Abstract: A sheet processing apparatus includes a processing tray configured to stack a sheet to be processed, a sheet overlap unit configured to allow a sheet fed while the sheet to be processed is stacked on the processing tray, to be overlaid and made to wait, first and second bundle conveyance rollers configured to convey the sheet to the processing tray from the sheet overlap unit, and a sheet processing apparatus control unit configured to control an overlap operation in the sheet overlap unit, wherein the sheet processing apparatus control unit determines, based on sheet information relating to the sheet fed to the sheet overlap unit, whether a sheet to be then fed is overlaid on the sheet fed to the sheet overlap unit.

Abstract: A roller separating mechanism rotates an upper roller-moving cam and a lower roller-moving cam at the same time, and swings the upper roller arm plate and the lower roller arm plate such that a pair of folding rollers separate from each other. When the pair of folding rollers are to be abutted against each other, the upper roller arm plate and the lower roller arm plate are swung with different timing in a direction in which the pair of folding rollers abut against each other.

Abstract: A sheet processing apparatus capable of improving sheet processing performance and productivity is provided. While sheets are conveyed in a piled state toward a rear-end stopper, displacement is produced between the sheets by a pair of discharge rollers. Even if adhesion occurs between the sheets during conveyance thereof, the adhesion between the sheets can be removed before the sheets come into contact with the rear-end stopper.

Abstract: A current invention provides a sheet processing apparatus and an image forming apparatus capable of obtaining a sheet bundle which can be double-leaved and released without use of any binding device. A slit S to which a projection Pa provided at an end portion opposite to a side to be bound by a binding portion of a front cover P1 is formed in a back cover P3 of a sheet bundle PA by an insertion portion forming portion. Further, creases L1, L2 for inserting the projection Pa into the slit S while surrounding sheets P2 existing between the front cover P1 and the back cover P2 are formed in the back cover P3 of the sheet bundle PA by a crease forming portion.

Abstract: Provided is a shift transport device for transporting a sheet to a sheet transport direction upstream side of a sheet process tray and for shifting the sheet. The shift transport device offsets the sheet and the sheets are stacked on a sheet process tray. Then, the sheets stacked on the sheet process tray in a state of being offset are aligned by an aligning member.

Abstract: The present invention provides a sheet stacking apparatus which has a pair of lower discharge rollers which discharges a sheet, a processing tray which stacks the sheet discharged from the pair of lower discharge rollers, a trailing end stopper which aligns the trailing end portion in the conveying direction of the sheet bundle stacked on the processing tray, and pull-in paddles which drop the sheet discharged from the pair of lower discharge rollers on the processing tray and conveys the sheet to abut against the trailing end stopper where the pull-in paddles rotate at a first rotating speed so that the sheet discharged from the pair of lower discharge rollers is dropped on the processing tray and the pull-in paddles rotate at a second rotating speed, slower than the first rotating speed, so that the sheet abuts against the trailing end stopper.

Abstract: A sheet processing apparatus includes an aligning member and a shift conveying unit. The aligning member is movable in a width direction perpendicular to a sheet conveying direction and presses a sheet stack loaded on a sheet processing tray so as to align the sheet stack in the width direction. The unit is provided on the upstream side of the tray and conveys a sheet, shifting the sheet in the width direction. Being shifted by the unit, sheets are loaded at first and second loading positions on the tray. When sheets are loaded at the first loading position, the aligning member is moved to a first standby position corresponding to the first loading position in advance. When sheets are loaded at the second loading position, the aligning member is moved in advance to a second standby position corresponding to the second loading position.

Abstract: When a sheet bundle is being conveyed by any one pair of plural pairs of rollers independently movable toward and away from the bundle sheet, before the bound portion of the sheet bundle passes the pair of rollers, the pair of rollers on the downstream side nearest to the bound portion are separated from the sheet bundle, and the pairs of rollers more downstream than that pair convey the sheet bundle. Thereby, it happens less often that the pairs of rollers gather the air collected between adjacent ones of the sheets of the sheet bundle to the bound portion to thereby cause a slack to the sheets, and the occurrence of wrinkles or twists in the sheet bundle can be reduced. Also, the pair of rollers are separated from the sheet bundle before the bound portion passes the pair of rollers, whereby it happens less often that the pair of rollers are damaged by the bound portion, and the sheet bundle can be conveyed smoothly.

Abstract: When a sheet bundle is being conveyed by any one pair of plural pairs of rollers independently movable toward and away from the bundle sheet, before the bound portion of the sheet bundle passes the pair of rollers, the pair of rollers on the downstream side nearest to the bound portion are separated from the sheet bundle, and the pairs of rollers more downstream than that pair convey the sheet bundle. Thereby, it happens less often that the pairs of rollers gather the air collected between adjacent ones of the sheets of the sheet bundle to the bound portion to thereby cause a slack to the sheets, and the occurrence of wrinkles or twists in the sheet bundle can be reduced. Also, the pair of rollers are separated from the sheet bundle before the bound portion passes the pair of rollers, whereby it happens less often that the pair of rollers are damaged by the bound portion, and the sheet bundle can be conveyed smoothly.

