Patent ID: 7134622

Claim:
A chipper knife for use in wood chippers having a knife support tool rotatable on an axis of rotation for supporting a plurality of such wood chipper knives in order to cause, during rotation of the tool, chipping of pieces of wood which are fed to the tool, said chipper knife comprising a knife having at least one cutting edge which is formed between a flank and a chip guiding surface, and two opposite main surfaces which are provided on opposite first and second sides of the chipper knife and are adapted to abut against and be retained on opposite seats of a holder mounted on the tool, wherein the first side of the chipper knife is the side that, when the knife is mounted in the holder, will face the wood coming to the chipper, and wherein at least the main surface of the knife located on the first side of the chipper knife has a cross-sectionally permanently curved convex surface portion which connects to and extends backwards from the flank and the chord of which constitutes at least 20% of the total cross-sectional length of the chipper knife.