Free vibration characteristics of compound planetary gear train sets

In this study, a plane model of a compound planetary gear train (CPGT) is proposed in order to study its free vibration characteristics. Two translations and one rotation are considered for each element (sun, carrier, ring-1, ring-2, and planets) of the CPGT. The contact between the teeth in mesh is modelled by linear springs with stiffness called gearmesh stiffness. The phasing between these stiffness is taken into account. Using Lagrange formulation, the equation of motion is derived. Starting from the eigenvalue problem of the system, the influence of the planets’ number and position, and the effect of the gyroscopic phenomena on the free vibration of the CPGT are studied. The natural modes are classified into three groups: translational (the carrier, ring 1, and sun have pure modal translational deflection with no rotation), rotational (the carrier, ring 1, and sun have pure modal rotational deflection with no translation), and planets’ modes (only the planets have a modal deflection). It was found that the change of the planets’ angular position does not affect this classification. On the other hand, the study of the influence of the carrier rotation speed show that the gyroscopic effect separates the repeated translational modes into distinct ones. The obtained results are much important in the design process in order to avoid critical operating conditions which lead to undesirable vibrations.

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Dynamic Analysis of Helical Planetary Gear Train

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.404.312 ◽

2013 ◽

Vol 404 ◽

pp. 312-317 ◽

Cited By ~ 1

Author(s):

Xian Zeng Liu ◽

Jun Zhang

Keyword(s):

Steady State ◽

Free Vibration ◽

Dynamic Model ◽

Planetary Gear ◽

Gear Train ◽

Dynamic Responses ◽

Design Parameters ◽

Planetary Gear Train ◽

State Dynamic ◽

The Impact

A dynamic model for helical planetary gear train (HPGT) is proposed. Based on the model, the free vibration characteristics, steady-state dynamic responses and effects of design parameters on system dynamics are investigated through numerical simulations. The free vibration of the HGPT is classified into 3 categories. The classified vibration modes are demonstrated as axial translational and torsional mode (AT mode), radial translational and rotational mode (RR mode) and planet mode (P mode) followed by the characteristics of each category. The simulation results agree well with those of previous discrete model when neglecting the component flexibilities, which validates the correctness of the present dynamic model. The steady-state dynamic responses indicate that the dynamic meshing forces fluctuate about the average static values and the time-varying meshing stiffness is one of the major excitations of the system. The parametric sensitivity analysis shows that the impact of the central component bearing stiffness on the dynamic characteristic of the HPGT system is significant.

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Dynamic modeling and vibration characteristics of a two-stage closed-form planetary gear train

Mechanism and Machine Theory ◽

10.1016/j.mechmachtheory.2015.10.006 ◽

2016 ◽

Vol 97 ◽

pp. 12-28 ◽

Cited By ~ 29

Author(s):

Lina Zhang ◽

Yong Wang ◽

Kai Wu ◽

Ruoyu Sheng ◽

Qilin Huang

Keyword(s):

Closed Form ◽

Dynamic Modeling ◽

Planetary Gear ◽

Vibration Characteristics ◽

Gear Train ◽

Two Stage ◽

Planetary Gear Train

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Vibration Characteristics of Friction Plate of a 6-Speed Planetary Gear Train Base on Multi-Body Dynamic Model

Volume 10: 2017 ASME International Power Transmission and Gearing Conference ◽

10.1115/detc2017-67045 ◽

2017 ◽

Author(s):

Tinghui Su ◽

Zheng Cao ◽

Yimin Shao ◽

Liming Wang ◽

Hongwu Li ◽

...

Keyword(s):

Dynamic Model ◽

Impact Damage ◽

Planetary Gear ◽

Vibration Characteristics ◽

Gear Train ◽

Planetary Gear Train ◽

Operation Conditions ◽

Friction Plate ◽

Multi Body ◽

The Impact

As braking components, friction plates are key components in automobile transmissions. Due to tough working conditions, i.e. high speed, high friction, fracture and plastic deformation are easily observed in friction plates. However, most of previous studies mainly focused on the chemical analysis of the fracture friction plate, the researches on impact damage have rarely published in the listed literature. In order to investigate the impact damage for friction plate, a dynamic model for a friction plate of a 6-speed planetary gear train is established based on multi-body theory. The dynamic model of planetary gear transmission mechanism is constructed. The rotating speed of the inner hub is obtained. Furthermore, the contact force between the friction plate and the inner hub is calculated. The relationship between the vibration characteristics of the friction plate and operation conditions are studied.

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Dynamic Characteristics of Double Helical Planetary Gear Train With Tooth Friction

Volume 10: ASME 2015 Power Transmission and Gearing Conference; 23rd Reliability, Stress Analysis, and Failure Prevention Conference ◽

10.1115/detc2015-48022 ◽

2015 ◽

Cited By ~ 1

Author(s):

Fengxia Lu ◽

Rupeng Zhu ◽

Haofei Wang ◽

Heyun Bao ◽

Miaomiao Li

Keyword(s):

Degrees Of Freedom ◽

Sliding Friction ◽

Planetary Gear ◽

Gear Train ◽

Variable Step Size ◽

Step Size ◽

Planetary Gear Train ◽

Gear Mesh ◽

Meshing Stiffness ◽

Nonlinear Dynamics Model

A new nonlinear dynamics model of the double helical planetary gear train with 44 degrees of freedom is developed, and the coupling effects of the sliding friction, time-varying meshing stiffness, gear backlashes, axial stagger as well as gear mesh errors, are taken into consideration. The solution of the differential governing equation of motion is solved by variable step-size Runge-Kutta numerical integration method. The influence of tooth friction on the periodic vibration and nonlinear vibration are investigated. The results show that tooth friction makes the system motion become stable by the effects of the periodic attractor under the specific meshing frequency and leads to the frequency delay for the bifurcation behavior and jump phenomenon in the system.

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