Patent ID: 8096541

Claim:
A sheet folding apparatus comprising: a sheet supporting member which has an inclined surface to support a stack of sheets; a sheet position adjuster which adjusts a position of the stack of sheets along the inclined surface; a sheet pressing unit which presses the stack of sheets against the inclined surface; a folding unit which folds the stack of sheets pressed by the sheet pressing unit; and a controller which controls the sheet pressing unit to press the stack of sheets on the sheet position adjuster against the inclined surface, and to create a gap between the stack of sheets on the sheet position adjuster and the sheet pressing unit to receive a sheet onto the sheet position adjuster, wherein the sheet pressing unit includes a sheet pressure member and a drive mechanism which moves the sheet pressure member from a standby position apart from the inclined surface to a sheet pressing position close to the inclined surface to press the stack of sheets, and the controller controls the drive mechanism to operate at a first speed for a first kind of sheet and controls the drive mechanism to operate at a second speed higher than the first speed for a second kind of sheet different from the first kind of sheet.