SHEET PROCESSING APPARATUS AND IMAGE FORMING APPARATUS PROVIDED THEREWITH AND SHEET PROCESSING METHOD

• US 20070126165A1
• Filed: 11/07/2006
• Published: 06/07/2007
• Est. Priority Date: 11/11/2005
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Kato, Hitoshi, Chikugo, Youichi, Fujita, Keiko, Kawata, Wataru
• Granted Patent: US 7,597,311 B2
• Time in Patent Office: Days
• US Class Current: 270/37
• CPC Class Codes: B65H 2301/163 Bound or non bound, e.g. stapled or non stapled stacking mode
• CPC Class Codes: B65H 45/18 Oscillating or reciprocating blade folders carried on rotary members B65H45/16

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 grollers 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.

Claims

1. A sheet processing apparatus comprising:

a first folding unit which performs folding processing to a predetermined folding position on a sheet or a sheet bundle; and

a second folding unit which folds the sheet or the sheet bundle folded by said first folding unit in an opposite direction to said first folding unit at said predetermined folding position.

2. The sheet processing apparatus according to claim 1,

wherein said first folding unit includes a first folding roller pair which folds the sheet or the sheet bundle while conveying the sheet or the sheet bundle and a first pushing member which pushes the sheet or the sheet bundle toward said first folding roller pair.

3. The sheet processing apparatus according to claim 2,

wherein said first pushing member pushes the sheet or the sheet bundle between said first folding roller pair.

4. The sheet processing apparatus according to claims 2, wherein said second folding unit includes a second folding roller pair which folds the sheet or the sheet bundle while conveying the sheet or the sheet bundle and a second pushing member which pushes the sheet or the sheet bundle toward said first folding roller pair in the opposite direction to said first pushing member at said predetermined folding position.

5. The sheet processing apparatus according to claim 1, further comprising a conveyance path connecting said first folding unit and said second folding unit,

wherein a length of said conveyance path is longer than a length in a conveyance direction of a foldable maximum sheet.

6. The sheet processing apparatus according to claim 5,

wherein said conveyance path has a curved shape.

7. The sheet processing apparatus according to claim 1, further comprising a conveyance path connecting said first folding unit and said second folding unit, wherein a length of said conveyance path is shorter than a length from said predetermined folding position of a foldable sheet to an end portion of the foldable sheet in a conveyance direction.

8. The sheet processing apparatus according to claim 7,

wherein said conveyance path has a curved shape.

9. The sheet processing apparatus according to claim 1, further comprising:

a sheet storage portion in which the sheets are stored; and

a binding unit which binds the sheets stored in said sheet storage portion,

wherein said first folding unit performs the folding processing to the sheets after said binding unit performs binding processing to said predetermined folding position.

10. The sheet processing apparatus according to claim 1, wherein said first folding unit processes the sheet one by one, and

said second folding unit folds the plurality of sheets folded by said first folding unit while superimposing the sheets on top of another.

11. The sheet processing apparatus according to claim 10,

wherein said first folding unit includes a first folding roller pair which folds the sheet while conveying the sheet and a first pushing member which pushes the sheet one by one toward said first folding roller pair.

12. The sheet processing apparatus according to claim 10,

wherein said second folding unit includes a second folding roller pair which folds the sheet or the sheet bundle while conveying the sheet or the sheet bundle and a second pushing member which pushes the sheet or the sheet bundle toward said second folding roller pair in the opposite direction to said first folding roller pair at said predetermined folding position.

13. The sheet processing apparatus according to claim 10, further comprising:

a sheet storage portion in which the sheets folded by said first folding unit are stored; and

a binding unit which binds the sheets stored in said sheet storage portion,

wherein said second folding unit performs the folding processing the sheets after said binding unit performs binding processing to said predetermined folding position.

14. An image forming apparatus comprising:

an image forming portion which forms an image on a sheet; and

a sheet processing apparatus according to any one of claims 1 to 13 which performs processing to the sheet or a sheet bundle on which the image is formed by said image forming portion.

15. A sheet processing method comprising:

a first folding step of folding a sheet or a sheet bundle at a predetermined folded position; and

a second folding step of folding the sheet folded by said first folding step in a nopposite directi onto said first folding step at said predetermined folding position.

16. A sheet processing method comprising:

an image forming step of forming an image on a sheet;

a first folding step of folding the sheet or the sheet bundle on which the image is formed at a predetermined folding position; and

a second folding step of folding the sheet or the sheet bundle folded by said first folding step in an opposite direction to said first folding step at said predetermined folding position.