Simulation and experimental study of influences of shape of roller on the lubrication performance of precision speed reducer

This paper presents a study to investigate the effects of the shape of rollers in high precision enveloping speed reducer on the reducer's lubrication performance. Theoretical models for the precision speed reducer with cylindrical and conical rollers as its transmission components were constructed at first based on the meshing theory. Next, numerical analysis was conducted investigate the lubrication status of the speed reducers with different types of rollers at four rotation speeds using ParticleWorks. The moving particle semi-implicit method embedded in that software was used to model the reducers and the inside lubricant flow. A sequence of tests was performed to inspect the transmission efficiency of the reducers at four different rotation speeds. Experimental data were compared to the simulation predictions. Comparisons showed that the data measured from the experiments matched the simulation results very well. Both experimental and computational results confirmed that the lubrication performance of the enveloping speed reducer with conical rollers is better than that of the speed reducer with cylindrical rollers. It has also been proven that the method of using the churning power losses to assess the effects of the shape of the rollers on the roller enveloping speed reducer's lubrication behavior is highly reliable.