Folded portion flattening unit, post-treatment device, and image forming apparatus

1. A folded portion flattening unit comprising:

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 at a predetermined position, the booklet being conveyed by the sheet conveyance unit;

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 substantially flattens a curve at a front end of the folded portion of the booklet being grasped by the booklet grasping members, by pressing the front end of the folded portion toward a direction opposite to the conveyance direction; and

a grasping force adjustment unit that adjusts grasping force, the grasping force being generated by the pair of booklet grasping members when the pair of booklet grasping members grasp the booklet stopped by the sheet stopper,

wherein the folded portion flattening unit is incorporated into a post-treatment device, the post-treatment device receiving the sheet that an image is formed on by an image forming apparatus connected to the folded portion flattening unit, the post-treatment device folding and delivering the sheet,

the folded portion flattening unit includes a booklet information receiving unit that receives booklet information from the image forming apparatus, the booklet information forming the basis for adjusting the grasping force, and

the grasping force adjustment unit adjusts the grasping force based on the booklet information received by the booklet information receiving unit,

wherein the booklet information is a combination of the number of sheets, a sheet size, a sheet thickness, and a type of sheet.

2. A post-treatment device comprising:

an intermediate treatment unit that folds a sheet to produce a booklet;

a sheet conveyance unit that conveys the booklet with a folded portion in a lead toward a predetermined conveyance direction, the booklet being produced by the intermediate treatment unit;

a sheet stopper that stops the booklet at a predetermined position, the booklet being conveyed by the sheet conveyance unit;

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 substantially flattens a curve at a front end of the folded portion of the booklet being grasped by the booklet grasping members, by pressing the front end of the folded portion toward a direction opposite to the conveyance direction; and

a grasping force adjustment unit that adjusts grasping force, the grasping force being generated by the pair of booklet grasping members when the pair of booklet grasping members grasp the booklet stopped by the sheet stopper,

wherein the post-treatment device includes a booklet information receiving unit that receives booklet information from an image forming apparatus, the booklet information forming the basis for adjusting the grasping force, and

the grasping force adjustment unit adjusts the grasping force based on the booklet information received by the booklet information receiving unit,

wherein the booklet information is a combination of the number of sheets, a sheet size, a sheet thickness, and a type of sheet.

3. An image forming apparatus comprising:

an image forming unit that forms an image on a sheet;

an intermediate treatment unit that folds the sheet to produce a booklet, the image being formed on the sheet by the image forming unit;

a sheet conveyance unit that conveys the booklet with a folded portion in a lead toward a predetermined conveyance direction, the booklet being produced by the intermediate treatment unit;

a sheet stopper that stops the booklet at a predetermined position, the booklet being conveyed by the sheet conveyance unit;

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 substantially flattens a curve at a front end of the folded portion of the booklet being grasped by the booklet grasping members, by pressing the front end of the folded portion toward a direction opposite to the conveyance direction; and

a grasping force adjustment unit that adjusts grasping force, the grasping force being generated by the pair of booklet grasping members when the pair of booklet grasping members grasp the booklet stopped by the sheet stopper,

wherein the image forming apparatus includes a booklet information receiving unit that receives booklet information from the image forming unit, the booklet information forming the basis for adjusting the grasping force, and

the grasping force adjustment unit adjusts the grasping force based on the booklet information received by the booklet information receiving unit,

wherein the booklet information is a combination of the number of sheets, a sheet size, a sheet thickness, and a type of sheet.

4. A folded portion flattening unit comprising:

a sheet conveying means for conveying a booklet including a folded sheet with a folded portion in a lead toward a predetermined conveyance direction;

a sheet stopping means for stopping the booklet at a predetermined position, the booklet being conveyed by the sheet conveying means;

a pair of booklet grasping means for clamping and grasping the booklet stopped by the sheet stopping means at both faces of the booklet;

a pressing means for substantially flattening a curve at a front end of the folded portion of the booklet being grasped by the booklet grasping means, by pressing the front end of the folded portion toward a direction opposite to the conveyance direction; and

a grasping force adjusting means for adjusting grasping force, the grasping force being generated by the pair of booklet grasping means when the pair of booklet grasping means grasp the booklet stopped by the sheet stopping means,

wherein the folded portion flattening unit is incorporated into a post-treatment device, the post-treatment device receiving the sheet that an image is formed on by an image forming apparatus connected to the folded portion flattening unit, the post-treatment device folding and delivering the sheet,

the folded portion flattening unit includes a booklet information receiving means that receives booklet information from the image forming apparatus, the booklet information forming the basis for setting the opening amount, and

the grasping force adjustment means adjusts the grasping force based on the booklet information received by the booklet information receiving means,

wherein the booklet information is a combination of the number of sheets, a sheet size, a sheet thickness, and a type of sheet.

5. A post-treatment device comprising:

an intermediate treatment means for folding a sheet to produce a booklet;

a sheet conveying means for conveying the booklet with a folded portion in a lead toward a predetermined conveyance direction, the booklet being produced by the intermediate treatment means;

a sheet stopping means for stopping the booklet at a predetermined position, the booklet being conveyed by the sheet conveying means;

a pair of booklet grasping means for clamping and grasping the booklet stopped by the sheet stopping means at both faces of the booklet;

a pressing means for substantially flattening a curve at a front end of the folded portion of the booklet being grasped by the booklet grasping means, by pressing the front end of the folded portion toward a direction opposite to the conveyance direction; and

a grasping force adjusting means for adjusting grasping force, the grasping force being generated by the pair of booklet grasping means when the pair of booklet grasping means grasp the booklet stopped by the sheet stopping means,

wherein the post-treatment device includes a booklet information receiving means that receives booklet information from an image forming apparatus, the booklet information forming the basis for adjusting the grasping force, and

the grasping force adjustment means adjusts the grasping force based on the booklet information received by the booklet information receiving means,

wherein the booklet information is a combination of the number of sheets, a sheet size, a sheet thickness, and a type of sheet.

6. An image forming apparatus comprising:

an image forming means for forming an image on a sheet;

an intermediate treatment means for folding the sheet to produce a booklet, the image being formed on the sheet by the image forming means;

a sheet conveying means for conveying the booklet with a folded portion in a lead toward a predetermined conveyance direction, the booklet being produced by the intermediate treatment means;

a sheet stopping means for stopping the booklet at a predetermined position, the booklet being conveyed by the sheet conveying means;

a pair of booklet grasping means for clamping and grasping the booklet stopped by the sheet stopping means at both faces of the booklet;

a pressing means for substantially flattening a curve at a front end of the folded portion of the booklet being grasped by the booklet grasping means, by pressing the front end of the folded portion toward a direction opposite to the conveyance direction; and

a grasping force adjusting means for adjusting grasping force, the grasping force being generated by the pair of booklet grasping means when the pair of booklet grasping means grasp the booklet stopped by the sheet stopping means,

wherein the image forming apparatus includes a booklet information receiving means that receives booklet information from the image forming means, the booklet information forming the basis for adjusting the grasping force, and

the grasping force adjustment means adjusts the grasping force based on the booklet information received by the booklet information receiving means,

wherein the booklet information is a combination of the number of sheets, a sheet size, a sheet thickness, and a type of sheet.