PROBLEM TO BE SOLVED: To hardly have an adverse effect on a screw drive shaft even if a large load acts on a chopper drive shaft and rotation unevenness occurs.SOLUTION: A combine harvester includes a belt transmission mechanism for transmitting torque from an output shaft 51 to grain discharging screw drive shafts 59 and 61 of a thresher 3 and a chopper drive shaft 69 of a chopper 66 for finely cutting straw wastes discharged from the end of a threshing chamber through a drive belt. A first belt transmission mechanism 78 ranging from the output shaft 51 to the screw drive shafts 59 and 61 and a second belt transmission mechanism 80 ranging from the output shaft 51 to the chopper drive shaft 69 are individually arranged as the belt transmission mechanism.COPYRIGHT: (C)2013,JPO&INPIT【課題】チョッパ駆動軸に大きな負荷が作用して回転ムラを生じても、スクリュ駆動軸に悪影響を与え難くする。【解決手段】出力軸51から、脱穀装置3の穀粒排出用のスクリュ駆動軸59,61、及び、扱室の終端から排出されたワラ屑類を細断するチョッパ66のチョッパ駆動軸69に駆動ベルトを介して回転力を伝達するベルト伝動機構を備えたコンバインであって、ベルト伝動機構として、出力軸51とスクリュ駆動軸59,61とに亘る第1ベルト伝動機構78と、出力軸51とチョッパ駆動軸69とに亘る第2ベルト伝動機構80とを個別に設けてある。【選択図】図3