There are a paper storage that stores paper on which an image is formed, a paper guide that is movably provided in the paper storage and restricts a position of the stored paper, a paper size acquirer that acquires a size of the paper stored in the paper storage, a size change determiner that determines, by using the acquired size of the paper, whether the paper stored in the paper storage was changed, a confirmation information selector that, when it is determined that the paper stored in the paper storage was changed, selects confirmation information requesting confirmation of a position of the paper guide in the paper storage in accordance with a difference in size between paper before and after the change, and a confirmation information notifier that notifies the selected confirmation information.

A paper size detection device comprises a first actuator comprising a plurality of operating arms and a first detection arm to move in association with movement of the plurality of operating arms, the plurality of operating arms having lengths or angles different from each other; a first sensor to output different results in accordance with a position of the first detection arm; a second actuator comprising one operating arm and a second detection arm to move in association with movement of the one operating arm; and a second sensor to output different results in accordance with a position of the second detection arm.

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 belt 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.

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 belt 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.

A medium-discharging device includes: a medium-discharging section that discharges a medium; a medium-receiving tray that receives the medium discharged by the medium-discharging section; a light-emitting section that emits light to the medium-receiving tray; and a control section that controls the light-emitting section, in which the medium-receiving tray is configured to switch between a first state in which the medium-receiving tray is stored in an apparatus main body that includes the medium-discharging section and a second state in which the medium-receiving tray protrudes from the apparatus main body, and the control section controls the light-emitting section in accordance with a state or operation of the medium-receiving tray.

A medium-discharging device includes: a medium-discharging section that discharges a medium; a medium-receiving tray that receives the medium discharged by the medium-discharging section; a light-emitting section that emits light to the medium-receiving tray; and a control section that controls the light-emitting section, in which the medium-receiving tray is configured to switch between a first state in which the medium-receiving tray is stored in an apparatus main body that includes the medium-discharging section and a second state in which the medium-receiving tray protrudes from the apparatus main body, and the control section controls the light-emitting section in accordance with a state or operation of the medium-receiving tray.

A sheet suction device includes a drum having multiple suction ports in a circumferential surface of the drum, the drum configured to bear a sheet on the circumferential surface and rotate in a circumferential direction of the drum, and a suction device configured to suck the sheet through the multiple suction ports to attract the sheet on the circumferential surface. The drum includes multiple suction regions aligned in the circumferential direction on the circumferential surface, each of the multiple suction regions includes the multiple suction ports aligned in the circumferential direction and in an axial direction of the drum on the circumferential surface, the multiple suction regions include an upstream region, a middle region, and a downstream region in the circumferential direction, and the middle region has the multiple suction ports at both outer sides in the axial direction of the drum.

A sheet stacking device includes a sheet stacker, an image capturing device, and circuitry. The sheet stacker stacks a sheet. The image capturing device captures an image of a whole face of the sheet stacked in the sheet stacker. The circuitry detects a size of the sheet stacked in the sheet stacker, whether the sheet stacked in the sheet stacker is a last sheet, or whether an image is formed on an image forming face of the sheet, based on image data of the image captured by the image capturing device.

A control unit is capable of selectively executing a first mode and a second mode, the first mode being a mode in which a plurality of sheets having different sizes including a non-standard size are fed by the feeding unit, and the second mode being a mode in which a plurality of sheets having different sizes including only standard sizes are fed by the feeding unit. If the detection unit detects a sheet in a state where the supporting portion is located at the second position and the first mode is selected, the control unit waits for an instruction to start sheet feeding without causing the lifting unit to lift the supporting portion to the first position, and causes the lifting unit to lift the supporting portion to the first position in response to the instruction to start sheet feeding.

A medium conveying apparatus includes a main body, a paper ejection tray main body that is supported by the main body and that is arranged at a paper ejection tray unfolding position or a paper ejection tray storage position, an extension member that is supported by the paper ejection tray main body and that is arranged at an expansion position or a contraction position, a cover that is supported by the main body and that is arranged at an opening position or a closing position, and a contact member that is fixed to the cover, wherein the cover is arranged at a midway position between the opening position and the closing position when the paper ejection tray main body is arranged at the paper ejection tray storage position and when the extension member is not arranged at the contraction position and is in contact with the contact member.