The present invention relates to an apparatus for adjusting the rotation speed of a combine threshing selection unit. The combine threshing selection unit includes a cutting unit which raises up grains and cuts the grains by a cutting blade, a transport unit which carries the grains to a transport means, a threshing selection unit which threshes and selects the transported grains, a storage unit which stores the threshed and selected grains, and a driving unit which drives a machine body. The rotation force of the main driving shaft (30) driven by the power of an engine (20) of the combine is transferred to a rotation shaft (60) of a threshing drum (50) installed in the threshing selection unit through a driving belt (70). The combine threshing selection unit comprises: a housing (100) which is installed at the end of the outside of the rotation shaft (60) of the threshing drum (50) a driven shaft (200) which is installed in the housing (100) and receives the rotation force from the main driving shaft (30) and an interlocking shaft (300), which is installed between the driven shaft (200) and the rotation shaft (60) in the housing (100) and transfers the rotation force of the main driving shaft (30) to the rotation shaft (60) of the threshing drum (50). The rotation speed of the threshing drum according to the kinds of grains threshed is adjusted rapidly and easily through replacement of a gear transferring power to the rotation shaft of the threshing drum, thereby efficiently performing various grain harvesting work.COPYRIGHT KIPO 2017본 발명은 콤바인 탈곡선별부의 탈곡드럼 회전속도 조절장치에 관한 것으로서, 곡물을 일으켜 세워서 절단날로 베는 예취부와, 곡물을 이송수단으로 운반하는 이송부와, 이송된 곡물을 탈곡하여 선별하는 탈곡선별부와, 탈곡 선별된 곡물을 저장하는 저장부와, 기체를 이동시키는 주행부를 포함하여 구성된 콤바인의 엔진(20) 동력에 의해 구동되는 메인구동축(30)의 회전력이 구동벨트(70)를 통해, 탈곡선별부에 설치된 탈곡드럼(50)의 회전축(60)으로 전달되게 구성하는 콤바인 탈곡선별부에 있어서탈곡드럼(50)의 회전축(60) 외측 단부에 설치하는 하우징(100)과, 하우징(100) 내부에 설치되어 메인구동축(30)에서 회전력을 전달받는 종동축(200)과, 하우징(100) 내부에서 종동축(200)과 회전축(60) 간에 설치되어 메인구동축(30)의 회전력을 탈곡드럼(50)의 회전축(60)으로
