The utility model discloses a hold -in range cutting machine, including the frame, be equipped with cutting device, main gear and overspeed device tensioner in the frame before the follow late arrival in proper order, main gear includes along the driving shaft of controlling the orientation setting that comprise left side initiative axial region and youzhu moving axis portion, and initiative axial region in a left side overlaps the mechanism through the rotation and installs in the frame, be provided with detachable bush mechanism in the youzhu moving axis portion, detachable bush mechanism includes and establishes left position sleeve and right position sleeve in youzhu moving axis portion along the axial spacer sleeve, lie in position department cover between left position sleeve and the right position sleeve in the youzhu moving axis portion and be equipped with the bush, the both ends of bush respectively with left position sleeve and right position sleeve butt, and the position department cover that lies in right position sleeve right side in the youzhu moving axis portion is equipped with lock nut, lock nut with the threaded connection of moving axis portion turns right. The utility model discloses simple structure, low in manufacturing cost easily installs and maintains, convenient to use, safety, reliable.