Fundamental Research on Gear Lubrication

Abstract

In this paper, the fundamental characteristics of gear lubrication were synthetically clarified, and the oil-film formation between mating gear-teeth was investigated, taking into consideration the dynamic performance of gear-teeth. Using roller and gear testing equipments, the fundamental lubrication characteristics were measured under various driving conditions, and the lubrication characteristic was classified into three regions. The correlation between both lubrication characteristics of rollers and gears was investigated referring to the experimental results, and it is deduced that the analysis of the dynamic phenomena owing to gear mating is very important. The transient characteristics of oil-film due to the gear-mesh were theoretically analyzed, and the transient performance of oil-film was experimentally measured using special models of rollers. The dynamic lubrication theory was applied to the practical gears in consideration of the tooth deflection, and the variation of oil-film thickness was measured through over-all range of a geartooth mesh using a special test gears. From these results, the principle of oil-film formation in gears were discussed.