Uhlelo lwesikhathi luyingxenye ebalulekile yesitimela se-valve yenjini futhi enye yezinto ezibalulekile zokuqinisekisa ukuphefumula kahle kwenjini.

Umsebenzi we-sprocket yesikhathi ulingana nebhande lesikhathi. Iyingxenye ebalulekile yesistimu yokusabalalisa igesi yenjini. Ixhunywe ku-crankshaft futhi isebenzisana nesilinganiso esithile sokudlulisela ukuqinisekisa ukunemba kwesikhathi sokuthatha kanye nokukhipha.

Indima ye-sprocket yesikhathi yukuthi lapho injini isebenza, ukushaywa kwe-piston (ukunyakaza phezulu naphansi) ukuvula nokuvalwa kwe-valve (isikhathi) ukulandelana kokushisa (isikhathi), ngaphansi kokuxhumeka kwe "isikhathi", hlala njalo "uvumelanisiwe" " Gijima.

Ngesikhathi sokusebenza kwenjini yemoto, izinqubo ezine zokungenisa, ukucindezelwa, ukuqhuma, nokukhipha umoya ziyenzeka ngokuqhubekayo kusilinda, futhi isikhathi sesinyathelo ngasinye kufanele sihambisane nesimo sokunyakaza kanye nendawo yepiston, ukuze ukungenisa. kanye nama-exhaust Piston lifts ahlanganiswa nomunye nomunye, futhi ama-sprockets esikhathi adlala indima "njengebhuloho" enjinini, edlulisela amandla ezingxenyeni ezihambisanayo ngaphansi ukushayela kwe-crankshaft.