Patent ID: 7261507
Filing Date: 2007-08-28
Classification: B42B,B65H

Abstract:
1. A book binding system for a saddle-stitched bound booklet, comprising: a sheet feeding section feeding sheets or sets of sheets one by one; a sheet folding section sequentially receiving a sheet or a set of sheets from the sheet feeding section and folding the sheet or the set of sheets along the center line thereof; a sheet stacking section stacking the sheet or the set of sheets folded by the sheet folding section in such a manner that the folded sheets or the folded sets of sheets are aligned with each other with respect to the fold lines thereof; a sheet stitching section receiving a stack of the sheets or the sets of sheets from the sheet stacking section each time the predetermined number of the sheets or the sets of sheets are stacked in the sheet stacking section, and stitching the stack of the sheets or the sets of sheets at the fold line thereof; and the sheet folding section further comprising: a sheet positioning means for sequentially receiving the sheet or the set of sheets from the sheet feeding section and positioning the sheet or the set of sheets in place; a sheet conveying path extending from the sheet positioning means to the sheet stacking section, the sheet positioning means positioning the sheet or the set of sheets in such a manner that the center line of the sheet or the set of sheets aligns with the center line of the sheet conveying path; a fold line forming means arranged at the entrance of the sheet conveying path for forming an inverted V-shaped fold line on the sheet or the set of sheets along the center line thereof while conveying the sheet or the set of sheets; and a folding means arranged at the downstream side of the fold line forming means for folding the sheet of the set of sheets along the fold line while conveying the sheet or the set of sheets received from the fold line forming means; a control section controlling operation of the sheet feeding section, the sheet folding section and the sheet stitching section; a frame; and the sheet positioning means of the sheet folding section comprising: a sheet positioning table attached to the frame for sequentially receiving the sheet or the set of sheets from the sheet feeding section and positioning the sheet or the set of sheets in place; the fold line forming means of the sheet folding section further comprising: upper and lower horizontal rotating shafts attached to the frame at the entrance of the sheet conveying path so as to be arranged one above the other with the sheet conveying path therebetween and extending in the direction transverse to the sheet conveying path; a drive mechanism attached to the frame for rotating the upper horizontal rotating shaft; upper and lower creasing rollers fixed to the upper and lower horizontal rotating shafts, respectively, the upper and lower creasing rollers being disposed at the position corresponding to the center line of the conveying path and bringing their outer periphery surfaces into contact with each other, the upper creasing roller being provided with a groove extending about the outer periphery thereof, the lower creasing roller being provided with a protrusion extending about the outer periphery thereof correspondingly with the groove, the groove and the protrusion being disposed at a position corresponding to the center line of the conveying path, the sheet or the set of sheets on the sheet positioning table being nipped between the upper and lower creasing rollers and provided with an inverted V-shaped fold line thereon; at least one horizontal support shaft attached to the frame at a downstream side of the horizontal rotating shafts; a guide roller rotatably attached to the at least one horizontal support shaft at a position corresponding to the center line of the sheet conveying path, an outer periphery edge thereof upwardly pushing the fold line of the sheet or the set of sheets traveling on the sheet conveying path; the folding means of the sheet folding section further comprising: a pair of vertical support shafts attached to the frame at the exit of the sheet conveying path and extending downwardly from the frame across the sheet conveying path at the both sides of the center line of the sheet conveying path; a pair of press rollers rotatably attached to the lower ends of the vertical support shafts, each of the press rollers being composed of a large radius portion and a small radius portion connecting to the underside of the large radius portion, the press rollers bringing their outer periphery surfaces into contact with each other at a position corresponding to the center line of the sheet conveying path, the sheet or the set of sheets being nipped at its peripheral portion folded along the fold line between the press rollers and fed downstream; pulleys fixed to the upper horizontal rotating shaft at both sides of the upper creasing roller; and a first endless belt extending between the pulley and the small radius portion of the press roller at one side of the center line of the sheet conveying path, and a second endless belt extending between the pulley and the small radius portion of the press roller at the other side of the center line of the sheet conveying path, portions of the first and second endless belts which travel in a feeding direction of the sheet or the set of sheets contacting with a top surface of the sheet or the set of sheets and gradually narrowing the spacing therebetween towards the exit of the sheet folding section; whereby the sheet or the set of sheets is folded into an inverted V-shape along the center line thereof by being passed between the upper and lower creasing rollers, conveyed along the sheet conveying path by the at least one guide roller and the first and second endless belts and passed between the pair of press rollers.