A binding device includes a first pressing member that presses a recording-medium stack from one surface side of the recording-medium stack, a second pressing member disposed at a position opposed to the first pressing member to press the recording-medium stack from the other surface side of the recording-medium stack, and a reduction part provided in at least one pressing member of the first pressing member and the second pressing member to reduce creases in recording media of the recording-medium stack in a binding operation when a number of the recording media in the recording-medium stack is smaller than a maximum number of recording media to be bound by the first pressing member and the second pressing member.

A binding apparatus includes a first pressing member including a base part and multiple projections projecting from the base part, the first pressing member presses a recording media stack from one side; and a second pressing member including a base part and multiple projections projecting from the base part, the second pressing member facing the first pressing member and pressing the recording media stack from the other side. At least one of the first and second pressing members has at least one lower projection whose apex in a projecting direction closer to the base part than the apexes of the other projections are, and the lower projection is provided in the first or second pressing member that has more projections than the other, or more lower projections are provided in the first or second pressing member that has more projections than the other.

A medium processing apparatus includes a liquid applier, a post-processing device, and a controller that is circuitry. The liquid applier applies liquid on at least one medium. The post-processing device performs a combination of various types of post-processes including a liquid application crimp binding and a crimp binding and a various types of bindings including a dual binding, a parallel binding, and an oblique binding, on a bundle of media including the at least one medium for a number of times. The circuitry is to change the number of times of the post-process according to the combination of the various types of the post processes and the various types of bindings, to be performed.

A printing system includes a printing apparatus that prints an image on a sheet, a sheet processer that executes sheet processing, and a sheet detection sensor that detects a sheet on which the sheet processing is performed not in association with the printing of an image, where the printing of an image is restricted in response to detection of a sheet by the sheet detection sensor.

A medium processing apparatus includes a liquid applier and a post-processing device. The liquid applier includes a liquid application member including a foam containable a liquid to apply the liquid to a liquid application region in a part of at least one medium of a bundle of media. The post-processing device performs a given process on a post-processing region in the part of at least one medium having the liquid application region on which the liquid is applied by the liquid applier. The liquid applier applies the liquid to the liquid application region overlapped with at least a part of the post-processing region.

A sheet processing device includes: an accumulator on which sheets are accumulated; a staple driver; a staple receiver disposed at a position facing the staple driver, wherein the staple driver drives a staple into the sheets when the sheet are between the staple receiver and the staple driver; an arm that extends from the staple driver in a direction perpendicular to a staple driving direction to operate the staple driver in the staple driving direction; and a regulator that regulates deviation produced when the staple driver drives the staple. The deviation is in a short length direction of the arm perpendicular to a long length direction of the arm and to the staple driving direction.

A stapler apparatus may be provided. More specifically, a stapler apparatus capable of automatically stapling a bundle of sheets output from an image forming apparatus such as a copy machine, a printer, a facsimile or the like may be provided. The stapler includes: a guide plate in which a slot having a branch structure has been formed; a moving frame which is reciprocatively movable on the guide plate; a rotation frame which is rotatable on the moving frame and includes a plurality of levers mounted thereon, the plurality of levers moving along the inside and outside of the slot or change paths; a path change member which changes a movement path of any one of the plurality of levers; and a stapler which is mounted on the rotation frame and is in conjunction with the rotation frame.

According to an embodiment, a sheet folding apparatus comprises a first roller, a second roller configured to be energized to the first roller, form a nip section together with the first roller, fold a sheet in half together with the first roller through the nip section and convey the sheet folded in half together with the first roller and a pressing force adjusting mechanism configured to be capable of increasing and decreasing a pressing force generated at the nip section. The pressing force adjusting mechanism causes a pressing force in a state of being conveying the sheet folded in half to be lower than that in a state of being folding the sheet in half.

A stapling apparatus capable of performing stapling on various positions by varying a moving path of a stapler is provided. The stapling apparatus includes a stapler, a driver configured to be coupled to the stapler and move the stapler, and a guide part configured to selectively switch a moving path of the stapler.

A bundle of printing media by eco-stapling often has a smaller thickness than a bundle of printing media by needle stapling by the thickness corresponding to an amount of used staples, although they have the same number of printing media, and there is room capable of stacking bundles in many cases in the eco-stapling. According to an embodiment, when a printing medium that has undergone an image forming process is taken in, stapling processing is performed on the printing medium, and then the printing medium is discharged to the tray, the following process is performed. That is, when the process is performed in accordance with instructed stapling processing, and the printing medium that has undergone the process is discharged outside the apparatus, the amount of printing media stacked on the tray is controlled in accordance with instructed stapling processing.