Imashini yimashini ya rotary ni igice cyingenzi cyimashini zikoreshwa mubuhinzi mugukata no gutema.Intego ya garebox ni ugukwirakwiza ingufu zituruka ku mashanyarazi ya traktori (PTO) ku cyuma kizunguruka cyo gutema no guca ibyatsi, ibihingwa cyangwa ibindi bimera.Gearbox ikora neza ningirakamaro kuko ituma ibyuma byimashini bizunguruka ku muvuduko mwinshi kugirango bigabanye vuba kandi bitemye ibimera byuzuye.Gearbox ubwayo ikozwe mubyuma cyangwa aluminium.Igizwe nibice byinshi byingenzi nko kwinjiza no gusohora ibiti, ibikoresho, ibyuma, hamwe na kashe.Shaft yinjiza ihujwe na traktor ya PTO ishinzwe kubyara ingufu zizunguruka.