A sheet processing apparatus includes a folding device to fold a sheet and a fold-enhancing device to press a folded portion of the sheet folded by the folding device to perform enhanced folding processing on the sheet whose trailing edge has exited the folding device.

A sheet processing apparatus includes an entry portion, a sheet conveyance path extending from the entry portion, a skew correction roller pair that contacts a leading edge of a sheet conveyed in a predetermined direction from the entry portion to correct skew of the sheet, and a receiving path. The skew correction roller pair conveys the skew-corrected sheet in a direction opposite the predetermined direction. The receiving path branches from the sheet conveyance path from the entry portion to the skew correction roller pair to receive the sheet conveyed in the direction opposite the predetermined direction.

An embodiment of this disclosure provides a folding apparatus configured to stack and fold a designated number of sheets at a time. The folding apparatus includes a conveyor configured to sequentially convey the designated number of sheets, a stacker configured to temporarily store a sheet conveyed by the conveyor to stack the designated number of sheets, a sheet folding device configured to fold the designated number of sheets at a time, and control circuitry. The control circuitry is configured to cause the sheet folding device to fold the stored sheet in response to an occurrence of a sheet jam upstream from the stacker in a direction of sheet conveyance, in processing the designated number of sheets.

A sheet processing includes a first conveyance path, a buffering portion, a second conveyance path, a conveyance roller pair, a supporting portion, a moving member, a regulating portion, and a processing unit. The buffering portion is configured to superimpose a first sheet and a second sheet on each other in a state of being offset from each other in a sheet conveyance direction. An offset amount, by which a leading end of the first sheet in the sheet conveyance direction projects downstream in the sheet conveyance direction with respect to a leading end of the second sheet in the sheet conveyance direction in a state before the first sheet and the second sheet are discharged onto the supporting portion, is larger than a distance from a sheet contact position of the moving member to the regulating portion in the sheet conveyance direction.

An apparatus and method for the post-processing of successively following, sequentially printed sheets, includes a conveyor, a folding table, a folding sword, a folding roller pair, at least one pressing-down mechanism, and a machine control that is operatively connected to the folding sword and the pressing-down mechanism. The pressing-down mechanism includes at least one mechanical braking element which acts in the region of the back edge onto the top side of the printed sheet to be positioned on the folding table. The stationary folding sword includes a compressed-air device with at least one outlet opening for compressed air which is focused onto a folding roller gap. The folding table forms a gathering device for at least two successively following printed sheets. A sensor, arranged in a region of the conveyor, is operatively connected to the machine control and functions to detect the printed sheets, transported with the conveyor.

A method of grouping sheet units, which belong together in sheet groups, a sheet stream comprising two superposed sheet units each by means of a grouping unit, a grouping unit for a sheet handling system, and a sheet handling system that allow a high processing speed and a high cycle efficiency of a sheet handling system are disclosed. A sheet unit can be held back in the grouping unit. Depending on whether the downstream subsequent sheet units transferred into the grouping unit belong to a sheet group, the held-back sheet unit can be released by itself and together with one or together with both downstream subsequent sheet units.

Disclosed is a post-processing apparatus couplable to an image forming apparatus. The post-processing apparatus comprises: a paper discharging roller to convey, from a conveying path, a first paper discharged from the image forming apparatus, to a standby path connected to the conveying path, and convey the first paper from the standby path and a second paper discharged from the image forming apparatus from the conveying path, to an intermediate loading part, in a state in which a leading end of the first paper toward the intermediate loading part protrudes more than a leading end of the second paper toward the intermediate loading part to process the first paper and the second paper.

A sheet processing apparatus includes conveyers to convey a sheet. The conveyers include a registration conveyer which a plurality of sheets is to sequentially contact and is configured to bend a preceding sheet contacting the registration conveyer toward a direction in which the preceding sheet does not obstruct an entry of a following sheet to the registration conveyer when the conveyers overlay and convey the plurality of sheets after the plurality of sheets sequentially contacts the registration conveyer.

A sheet processing apparatus includes a first conveyer to convey a sheet, a first folding device to fold the sheet and put a crease in the sheet, a second conveyer to convey the sheet folded by the first folding device, a second folding device to fold the sheet and put a crease in the sheet, and a guide. The first conveyer and the second conveyer are rotatable in reverse. The guide guides the sheet conveyed downstream from the first conveyer and the sheet conveyed downstream from the second conveyer.

A folding apparatus includes a folding device to fold a sheet bundle, an additional folding device, a conveyer, and control circuitry. The additional folding device includes a pressure roller disposed downstream from the folding device in a sheet conveyance direction and configured to press the sheet bundle after the folding device folds the sheet bundle and a sheet support member disposed opposite the pressure roller via the sheet bundle. The conveyer conveys the sheet bundle to a position at which the additional folding device presses the sheet bundle and hold the sheet bundle at the position. The control circuitry causes the additional folding device to perform additional folding processing on a first position of the sheet bundle, the conveyer to move the sheet bundle to a second position different from the first position, and the additional folding device to perform the additional folding processing at the second position again.