opened from an upper end thereof and disposed at a predetermined oblique angle or in a horizontal overhang state such that an overhang side becomes an upper side in an oblique direction. The manual-feed paper conveying unit is conveys the manual-feed paper on the paper loading base onto a paper conveyance path one by one. The dustproof cover includes a base which engages with the paper loading base, and an opening-and-closing cover which is rotatably connected to the base and is opened upwardly on the overhang side.

A sheet feeding apparatus includes a first drive roller and a second drive roller disposed downstream of the first drive roller and configured to rotate at a peripheral speed greater than a peripheral speed of the first drive roller. The first drive roller includes a drive shaft and a roller portion. The roller portion is configured to contact the sheet and is movable relative to the drive shaft in an axial direction and a rotation direction of the drive shaft. One of the drive shaft and the roller portion of the first drive roller includes a protrusion protruding toward the other one of the drive shaft and the roller portion. The other one of the drive shaft and the roller portion of the first drive roller includes a recessed portion. The recessed portion includes a peripheral wall that defines an opening such that the protrusion is positioned in the opening.

An image forming apparatus includes a photosensitive drum, a fixing unit including a fixing roller, a sheet ejection tray, a switchback roller, a re-feeding roller, a first frame, a second frame, a first motor, a first transmission mechanism, a second motor, and a second transmission mechanism. The switchback roller is configured to rotate in a forward direction to convey a sheet to the tray and in a reverse direction to convey the sheet back toward the photosensitive drum. The first motor and the first transmission mechanism are disposed to the first frame. The first transmission mechanism is configured to transmit the drive force from the first motor to the fixing roller. The second motor and the second transmission mechanism are disposed to the second frame. The second transmission mechanism is includes a clutch mechanism configured to intermittently transmit the drive force from the second motor to the re-feeding roller.

A medium transportation apparatus includes a transportation portion for transporting a medium; a first structure unit for forming a first transportation path to guide and transport the medium in a first direction from an upstream side in a medium transportation direction toward a downstream side in the medium transportation direction; and a second structure unit for forming an accommodation space to accommodate a part of the first structure unit. The first structure unit includes a first region disposed outside the accommodation space on the downstream side in the medium transportation direction and a second region disposed inside the accommodation space on the upstream side in the medium transportation direction.

An image forming apparatus includes: a reconveying unit including a reconveying roller; and a second transmission mechanism. The second transmission mechanism transmits a drive force to the reconveying roller and includes: an input gear; an output gear; an intermediate gear including first and second gears; and first and second swinging gears. The first toothless part of the first gear and the second toothless part of the second gear are provided at such a position that, when the intermediate gear is rotated by a drive force transmitted from the input gear through the second swinging gear while the second swinging gear meshes with the second toothed part of the second gear and the output gear meshes with the first toothed part of the first gear, the first toothless part reaches a position confronting the output gear and then the second toothless part reaches a position confronting the second swinging gear.

An image forming apparatus fixes a toner image onto a sheet by a fixer, and includes: a re-feeding path that normally conveys the sheet having passed through the fixer and guides the sheet toward the fixer; and a hardware processor that switches between first control to discharge the sheet having passed through the fixer toward a discharge destination and second control to re-feed the sheet having passed through the fixer to the fixer through the re-feeding path, depending on a type of an image which is a source of formation of the toner image.