A sheet processing apparatus, including: a rotary member pair configured to nip a sheet conveyed in a conveyance path and rotate to fold the sheet; and a guide portion provided between one rotary member of the rotary member pair and the conveyance path, the one rotary member including: a first part; and a second part, wherein a first distance between the first part and a rotary shaft center of the one rotary member is greater than a second distance between the second part and the rotary shaft center, and wherein the guide portion is positioned at a first position in case that the second part is positioned at a first rotational position, and the guide portion is positioned at a second position different from the first position in a distance from the rotary shaft center in case that the second part is positioned at a second rotational position.

A sheet processing apparatus includes a tray, a first binder, a second binder, a feeder, and circuitry. The tray receives and stores a sheet bundle. The first binder presses the sheet bundle to bind the sheet bundle. The second binder penetrates the sheet bundle with a needle to bind the sheet bundle. The feeder feeds the sheet bundle in a first direction, and moves the sheet bundle in a second direction. The circuitry causes the feeder to move the sheet bundle on the tray in the second direction, moves the first binder from a binding position to a home position different from the binding position, and moves the second binder to the binding position in the width direction to bind the sheet bundle by the second binder after the sheet bundle is moved in the second direction and the first binder is moved to the home position.

The present invention is to provide a sheet bundle binding device having both a staple binding unit and a staple-free binding unit, capable of performing binding in two stages of proper binding and temporary binding so as to obtain a desired binding force and to easily remove some sheets from a bound sheet bundle. A binding control section determines, based on user's settings, whether or not to perform first binding in which a first sheet bundle Sb1 is subjected to the proper binding using the staple binding unit or staple-free binding unit and determines whether or not to perform second binding in which a second sheet bundle obtained by accumulating additional sheets on the first sheet bundle is subjected to the temporary binding using the staple-free binding unit so as to control binding forces with which the first and second sheet bundles are bound.

A sheet-stapling apparatus mounts a center-folded booklet and staples the booklet at a fold of the booklet by a staple. The sheet-stapling apparatus has a supporting member that mounts the center-folded booklet, a pushing member that pushes the booklet to the supporting member, a stapler that penetrates the staple through the booklet and a clincher that clinches legs of the staple to bind the booklet. The pushing member has a groove that pushes the fold of the booklet and maintains the fold of the booklet at a pushing angle. The supporting member forms the space between the clincher and the booklet.

A medium processing apparatus includes a liquid applier, a crimper, and a mover. The liquid applier applies liquid on a medium. The crimper crimps and binds multiple media including the medium with the liquid applied. The mover moves the liquid applier. The liquid applier includes a liquid storage, a liquid supply member, a liquid application member, and a liquid supply facilitator. The liquid supply member has first and second ends. The liquid application member is attached to the second end of the liquid supply member. The liquid application member contacts the medium to apply the liquid onto the medium. The liquid supply facilitator increases a contact area between the liquid supply member and the liquid in the liquid storage, in response to a movement of the liquid applier. The mover moves the liquid applier between an application position and a separation position.

A thickness detection device for detecting a thickness of an object includes a thickness-direction moving member and a thickness detector. The thickness-direction moving member is held to be movable in a direction of the thickness by the object inserted into a cavity having an opening that opens in a plurality of directions. The thickness detector detects the thickness-direction moving member moved by the object inserted into the cavity to detect the thickness of the object. The thickness-direction moving member has a portion to face the object inserted into the cavity. The portion has a shape inclined relative to an insertion direction of the object.

A medium processing apparatus includes a liquid applier, a crimper, and a mover. The liquid applier applies liquid on a medium. The crimper crimps and binds multiple media including the medium with the liquid applied. The mover moves the liquid applier. The liquid applier includes a liquid storage, a liquid supply member, a liquid application member, and a liquid supply facilitator. The liquid supply member has first and second ends. The liquid application member is attached to the second end of the liquid supply member. The liquid application member contacts the medium to apply the liquid onto the medium. The liquid supply facilitator increases a contact area between the liquid supply member and the liquid in the liquid storage, in response to a movement of the liquid applier. The mover moves the liquid applier between an application position and a separation position.

A thickness detection device for detecting a thickness of an object includes a thickness-direction moving member and a thickness detector. The thickness-direction moving member is held to be movable in a direction of the thickness by the object inserted into a cavity having an opening that opens in a plurality of directions. The thickness detector detects the thickness-direction moving member moved by the object inserted into the cavity to detect the thickness of the object. The thickness-direction moving member has a portion to face the object inserted into the cavity. The portion has a shape inclined relative to an insertion direction of the object.