Abstract: In this paper,the principle of equilibrating loads in planetary gears is analysed by oil film calculation,and the dynamics characteristics of co-rotating bearing(its bush rotates with journal rotating)are explained by hydrodynamics theory.The analysis results show that the co-rotating bearing has a higher load capability and a larger flexibility of oil film. The Reynolds Equation is solved by numerical method, and results are shown by curves.The experimental in-vestigation on co-rotating beariiig is made,and expcrimental results show that the oil film flexi-bility decreases as the bedring load increases,the flexibility increases as the bearing clearanee in-creases and decreases as bearing rotation rate increases.The experimental investigation on load equilibrating is made in a planetary reducer,and results show that loads among planet gears get agood distribution by using co-rotating bearing.

Key words: tlexibility, gear, journef bearings