| The bearing used in aerospace is very sensitive to friction torque. It is notallowed for friction torque to have large fluctuation. But in actual used, the frictiontorque happens to be larger that made the bearing appears sticking phenomenon. Theaerospace environment is very complicated. Some researchers make someexperiments to observe the change law of bearing friction torque in extremetemperature and high vacuum environment. By analysis the test results, theresearchers prove that the extreme temperature and high vacuum can’t make thefriction torque becoming larger than before. As it is impossible to imitatemicrogravity environment, so there is no information to explain how microgravityenvironment influence to the friction torque. Considering all of the reasons, someoneputsforward the sticking theory of ball bearings under extreme conditions.Microgravity can make balls move and stop in self-locking position, and extremetemperature make them generate temperature stress. So the self-locked balls provideadditional friction torque to stop the bearing rotate.Based on the sticking theory, this article will prove it is also applicative to deepgroove ball bearings and enrich the sticking theory.This article will study the sticking criterion of rolling bearings under extremeconditions. By establishment the geometry relationship of bearing, it can determinethe size of self-locking zone in nonload-bearing zone.By using elastic thermodynamicknowledge, it can calculate the temperature stress. It also explore the way to calculatethe friction torque.Compared analysis results with theory results, it can prove it is feasible to usefinite element software simulate bearing movement. Extracting the bearing frictiontorque curves under different working conditions to prove the sticking theory iscorrect.Analysing the feasibility of using finite element software verify the stickingcriterion of rolling bearings under extreme conditions.Through the study of this article, it make the sticking theory more complete thanbefore. By determining the sticking criterion, it provide some informations for designers to calculate the bearing friction torque and choose electrical machineoverload coefficient. It is also significance to improve the quality of aerospacebearings and guarantee the space equipments work normally. |
