The work presented here provides a mathematical model for solving the problem of lubrication (calculation of efficiency) of worm gear drives, including a description of the engagement geometry and comprehensive modeling of the worm gear drive lubrication process based on the physical characteristics of the lubricant and the applied materials of contact bodies. The established mathematical model is based on the thermo-elasto-hydrodynamic (TEHD) lubrication theory that has proven to be successful in the analysis of journal bearings. The solution of the problem on hand by analyzing the loss of power in gearing, i.e. by analyzing the efficiency ratio of the gear, is basically reduced to the problem of mathematical modeling of local friction coefficients in the oil film along the contact line of the gears. The applicability of TEHD lubrication and the developed computer program were verified by comparing numerical results with experimental values obtained on a test bench using a real worm gear.

U slucajevima mnogih zupcastih parova, ležajeva i kontakata, sile se prenose kroz tanke, kontinualne uljne filmove, koji odvajaju dva elementa u kontaktu. Objekti u kontaktu normalno su izloženi trenju i trosenju, koji mogu biti efektivno reducirani koristenjem maziva. Za kontaktna opterecenja sa malim geometrijskim konformitetom kao sto su zupcanici, kotrljajni ležejevi zbog visokih pritisaka koristi se elasto-hidrodinamicko podmazivanje. U slucaju EHD podmazivanja elasticne deformacije kontaktnih elemenata te porast fluidnog viskoziteta sa pritiskom veoma su znacajni i ne mogu biti ignorisani. Posto deformacije rezultiraju promjenom geometrije uljnog filma koji dalje determinise raspodjelu pritiska, EHD matematicki model mora istovremeno zadovoljiti složene integralne jednacine elasticnosti kao i Reynoldsove diferencijalne jednacine podmazivanja. Ovaj rad daje opis jednacina kod EHD podmazivanja i njihovo rjesavanje primjenom Njutnovog metoda direktnih utjecaja.