RECIPROCATING KNIFE CUTTER WITH FLEXIBLE DRIVE PORTION

摘要

A cutter in which a reciprocating knife is driven by an eccentric mechanism. The knife has a drive portion that flexes laterally in a plane perpendicular to the drive axis of the eccentric mechanism. The eccentric drive axis is offset along the perpendicular plane away from the axis on which the knife reciprocates. The offset of the eccentric drive axis allows the flexible drive portion to be kept straighter during the downstroke than in previous cutters. The increased straightening provides greater columnar strength and reduces deflection and stress of the drive portion during the time the knife is in compression. During the upstroke the knife is bent to a greater degree than in the previous cutters, but during this time the knife is in tension, the tension forces opposing rather than aiding the bending. The offset therefore provides for a longer service life for a blade of equal size or allows a reduction in size and mass of the knife to maintain an equivalent service life.