To provide a sheet stacking apparatus and image forming system capable of improving alignment characteristics also in the case where an aligning section is not able to act on a sheet discharged onto a stacking tray, the sheet stacking apparatus and image forming system include a stacking tray stacking discharged sheets, a pair of aligning sections capable of shifting in a width direction to align the width direction crossing a direction in which the sheet to stack on the stacking tray is discharged, and a control section that controls a relative position of the aligning sections and the sheet to discharge so that one of the pair of the aligning sections regulates a shift of the sheet stacked on the stacking tray to one direction side in the width direction, when a sheet with a predetermined width in the width direction of the sheet is discharged to the stacking tray.

To provide a sheet stacking apparatus and image forming system capable of improving alignment characteristics also in the case where an aligning section is not able to act on a sheet discharged onto a stacking tray, the sheet stacking apparatus and image forming system include a stacking tray stacking discharged sheets, a pair of aligning sections capable of shifting in a width direction to align the width direction crossing a direction in which the sheet to stack on the stacking tray is discharged, and a control section that controls a relative position of the aligning sections and the sheet to discharge so that one of the pair of the aligning sections regulates a shift of the sheet stacked on the stacking tray to one direction side in the width direction, when a sheet with a predetermined width in the width direction of the sheet is discharged to the stacking tray.

An image forming apparatus includes an image former that forms an image on a sheet of paper, a detector that detects a physical property of a sheet of paper, a receiver that receives paper identification information used in identification of a sheet of paper designated by a user, and a hardware processor. The hardware processor performs: first judgement of judging whether or not there is a correspondence between the paper identification information received by the receiver and a detection result by the detector, second judgement of judging whether or not there is a correspondence between a detection result by the detector of a first sheet of paper conveyed and a detection result by the detector of a second sheet of paper conveyed; and operation control of the image former based on a first judgement result in the first judgement and a second judgement result in the second judgement.

An image forming apparatus includes an image former that forms an image on a sheet of paper, a detector that detects a physical property of a sheet of paper, a receiver that receives paper identification information used in identification of a sheet of paper designated by a user, and a hardware processor. The hardware processor performs: first judgement of judging whether or not there is a correspondence between the paper identification information received by the receiver and a detection result by the detector, second judgement of judging whether or not there is a correspondence between a detection result by the detector of a first sheet of paper conveyed and a detection result by the detector of a second sheet of paper conveyed; and operation control of the image former based on a first judgement result in the first judgement and a second judgement result in the second judgement.

A sheet sorting device includes a plurality of trays, a tray shifter, a tray stop position detector, and circuitry. The plurality of trays is disposed in multiple stages in a vertical direction and configured to stack a sheet. The tray shifter is configured to move the plurality of trays separately in a tray shift direction. The tray stop position detector is configured to detect stop positions of the plurality of trays separately. The circuitry is configured to cause the tray shifter to move the plurality of trays to home positions in an initial operation, at least one tray having a home position opposite to a home position of another tray in the tray shift direction. The circuitry is configured to, while moving the plurality of trays at a same time in the initial operation, cause the tray shifter to move the trays in directions opposite to each other.

A post-processing device includes a transport path along which a medium printed with liquid ejected by a liquid ejecting portion is transported, an intermediate tray on which the medium is stacked, a first transporting member starting a first transporting operation of transporting the medium upstream in a transport direction after a rear end of the medium passes through the transport path, a rear-end alignment portion that comes into contact with the rear end of the medium transported by the first transporting member and that aligns the medium, a control portion controlling an operation of the first transporting member, and a detection portion detecting a transporting state of the medium in the intermediate tray, in which when the control portion determines, from an output of the detection portion, that the medium reaches the rear-end alignment portion, the control portion regulates the first transporting operation of the first transporting member.

A postprocessing apparatus includes a horizontal alignment plate, a binder, a tray, and a shift actuator assembly. The horizontal alignment plate is positioned to align sheets in a sheet width direction. The binder binds sheets to form bound sheet bundles. The bound sheet bundles are stacked on the tray. The shift actuator assembly shifts the bound sheet bundles in the sheet width direction. A postprocessing controller controls the shift actuator assembly to shift the bound sheet bundles such that swollen portions of the bound sheet bundles are shifted inward of the horizontal alignment plate in the sheet width direction when the processed sheets are piled on the tray to the vicinity of the horizontal alignment plate.

A postprocessing apparatus includes a horizontal alignment plate, a binder, a tray, and a shift actuator assembly. The horizontal alignment plate is positioned to align sheets in a sheet width direction. The binder binds sheets to form bound sheet bundles. The bound sheet bundles are stacked on the tray. The shift actuator assembly shifts the bound sheet bundles in the sheet width direction. A postprocessing controller controls the shift actuator assembly to shift the bound sheet bundles such that swollen portions of the bound sheet bundles are shifted inward of the horizontal alignment plate in the sheet width direction when the processed sheets are piled on the tray to the vicinity of the horizontal alignment plate.

A medium processing apparatus includes a liquid applier, a crimper, a stapler, and circuitry. The liquid applier applies liquid to a liquid application position of a medium. The crimper presses and deforms at least a part to which the liquid is applied by the liquid applier, to bind a plurality of media including the medium to which the liquid is applied. The stapler performs stapling with a staple on a medium bundle in which the plurality of media is bound by the crimper. The circuitry controls operations of the crimper, the liquid applier, and the stapler, and selectively switches between first binding performed by the liquid applier and the crimper and second binding performed by only the stapler, in accordance with information on the medium or a binding position at which the medium bundle is bound by the crimper.

A medium processing apparatus includes a liquid applier, a crimper, a stapler, and circuitry. The liquid applier applies liquid to a liquid application position of a medium. The crimper presses and deforms at least a part to which the liquid is applied by the liquid applier, to bind a plurality of media including the medium to which the liquid is applied. The stapler performs stapling with a staple on a medium bundle in which the plurality of media is bound by the crimper. The circuitry controls operations of the crimper, the liquid applier, and the stapler, and selectively switches between first binding performed by the liquid applier and the crimper and second binding performed by only the stapler, in accordance with information on the medium or a binding position at which the medium bundle is bound by the crimper.