Abstract: 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.

Abstract: Provided is a sheet folding device including a folding roll that is rotatably provided and includes a large diameter portion of which a diameter is greater than a diameter of another portion, and performs a folding process while pressing the large diameter portion onto a sheet, and a contact portion displacement unit that makes a position of a contact portion that is a portion coming into contact with the large diameter portion in the sheet when the sheet on which the folding process has been performed by the folding roll passes through the folding roll again different from a position of the contact portion when the sheet passes through the folding roll for the last time.

Abstract: Provided is a sheet folding device including a folding roll that has a convex portion spirally provided on an outer periphery surface and is rotatably provided, and performs a folding process while pressing the convex portion on a sheet, and a phase change unit that makes a phase of the folding roll when the sheet on which the folding process is performed by the folding roll passes through the folding roll again different from a phase when the sheet passes through the folding roll for the last time.

Abstract: A sheet processing apparatus includes a sheet stacking unit, a binding unit, a folding unit, a conveyance unit, a press unit, a grasping unit, and a control unit. The binding unit performs binding processing on a sheet bundle stacked in the sheet stacking unit. The conveyance unit conveys a sheet bundle folded by the folding unit. The press unit presses a fold line portion of the conveyed sheet bundle from a direction perpendicular to a surface of a front page of the sheet bundle while moving along the fold line portion. The grasping unit is switched between a first state in which the grasping unit fixes the sheet bundle in position and a second state in which the grasping unit does not grasp the conveyed sheet bundle. The control unit shifts the grasping unit to the first state and causes the press unit to press the sheet bundle.

Abstract: When sheets (1, 2) with different sizes are processed to a mail item, sheets (1, 2) with different sizes in conveying direction are supplied along first and second conveyor tracks, gathered into a stack and then folded. The folding of the stacked set (7) takes place with at least one predetermined folding length (a). In response to a difference between the folding length (a) and the size of the sheet (2) of the second size, which is within a predetermined range, the conveyor tracks (5, 6) are controlled by the control structure (9) for combining at least the sheets (1, 2) with leading edges (10, 11) at a mutual distance in the conveying direction (3) and with trailing edges (12, 13) at a mutual distance in the conveying direction (3) to form the set (7). From the combining until the folding, the sheets (1, 2) are mutually fixed and during folding, at least one fold (14) is provided in the sheets (1, 2).

Abstract: A sheet processing apparatus includes a sheet stacking unit, a binding unit, a folding unit, a conveyance unit, a press unit, a grasping unit, and a control unit. The binding unit performs binding processing on a sheet bundle stacked in the sheet stacking unit. The folding unit folds the sheet bundle that is subjected to binding processing. The conveyance unit conveys the folded sheet bundle. The press unit presses a fold line portion of the conveyed sheet bundle. The grasping unit is separate from the conveyance unit and switches between a first state in which the grasping unit grasps the conveyed sheet bundle to fix the sheet bundle in position and a second state in which the grasping unit does not grasp the conveyed sheet bundle. The control unit shifts the grasping unit to the first state and causes the press unit to press the sheet bundle.

Abstract: A folded spine of a booklet held by a pair of opposing holding members is deformed by entering a pressing member into a gap between the pair of holding members and bringing the pressing member into pressure contact with the folded spine. In consequence, the folded spine is prevented from receiving an excessive pressing force, and a smooth surface with a width substantially equal to the thickness of the booklet is thus formed on the folded spine, whereby a booklet with a good appearance can be made.

Abstract: A printing system which is capable of performing square back processing and has a mechanism that makes it possible to prevent occurrence of a new trouble of inadvertently creating a saddle-stitched brochure defective in appearance and/or stackability, which is unexpected by an operator. A printing apparatus receives plural jobs including a saddle-stitch job for creating a saddle-stitched brochure of a predetermined kind. In the saddle-stitch job, saddle-stitch processing and square back processing are carried out. The square back processing is performed by a saddle-stitching machine. The saddle-stitching machine forms a flat surface on the back of a saddle-stitched brochure. A controller permits or inhibits creating the saddle-stitched brochure of the predetermined kind for a job based on whether the job meets a predetermined condition.

Abstract: A folded spine of a booklet held by a pair of opposing holding members is deformed by entering a pressing member into a gap between the pair of holding members and bringing the pressing member into pressure contact with the folded spine. In consequence, the folded spine is prevented from receiving an excessive pressing force, and a smooth surface with a width substantially equal to the thickness of the booklet is thus formed on the folded spine, whereby a booklet with a good appearance can be made.

