Lubricating Properties of Tripod Sliding Universal Joints Considering Thermal Effect

Abstract

The tripod sliding universal joint was presented in recent years to transmit torque larger than before. However, its popularization and utilization have encountered numerous obstacles due to premature failures of the main mating surfaces resulting from insufficient lubrication. Therefore, it is important to investigate and improve the lubricating performance thereof. In this work, the effect of the effective radius on the pressure and film thickness as well as the temperature was chiefly discussed under thermal conditions by using the simplified geometric model of the redesigned main mating surfaces. In the meantime, the main results were compared with those obtained under isothermal conditions. The oil film under thermal conditions is thinner than that under isothermal conditions. Thermal effect weakens the second pressure peak. The overall film thickness increases with the increase of the effective radius, whereas the pressure and temperature decrease. The film thickness and temperature increase with increasing entrainment velocity during a stroke. The temperature of the static solid surface is higher than that of the kinetic solid surface.

KEY WORDS:

• Tripod Sliding Universal Joint
• Temperature
• Lubricating Insufficiency
• Film Thickness
• Reciprocating Motion

ACKNOWLEDGEMENTS

The work described in this article was supported by the National Natural Science Foundation of China (Grant No. 50475007). The authors acknowledge the support of Prof. F. Guo, who was helpful in successfully accomplishing this work.

Review led by Gary Barber