Sheet processing apparatus and image forming system
A sheet processing apparatus includes a flexure forming unit configured to flex sheets to include a portion on which no fold line is formed in a direction orthogonal to a sheet conveying direction; a first pressing member pair configured to press a flexure portion of the flexed sheets to form a fold line thereon; and a moving unit configured to move a pressing position of the first pressing member pair in the direction orthogonal to the sheet conveying direction.
1. A sheet processing apparatus, comprising:
a flexure forming unit configured to flex sheets to include a portion on which no fold line is formed in a direction orthogonal to a sheet conveying direction;
a first pressing member pair, which is next to the flexure forming unit, configured to press a flexure portion of the flexed sheets to form a fold line thereon; and
a moving unit configured to move a pressing position of the first pressing member pair in the direction orthogonal to the sheet conveying direction.
2. The sheet processing apparatus according to claim 1 , wherein the flexure forming unit includes a second pressing member pair including pressing members that partially press the sheets in the direction orthogonal to the sheet conveying direction to form a fold line on a pressed portion of the sheets and that flex the sheets not to form a fold line on a portion other than the pressed portion.
3. The sheet processing apparatus according to claim 2 , wherein a width of a portion of the sheets pressed by the second pressing member pair is equal to or smaller than half of a sheet width.
4. The sheet processing apparatus according to claim 1 , wherein
the flexure forming unit includes an abutment member pair including abutment members, and
the abutment member pair is configured to abut on the sheets with the abutment members separated from each other to flex the sheets not to form a fold line on the sheets.
5. The sheet processing apparatus according to claim 2 , wherein the second pressing member pair is configured to press the sheets on insides of both ends of the sheets in a sheet width direction.
6. The sheet processing apparatus according to claim 2 , wherein the second pressing member pair is installed with a predetermined distance apart from each of the pressing members.
7. The sheet processing apparatus according to claim 1 , wherein
the flexure forming unit is a roller pair including a pair of roller members arranged to sandwich the sheets therebetween, and
edge portions of the roller members have round shapes, respectively.
8. The sheet processing apparatus according to claim 1 , wherein
the first pressing member pair is configured to start a pressing operation from a predetermined position within a sheet width, and
a position on the sheets pressed by the flexure forming unit during flexing of the sheets includes the predetermined position.
9. The sheet processing apparatus according to claim 1 , wherein
the first pressing member pair is a roller pair having an axis line in a direction orthogonal to a sheet width direction and including a pair of roller members arranged to sandwich a fold line of the sheets therebetween,
the first pressing member pair is configured to press the fold line of the sheets from a predetermined position within a sheet width to one end of the sheets in the sheet width direction, and then press a portion of the fold line not pressed in a previous pressing operation while moving in an opposite direction of the sheet width direction.
10. An image forming system, comprising:
an image forming apparatus configured to form images on sheets, respectively;
a sheet processing apparatus configured to perform a folding process on the sheets each having the image formed by the image forming apparatus; and
the sheet processing apparatus according to claim 1 .