Edge-rounding method and apparatus therefor

An apparatus for rounding edges of workpieces which comprises a conveyor having a support surface for carrying the workpieces thereon, the first set of rotary buffs consisting of a plurality of disk-shaped buffs of the same diameter held over the conveyor, with the center axes of rotation of said buffs extending vertically above the conveyor support surface, and each said buffs having a buffing surface facing downwardly toward the conveyor support surface for buffing the workpieces while being in sliding contact therewih, said plurality of buffs being arranged in a row across said conveyor and extending transversely of the direction of travel of said conveyor and rotated in one and the same direction, so that said first set of rotary buffs can round the obliquely disposed front and opposite edge portions of said workpiece being conveyed on said conveyor as viewed from the center axes of rotation, and a second set of rotary buffs consisting of a plurality of disk-shaped buffs spaced from said first set in the direction of travel of said conveyor and being of the same diameter which is the same as the diameter of said buffs in said first set and held over said conveyor in a row across said conveyor transversely of the direction of travel thereof, with the center axes of rotation of said buffs in said second set extending vertically above the conveyor surface and each said buff in said second set having a buffing surface facing downwardly toward the conveyor support surface for buffing the workpieces while in sliding contact therewith, the center axes of rotation of said disks in said second set being offset from the center axes of rotation of said buffs in said first set by an amount equal to the radius of each said buff and said buffs in said second set being rotated in the same direction and in the same direction as said buffs in said first set, said buffs in said first set having the circumferential peripheral edges thereof disposed in adjoining relationship and said buffs in said second set having the circumferential peripheral edges thereof disposed in adjoining relationship so that said buffs in each of said first and second sets form a continuous buffing surface transversely across said conveyor, so that said second set of rotary buffs can round the edge portions contrary to said obliquely front and opposite edge portions of said workpiece being conveyed as viewed from said center axes of rotation, whereby sharp corners and burrs on all edge portions of said workpiece can be rounded off.