Patent ID: 7311279
Filing Date: 2007-12-25
Classification: B02C,Y10S

Abstract:
1. A self sharpening shredding assembly for shredding material introduced into the assembly comprising a first driven cutter having an integral first cutting surface provided on a first shaft for rotation in a first rotary direction, and a second driven cutter having an integral second cutting surface mounted on the second shaft for rotation in an opposite direction to the first cutter where said first and second cutters are located adjacently opposite each other on different shafts so that at least a part of the first cutting surface is in rubbing contact with at least a part of the second cutting surface as the two cutters counter-rotate with respect to each other, said cutters on their respective shafts being urged together to maintain part of the first cutting surface in rubbing contact with a part of the second cutting surface so that material introduced into the cutting assembly between the first and second cutters is cut into smaller pieces by the two cutting surfaces rubbing against one another as the two cutters counter-rotate, said assembly including a cleaning ring mounted on the first shaft adjacent the first cutter and located opposite the second cutter on the second shaft for undergoing an eccentric movement comprising a combination of a first component of movement and a second component of movement wherein rotation of the first cutter imparts the first component of movement to the cleaning ring being a rotary movement and rotation of the second cutter to periodically contact the cleaning ring imparts a second component of movement being essentially a linear movement so that the eccentric movement is a combination of the rotary movement and the linear movement, said cutters being made from a material that is more wear resistant than is the material from which the cleaning ring is made so that as the cleaning ring rubs against the side of the first cutter, the cleaning ring wears in preference to the cutter wearing so that the rubbing movement of the cleaning ring against the cutter keeps the cutter free of debris and maintains the cutting surface in a sharp condition.