scholarly journals Quasi-Static Characteristics and Vibration Responses Analysis of Helical Geared Rotor System with Random Cumulative Pitch Deviations

2020 ◽  
Vol 10 (12) ◽  
pp. 4403
Author(s):  
Bing Yuan ◽  
Geng Liu ◽  
Lan Liu
Keyword(s):  
Degrees Of Freedom ◽  
Transmission Error ◽  
Rotor System ◽  
Dynamic Responses ◽  
Contact Ratio ◽  
Tooth Contact Analysis ◽  
Long Period ◽  
Light Load ◽  
Vibration Responses ◽  
Loaded Tooth Contact Analysis

As one of the long period gear errors, the effects of random cumulative pitch deviations on mesh excitations and vibration responses of a helical geared rotor system (HGRS) are investigated. The long-period mesh stiffness (LPMS), static transmission error (STE), as well as composite mesh error (CMS), and load distributions of helical gears are calculated using an enhanced loaded tooth contact analysis (LTCA) model. A dynamic model with multi degrees of freedom (DOF) is employed to predict the vibration responses of HGRS. Mesh excitations and vibration responses analysis of unmodified HGRS are conducted in consideration of random cumulative pitch deviations. The results indicate that random cumulative pitch deviations have significant effects on mesh excitations and vibration responses of HGRS. The curve shapes of STE and CMS become irregular when the random characteristic of cumulative pitch deviations is considered, and the appearance of partial contact loss in some mesh cycles leads to decreased LPMS when load torque is relatively low. Vibration modulation phenomenon can be observed in dynamic responses of HGRS. In relatively light load conditions, the amplitudes of sideband frequencies become larger than that of mesh frequency and its harmonics (MFIHs) because of relatively high contact ratio. The influences of random cumulative pitch deviations on the vibration responses of modified HGRS are also discussed.

Torque Load Effects on Mesh and Dynamic Characteristics of Hypoid Geared System

2013 ◽  
Author(s):  
Yawen Wang ◽  
Teik C. Lim ◽  
Junyi Yang
Keyword(s):  
Dynamic Characteristics ◽  
Gear Tooth ◽  
Great Influence ◽  
Transmission Error ◽  
Hypoid Gear ◽  
Contact Ratio ◽  
Mesh Stiffness ◽  
Tooth Contact Analysis ◽  
Torque Load ◽  
Loaded Tooth Contact Analysis

From the existing experimental results and previous studies, the torque load has great influence on the mesh and dynamic characteristics of hypoid gear drive. To have more insights on the load dependent mesh parameters and dynamic response of hypoid and spiral bevel gear, a load dependent mesh model is developed by using 3-dimensional loaded tooth contact analysis (LTCA). The contact ratio and time-varying mesh parameters including the mesh stiffness, transmission error, mesh point and line-of-action of the mesh force are examined within a wide torque range. Then a nonlinear multi-body dynamic analysis is performed considering the effect of backlash nonlinearity. Simulation results show that the contact ratio and mesh stiffness generally increases as the toque load increases. The effect of torque load on dynamic mesh force is found to be frequency dependent due to the resonance frequency shifts and peak magnitude changes. This study provides an in-depth understanding of hypoid gear tooth load sharing and dynamic behaviors in terms of change in operating load. Therefore, the proposed model can be employed to assist in gear design optimization.

Measurements and theoretical analysis of a helical gear meshing impact signal

2019 ◽  
Vol 233 (4) ◽  
pp. 827-839
Author(s):  
Shengyang Hu ◽  
Zongde Fang ◽  
Chao Liu ◽  
Long Xiang
Keyword(s):  
Relevant Literature ◽  
Transmission Error ◽  
Contact Analysis ◽  
Practical Significance ◽  
Single Pair ◽  
Contact Ratio ◽  
Tooth Contact Analysis ◽  
Tooth Contact ◽  
Maximum Deformation ◽  
Loaded Tooth Contact Analysis

