Patent ID: 8186663

Claim:
A spine formation device comprising: a sheet conveyer that conveys a bundle of folded sheets with a folded portion of the bundle of folded sheets forming a front end portion of the bundle of folded sheets; a presser disposed downstream from the sheet conveyer in a sheet conveyance direction in which the sheet conveyer conveys the bundle of folded sheets, the presser movable to press opposed sides of the front end portion of the bundle of folded sheets conveyed with the sheet conveyer; and a spine formation member movably disposed downstream from the presser in the sheet conveyance direction, the spine formation member comprising a groove portion and a spine formation face, the groove portion contacting and positioning the bundle of folded sheets to define an amount by which the bundle of folded sheets protrudes from the presser, the spine formation face forming a spine at the folded portion of the bundle of folded sheets.