Dynamics of a planetary needle roller bearing considering the waviness

Abstract

A dynamic model of a planetary needle roller bearing (PNRB) considering the waviness is proposed. This model can formulate the PNRB dynamic motions under high centrifugal acceleration conditions, which are more complicated than those of shaft-fixed bearings. The waviness distributed on the surfaces of races and needle rollers can change the contact conditions between the needle rollers and races. In this study, the effect of the waviness on the roller-race contact forces, roller-cage impact forces, and the PNRB elements’ dynamics are discussed, which were not studied in the listed literature for the PNRB models. Moreover, a case of a PNRB in a single row planetary gear train is used to analyze the relationship between the needle roller-cage impact force and cage speed variation. The effect of the waviness on the vibration characteristics frequency of PNRB races are also studied.

A novel test rig for the investigation of roller-cage impact of a needle roller bearing

“…In this speed range, the speed difference between the roller and the cage is about 6-26 rad s −1 . This speed difference range can be adapted to a wide selection of bearing operating speeds considering cage slip [4,[37][38][39], which is also similar to the operating environment of planetary bearings [20,44].…”