Abstract: In a sheet creaser, a sheet set is pushed between a pair of folding rollers to fold the sheet set. Then, a re-pressing roller re-presses the sheet set, which has been folded by the folding rollers, by rolling along the crease. Pressure applied on the sheet set by the folding rollers is released when the re-pressing roller re-presses the sheet set.

Abstract: A creasing device includes: a first member including a creasing blade; a first receiving member including an attachment surface where the first member is to be attached; a second member arranged to face the first member and including a first creasing channel and a second creasing channel opposite to the first creasing channel, the first creasing channel configured to allow the creasing blade to be fitted thereinto with the sheet between the first creasing channel and the creasing blade, the second creasing channel configured to allow the creasing blade to be fitted thereinto with the sheet between the second creasing channel and the creasing blade; a second receiving member including an attachment surface where the second member is to be attached; and a driving section that brings the first and second members into contact with each other and separates the first member and the second member from one another.

Abstract: A creasing apparatus that performs a creasing process on a sheet, the creasing apparatus including a first conveying path on which a creasing unit is located, the creasing unit performing a creasing process on a sheet conveyed therein; a second conveying path that conveys a sheet conveyed therein to a downstream side without any process being performed on the sheet; and a control unit that, while the first conveying path conveys a sheet so that the creasing unit performs the creasing process on the sheet, causes a subsequent sheet to be conveyed to the downstream side from the second conveying path.

Abstract: A sheet processing apparatus includes: a correcting unit that corrects alignment of a sheet; a post-processing unit that performs post-processing on the sheet after the correcting unit corrects the alignment of the sheet; and a creasing unit that forms a crease on the sheet after the correcting unit corrects the alignment of the sheet.

Abstract: A conveying device that conveys a sheet bundle with a flattened back-face portion includes a first conveying unit, a driving unit, and a second conveying unit. The first conveying unit retracts to a position where no driving force is exerted on the sheet bundle before a leading end of the sheet bundle formed in a flat spine shape enters, and abuts on the sheet bundle to exert conveying force after the leading end of the sheet bundle passes a conveying position. The driving unit moves the first conveying unit to retract to the position and to abut on the sheet bundle. The second conveying unit is positioned on an upstream side of the first conveying unit in a sheet bundle conveying direction and conveys the sheet bundle towards the first conveying unit.

Abstract: A creasing device that creases sheets on a per-sheet basis and includes: a first member extending perpendicularly to a sheet conveying direction and including a convex blade; a second member extending perpendicularly to the sheet conveying direction and including a concave blade, into which the convex blade is to be fitted; a drive unit that brings the first and the second members into and out of contact with each other, thereby producing a crease in a sheet interposed between the first and the second members; a sheet retainer driven by the drive unit and brought into contact with the second member with the sheet therebetween to retain the sheet across its full width; and a holding unit that holds the sheet retainer in a retaining state during creasing where the contact between the first and the second members starts at one point and develops in one direction.

Abstract: A creasing apparatus forming a crease on sheets one by one includes: a first member having a linear convex blade formed in a direction perpendicular to a sheet conveying direction; a second member having a concave blade being paired with the convex blade; and a drive unit that moves the first and second members so as to cause the convex blade and the concave blade to form a crease on a sheet stopped at a predetermined position. The first member forms the convex blade with first comb and second comb and the second member forms the concave blade with third comb and fourth comb that advance and retract relative to each other. The drive unit selects advanced and retracted positions of the first comb and second comb and advanced and retracted positions of the third comb and fourth comb so as to perform a creasing process or a perforating process.

Abstract: A creasing device, that forms a crease on a sheet, includes: a first member, extending in a direction perpendicular to a sheet conveying direction, on which a convex blade is formed; a second member on which a groove-like concave blade is formed such that the convex blade can be fitted into the concave blade by interposing the sheet therebetween; a drive unit that causes the first and the second members to interpose, therebetween, the sheet to form a crease on the sheet; a sheet-information acquiring unit that acquires first sheet information of the sheet to be creased; an adjusting unit that adjusts a pressing force exerted by the drive unit; and a control unit that sets the pressing force to an optimum pressing force for the sheet and that causes the drive unit to drive the first and the second members for creasing the sheet at the optimum pressing force.

Abstract: An image forming system includes: a folding unit that folds a sheet of paper to form a fold in the sheet; a creasing unit that, before the sheet is folded, produces a crease in the sheet at a fold position where the fold is to be formed; a crease-position adjusting unit that adjusts a crease position where the crease is to be produced; a fold-position adjusting unit that adjusts the fold position; a first input unit that receives an input specifying an amount, by which the crease position is to be adjusted; and a second input unit that receives an input specifying an amount, by which the fold position is to be adjusted, wherein when the fold position is adjusted by the second input unit, the crease position is also adjusted in synchronization with the adjustment of the fold position.

Abstract: A creasing device for creasing sheets on a per-sheet basis, the creasing device includes: a first member extending perpendicularly to a sheet conveying direction and including a male blade, which has a convex cross section; a second member extending perpendicularly to the sheet conveying direction and including a grooved female blade, into which the male blade to be fitted with a sheet between the female blade and the male blade; and a drive unit that brings the first member and the second member relatively into and out of contact with each other to cause a sheet stopped at a predetermined position to be pinched between the first member and the second member and creased. An edge portion of any one of the first member and the second member has an arcuate shape.