Meshing impact is an important factor that affects gear vibration and noise. Therefore, it is of great theoretical and practical significance to study the characteristics of offline meshing impact to reduce the vibration caused by meshing impact. Currently, a single-pair gear is the research goal, ignoring complex coupling relationships between systems, and the established numerical solution formula of the meshing impact cannot be verified. By using Hilbert demodulation and instantaneous frequency, this study obtained the meshing impact signal from the dynamic transmission error signal of the experiment and obtained the maximum deformation caused by the meshing impact. The meshing stiffness of a single tooth was obtained by loaded tooth contact analysis and tooth contact analysis, and the meshing impact force was calculated. The dynamic model of the meshing impact considering the contact ratio was established to compare with the obtained force in the experiment. The method of measuring the meshing impact signal from experiments has not been reported in relevant literature. The method has the advantages of being extensive, accurate and convenient, and it is not affected by the complexity of the system. At the same time, this method can be used to determine the gear teeth with meshing impact in the course of operation and provide a basis for real-time shape modification and design. Therefore, it is of great significance.

Simulation and Experimental Measurement of the Transmission Error of Real Hypoid Gears Under Load

2000 ◽  
Vol 122 (1) ◽  
pp. 109-122 ◽  
Author(s):  
Claude Gosselin ◽  
Thierry Guertin ◽  
Didier Remond ◽  
Yves Jean
Keyword(s):  
Measurement Data ◽  
Simulation Models ◽  
Transmission Error ◽  
Contact Analysis ◽  
Hypoid Gear ◽  
Tooth Contact Analysis ◽  
Tooth Contact ◽  
Hypoid Gears ◽  
Loaded Tooth Contact Analysis ◽  
Analysis Models

The Transmission Error and Bearing Pattern of a gear set are fundamental aspects of its meshing behavior. To assess the validity of gear simulation models, the Transmission Error and Bearing Pattern of a Formate Hypoid gear set are measured under a variety of operating positions and applied loads. Measurement data are compared to simulation results of Tooth Contact Analysis and Loaded Tooth Contact Analysis models, and show excellent agreement for the considered test gear set. [S1050-0472(00)00901-6]

Optimal Machine-Tool Settings for the Manufacture of Face-Hobbed Spiral Bevel Gears

2014 ◽  
Vol 136 (8) ◽  
Author(s):  
Vilmos V. Simon
Keyword(s):  
Contact Pressure ◽  
Optimization Problem ◽  
Transmission Error ◽  
Search Method ◽  
Tooth Contact Analysis ◽  
Tooth Contact ◽  
Transmission Errors ◽  
Bevel Gears ◽  
Spiral Bevel ◽  
Loaded Tooth Contact Analysis

In this study, an optimization methodology is proposed to systematically define the optimal head-cutter geometry and machine-tool settings to simultaneously minimize the tooth contact pressure and angular displacement error of the driven gear (the transmission error), and to reduce the sensitivity of face-hobbed spiral bevel gears to the misalignments. The proposed optimization procedure relies heavily on the loaded tooth contact analysis for the prediction of tooth contact pressure distribution and transmission errors influenced by the misalignments inherent in the gear pair. The load distribution and transmission error calculation method employed in this study were developed by the author of this paper. The targeted optimization problem is a nonlinear constrained optimization problem, belonging to the framework of nonlinear programming. In addition, the objective function and the constraints are not available analytically, but they are computable, i.e., they exist numerically through the loaded tooth contact analysis. For these reasons, a nonderivative method is selected to solve this particular optimization problem. That is the reason that the core algorithm of the proposed nonlinear programming procedure is based on a direct search method. The Hooke and Jeeves pattern search method is applied. The effectiveness of this optimization was demonstrated on a face-hobbed spiral bevel gear example. Drastic reductions in the maximum tooth contact pressure (62%) and in the transmission errors (70%) were obtained.

