The present invention is to provide a configuration capable of stably conveying a sheet irrespective of the basis weight of the sheet. A pair of regulating guides is disposed on both sides of a conveying belt in a sheet width direction Y, each having a support surface that supports an end edge in the width direction of the sheet conveyed while being nipped by the conveying belt and balls and a guide surface that faces the end edge of the sheet in the width direction. Each of the pair of regulating guides is movable to a first guide position at which the end edge of the sheet in the width direction is supported by the support surface and guided by the guide surface and to a second guide position at which the end edge of the sheet in the width direction is supported by the support surface.

The apparatus is capable of handling sheets of various lengths while suppressing an increase in apparatus size, wherein each of a pair of regulating guides is movable to a guide position at which an end edge of a sheet in a sheet width direction can be guided by a guide surface and to a retracting position retracting further away from the sheet width direction end edge than the guide position. For sheets S1 and S2 each having a first sheet length, the pair of regulating guides is made to reach the guide position from the retracting position in a state where the front end of the sheet is located between upstream and downstream ends of the guide surface. For a sheet S3 having a second sheet length that is longer than the first length, the pair of regulating guides is made to reach the guide position from the retracting position.

A sheet discharge device includes: a sheet discharge portion; a sheet stacking portion having a sheet stacking surface for stacking a sheet discharged from the sheet discharge portion; and a stopper in the sheet stacking portion against which, for alignment, the leading end of the sheet discharged from the sheet discharge portion is thrust. The stopper has a support portion, a restricting portion, and an urging mechanism. The restricting portion is supported pivotally on a pivot shaft on the support portion, and is arranged either in a retracted position to lie flat substantially horizontally along the sheet stacking surface or in a restricting position to stand upright substantially vertically to the sheet stacking surface. The urging mechanism urges the restricting portion, when in retracted position, in a direction from restricting position to retracted position and, when in restricting position, in a direction from retracted position to restricting position.

An example stacking system comprises a stacking member movable between a first position in which the stacking member is configured to partially support a first stack of printed substrates, and a second position in which the stacking member is disengaged from the first stack. A receptacle positioned below the stacking member is configured to hold a second stack of printed substrates. A controller is configured to cause the stacking member to move between the first position and the second position when the first stack satisfies a criterion, thereby depositing the first stack into the receptacle on top of the second stack.

A sheet stacker includes a pair of sheet holders, a sheet leading-edge aligner, a sheet stacking member, and control circuitry. A downstream side of the pair of sheet holders in a conveyance direction of a conveyed sheet is lowered along the conveyance direction. Each one of the pair of sheet holders is movable in an orthogonal direction to the conveyance direction. The pair of sheet holders hold both side-end portions of the sheet in the orthogonal direction. The sheet stacking member is disposed below the pair of sheet holders. A downstream side of the sheet stacking member in the conveyance direction is lowered along the conveyance direction. The sheet stacking member stacks the sheet dropped from the pair of sheet holders after a leading edge of the sheet is aligned by the leading-edge aligner. The control circuitry controls operations of the leading-edge aligner and the pair of sheet holders.

A pair of regulating guides can guide both end edges in a sheet width direction Y of a sheet being conveyed being nipped by a conveying belt and balls. The pair of regulating guides can move to their respective guide positions each for guiding one of both end edges of the sheet and their respective retracting positions each retracting from one of the both end edges of the sheet by a distance larger than the guide position. A guide moving unit for moving the pair of regulating guides makes each of the pair of regulating guides reach the guide position from the retracting position after the rear end of the sheet passed from a conveying roller pair positioned on the upstream side to the conveying belt passes the conveying roller pair.

To provide a configuration for allowing a user to easily take out a sheet stopped on a conveying belt. Regulating guides are disposed on both sides of a conveying belt in a sheet width direction Y and can guide both end edges in the sheet width direction of a sheet S being conveyed while being nipped by the conveying belt and the balls. A take-out port is provided on a side close to the regulating guide in the sheet width direction and serves as an opening for taking out the sheet stopped on the conveying belt. The regulating guide on a side away from the take-out port moves in the sheet width direction Y toward the take-out port when the sheet is stopped on the conveying belt.

A sheet aligning device includes a support member, a regulation member, a regulation member moving mechanism, and an alignment member. The support member supports leading ends of sheets. The regulation member is connected to the support member and is provided to face an inclined tray in such a way as to define a sheet entry space in which the leading ends of the sheets enter. The regulation member moving mechanism is configured to, each time a sheet is conveyed onto the inclined tray, move the regulation member in a separating direction to widen the sheet entry space, and then in an approaching direction to narrow the sheet entry space. The alignment member aligns the sheets by abutting on rear ends of the sheets.

An example stacking system comprises a stacking member movable between a first position in which the stacking member is configured to partially support a first stack of printed substrates, and a second position in which the stacking member is disengaged from the first stack. A receptacle positioned below the stacking member is configured to hold a second stack of printed substrates. A controller is configured to cause the stacking member to move between the first position and the second position when the first stack satisfies a criterion, thereby depositing the first stack into the receptacle on top of the second stack.

A device for offsetting sheets as they are conveyed in a paper path toward a stacker includes a narrow channel mounted to a set of linked arms which when moved in a process direction (upstream-downstream) articulate in a cross process direction (inboard-outboard) to register the sheets at various locations for stacking or finish processing. The linked arms keep the channel parallel to the paper path at all times regardless of inboard-outboard offset.