PROBLEM TO BE SOLVED: To provide a straw-cutting blade having an improved strength at the base end side of a blade plate part to elongate the endurance life.SOLUTION: The straw-cutting blade is constituted as follows: each valley part 6 of uneven blade edges 7 present within a prescribed range from the base end part of the blade plate part 4 is formed into an chamfered valley part 6B in which the valley bottom part is in an chamfer without being formed into a pointed valley part 6A in a V-shaped groove shape. Each of the chamfered valley part 6B is formed into a shape regulated so that the chamfer at the valley part present nearer the protrusion end side of the blade part 4 may be smaller, and so that the chamfered valley part 6B at a position nearer to the protrusion end side of the blade plate part 4 may gradually approach the pointed shape.COPYRIGHT: (C)2011,JPO&INPIT【課題】刃板部の基端部側の強度が向上して耐久寿命が長期化するわら切刃を提供すること。【解決手段】刃板部4の基端部から所定範囲に存する凹凸刃縁7の各谷部6を、V字溝形状の先鋭谷部6Aとせずに谷底部がR形状となるR形状谷部6Bに形成すると共に、この各R形状谷部6Bは、刃板部4の突出先端側に位置するものほど谷底部のR形状が小さくなる形状に形成して、刃板部4の突出先端側に位置するR形状谷部6Bほど徐々に先鋭形状に近づくように構成したわら切刃。【選択図】図1