Simulation Analysis of Contact Pattern and Strength of WN Gears Having Tooth Surface Deviations

2012 ◽  
Vol 479-481 ◽  
pp. 944-948 ◽  
Author(s):  
Dian Hua Chen ◽  
Zhong Wei Zhang
Keyword(s):  
Simulation Analysis ◽  
Practical Method ◽  
Transmission Error ◽  
Tooth Surface ◽  
Contact Pattern ◽  
The Finite Element Method ◽  
Tooth Contact Analysis ◽  
Surface Deviations ◽  
Tooth Surfaces ◽  
Loaded Tooth Contact Analysis

A practical method based on normal gaps topography is proposed here for loaded tooth contact analysis of WN gear having tooth surface deviations. The simulation of meshing state and tooth strength of WN gear are provided with real tooth surfaces. In the study normal gaps distribution is adopted to calculate tooth surface contact elastic deformation and local deviations due to manufacturing errors and tooth surface wear. For WN gear, the loaded distribution on the contact zone in meshing tooth surface has not been investigated because of their complexity in the contact state. The finite element method is adopted to analyze the contact pattern and tooth strength. The study has concretely calculated the contact pressure and zone of meshing in different loaded and transmission error. At the end examples are analyzed to demonstrate the effectiveness of the proposed method in quantifying effect of such deviations on the loaded distribution and tooth stress distribution.

Stability and Bifurcation of Nonlinear Bearing-Flexible Rotor System with a Single Disk

2010 ◽  
Vol 148-149 ◽  
pp. 141-146
Author(s):  
Di Hei ◽  
Yong Fang Zhang ◽  
Mei Ru Zheng ◽  
Liang Jia ◽  
Yan Jun Lu
Keyword(s):  
Nonlinear Dynamic ◽  
Degrees Of Freedom ◽  
Rotor System ◽  
Dynamic Responses ◽  
Flexible Rotor ◽  
Runge Kutta Method ◽  
Stability And Bifurcation ◽  
Single Disk ◽  
The Stability ◽  
Predictor Corrector

Dynamic model and equation of a nonlinear flexible rotor-bearing system are established based on rotor dynamics. A local iteration method consisting of improved Wilson-θ method, predictor-corrector mechanism and Newton-Raphson method is proposed to calculate nonlinear dynamic responses. By the proposed method, the iterations are only executed on nonlinear degrees of freedom. The proposed method has higher efficiency than Runge-Kutta method, so the proposed method improves calculation efficiency and saves computing cost greatly. Taking the system parameter ‘s’ of flexible rotor as the control parameter, nonlinear dynamic responses of rotor system are obtained by the proposed method. The stability and bifurcation type of periodic responses are determined by Floquet theory and a Poincaré map. The numerical results reveal periodic, quasi-periodic, period-5, jump solutions of rich and complex nonlinear behaviors of the system.

Dynamics of Hypoid Gear Transmission With Nonlinear Time-Varying Mesh Characteristics

2003 ◽  
Vol 125 (2) ◽  
pp. 373-382 ◽  
Author(s):  
Yuping Cheng ◽  
Teik C. Lim
Keyword(s):  
Response Spectra ◽  
Transmission Error ◽  
Operating Conditions ◽  
Time Varying ◽  
Analysis Model ◽  
Tooth Contact Analysis ◽  
3 Dimensional ◽  
Resonant Modes ◽  
Loaded Tooth Contact Analysis ◽  
Backlash Nonlinearity

The coupled translation-rotation vibratory response of hypoid geared rotor system due to loaded transmission error excitation is studied by employing a generalized 3-dimensional dynamic model. The formulation includes the effects of backlash nonlinearity as well as time-dependent mesh position and line-of-action vectors. Its mesh coupling is derived from a quasi-static, 3-dimensional, loaded tooth contact analysis model that accounts for the precise gear geometry and profile modifications. The numerical simulations show significant tooth separation and occurrence of multi-jump phenomenon in the predicted response spectra under certain lightly loaded operating conditions. Also, resonant modes contributing to the response spectra are identified, and cases with super-harmonics are illustrated. The computational results are then analyzed to quantify the extent of non-linear and time-varying factors.