Abstract: A sheet processing apparatus includes a pushing member, a drive device, a first conveyance unit, a second conveyance unit provided on a downstream side of the first conveyance unit, a first detection unit, a second detection unit, and a control unit. The drive device moves the pushing member to push a portion of a sheet bundle to fold the sheet bundle. The first conveyance unit uses a roller pair to convey the folded sheet bundle folded. The second conveyance unit conveys the sheet bundle. The first detection unit detects an amount by which the pushing member is moved by the drive device. The second detection unit detects an amount by which the sheet bundle is conveyed by the first conveyance unit. The control unit separates the roller pair based on the amounts detected by the first and second detection units.

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: There are provided an image processing apparatus and its control method in which sheet size/type and options can be set every image without reducing the number of images written onto one index sheet. The options include image processes such as addition of a date, VIVID-photo, noise cancellation, automatic photograph correction, face-brightening correction, red-eye correction, etc. Only for the user who desires, a sheet SH2 is used in addition to a conventional index sheet. In the sheet SH2, there can be set every image the sheet size/type and the options of the image processes such as addition of a date, VIVID-photo, noise cancellation, automatic photograph correction, face-brightening correction, red-eye correction, etc.

Abstract: According to an embodiment, there is provided a sheet finishing apparatus including a folding roller that nips the middle of bundle of sheets and forms a fold line, a fold reinforcing roller that reinforces the fold line by moving along the fold line while applying a pressure to the fold line, a stack tray that stacks the bundle and a control unit that sets the number of times of fold reinforcing performed by the fold reinforcing roller as a first number when it is determined that a quantity of stacked bundle on the stack tray is less than a predetermined standard quantity which is set to be less than a maximum stack quantity and sets the number of times of the fold reinforcing as a second number greater than the first number when it is determined that a quantity of the stacked bundle is greater than the predetermined standard quantity.

Abstract: A sheet processing apparatus includes a holding portion that holds a booklet, which includes folded sheets, by a pair of holding members, a pressing portion having a first pressing member, which is brought into contact with a spine of a booklet held by the holding portion so as to perform a deforming process to the spine, and a second pressing member having a thickness, in the thickness direction of the booklet, greater than that of the first pressing member, a moving portion that moves the pressing member along the spine, and a controlling portion that changes the first pressing member to the second pressing member, and increases a deformation amount from the spine before the deformation to a pressing position in the pressing direction where the second pressing member presses the spine, when the thickness of the booklet held by the holding portion exceeds a predetermined thickness.

Abstract: For effective achievement of an increase in productivity, prolongation of the life cycle of a consumable part, a decrease in the running cost, a lighter burden on the operator's work, and a reduction in spending on plants and equipment, a sheet transport apparatus comprises: a folding cylinder (11) for transporting sheets one by one or as a stack of a plurality of the sheets; a jaw cylinder (12) or a reduction cylinder (13) for holding the sheets by alternate ones of holding means and transporting the sheets when the sheets are transported as the stack of the plurality of sheets; an upper transfer cylinder (14) opposing the jaw cylinder or the reduction cylinder; a lower transfer cylinder (15) opposing the jaw cylinder or the reduction cylinder; and switching means for transporting the sheets from the jaw cylinder or the reduction cylinder to the upper transfer cylinder and the lower transfer cylinder, while allocating the sheets to the upper transfer cylinder and the lower transfer cylinder, when the sheets

Abstract: A sheet processing apparatus that performs bookbinding processing on a folded sheet bundle, includes a holding portion configured to hold a folded sheet bundle, and a pressing member configured to press a folded spinal portion of the sheet bundle held by the holding portion. At least one of the holding portion and the pressing member can move in a direction to approach each other along a surface of the sheet held by the holding portion to press the folded spinal portion of the sheet bundle.

Abstract: A spine formation device includes a sheet conveyer, a presser, and a spine formation member. The sheet conveyer conveys a bundle of folded sheets with a folded portion of the bundle of sheets forming a front end portion of the bundle of sheets. The presser is disposed downstream from the sheet conveyer in a sheet conveyance direction in which the sheet conveyer conveys the bundle of sheets. The presser is movable to press opposed sides of the front end portion of the bundle of sheets. The spine formation member is movably disposed downstream from the presser in the sheet conveyance direction. The spine formation member includes a groove portion that contacts and positions the bundle of sheets to define an amount by which the bundle of sheets protrudes from the presser and a spine formation face that forms a spine at the folded portion of the bundle of sheets.

