Studies on Frictional Loss and Temperature Rise of Spur Gears : Concentrating on the Use of Mineral Oils and Synthetic Oils

Abstract

Recently, one of the most important problems with gears is in measuring their efficiency and, further, in finding the way to increase it. This problem has already been studied, but the final detailed conclusions have not yet been drawn. In our study, several factors for increasing the efficiency of gears, i.e. factors for decreasing the frictional loss of gears, were investigated. It was found that by means of increasing the viscosity of base oil and concentration of anti-wear and EP additives, we can obtain little effects in the decrement of frictional loss. On the contrary, synthetic oils bring quite remarkable effects in the decrements of frictional loss. Further, the temperature rise in gear teeth was measured in connection with the frictional loss and a relationship was found between them.