Mitundu ya zidareducer worm gear reducer ndi njira yotumizira mphamvu yomwe imagwiritsa ntchito chosinthira liwiro la giya kuti ichepetse kuchuluka kwa zosinthika zamagalimoto mpaka pakufunika kosinthira ndikupeza makina akulu a torque. M'makina omwe amagwiritsidwa ntchito popereka mphamvu ndi kuyenda, kuchuluka kwa zochepetsera ndikokwanira. Zotsatira zake zitha kuwoneka pamakina otumizira amitundu yonse yamakina kuchokera ku zombo zamagalimoto zamagalimoto zamagalimoto olemera makina omanga, makina opangira makina ndi zida zopangira zokha zomwe zimagwiritsidwa ntchito pamakina opangira makina kupita ku zida wamba zapakhomo pawotchi ya tsiku ndi tsiku etc. Kugwiritsa ntchito chochepetsera kumatha kuwoneka kuchokera pakupatsira mphamvu yayikulu kupita kumayendedwe ang'onoang'ono ndi ngodya yolondola. M'mafakitale, chochepetsera chimakhala ndi ntchito zochepetsera komanso kuwonjezeka kwa torque. Chifukwa chake, imagwiritsidwa ntchito kwambiri pazida zosinthira liwiro komanso torque.
Kuti apititse patsogolo magwiridwe antchito azida za nyongolotsi zochepetsera, zitsulo zopanda chitsulo nthawi zambiri zimagwiritsidwa ntchito ngati zida za nyongolotsi ndi chitsulo cholimba ngati tsinde la nyongolotsi. Chifukwa ndi sliding friction drive, panthawi yogwira ntchito, imapanga kutentha kwakukulu, komwe kumapangitsa mbali za kuchepetsa ndi kusindikiza. Pali kusiyana kwa kutentha kwapakati pakati pawo, zomwe zimapangitsa kusiyana pakati pa mating aliwonse, ndipo mafuta amakhala ochepa kwambiri chifukwa cha kuwonjezeka kwa kutentha, zomwe zimakhala zosavuta kuyambitsa. Pali zifukwa zinayi zazikuluzikulu, chimodzi ndi chakuti ngati kufananiza kwa zinthu kuli koyenera, chinacho ndi mawonekedwe a pamwamba pa mikangano ya meshing, chachitatu ndi kusankha mafuta opaka mafuta, ngati kuchuluka kwa kuonjezera kuli kolondola, ndipo chachinayi ndi khalidwe la msonkhano ndi malo ogwiritsira ntchito.