Dynamic behavior of a power re-circulating gear test rig including periodic variation of mesh stiffness and static transmission error

2021 ◽  
Vol 159 ◽  
pp. 104247
Author(s):  
M. Abruzzo ◽  
M. Beghini ◽  
C. Santus ◽  
S. Manconi
Keyword(s):  
Dynamic Behavior ◽  
Periodic Variation ◽  
Transmission Error ◽  
Test Rig ◽  
Mesh Stiffness ◽  
Static Transmission Error

Low excitation spur gears with variable tip diameter

2021 ◽  
Vol 263 (5) ◽  
pp. 1275-1285
Author(s):  
Joshua Götz ◽  
Sebastian Sepp ◽  
Michael Otto ◽  
Karsten Stahl
Keyword(s):  
Transmission Error ◽  
Spur Gear ◽  
Low Noise ◽  
Spur Gears ◽  
Mesh Stiffness ◽  
Helical Gears ◽  
Axial Forces ◽  
Tooth Width ◽  
Drive Trains ◽  
Static Transmission Error

One important source of noise in drive trains are transmissions. In numerous applications, it is necessary to use helical instead of spur gear stages due to increased noise requirements. Besides a superior excitation behaviour, helical gears also show additional disadvantageous effects (e.g. axial forces and tilting moments), which have to be taken into account in the design process. Thus, a low noise spur gear stage could simplify design and meet the requirements of modern mechanical drive trains. The authors explore the possibility of combining the low noise properties of helical gears with the advantageous mechanical properties of spur gears by using spur gears with variable tip diameter along the tooth width. This allows the adjustment of the total length of active lines of action at the beginning and end of contact and acts as a mesh stiffness modification. For this reason, several spur gear designs are experimentally investigated and compared with regard to their excitation behaviour. The experiments are performed on a back-to-back test rig and include quasi-static transmission error measurements under load as well as dynamic torsional vibration measurements. The results show a significant improvement of the excitation behaviour for spur gears with variable tip diameter.

scholarly journals Geometry Modification of Helical Gear for Reduction of Static Transmission Error

2018 ◽  
Vol 167 ◽  
pp. 02013
Author(s):  
Jeonghyun Park ◽  
Changjun Seo ◽  
Kwangsuck Boo ◽  
Heungseob Kim
Keyword(s):  
Transmission Error ◽  
Helical Gear ◽  
Necessary Condition ◽  
Mesh Stiffness ◽  
Profile Modification ◽  
Gear Mesh ◽  
Static Transmission Error ◽  
Excitation Mechanisms ◽  
Gear Systems ◽  
Gear Mesh Stiffness

Gear systems are extensively employed in mechanical systems since they allow the transfer of power with a variety of gear ratios. So gears cause the inherent deflections and deformations due to the high pressure which occurs between the meshing teeth when transmit power and results in the transmission error. It is usually assumed that the transmission error and variation of the gear mesh stiffness are the dominant excitation mechanisms. Predicting the static transmission error is a necessary condition to reduce noise radiated from the gear systems. This paper aims to investigate the effect of tooth profile modifications on the transmission error of helical gear. The contact stress analysis was implemented for different roll positions to find out the most critical roll angle in view point of root flank stress. The PPTE (peak-to-peak of transmission error) is estimated at the roll angles by different loading conditions with two dimensional FEM. The optimal profile modification from the root to the tip is proposed.

Numerical and experimental investigation of a spur gear pair with unloaded static transmission error

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Duncai Lei ◽  
Xiannian Kong ◽  
Siyu Chen ◽  
Jinyuan Tang ◽  
Zehua Hu
Keyword(s):  
Transmission Error ◽  
Spur Gear ◽  
Gear Transmission ◽  
Dynamic Responses ◽  
Gear Pair ◽  
Mesh Stiffness ◽  
Content Type ◽  
High Order Harmonic ◽  
Static Transmission Error ◽  
Harmonic Components

Purpose The purpose of this paper is to investigate the dynamic responses of a spur gear pair with unloaded static transmission error (STE) excitation numerically and experimentally and the influences of the system factors including mesh stiffness, error excitation and torque on the dynamic transmission error (DTE). Design/methodology/approach A simple lumped parameters dynamic model of a gear pair considering time-varying mesh stiffness, backlash and unloaded STE excitation is developed. The STE is calculated from the measured tooth profile deviation under the unloaded condition. A four-square gear test rig is designed to measure and analyze the DTE and vibration responses of the gear pair. The dynamic responses of the gear transmission are studied numerically and experimentally. Findings The predicted numerical DTE matches well with the experimental results. When the real unloaded STE excitation without any approximation is used, the dynamic response is dominated by the mesh frequency and its high order harmonic components, which may not be result caused by the assembling error. The sub-harmonic and super-harmonic resonant behaviors are excited because of the high order harmonic components of STE. It will not certainly prevent the separations of mesh teeth when the gear pair is under the condition of high speed and heavy load. Originality/value This study helps to improve the modeling method of the dynamic analysis of spur gear transmission and provide some reference for the understanding of the influence of mesh stiffness, STE excitation and system torque on the vibration behaviors.

