Effect of the bearing clearance on vibrations of a double-row planetary gear system

Abstract

The bearing clearance, external torque, and input speed can greatly affect vibrations of the planetary gear system. The double-row planetary gear systems are commonly used in the gearbox of special vehicles, which are the key parts to obtain a larger gear ratio. Although many works have been presented to study those factors on vibrations of the single-row planetary gear system, a few works were focused on vibrations of the double-row planetary gear system with the bearing clearance. To overcome this problem, a multi-body dynamic model of a double-row planetary gear system with six planet bearings and one supported bearing of the sun gear is presented. This model is the main part of a gear box transmission system. The new model is developed for studying the effect of the bearing clearance on the planetary system. The meshing stiffness and damping between the gears are obtained by current methods in the listed references, as well as the contact stiffness and damping in bearings. The liner stiffness and damping model is used. The effects of the bearing clearance, external torque, and input speed on vibrations of the system are analyzed. The results show that vibrations of the ring gear and sun gear decrease with the increment of the external torque and increase with the increment of the input speed. Moreover, a reasonable bearing clearance can be helpful for reducing system vibrations for some mating external torque and input speed conditions. The results can provide some guidance to find new method to reduce vibrations and increase the service life of planetary gear systems.

Vibration-Based Diagnostics of Radial Clearances and Bolts Loosening in the Bearing Supports of the Heavy-Duty Gearboxes

“…In other studies [57][58][59][60], theoretical and experimental studies have been conducted for an assessment of modal properties and frequency response functions applicability for detection of structural bolted joint degradation [61]. Some methods of radial clearance diagnostics by vibration signals are given in [62][63][64][65][66][67][68][69][70][71][72][73]. The effect of rolling bearing clearances on diagnostic signatures is investigated in [65] in the 5-DOF nonlinear dynamic model, which imitates gradual wear of bearings, using an experimental identification method based on FRF decoupling and optimization [66].…”

“…Some methods of radial clearance diagnostics by vibration signals are given in [ 62 , 63 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 , 73 ]. The effect of rolling bearing clearances on diagnostic signatures is investigated in [ 65 ] in the 5-DOF nonlinear dynamic model, which imitates gradual wear of bearings, using an experimental identification method based on FRF decoupling and optimization [ 66 ].…”

Analysis of the Dynamic Characteristics of a Gear-Rotor-Bearing System with External Excitation

“…Smagala and Kecik [4] and Kurvinen et al [5] used a two-degree-of-freedom nonlinear bearing model and the Hertz theory to study the effects of the number of balls and the rotational speed of the rotating axle on the dynamic response. Many scholars [6] to [9] have carried out extensive research on bearing failure dynamics and other aspects, and the results provide help for the ontology.…”

Dynamic Model and Response Analysis of Gear-Rotor-Bearing Systems with Bearing Fitting Clearances

“…However, the fitting clearance between the housing and outer ring in bearings is easily caused by unfavorable factors such as manufacturing, assembly, fatigue, wear, and temperature [3,4]. For bearings that rotate at high speeds, collisions and friction between the connecting surfaces are generated due to the fitting clearance, which may cause severe looseness, imbalance, misalignment and other failures [5,6]. Moreover, the vibration of the bearing with fitting clearances is propagated to the gear pair by the rotor, the abnormal meshing of the gear pair is caused, and the degree of system failure may be deepened [7], and the performance and service life will be greatly reduced [8,9].…”