An image forming system includes an image forming unit configured to form an image on a sheet and provided in an apparatus body, a first sheet processing device provided in a first housing and configured to perform a first binding processing, without using a needle, on the sheet that is formed with the image and stacked, and a second sheet processing device provided in a second housing that is different from the first housing and configured to perform a second binding processing, using a needle, on the sheet that is formed with the image and stacked. The first housing and the second housing are mounted on the apparatus body. At least a portion of the first housing is positioned within a range exclusively occupied by a rectangular space defined by a maximum outer dimension of the apparatus body. The second housing is positioned outside the rectangular space.

A staple-less binding unit is provided with upper and lower die portions having pluralities of concave and convex teeth engaging with each other. A control portion causes the staple-less binding unit to carry out a binding process of binding a sheet bundle by biting the sheet bundle by the upper and lower die portions and to carry out a cleaning process of engaging the upper and lower die portions in a non-binding process in which no binding process is carried out.

An image processing apparatus performs a binding process for binding a plurality of sheets. When a binding unit configured to bind sheets without using a staple performs the binding process, the image processing apparatus adds a mark for identifying a position where the binding process is performed.

A sheet processing apparatus includes a binding unit including a first portion and a second portion and configured to nip a sheet bundle between the first portion and the second portion to deform the sheet bundle in a thickness direction to bind the sheet bundle, and a detachment unit configured to push the bound sheet bundle toward the second portion to detach the bound sheet bundle from the first portion.

A printing control apparatus configured to control a binding unit configured to perform a binding processing for binding sheets without using a staple includes a control unit that controls the biding unit to divide sheets subjected to printing into sheet groups in units of a number of sheets bindable by the binding unit, and to apply the binding processing to each of sheet groups or controls another binding unit to bind the sheets subjected to printing using a staple.

A recording material processing apparatus includes: first teeth that are used for binding processing of a recording material bundle; second teeth configured to move toward the first teeth and to press the recording material bundle positioned between the first teeth and the second teeth; a first metal block configured to support the first teeth; and a second metal block configured to support the second teeth.

A recording medium processing apparatus includes: first teeth to be used in a process of binding a recording medium bundle; second teeth to be moved toward the first teeth to press the recording medium bundle positioned between the first teeth and the second teeth; and a moving unit that includes a screw moving unit that moves the second teeth with respect to the first teeth by rotating a screw in a circumferential direction, the screw being meshed with an interlocking portion interlocked with the second teeth. A moving speed of the second teeth being moved by the moving unit is varied.

A recording material processing apparatus includes: first teeth that are used for binding processing of a recording material bundle; second teeth configured to move toward the first teeth and to press the recording material bundle positioned between the first teeth and the second teeth; a first metal block configured to support the first teeth; and a second metal block configured to support 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; 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 sheet post-processing apparatus includes a first stapler and a second stapler having different thicknesses of sheets on which a binding process can be performed. A control unit can perform a manual staple mode. If the first stapler is selected as a stapler for performing the binding process in the manual staple mode, the control unit controls the alignment member moving mechanism to move alignment members to a position defining a first insertion position for guiding the sheets to a first placing position. If the second stapler is selected, the control unit controls the alignment member moving mechanism to move the alignment members to a position defining a second insertion position for guiding the sheets to a second placing position.