A medium-transporting device includes: a medium-mounting section on which a medium is mounted; a feeding unit that includes a feeding roller and that is configured to be displaced between a contact posture and a separation posture; a first restricting member that is provided downstream of the feeding roller in the transport direction and that is configured to switch between a restriction posture in which the first restricting member restricts movement of the medium and a retreat posture in which the first restricting member permits the movement of the medium; a first motor configured to generate power for rotating the feeding roller; and a second motor configured to generate power for switching a posture of the first restricting member, in which an operation of rotating the feeding roller and an operation of switching the first restricting member from the restriction posture to the retreat posture are performed in parallel.

An image forming system includes an image forming apparatus, a first conveyance path, a sheet feeding unit, a sheet post-processing unit, and a controller. The image forming apparatus has a first feed portion, and an image forming portion. The sheet feeding apparatus has a sheet stacking portion, a second feed portion, a relay conveyance portion, and a remaining amount detecting portion. When, during continuous printing, the existing number of recording sheets present in a conveyance passage from a confluence portion to the first feed portion is more than the constituting number of recording sheets contained in one bundle of sheets and in addition the sensing result of the remaining amount sensor is equal to or less than a predetermined amount, the controller controls first feed portion such that the existing number of the recording sheets is less than the constituting number of recording sheets.

A vacuum belt conveyor sequentially delivers sheet articles to a digital printer. The sheets are held in position by vacuum on the underside of the sheets through apertures in the belts and covered by the sheets. A plurality of independent plenums on the underside of the belt have chambers respectively communicating with rows of apertures extending along the belt. Vacuum is selectively applied from a manifold only to the plenum chambers that supply apertures that are covered by the sheets so that the ink from the printer will not be directed from its intended position on the sheet by vacuum from adjacent uncovered belt apertures. The sheets are fed to the conveyor in synchronism with the conveyor speed by a timed feeder so that the sheets are carried by the conveyor with a predetermined gap between the sheets and no belt apertures in the gap. A sensor counts the apertures in the belt and activates the feeder at predetermined time intervals.

A vacuum belt conveyor sequentially delivers sheet articles to a digital printer. The sheets are held in position by vacuum on the underside of the sheets through apertures in the belts and covered by the sheets. A plurality of independent plenums on the underside of the belt have chambers respectively communicating with rows of apertures extending along the belt. Vacuum is selectively applied from a manifold only to the plenum chambers that supply apertures that are covered by the sheets so that the ink from the printer will not be directed from its intended position on the sheet by vacuum from adjacent uncovered belt apertures. The sheets are fed to the conveyor in synchronism with the conveyor speed by a timed feeder so that the sheets are carried by the conveyor with a predetermined gap between the sheets and no belt apertures in the gap. A sensor counts the apertures in the belt and activates the feeder at predetermined time intervals.

An image forming apparatus is configured to execute a print job for printing on a sheet supplied from a sheet supplying mechanism formed of a first sheet feeding apparatus configured to temporarily stop conveyance of the sheet within a conveyance path thereof or a second sheet feeding apparatus configured not to temporarily stop conveyance of the sheet within a conveyance path thereof. The image forming apparatus includes an image former configured to form an image on the sheet; an obtaining device configured to obtain apparatus information representing a type of an apparatus forming the sheet supplying mechanism; and a controller configured to determine, based on the apparatus information and the sheet supplying mechanism instructed to feed the sheet by the print job, timings to send, to the sheet supplying mechanism, a feed request for starting to feed the sheet and a delivery request for instructing to deliver the sheet.

An image forming apparatus is configured to execute a print job for printing on a sheet supplied from a sheet supplying mechanism formed of a first sheet feeding apparatus configured to temporarily stop conveyance of the sheet within a conveyance path thereof or a second sheet feeding apparatus configured not to temporarily stop conveyance of the sheet within a conveyance path thereof. The image forming apparatus includes an image former configured to form an image on the sheet; an obtaining device configured to obtain apparatus information representing a type of an apparatus forming the sheet supplying mechanism; and a controller configured to determine, based on the apparatus information and the sheet supplying mechanism instructed to feed the sheet by the print job, timings to send, to the sheet supplying mechanism, a feed request for starting to feed the sheet and a delivery request for instructing to deliver the sheet.

A sheet processing device includes a post-processing unit, a process tray, a first sensor, a second sensor, and a control unit. The post-processing unit performs post-processing on the sheet. The process tray places the sheet to be post-processed on the upper surface. The first sensor is disposed on the upper side of the process tray. The first sensor outputs a first signal corresponding to a first distance to an object which is disposed at a first position of the process tray. The second sensor is disposed on the upper side of the process tray. The second sensor outputs a second signal corresponding to a second distance to the object which is disposed at a second position on the downstream side in a sheet discharge direction from the first position of the process tray. The control unit controls the post-processing using the first signal and the second signal.

A sheet processing device includes a post-processing unit, a process tray, a first sensor, a second sensor, and a control unit. The post-processing unit performs post-processing on the sheet. The process tray places the sheet to be post-processed on the upper surface. The first sensor is disposed on the upper side of the process tray. The first sensor outputs a first signal corresponding to a first distance to an object which is disposed at a first position of the process tray. The second sensor is disposed on the upper side of the process tray. The second sensor outputs a second signal corresponding to a second distance to the object which is disposed at a second position on the downstream side in a sheet discharge direction from the first position of the process tray. The control unit controls the post-processing using the first signal and the second signal.

A medium conveying apparatus includes a first optical sensor located on an upper part of the housing and in a central part of the housing in a direction perpendicular to a medium conveying direction, a second optical sensor located on an upper part of the housing and on a side of the first optical sensor in the direction perpendicular to the medium conveying direction, and a processor to detect a folding of a medium based on the first signal or the second signal, and stop feeding of the medium by the feed roller in accordance with a detection result of the folding of the medium. The first light emitter emits first light toward a downstream side of the medium in the medium conveying direction, and the second light emitter emits second light toward an upstream side of the medium in the medium conveying direction.

A medium conveying apparatus includes a first optical sensor located on an upper part of the housing and in a central part of the housing in a direction perpendicular to a medium conveying direction, a second optical sensor located on an upper part of the housing and on a side of the first optical sensor in the direction perpendicular to the medium conveying direction, and a processor to detect a folding of a medium based on the first signal or the second signal, and stop feeding of the medium by the feed roller in accordance with a detection result of the folding of the medium. The first light emitter emits first light toward a downstream side of the medium in the medium conveying direction, and the second light emitter emits second light toward an upstream side of the medium in the medium conveying direction.