PROBLEM TO BE SOLVED: To solve such the problems that threshing operation is not stabilized because the conveying speed by a grain culm-feeding and conveying device is changed based on a constantly rotating threshing cylinder, and installing and maintenance operations of a belt, which are carried out frequently, are troublesome because a rotating output shaft to a reaping unit is installed in the inside of a gear case.SOLUTION: The reaping unit 4 is driven while changing the rotating speed by a dedicated stepless speed-changing device 21 for reaping and conveyance so as to synchronize with a traveling speed. The stepless speed-changing device 21 for the reaping and conveyance is equipped with an intermediate output shaft 54 for reaping, installed in a gear case 50 so as to be coaxial with the reaping output shaft 38, an intermediate following gear 56 for the reaping of the intermediate output shaft 39 for the reaping, outputting power to the reaping unit 4, and meshed on one side face of an intermediate output gear 55 for the reaping installed in an intermediate output shaft 54 for the reaping, and an intermediate gear 57 transmitting the rotation to a driving gear 17 for outputting the power to a front-side feeding and conveying device 13, and meshed with the other side face of the intermediate output gear 55 for the reaping.COPYRIGHT: (C)2011,JPO&INPIT【課題】一定回転の扱胴に対して穀稈供給搬送装置の搬送速度が変化するため、脱穀作業が安定しない。刈取部への回転出力軸をギヤケースの内側に設けているから、頻繁に行われるベルトの装着およびメンテナンス作業が面倒である。【解決手段】刈取部4は専用の刈取搬送用無段変速装置21により走行速度に同調して回転速度を変速駆動する。刈取搬送用無段変速装置21は、その刈取出力軸38と同一軸心状に刈取中間出力軸54をギヤケース50内に設け、刈取中間出力軸54に設けた刈取中間出力歯車55の一側面には前記刈取部4に出力する刈取用中間出力軸39の刈取用中間従動歯車56を噛み合わせ、前記刈取中間出力歯車55の他側面には前記前側供給搬送装置13に出力する駆動歯車17へ回転伝達する中間歯車57を噛み合わせる。【選択図】図5