Abstract: A sheet folding apparatus includes: a saddle-stitching unit configured to stitch a center of a sheet bundle; a folding unit configured to fold the sheet bundle at the center to form a fold; a loading base onto which the sheet bundle conveyed from the folding unit is loaded; a nipping plate configured to be pressed to and separated from the loading base in parallel to the loading base and to nip the sheet bundle loaded onto the loading base; and first and second rollers that move along a direction of the fold while nipping and pressing the fold of the sheet bundle nipped by the nipping plate to reinforce the fold. Here, a surface, which faces the loading base, of the nipping plate is provided with an elastic member.

Abstract: An spine formation device includes a sheet conveyer, a contact member including a first row of grooves provided in a contact surface thereof to house a projection projecting from a folded portion of a bundle of folded sheets, a driving unit to move the contact member, first and second sandwiching units to squeeze the bundle, a discharge unit, and a controller. The first row of grooves extends in parallel to the folded portion of the bundle and includes at least a first pair of grooves inclined in different directions with an interval therebetween varying in size with location of the grooves in a first direction perpendicular to a sheet conveyance direction. The contact member is moved to change the size of interval between the first pair of grooves at a position aligned with the projection projecting from the folded portion of the bundle of folded sheets.

Abstract: A sheet folding apparatus includes: a saddle-stitching unit configured to stitch a center of a sheet bundle; a folding unit configured to fold the sheet bundle at the center to form a fold; a loading base onto which the sheet bundle conveyed from the folding unit is loaded; a nipping plate configured to be pressed to and separated from the loading base in parallel to the loading base and to nip the sheet bundle loaded onto the loading base; and first and second rollers that move along a direction of the fold while nipping and pressing the fold of the sheet bundle nipped by the nipping plate to reinforce the fold. Here, a surface, which faces the loading base, of the nipping plate is provided with an elastic member.

Abstract: A method of making magazine formats in the form of signatures that include a flat 3-D piece that is die-cut from a web on a web press, which produces a plurality of such identical signatures as part of a high speed operation. The flat 3-D piece is located at the upper edge of one sheet and is freed from the remainder of the page on which it is die-cut when the lateral edges of the folded signature are trimmed.

Abstract: A sheet finisher of the invention includes a saddle stitch unit configured to stitch a center of a sheet bundle in which printed sheets are bundled, a fold unit configured to fold the center stitched by the saddle stitch unit and to form a fold line, and a fold reinforcing unit configured to reinforce the fold line formed by the fold unit, the fold reinforcing unit includes a placement table on which the sheet bundle transported from the fold unit is placed, and a roller unit that includes a reinforce roller and moves the reinforce roller along a direction of the fold line while pressing it to the fold line, and the placement table is provided with a groove-like edge clearance along an edge of the sheet bundle.

Abstract: A sheet processing apparatus configured to bind a sheet bundle includes a folding portion configured to fold the sheet bundle, a sheet processing portion provided upstream of the folding portion and configured to form a groove at a fold position of at least one sheet of the sheet bundle, and a controller configured to control an operation of the sheet processing portion. The controller controls an operation of the sheet processing portion such that a width of a groove formed on a sheet located on an outer side of the folded sheet bundle is larger than that of a groove formed on a sheet located on an inner side of the folded sheet bundle.

Abstract: A creasing device includes a feeding mechanism, a creasing mechanism, sensors, and an aligning mechanism. The feeding mechanism conveys paper on which an image has been formed in a post-processing apparatus main body direction. The creasing mechanism makes a crease on the paper. The sensors detect a deviation of the paper with respect to the feeding direction. The aligning mechanism, based on an amount of deviation in a result of a detection by the sensors, causes the creasing mechanism to rotate in such a way that the creasing mechanism is aligned parallel to a crease direction of the paper.

