A method of folding a sheet of paper. The method includes folding a strip of paper about in half to form a first folded strip. The method also includes folding the first folded strip about a point that is about two-thirds a length of the first folded strip to form a second folded strip including an exposed portion that is about a third the length of the first folded strip. The method also includes folding the second folded strip about in half to form a third folded strip. The method also includes before folding the third folded strip, applying a spot of glue on the third folded strip. The method also includes folding the third folded strip about in half to form a fourth folded strip.

A method of folding a sheet of paper. The method includes folding a strip of paper about in half to form a first folded strip. The method also includes folding the first folded strip about a point that is about two-thirds a length of the first folded strip to form a second folded strip including an exposed portion that is about a third the length of the first folded strip. The method also includes folding the second folded strip about in half to form a third folded strip. The method also includes before folding the third folded strip, applying a spot of glue on the third folded strip. The method also includes folding the third folded strip about in half to form a fourth folded strip.

According to an example aspect of the present invention, there is provided a method and apparatus for folding a stack of superposed sheets. The method comprises transferring the stack to a folding station, gripping a first part of the stack with a first grip and forming a crease on the stack to facilitate the folding. Then the at least a part of the stack is folded over the first part of the stack that has been gripped by utilizing the crease, the folded stack is gripped with a second grip and the folded stack is transferred from the folding station to a next handling stage and releasing the first grip.

According to an example aspect of the present invention, there is provided a method and apparatus for folding a stack of superposed sheets. The method comprises transferring the stack to a folding station, gripping a first part of the stack with a first grip and forming a crease on the stack to facilitate the folding. Then the at least a part of the stack is folded over the first part of the stack that has been gripped by utilizing the crease, the folded stack is gripped with a second grip and the folded stack is transferred from the folding station to a next handling stage and releasing the first grip.

Each of the sheets is conveyed by a horizontal conveyance unit in a state of being overlapped with a next sheet from above. Each of the sheets is conveyed out of the horizontal conveyance unit in a state of being folded along a fold line with the fold line oriented upward, the fold line extending in a conveyance direction of the horizontal conveyance unit. An oblique conveyance unit receives the sheet from the horizontal conveyance unit and successively conveys the sheets in an oblique downward direction. A sensor is arranged to detect passage of the sheets at a position where steps pass. Each of the steps is formed by two sheets adjacent to each other diverted to the oblique downward direction by the oblique conveyance unit.

A sheet processing apparatus is configured to press a fold line that is formed on a sheet. The sheet processing apparatus includes: a sheet supporting unit configured to support the sheet in a pressing direction for pressing the fold line; a pressing unit configured to press the fold line that is formed on the sheet that is supported by the sheet supporting unit; and a pressing-force generating unit configured to generate a pressing force for pressing the sheet supporting unit against the pressing unit at a central part in a direction along which the fold line is formed.

A sheet processing apparatus is configured to press a fold line that is formed on a sheet. The sheet processing apparatus includes: a sheet supporting unit configured to support the sheet in a pressing direction for pressing the fold line; a pressing unit configured to press the fold line that is formed on the sheet that is supported by the sheet supporting unit; and a pressing-force generating unit configured to generate a pressing force for pressing the sheet supporting unit against the pressing unit at a central part in a direction along which the fold line is formed.

A sheet bonding apparatus includes an electrophotographic unit configured to apply powder adhesive on a sheet by an electrophotographic process, a folding portion configured to fold the sheet on which the powder adhesive has been applied by the electrophotographic unit, and a bonding portion configured to heat the sheet folded by the folding portion to bond the sheet by the powder adhesive, wherein the bonding portion and the folding portion are disposed over the electrophotographic unit.

An image forming apparatus includes an image forming portion, a fixing portion configured to heat and press the sheet conveyed from the image forming portion while nipping and conveying the sheet by a first nip portion to fix toner image to the sheet, a folding portion configured to fold the sheet, and a bonding portion configured to heat and press the sheet folded by the folding portion while nipping and conveying the sheet by a second nip portion to bond the sheet by powder adhesive. A peak value of pressure that the second rotary member pair applies to the sheet in the second nip portion is greater than a peak value of pressure that the first rotary member pair applies to the sheet in the first nip portion.

A paper folding device that folds a planar paper sheet while conveying the paper sheet along a paper sheet conveyance surface includes a pair of first conveyance rollers disposed on an upstream side in a paper sheet conveyance direction, a pair of second conveyance rollers disposed on a downstream side in the paper sheet conveyance direction, a switching gate plate installed on the paper sheet conveyance surface between both pairs of the rollers, a folding plate disposed above the switching gate plate, and a control unit that controls an operation of an entire device.