Abstract: A bundle discharge roller pair is made to rotate backward in a holding state in which the sheets are held between the bundle discharge roller pair, and, at the same time, the upper bundle discharge roller of the pair is separated from the lower bundle discharge roller of the pair. The released sheets slide down on the inclined processing tray at a return velocity Vb; and are made to run into the rear end stopper for aligning. The return velocity Vb may be controlled according to the reverse-rotational speed of the bundle discharge roller pair and is set at a low velocity, when it is found that, for example, the size of the sheet is large, and the return velocity Vb is increased in the case of coated paper with a large coefficient of friction.

Abstract: A sheet processing system comprises a plurality of sheet processing devices, a primary sheet conveyance path, a secondary sheet conveyance path, and a controller which controls the sheet processing devices. The controller uses the primary sheet conveyance path to execute one job, and uses the secondary sheet conveyance path to execute another job in parallel with that one job.

Abstract: A sheet processor includes a holding unit for holding a folded batch of sheets, a pressing member for pressing against a folded portion of the batch of sheets, a nipping member for nipping portions of the batch adjacent to the folded portion so as to nip the batch of sheets from opposite directions, and a casing for supporting the pressing member and the nipping member.

Abstract: A sheet processing apparatus includes an aligning member and a shift conveying unit. The aligning member is movable in a width direction perpendicular to a sheet conveying direction and presses a sheet stack loaded on a sheet processing tray so as to align the sheet stack in the width direction. The unit is provided on the upstream side of the tray and conveys a sheet, shifting the sheet in the width direction. Being shifted by the unit, sheets are loaded at first and second loading positions on the tray. When sheets are loaded at the first loading position, the aligning member is moved to a first standby position corresponding to the first loading position in advance. When sheets are loaded at the second loading position, the aligning member is moved in advance to a second standby position corresponding to the second loading position.

Abstract: Provided is a shift transport device for transporting a sheet to a sheet transport direction upstream side of a sheet process tray and for shifting the sheet. The shift transport device offsets the sheet and the sheets are stacked on a sheet process tray. Then, the sheets stacked on the sheet process tray in a state of being offset are aligned by an aligning member.

Abstract: A sheet processing apparatus has: a plurality of conveying paths which convey sheets; and front and back aligning members which perform width alignment in the direction which crosses the sheet conveying direction of the sheets conveyed from the conveying paths. Standby positions when the front and back aligning members approach side edges of the sheets from the standby positions and perform the width alignment of the sheets at the width aligning position are made different every sheet on the basis of discharge position information of the sheets to the plurality of conveying paths.

Abstract: A sheet processing device includes a pair of gripping rollers which can grip and convey a sheet bundle in a booklet-like form, a pressing roller which presses and flattens the folded back portion of the sheet bundle gripped by the gripping rollers, and a control unit which performs rotation control on the pair of gripping rollers. The control unit controls the gripping rollers so as to stop when the folded back portion of the sheet bundle protrudes from the rollers by a predetermined amount. The pressing roller flattens down the protruding folded back portion when the gripping rollers are stopped by the control unit and is in the state of gripping the sheet bundle.

Abstract: The present invention provides a sheet stacking apparatus which has a pair of lower discharge rollers which discharges a sheet, a processing tray which stacks the sheet discharged from the pair of lower discharge rollers, a trailing end stopper which aligns the trailing end portion in the conveying direction of the sheet bundle stacked on the processing tray, and pull-in paddles which drop the sheet discharged from the pair of lower discharge rollers on the processing tray and conveys the sheet to abut against the trailing end stopper where the pull-in paddles rotate at a first rotating speed so that the sheet discharged from the pair of lower discharge rollers is dropped on the processing tray and the pull-in paddles rotate at a second rotating speed, slower than the first rotating speed, so that the sheet abuts against the trailing end stopper.

Abstract: A sheet processing apparatus includes an aligning member and a shift conveying unit. The aligning member is movable in a width direction perpendicular to a sheet conveying direction and presses a sheet stack loaded on a sheet processing tray so as to align the sheet stack in the width direction. The unit is provided on the upstream side of the tray and conveys a sheet, shifting the sheet in the width direction. Being shifted by the unit, sheets are loaded at first and second loading positions on the tray. When sheets are loaded at the first loading position, the aligning member is moved to a first standby position corresponding to the first loading position in advance. When sheets are loaded at the second loading position, the aligning member is moved in advance to a second standby position corresponding to the second loading position.

Abstract: The sheet processing apparatus is equipped with a process tray on which sheets conveyed are stacked, a return belt which moves the sheets stacked on the process tray, a trailing edge stopper which receives an end portion of the sheets moved by the return belt, and a conveyance assist roller which comes into contact with the sheets on the upstream side of the return belt with respect to the sheet moving direction and imparts a load to the movement of the sheets. The return belt moves the sheets to which a load has been imparted by the conveyance assist roller and causes them to be abutted on the trailing edge stopper.

Abstract: Provided is a shift transport device for transporting a sheet to a sheet transport direction upstream side of a sheet process tray and for shifting the sheet. The shift transport device offsets the sheet and the sheets are stacked on a sheet process tray. Then, the sheets stacked on the sheet process tray in a state of being offset are aligned by an aligning member.