US Patent 7267146 Chipper bed knife

The invention relates to a chipper (1) bed knife (2) attached detachably to the chipper frame (3), the chipper (1) having a chipper disc (5) supported on its shaft (4), which shaft is fitted rotatably to the chipper frame (3), the chipper disc (5) comprising a number of knives (6) arranged to pass the knife edge (7) of the bed knife (2) at a distance corresponding to the required knife clearance (v), when the chipper disc (5) is rotating. The bed knife (2) also has a second knife edge (7′), the said knife edges (7, 7′) being arranged at a distance from each other in the direction of movement (A) of the chipper disc (5) knives (6). A groove (8) is formed in the bed knife (2) between the said knife edges (7, 7′).