Abstract: A sheet processing apparatus of the invention includes a folding mechanism that includes paired folding rollers, presses a sheet to a nip portion of the paired folding rollers from a direction orthogonal to a transport direction, and folds the sheet by rotating the paired folding rollers. Further, there are provided a drive motor capable of making positive rotation and reverse rotation, a variable speed mechanism to convert a rotation force of the drive motor into a rotation output in a single direction and with a low speed or a high speed by changing a rotation direction of the drive motor, a transmission mechanism to transmit the rotation output in the single direction to the paired folding rollers, and a control unit to control the rotation direction of the drive motor and to change the rotation speed of the paired folding rollers.

Abstract: In a sheet creaser, when a sheet is conveyed to a folding unit by a conveyer unit, the folding unit folds the sheet and a pressing unit presses the folded sheet by sliding in a direction substantially perpendicular to a sheet conveying direction. A switching unit switches the conveyer unit between a first position to convey the sheet and a second position unable to convey the sheet. A driving unit drives both the switching unit and the pressing unit.

Abstract: A sheet processing apparatus includes a folding apparatus which folds a sheet bundle, a switching portion which switches a nipping pressure of the folding apparatus against the sheet bundle, and a flattening apparatus which presses and flattens a folded-back portion of the folded sheet bundle. The switching portion operates such that the nipping pressure of the folding apparatus against the sheet bundle when the flattening processing is executed becomes weaker than that of the folding apparatus when the flattening processing is not executed.

Abstract: A saddle-stitched brochure comprising a collated sheet stack (P1 to P3) folded in two at its center portion and stitched with wire at least two positions spaced from each other on the folding line (1a), characterized in that a small printed material (2, 2a) is arranged between the adjacent sheets (P2, P3) of the sheet stack (P1 to P3) and inserted between the adjacent stitched portions (3, 3) on the folding line (1a) and folded along the folding line (1a) together with the sheet stack (P1 to P3) so as to be held in the brochures (1).

Abstract: In a sheet post-processing apparatus that folds a sheet bundle, a folding roller drive motor that drives folding rollers is PWM driven such that its speed is varied in each control during the period until a blade contacts the sheet bundle, during the period when the sheet bundle is conveyed to a discharge port, during discharge operation, and during return of the motor to its home position.

Abstract: A postprocessing unit of a postprocessing device performs a postprocess including a preset folding process at a set folding position, with respect to recording sheets. A setting unit of the postprocessing device sets an adjustment amount of the folding position on the basis of a target value of the folding position, a measured value of the folding position after the folding process, and sheet quality information of the recording sheets. An adjusting unit of the postprocessing device adjusts the folding position of the postprocessing unit on the basis of the adjustment amount set by the setting unit. An adjustment control unit of the postprocessing device controls the adjustment by the adjusting unit on the basis of the adjustment amount set by the setting unit.

Abstract: A sheet processing apparatus includes a winding unit configured to wind a continuous sheet, a binding unit configured to bind the continuous sheet that is wound and stacked by the winding unit, and a first cutting unit configured to cut the continuous sheet that is bound by the binding unit in a state that the continuous sheet is wound by the winding unit.

Abstract: A method of making magazine formats in the form of signatures that include a flat 3-D piece that is die-cut from a web on a web press, which produces a plurality of such identical signatures as part of a high speed operation. The flat 3-D piece is located at the upper edge of one sheet and is freed from the remainder of the page on which it is die-cut when the lateral edges of the folded signature are trimmed.

Abstract: A receiving member for receiving the leading end of sheet on a sheet placing table is disposed movably along the upper surface of the sheet placing table within a specified range including a first position located at the other end of the sheet placing table and distanced from a carry-in opening at least by the length of the sheet, and an operation control unit causes the receiving member to move to a second position where the trailing end of the sheet received by the receiving member slips under the carry-in opening.

Abstract: A sheet folding apparatus including: a conveyance device having a first pair of rollers for nipping and conveying a paper sheet; a folding device disposed downstream of the conveyance device in a paper sheet conveyance direction, the folding device having a second pair of rollers for nipping and conveying the paper sheet, wherein the conveyance device conveys the paper sheet to the folding device by making the paper sheet bent toward the folding device, and the folding device conveys the bent paper sheet to fold the paper sheet; and a folding assist member for pushing the paper sheet so that the paper sheet moves toward the folding device, the folding assist member being pivotally arranged to be capable of rotating downstream of the conveyance device in the conveyance direction.