Modeling of Helical Gear Power Tri-Branching Transmission Based on Loaded Tooth Contact Analysis

2013 ◽  
Vol 372 ◽  
pp. 543-546
Author(s):  
Xiao Fang Yang ◽  
Zong De Fang ◽  
Yong Zhen Zhang ◽  
Yuan Fei Han
Keyword(s):  
Structural Model ◽  
Transmission Error ◽  
Helical Gear ◽  
Transmission System ◽  
Contact Analysis ◽  
Tooth Contact Analysis ◽  
Tooth Contact ◽  
Actual Application ◽  
Loaded Tooth Contact Analysis ◽  
Numerical Precision

According to the principle of tri-branching, a mechanism structural model was developed to analyze the helical gear transmission system. On the base of loaded tooth contact analysis (LTCA), the load transmission error of each gear stage is simulated at the any engagement position, and the fitting curves of the torsion mesh stiffness are obtained, which can improve the numerical precision. The research results can be applied to analyze the actual application of tri-branching transmission system and provide a firm foundation for study the power-split and load-sharing characteristics.

Eccentricity Effect Analysis in Right-Angle Gear Dynamics

2011 ◽  
Author(s):  
Tao Peng ◽  
Teik C. Lim ◽  
Junyi Yang
Keyword(s):  
High Speed ◽  
Low Frequency ◽  
Transmission Error ◽  
Dynamic Responses ◽  
Computational Time ◽  
Model Parameters ◽  
Tooth Contact Analysis ◽  
Effect Analysis ◽  
Tolerance Specification ◽  
Assembly Error

Geometric eccentricity here refers to the radial deviation (radial runout) of pinion or gear geometric center off its rotational center or axis. Such a typical manufacturing or assembly error in gear transmission exhibits inherent effects on the gear dynamic responses. Modeling of eccentricity has rarely been done for high speed right-angle gears such as hypoid or spiral bevel gears. In this paper, two modeling methods are proposed to quantitatively represent the eccentricity in the hypoid/bevel gear dynamic analysis. The first method is based on the loaded tooth contact analysis (LTCA) for a long shaft period. The LTCA results are then used to synthesize the corresponding roll angle dependent varying mesh model parameters. A second simpler method using translational kinematic transmission error (TE) modification is proposed to reduce the computational time. The effects of eccentricity on the gear dynamic responses are then investigated. The eccentricity excited low frequency shaft order dynamics is found to affect not only the overall level of vibration but also the high frequency mesh order responses. The sideband responses are simulated and characterized. This study is expected to improve the right-angle gearing system dynamic analytical capability and assist in guiding the manufacturing or assembly error tolerance specification.

Loaded Tooth Contact Analysis of Face Gear Drive with Modification

2010 ◽  
Vol 29-32 ◽  
pp. 1711-1716
Author(s):  
Shu Yan Zhang ◽  
Hui Guo
Keyword(s):  
Transmission Error ◽  
Contact Analysis ◽  
Tooth Surface ◽  
Face Gear ◽  
Tooth Contact Analysis ◽  
Tooth Contact ◽  
Gear Drive ◽  
Bearing Contact ◽  
Tooth Number ◽  
Loaded Tooth Contact Analysis

A double direction modification with a grinding worm is applied on tooth surface of face gear drive. The surface equations of the rack cutter, shaper and grinding worm are derived respectively. Loaded tooth contact analysis (LTCA) with finite element method (FEM) is performed to investigate the meshing performance of face gear drive before modification and after modification. The modification by a grinding worm can obviously reduce the sensitivity of face gear drive to misalignment; the bending stress and the contact stress are reduced with avoiding edge contact; the load transmission error is reduced. This method can obtain a more stable bearing contact in contrast to the method by increasing tooth number of shaper, and the modification magnitude can be controlled freely. The investigation is illustrated with numerical examples.

Sign in / Sign up

Export Citation Format

Share Document