A recording medium processing apparatus includes first teeth that are used for binding processing of a recording medium bundle; second teeth that move toward the first teeth and press the recording medium bundle located between the first teeth and the second teeth; and a control unit that moves the second teeth toward the first teeth to press the second teeth against the first teeth in a state in which there is no recording medium bundle between the first teeth and the second teeth.

A recording medium processing apparatus includes first teeth that are used for binding processing of a recording medium bundle; second teeth that move toward the first teeth and press the recording medium bundle located between the first teeth and the second teeth; a position detection unit that detects a position of the second teeth; and a control unit that controls movement of the second teeth on the basis of the position detected by the position detection unit.

A recording medium processing apparatus includes first teeth that are used for binding processing of a recording medium bundle; second teeth that move toward the first teeth and press the recording medium bundle located between the first teeth and the second teeth; a position detection unit that detects a position of the second teeth; and a control unit that controls movement of the second teeth on the basis of the position detected by the position detection unit.

A binding device includes: an upper teeth portion having at least one teeth row that forms unevenness in a recording material bundle; a lower teeth portion having at least one teeth row that forms unevenness in the recording material bundle and being paired with the upper teeth portion; and at least one holding portion that holds the recording material bundle at a position different from a position where the upper teeth portion and the lower teeth portion have a binding function, when binding processing is performed by the upper teeth portion and the lower teeth portion.

A binding device includes: an upper teeth portion having at least one teeth row that forms unevenness in a recording material bundle; a lower teeth portion having at least one teeth row that forms unevenness in the recording material bundle and being paired with the upper teeth portion; and at least one holding portion that holds the recording material bundle at a position different from a position where the upper teeth portion and the lower teeth portion have a binding function, when binding processing is performed by the upper teeth portion and the lower teeth portion.

An example sheet guide devices comprises a housing and a guide member coupled to the housing. The housing is to receive a stack of sheets to staple. The guide member includes a cylinder shaft, a counterbalance component, and guide arm. The cylinder shaft is rotatable and disposed within the housing. The counterbalance component is disposed with the cylinder shaft to shift a center of gravity of the guide member in a first direction. The guide arm is disposed off-center from a central axis of the cylinder shaft in a second direction.

An example sheet guide devices comprises a housing and a guide member coupled to the housing. The housing is to receive a stack of sheets to staple. The guide member includes a cylinder shaft, a counterbalance component, and guide arm. The cylinder shaft is rotatable and disposed within the housing. The counterbalance component is disposed with the cylinder shaft to shift a center of gravity of the guide member in a first direction. The guide arm is disposed off-center from a central axis of the cylinder shaft in a second direction.

An image forming apparatus is to supply paper sheets on which images are formed to a post-processing apparatus to pressure-bind binding areas of paper sheets bundled. The image forming apparatus includes a conveyor, an image forming device, and a controller. The conveyor conveys a paper sheet. The image forming device discharges liquid ink to the paper sheet conveyed by the conveyor. The controller repeatedly executes a process of: causing the conveyor to convey the paper sheet to a position facing the image forming device; causing the image forming device to discharge the liquid ink to form an image on the paper sheet; and causing the conveyor to convey the paper sheet on which the image has been formed toward the post-processing apparatus. The controller further causes the image forming device to apply the liquid ink to a binding area of at least one of the paper sheets.

A sheet conveyance apparatus includes a controller controlling a driver to cause a guide to start rotation in a state in which a trailing end in a sheet conveyance direction of a preceding sheet conveyed by a roller pair having a first roller and a second roller such that the trailing end of the preceding sheet is moved from the position above a first guide to a position between a second guide and a sheet support by the rotation of the guide and that a succeeding sheet conveyed by the roller pair subsequently to the preceding sheet passes the position above the first guide after the rotation of the guide. The first roller is rotated by a driving force supplied from a driving source, and the guide rotates about a rotation axis of the first roller while rotating relatively to the first roller.

A sheet conveyance apparatus includes a controller controlling a driver to cause a guide to start rotation in a state in which a trailing end in a sheet conveyance direction of a preceding sheet conveyed by a roller pair having a first roller and a second roller such that the trailing end of the preceding sheet is moved from the position above a first guide to a position between a second guide and a sheet support by the rotation of the guide and that a succeeding sheet conveyed by the roller pair subsequently to the preceding sheet passes the position above the first guide after the rotation of the guide. The first roller is rotated by a driving force supplied from a driving source, and the guide rotates about a rotation axis of the first roller while rotating relatively to the first roller.