Abstract: A sheet loader for loading a folded sheet bundle provided from a sheet bundle provider with a folded edge of the folded sheet bundle in a lead, including: an undersurface support configured to support an undersurface of the folded sheet bundle provided from the sheet bundle provider; a folded edge blocker configured to take a blocking position to block the folded edge of the folded sheet bundle on the undersurface support and a releasing position to release the folded sheet bundle; and a joint configured to evacuate from an orbit of the folded edge blocker returning from the releasing position to the blocking position, the joint is configured to join the undersurface support with the folded edge blocker at the blocking position after the returning to the blocking position.

Abstract: A creasing device includes a feeding mechanism, a creasing mechanism, sensors, and an aligning mechanism. The feeding mechanism conveys paper on which an image has been formed in a post-processing apparatus main body direction. The creasing mechanism makes a crease on the paper. The sensors detect a deviation of the paper with respect to the feeding direction. The aligning mechanism, based on an amount of deviation in a result of a detection by the sensors, causes the creasing mechanism to rotate in such a way that the creasing mechanism is aligned parallel to a crease direction of the paper.

Abstract: A sheet processing apparatus configured to bind a sheet bundle includes a folding portion configured to fold the sheet bundle, a sheet processing portion provided upstream of the folding portion and configured to form a groove at a fold position of at least one sheet of the sheet bundle, and a controller configured to control an operation of the sheet processing portion. The controller controls an operation of the sheet processing portion such that a width of a groove formed on a sheet located on an outer side of the folded sheet bundle is larger than that of a groove formed on a sheet located on an inner side of the folded sheet bundle.

Abstract: A sheet finisher of the invention includes a saddle stitch unit configured to stitch a center of a sheet bundle in which printed sheets are bundled, a fold unit configured to fold the center stitched by the saddle stitch unit and to form a fold line, and a fold reinforcing unit configured to reinforce the fold line formed by the fold unit, the fold reinforcing unit includes a placement table on which the sheet bundle transported from the fold unit is placed, and a roller unit that includes a reinforce roller and moves the reinforce roller along a direction of the fold line while pressing it to the fold line, and the placement table is provided with a groove-like edge clearance along an edge of the sheet bundle.

Abstract: A sheet processing apparatus according to the present invention including a saddle-stitcher configured to fold and discharge a sheet supplied from an image forming apparatus, and an assisting mechanism arranged in a sheet carrier path extending from the image forming apparatus to the saddle-stitcher and configured to form a folding line on the sheet in a first direction orthogonal to a direction of the carrying of the sheet in order to assist folding of the sheet. The assisting mechanism has a disc-shaped roller blade rotatably attached to a moving body that is movable in the first direction.

Abstract: A sheet processing apparatus of the invention includes a folding mechanism that includes paired folding rollers, presses a sheet to a nip portion of the paired folding rollers from a direction orthogonal to a transport direction, and folds the sheet by rotating the paired folding rollers. Further, there are provided a drive motor capable of making positive rotation and reverse rotation, a variable speed mechanism to convert a rotation force of the drive motor into a rotation output in a single direction and with a low speed or a high speed by changing a rotation direction of the drive motor, a transmission mechanism to transmit the rotation output in the single direction to the paired folding rollers, and a control unit to control the rotation direction of the drive motor and to change the rotation speed of the paired folding rollers.

Abstract: In a sheet post-processing apparatus that folds a sheet bundle, a folding roller drive motor that drives folding rollers is PWM driven such that its speed is varied in each control during the period until a blade contacts the sheet bundle, during the period when the sheet bundle is conveyed to a discharge port, during discharge operation, and during return of the motor to its home position.

Abstract: A sheet bending apparatus and a sheet postprocessing apparatus are provided for improved alignment of recording sheets during center-folding. A center-folding unit mounted in a sheet postprocessing apparatus performs a center-folding processing to a stack of recording sheets aligned on their sides and placed in a sheet holding member. Side aligning is performed near a central portion in a sheet conveyance direction of the sheet holding member. The center-folding unit includes: two upper end aligning members positioned upstream in the sheet conveyance direction on the sheet holding member and movable equally in opposite width directions of the sheet holding member; and a pair of lower side end aligning members positioned on downstream in the sheet conveyance direction on the sheet holding member and are movable equally in opposite width directions of the sheet holding member and independently from the upper end aligning members.

