An image forming apparatus includes an image forming portion, an oblique movement correcting portion including a first registration roller pair and a first moving portion, a reversing portion, and a re-feeding portion. The reversing portion includes a reversing roller pair and a second moving portion. The re-feeding portion includes a second registration roller pair. When an image is formed on a second surface of a sheet opposite from a first surface of the sheet, a side end position of the sheet is corrected by the second moving portion and oblique movement of the sheet is corrected, and then the side end position of the sheet is corrected again by the first moving means and the sheet is fed to the image forming portion.

In an image forming apparatus capable of turning over a sheet to form images on both sides of the sheet, when duplex printing is executed successively on three or more sheets, a controller causes a first sheet conveyed from an image forming unit and a second sheet conveyed from the image forming unit to be guided into a first path by positioning a guide member in a first position, and then conveyed into a third path by a first roller, and causes a third and subsequent sheets conveyed from the image forming unit to be guided into a second path by positioning the guide member in a second position, and then conveyed into the third path by a second roller.

An image forming apparatus includes an image forming engine, a re-conveyance path configured to guide a sheet, on which an image is formed by the image forming engine, to be switched back and re-conveyed toward the image forming engine. The apparatus also includes a discharge tray, and a discharge path configured to guide the sheet in a sheet discharge direction toward the discharge tray. A stack lever is configured to contact a top surface of the sheet on the discharge tray and press the sheet toward the discharge tray. A guide member is configured to form a part of the re-conveyance path, extend up to a position downstream of the stack lever in the sheet discharge direction above the stack lever, and guide the sheet being conveyed along the re-conveyance path, between the guide member and the stack lever.

Disclosed is a post-processing apparatus configured to be coupled to an image forming apparatus or another post-processing apparatus. The post-processing apparatus includes: a post-processing unit that performs post-processing to a sheet that is conveyed; and a standby path arranged on an upstream side or a downstream side of the post-processing unit and capable of holding the sheet. The post-processing unit performs the post-processing in a state in which the sheet is partly in the standby path.

A sheet conveying apparatus configured to convey a sheet includes a reversing portion, a reversing retraction portion provided in the reversing portion, a conveyance portion, a guide member provided in the reversing retraction portion, and a fan provided in the conveyance portion. The reversing portion conveys the sheet in a first direction and then a second direction opposite to the first direction. The reversing retraction portion temporarily retracts the sheet conveyed in the first direction. The conveyance portion has a conveyance path through which the sheet conveyed in the second direction passes and configured to convey the sheet. The guide member guides one surface of the sheet. The fan blows air toward the sheet guided by the guide member and is disposed to blow the air of the conveyance path in the conveyance portion toward the reversing retraction portion and along the guide member in the first direction.

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 apparatus includes an image forming portion, an oblique movement correcting portion including a first registration roller pair and a first moving portion, a reversing portion, and a re-feeding portion. The reversing portion includes a reversing roller pair and a second moving portion. The re-feeding portion includes a second registration roller pair. When an image is formed on a second surface of a sheet opposite from a first surface of the sheet, a side end position of the sheet is corrected by the second moving portion and oblique movement of the sheet is corrected, and then the side end position of the sheet is corrected again by the first moving means and the sheet is fed to the image forming portion.

In an image forming apparatus capable of turning over a sheet to form images on both sides of the sheet, when duplex printing is executed successively on three or more sheets, a controller causes a first sheet conveyed from an image forming unit and a second sheet conveyed from the image forming unit to be guided into a first path by positioning a guide member in a first position, and then conveyed into a third path by a first roller, and causes a third and subsequent sheets conveyed from the image forming unit to be guided into a second path by positioning the guide member in a second position, and then conveyed into the third path by a second roller.

An image forming apparatus includes an image forming engine, a re-conveyance path configured to guide a sheet, on which an image is formed by the image forming engine, to be switched back and re-conveyed toward the image forming engine, a discharge tray, a discharge path configured to guide the sheet in a sheet discharge direction toward the discharge tray, a stack lever configured to contact a top surface of the sheet on the discharge tray and press the sheet toward the discharge tray, and a guide member configured to form a part of the re-conveyance path, extend up to a position downstream of the stack lever in the sheet discharge direction above the stack lever, and guide the sheet being conveyed along the re-conveyance path, between the guide member and the stack lever.

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.