Abstract: A creasing device includes a creasing unit that creases sheets on a one-by-one basis, which is conveyed to a folding device of a subsequent stage, a sheet detection unit that detects a position of a sheet delivered to the creasing device and a control unit that obtains reference information of a fold-position for the folding device and performs control of a stop position of the sheet according to reference information of the fold position, thereby adjusting a crease position.

Abstract: A creasing device includes: a first member on which a linear convex-edged blade is formed in a direction perpendicular to a sheet conveying direction; a second member on which a concave-edged blade pairing with the convex-edged blade is formed; and a drive unit that drives the first and second members to relatively come close to and away from each other, thereby making a crease on the sheet, wherein in a standby state, the drive unit keeps faces of the first member and second member not parallel; and in making a crease on the sheet, causes the convex-edged blade and the concave-edged blade to have point contact with each other via the sheet held therebetween so as to initiate a creasing movement by a rotation movement thereof.

Abstract: An image forming apparatus includes an image forming unit that forms an image on a recording medium; a conveying unit that conveys the recording medium on which the image is formed; a crease forming unit that performs a crease forming process on the conveyed recording medium; a determining unit that determines whether or not the recording medium is a predetermined recording medium; and a control unit that prohibits the crease forming process from being performed by the crease forming unit when the determining unit determines that the recording medium is the predetermined recording medium.

Abstract: A paper transport device is configured to independently drive a paper ejecting roller when predetermined abnormal events occur. When paper-jamming occurs and if no paper is present downstream of a jammed paper or a preceding paper that is present most downstream is located upstream of a predetermined position, the paper ejecting roller is stopped to prevent ejection of papers outside of the paper transport device. When paper-jamming occurs and if a preceding paper that is present most downstream is located downstream of the predetermined position, the paper ejecting roller is independently driven to complete ejection of the preceding paper.

Abstract: A conveying device that conveys a sheet bundle with a flattened back-face portion includes a first conveying unit, a driving unit, and a second conveying unit. The first conveying unit retracts to a position where no driving force is exerted on the sheet bundle before a leading end of the sheet bundle formed in a flat spine shape enters, and abuts on the sheet bundle to exert conveying force after the leading end of the sheet bundle passes a conveying position. The driving unit moves the first conveying unit to retract to the position and to abut on the sheet bundle. The second conveying unit is positioned on an upstream side of the first conveying unit in a sheet bundle conveying direction and conveys the sheet bundle towards the first conveying unit.

Abstract: An spine formation device includes a sheet conveyer that conveys the bundle of folded sheets in a sheet conveyance direction with a folded portion of the bundle forming front end portion thereof, first and second sandwiching units disposed downstream from the sheet conveyer, a contact member disposed downstream from the second sandwiching unit, against which the folded portion of a bundle of folded sheets is pressed, and a controller. The controller stops the sheet conveyer after the bundle is transported a predetermined distance from a contact position between the contact member and the folded portion of the bundle, causing the bundle to bulge, and causes the first and second sandwiching units to squeeze the bulging of the bundle of folded sheets in a thickness direction sequentially with the folded portion of the bundle pressed against the contact member to form a spine of the bundle.

Abstract: A spine formation device includes a sheet conveyer, a clamping unit disposed downstream from the sheet conveyer in a sheet conveyance direction, for squeezing a folded portion of a bundle of folded sheets, a contact member against which the folded portion of the bundle is pressed, disposed downstream from the clamping unit, and a controller to cause the bundle of folded sheets to bulge by stopping the sheet conveyer after the bundle of folded sheets is transported a predetermined conveyance distance from a contact position between the contact member and the folded portion of the bundle and to cause the clamping unit to squeeze a bulging portion of the bundle created between the sheet conveyer and the contact member with the folded portion pressed against the contact member. The predetermined distance is set in accordance with a predetermined sheet-related variable.

Abstract: A bookbinding system that includes: a center folding unit configured to perform center folding on an integrated sheet bundle; an additionally folding unit configured to additionally perform folding of a folded portion of the center-folded sheet bundle; a back surface forming unit configured to form a back surface on the sheet bundle by pressing a front end of the folded portion of the center-folded sheet bundle and both surfaces of the sheet bundle; and a control unit configured to change the content of additionally folding according to whether to perform the back surface forming or not.

Abstract: An spine formation device includes a sheet conveyer to transport a bundle of folded sheets with a folded portion of the bundle of folded sheets forming a front end portion, a sandwiching member to sandwich and squeeze the bundle of folded sheets in a direction of thickness of the bundle of folded sheets, and a spine formation unit disposed downstream from the sandwiching member in the sheet conveyance direction, to flatten the folded portion of the bundle of folded sheets held by the sandwiching member. The spine formation unit presses the folded portion of the bundle of folded sheets projecting a predetermined length from the sandwiching member in the sheet conveyance direction in a reverse direction of the sheet conveyance direction while moving in a direction perpendicular to a longitudinal direction of the folded portion of the bundle of folded sheets.

Abstract: An spine formation device includes a sheet conveyer that conveys the bundle of folded sheets with a folded portion of the bundle of folded sheets forming a front end portion of the bundle of folded sheets, a spine formation unit disposed downstream from the sheet conveyer in a sheet conveyance direction for forming the spine of the bundle of folded sheets by squeezing the folded portion of the bundle from a folded leading side, a front side, and a back side of the bundle, a discharge unit to discharge the bundle of folded sheets outside the spine formation device, disposed downstream form the spine formation unit in the sheet conveyance direction, and a controller to cause the spine formation unit to operate in one of multiple selectable control modes for controlling the spine formation unit in accordance with at least one of multiple predetermined sheet-related variables.