An inkjet printer includes: at least one inkjet head configured to eject ink to a sheet and print an image; at least one stiffening conveyor configured to convey the sheet toward the at least one inkjet head in a conveyance direction while stiffening the sheet by deforming the sheet into a wave shape in a width direction orthogonal to the conveyance direction; and at least one platen arranged to face the at least one inkjet head and having a protrusion, the protrusion provided on a surface of the at least one platen facing the at least one inkjet head and configured to support a convex portion in the wave shape of the deformed sheet, the at least one platen configured to support the sheet while keeping the sheet deformed in the wave shape.

A sheet pressing mechanism includes a pressing member configured to press a sheet that has been deformed to corrugate in a width direction that is orthogonal to a sheet discharging direction when the sheet is discharged toward a discharge tray. The pressing member has a first pressing area for pressing portions other than a top portion of a crest of the sheet when the discharged sheet comes into contact with the pressing member.

An image forming apparatus includes an image forming unit to form an image on a sheet, a sheet ejection section to which a relay unit and a sheet processing apparatus are removably coupled, a driving-side ejection roller disposed in the sheet ejection section, to eject the sheet outside the apparatus, a plurality of driven-side ejection rollers that are replaceable, one of which is disposed facing the driving-side ejection roller, and a roller holder removably secured to the sheet ejection section to hold the one of the plurality of driven-side ejection rollers. Each driven-side ejection roller has a shaft and a plurality of roller bodies attached to the shaft and lined in an axial direction of the shaft. The driven-side ejection roller is replaced with another driven-side ejection roller in accordance with whether or not the relay unit and the sheet processing apparatus are coupled to the sheet ejection section.

A sheet discharge device has a sheet discharge port, a conveying guide, discharge roller pairs, corrugation members, and first biasing members, and discharges sheets onto a discharge tray sequentially. The corrugation members are arranged between the discharge roller pairs to protrude beyond a nip portion in them and stiffens the sheet by pressing one side of the sheet. The first biasing members bias the corrugation members in the protruding direction. Each of the corrugation members has, in a region extending from the upstream side to a downstream-side end part of the discharge roller pairs in the sheet discharge direction and including the nip portion, a first pressing part making contact with one side of the sheet and, in a region further on the downstream side of the downstream-side end part of the discharge roller pairs, a second pressing part making contact with one side of the sheet.

An image recording apparatus for recording an image on a sheet includes a recording section which records the image on the sheet in a transport passage for transporting the sheet in a transport direction and multiple plates which are spaced apart from each other in a widthwise direction. These multiple plates include a first type of plate and a second type of plate. Plates of a first type of plate are configured to overlap a sheet when viewed in a direction perpendicular to the transport direction and the widthwise direction, while plates of the second type of plate do not.

In one example, a device for partially dried inkjet media output management includes a starwheel positioned on a first side between a number of rollers positioned on a second side to corrugate partially dried inkjet media between the starwheel and the number of rollers.

A sheet discharging device includes a stacking portion configured to stack a sheet; a discharging portion configured to feed the sheet so as to be discharged to the stacking portion, wherein the discharging portion includes a first roller configured to feed the sheet and a second roller provided so as to be contactable to a sheet surface opposite from another sheet surface to which the first roller is contactable to; and an electrically discharging member configured to electrically discharge the sheet in contact with the sheet fed by the discharging portion. As viewed in a widthwise direction perpendicular to a discharging direction of the sheet, the electrically discharging member is provided so as to extend through between rotational axes of the first and second rollers in the discharging direction of the sheet.

A post-processing device is provided with a post-processing unit which performs post-processing of a recording medium on which recording is performed, a transport path through which the recording medium is transported, or a deformation suppressing unit which suppresses deformation of the recording medium on a mounting unit on which the recording medium is mounted, in which the deformation suppressing unit is controlled based on a predetermined parameter related to recording processing with respect to the recording medium.

A sheet discharge device includes: a conveying portion which conveys the sheet in a conveying direction with the sheet interposed between a first roller and a second roller; a first conveying guide; a second conveying guide; a rotating portion which is disposed on a shaft of the first roller and has an outer diameter larger than that of the first roller; and a guide portion which is provided in the first conveying guide and in which an interval between the guide portion and the opposite second conveying guide becomes narrower toward a downstream side in the conveying direction, the guide portion being located at a position corresponding to the rotating portion in a sheet width direction orthogonal to the conveying direction.

There is provided a sheet processing apparatus including a conveyance unit configured to convey a sheet, a creasing unit configured to form a first crease and a second crease different from the first crease on the sheet, and a detection unit configured to detect a direction of the first crease. When a second crease is to be formed after the formation of the first crease by the creasing unit, a direction of the second crease with respect to a widthwise direction of the sheet is controlled based on a detection result of the detection unit.