Prediction of Automotive Gearboxes Dynamic Behavior: Part A — Experimental Validation of a Global Numerical Model

2000 ◽  
Author(s):  
Karim Yakhou ◽  
Adeline Bourdon ◽  
Daniel Play
Keyword(s):  
Dynamic Behavior ◽  
Experimental Validation ◽  
Numerical Models ◽  
A Priori ◽  
Transmission Error ◽  
Operating Conditions ◽  
Step Procedure ◽  
Validation Procedure ◽  
Static Transmission Error

Abstract Numerical models have been developed to simulate the overall dynamic behavior of automotive gearboxes. They are based upon Finite Element Methods and their main originality is to integrate all the couplings between the various mechanical components of the gearboxes. The purpose of this study is to qualify these numerical models, and then, use them in order to determine gearboxes new design trends. In this first part of two companion papers, an experimental validation procedure has been implemented in two main stages. The first one is devoted to the study of mechanical systems under load but not-rotating. It is organized according to a “step by step” procedure. Starting with the shafts, the other components are gradually mounted and integrated into the mechanical system being considered. Thus, the modeling of the various parts has been validated and the existence of significant couplings has been confirmed. In the second stage of the procedure, the whole gearbox is studied under operating conditions. Preliminary tests at low rotational speeds allow the determination of the quasi-static transmission error under load. The results are used as input data for numerical simulations. Then tests are conducted at higher speeds with various resistant torques. Dynamic transmission error and dynamic loads transmitted by bearings are recorded. A good correlation between experiments and computations ensures the validity of the main a-priori modeling assumptions.

Dynamics of a Truck Gearbox

1992 ◽  
Author(s):  
J. Perret-Liaudet ◽  
J. Sabot
Keyword(s):  
Numerical Simulations ◽  
Dynamic Behaviour ◽  
Equations Of Motion ◽  
Transmission Error ◽  
Gear Transmission ◽  
The Finite Element Method ◽  
Mesh Stiffness ◽  
Gear Mesh ◽  
Static Transmission Error ◽  
Gear Mesh Stiffness

Abstract This work is concerned with numerous numerical simulations of the overall dynamic behaviour of a parallel helical gear transmission. These results are compared to vibratory measurements made with a simplified gearbox test rig. The dynamic modeling of the elastic components of the gear transmission (gears, shafts, bearings, housing) is realized using the finite element method. Fluctuated gear mesh stiffness is introduced owing to stiffness matrix which describes the elastic coupling between the pinion and the wheel. The kinematic transmission error is introduced as a vibratory excitation source. The equations of motion are established in a truncated modal base deduced from the average characteristics of the structure. A new computing method, called “Spectral Method”, is used for analytical study of a simplified gearbox whose housing is a simple rectangular plate. The numerical results allows us to conclude on the dominent phenomenon of the overall dynamic behaviour of the gear transmission. They exhibit in particular the main characteristics of the transfer between the static transmission error and the vibratory response of the gearbox. A series of vibration measurements made on a gearbox close to that used for the numerical simulations, has confirmed this characteristics.

scholarly journals Commentary on effects of tip relief on vibration responses of a geared rotor system

2014 ◽  
Vol 231 (11) ◽  
pp. 2159-2169 ◽  
Author(s):  
Hui Ma ◽  
Xu Pang ◽  
Qibin Wang ◽  
Rongze Song ◽  
Bangchun Wen
Keyword(s):  
Dynamic Model ◽  
Transmission Error ◽  
Original Model ◽  
Rotor System ◽  
Mesh Stiffness ◽  
Coupling Vibration ◽  
Profile Modification ◽  
Torsional Coupling ◽  
Vibration Responses ◽  
Static Transmission Error

The purpose of the present work is to revise the model of Ma et al. ( Proc IMechE, Part C: J Mechanical Engineering Science 2014; 228(7): 1132–1154 ). In that work, emphasis is given to the effects of tip relief on the lateral-torsional coupling vibration responses of the system, in which the time-varying mesh stiffness (TVMS) is calculated without considering the extension of the meshing period of a teeth pair due to dynamic overloads. Moreover, the dynamic model of the geared rotor system does not take into account no-loaded static transmission error (NLSTE) caused by tooth profile modification. In the present paper, the effect of the extended tooth contact on TVMS is considered and the dynamic model of the geared rotor system is revised by introducing the NLSTE. Based on the revised model, TVMS, loaded static transmission error (LSTE), NLSTE, and vibration responses are determined. Finally, comparisons of TVMS, LSTE, and vibration responses between the original model and the revised model are performed. The results show that there are some differences for the vibration responses between the original model and the revised model, and the vibration amplitude of the latter is smaller than that of the former. Furthermore, the conclusion in the original paper that the tip relief is not effective in reducing the vibration at higher mesh frequency range is not consistent with the results in current work any more.

