PROBLEM TO BE SOLVED: To solve a problem that conventionally, a high-speed cutter shaft and a low-speed cutter shaft having rotary blades and a transportation shaft having a spiral are arranged in parallel in a waste straw cutter so that the waste straw cutter has a limitation in compacting.SOLUTION: In this waste straw cutter in which the high-speed cutter shaft 11 and the low-speed cutter shaft 12 are arranged in parallel, a plenty of high- speed rotary blades 21 are fixed to the high-speed cutter shaft, a plenty of low-speed rotary blades 13 are fixed to the low-speed cutter shaft, waste straws are thrown between the opposing high-speed rotary blades and low-speed rotary blades and cut, the spiral 23 is arranged on at least one cutter shaft and a gap between the rotary blades in the direction of the cutter shaft is much narrowed in the downstream side than in the upstream side in the transportation direction by the spiral.COPYRIGHT: (C)2002,JPO【課題】 従来、排藁切断装置には回転刃を有する高速カッター軸と低速カッター軸と、スパイラを有する搬送軸が平行に配置され、排藁切断装置をコンパクト化するには限界があった。【解決手段】 高速カッター軸11と低速カッター軸12を平行に配置し、該高速カッター軸上に複数の高速回転刃21・21・・・を固定し、低速カッター軸上に複数の低速回転13・13・・・を固定して、対向する高速回転刃と低速回転刃の間に排藁を投入して切断する排藁切断装置において、少なくとも一方のカッター軸上にスパイラ23を設け、前記カッター軸方向の回転刃と回転刃の間隔を、スパイラによる搬送方向上流側よりも下流側を狭くした。