Abstract: A booklet-loading device includes: a carry-out unit that conveys plural of booklets sequentially; and a transfer unit that transfers the plural of booklets sequentially conveyed from the carry-out unit, and arranges the plural of booklets in a partly overlapped state; a loaded unit that is loaded with the booklets transferred by the transfer unit; and a transfer control unit that controls a transfer amount per booklet in the transfer unit to a transfer amount depending on a quantity of booklets loaded on the loaded unit.

Abstract: In a sheet post-processing apparatus to perform a folding processing to a sheet bundle, a folding roller drive motor to drive a pair of folding rollers is PWM driven, and its speed is changed according to the sheet type or sheet size and between a period before a blade comes in contact with the sheet bundle, a period when the blade is being inserted between the folding rollers after coming in contact with the sheet bundle, and a period when folding is being performed by the folding rollers.

Abstract: A sheet processing apparatus including: a stapler; a conveying path, which conveys a sheet to the stapler; a bundle forming device to form a sheet bundle in the conveying path, the bundle forming device having a pinch device, which successively pinches an upstream end portion of the sheet to pinch plural sheets integrally; a control portion, which controls the stapler and the bundle forming device to staple the sheet bundle selectively between at one end of the sheet bundle for the side stitching and on the fold line of the sheet bundle for the saddle stitching; a discharging device, which discharges the sheet bundle stapled at the one end onto a stacking portion, a two-fold device, which folds the sheet bundle stapled on the fold line in two along the fold line, and a joining device, which joins the sheet bundle folded by the two-fold device into the discharging device.

Abstract: A sheet folding apparatus, including: a sheet folder configured to fold a sheet bundle; a sheet tray configured to support the sheet bundle folded by the sheet folder; a first frame configured to support the sheet folder; a second frame configured to movably support the first frame and the sheet tray; a first sensor unit supported by the second frame, configured to change its condition depending on presence of the sheet bundle on the sheet tray; a second sensor unit supported by the first frame, configured to detect the condition of the first sensor unit; and a controller supported by the first frame, configured to control the sheet folder according to the detection of the second sensor unit.

Abstract: A folded portion flattening unit includes: a sheet conveyance unit that conveys a booklet including a folded sheet with a folded portion in a lead toward a predetermined conveyance direction; a sheet stopper that stops the booklet conveyed by the sheet conveyance unit at a predetermined position; a pair of booklet grasping members that clamp and grasp the booklet stopped by the sheet stopper at both faces of the booklet; a pressing member that flattens a curve at a front end of the folded portion being grasped by the booklet grasping members, by pressing the front end toward a direction opposite to the conveyance direction; and an opening amount setting unit that sets an opening amount of an opening portion between the pair of booklet grasping members, when the conveyed booklet is sandwiched between the pair of booklet grasping members.

Abstract: A postprocessing apparatus includes: a housing to which a recording sheet is fed from a predetermined upstream device; a first postprocessing mechanism mounted in the housing and adapted for performing a predetermined first postprocessing to the recording sheet; a second postprocessing mechanism selectively mountable in the housing, and is provided with a predetermined driver, the second postprocessing mechanism being adapted for performing a predetermined second postprocessing to the recording sheet; a conveyance passage provided in the first postprocessing mechanism and adapted for conveying the recording sheet to the second postprocessing mechanism when the second postprocessing mechanism is mounted in the housing; and a conveying member provided in the conveyance passage and adapted for conveying the recording sheet. The conveying member is driven by a transmission of a driving force from the driver of the second postprocessing mechanism.

Abstract: A sheet processing apparatus for covering a sheet bundle with a cover sheet includes a creasing unit for making a crease along an end portion of the cover sheet adjacent the edge of the sheet bundle opposite the spine edge of the sheet bundle. The sheet processing apparatus further includes a folding-back unit for folding-back the end portion of the cover sheet along the crease made by the creasing unit.

Abstract: A sheet bundle stored in a sheet storage portion is pushed from a predetermined folded position with a first pushing plate, and the sheet bundle is normally conveyed along with the first pushing plate and plunged into a nip between first folding rollers to make a fold. The first folding rollers are reversely rotated while the first pushing plate is retreated, and the sheet bundle with the fold is reversely conveyed and returned to the sheet storage portion. Then, a second pushing plate pushes the sheet bundle, conveyed through a U-shape conveyance path, from a backside of the fold to reversely fold the sheet bundle, and the sheet bundle is completely folded. Therefore, the sheet bundle having good appearance can be realized in good bundle folding processing.