Analysis of Nonlinear Dynamic Accuracy on RV Transmission System

2012 ◽  
Vol 510 ◽  
pp. 529-535 ◽  
Author(s):  
Li Jun Shan ◽  
Yu Ting Liu ◽  
Wei Dong He
Keyword(s):  
Transmission Error ◽  
Transmission System ◽  
Torsional Stiffness ◽  
Mesh Stiffness ◽  
Concentrated Mass ◽  
Input Shaft ◽  
Dynamic Accuracy ◽  
Rv Reducer ◽  
Bearing Stiffness ◽  
Static Transmission Error

RV (Rotate Vector) transmission is a new precision transmission system. In order to improve its accuracy, we study the RV transmission system. It is researched in comprehensive factors including displacement errors, elastic deformation (static transmission error, design transmission error), gear meshing errors, backlash of gear, time-varying mesh stiffness, mesh damping, bearing stiffness, torsional stiffness of input shaft, etc. The mathematical and mechanical model of dynamic transmission accuracy is established by the concentrated mass method and the dynamic substructure method. Then, the meshing force of each part is analyzed in RV reducer. The motion differential equation of RV drive system is obtained, which lays the foundation for the calculation and analysis of the transmission error.

An Experimental Investigation of the Static Transmission Error and Torsional Mesh Stiffness of Nylon Gears

2007 ◽  
Author(s):  
Chuan Wen Chi ◽  
Ian Howard ◽  
Jian De Wang
Keyword(s):  
Experimental Investigation ◽  
Research Work ◽  
Transmission Error ◽  
Statistical Data Analysis ◽  
Mesh Stiffness ◽  
Element Analysis ◽  
Static Transmission Error ◽  
Series Of Experiments ◽  
The Individual ◽  
The Relationship

This paper details an investigation of the relationship between the static individual torsional mesh stiffness and the static transmission error of gears in mesh. The investigations of the individual torsional mesh stiffness are one of the fundamental concepts in gear analysis and behaviour that have been used in recent years for predicting transmission error. The research work for this paper has two main parts. The first part involved measuring the static transmission error of gears through a series of experiments. An existing test rig was used for the experimental investigation where a nylon gear was placed in mesh with a fixed aluminium gear under various torques. Measurements of the rotation of the nylon gear at precise angular positions throughout the mesh cycle were used as a basis for determining the torsional mesh stiffness and the static transmission error. The second part involved the use of numerical analysis tools (FEA) to calculate the theoretical static transmission error and the individual torsional mesh stiffness in the same conditions as the experiments. The validity of the theory of individual torsional mesh stiffness was investigated, through a comparison between the experimental results and the FEA modelling results. The work included experiments, finite element analysis modelling, and statistical data analysis. The final results of this paper showed that individual torsional mesh stiffness theory can effectively predict transmission error in gear transmission systems, however some improvements need to be made to both the theory and the experiments.

Life Estimation of Tilt-Rotor Transmission Based on Dynamic Analysis

2011 ◽  
Vol 86 ◽  
pp. 788-791
Author(s):  
Jia Shun Guo ◽  
San Min Wang ◽  
Hai Xia Liu
Keyword(s):  
Estimation Method ◽  
Transmission Error ◽  
Dynamic Loads ◽  
Mesh Stiffness ◽  
Life Estimation ◽  
Tilt Rotor ◽  
Transmission Design ◽  
Coupling System ◽  
Coupling Dynamic ◽  
Static Transmission Error

Transmission influences on the performance and the security of tilt-rotor directly. A transmission-wing coupling dynamic model including time-varying mesh stiffness and static transmission error was proposed, then calculated the dynamic loads of the transmission-wing coupling system under two flight modes: aircraft and helicopter. Then, computed the life of transmission under different system reliability based on the dynamic loads. This paper presents a more accurate transmission life estimation method. The results present some useful informations for dynamic optimization of the transmission and provide a theoretical basis for the transmission design.

Sign in / Sign up

Export Citation Format

Share Document