Tsarin injin shine uku roller symmetrical. A saman madaidaiciya a tsakiyar biyu kasa madaidaiciya symmetrical matsayi a tsaye ɗaga motsi, ta hanyar snail, snail samuwa, biyu kasa madaidaiciya a matsayin juyawa motsi, ta hanyar fitarwa kayan aiki na reducer engaged da kasa madaidaiciya kayan aiki, cimma tafiya na farantin. Lokacin da karkashin matsin lamba na saman roller ya wuce iyakar kayan da aka yi amfani da su, yana sa kayan da aka yi amfani da su ya karkatar, tsarin karkatarwa kamar yadda ke ƙasa:

Taswirar da ke sama.