Gearboxes sustain a variety of faults such as broken-shafts, eroded, broken, or missing teeth, and even broken-cases. Casing mounted accelerometers can detect fault patterns but the signals are complicated and difficult to interpret. This study considers the tooth loading of ideal gears and gears with defects. A large industrial gearbox used in a 12m electric mining shovel is modeled. The nonlinear contact mechanics is analyzed to predict the bearing supporting force variation vs. the gear tooth loading after a 3-D CAD model of the gearbox is transferred into multi-body dynamics software. The contact mechanics model of the meshing teeth is built by careful calculation and selection of the contact simulation parameters such as the stiffness, force exponent, and damping and friction coefficients. To simulate the real working environment of the gearbox, simulated bearing support forces are mixed with white noise. The signal is subsequently processed by the Db5 wavelet of the MATLAB Wavelet toolbox. Wavelet analysis results show that bearing supporting force fluctuation cycle is almost the same with that of the meshing forces of the fault gearing pairs, which could be used to predict the tooth malfunction of the gearbox.

/pdf/nonlinear-contact-analysis-of-gear-teeth-for-malfunction-5er3p8gge0.pdf

Nonlinear Contact Analysis of Gear Teeth for Malfunction Diagnostics

To obtain the change tendency of output angular velocity and tangential contact force of a gear when the pinion under the step input during meshing of a new type of spiral bevel gear, which is a logarithmic spiral bevel gear, the tooth flank equation of logarithmic spiral bevel gear is deduced based on the formation mechanism of the tooth flank formation. A three-dimensional model of a pair of logarithmic spiral bevel gears whose number of teeth was 37:9, with modules being 4.5 mm, normal pressure angle being 20 degrees and spiral angle being 35 degrees were built and assembled. Based on Hertz elastic contact theory, the calculation formulas and parameters sets of contact force for conventional spiral bevel gear meshing simulation and logarithmic spiral bevel gear meshing simulation were done. Consider the dynamic simulation about meshing angular velocity and tangential contact force for conventional spiral bevel gear meshing and logarithmic spiral bevel gear meshing, respectively. Finally, by analyzing and comparing the simulation data, the results show that under the same input conditions, the fluctuation of the gear angular velocity and tangential contact force of logarithmic spiral bevel gear meshing are smaller than the conventional spiral bevel gear. That is, the transmission stationary of logarithmic spiral bevel gear meshing is superior to conventional spiral bevel gear.

The meshing angular velocity and tangential contact force simulation for logarithmic spiral bevel gear based on Hertz elastic contact theory

In order to understand the vibration characteristics of gears based on trapped-oil in external spur-gear pump, from the calculations of trapped-oil pressure and hydraulic load and contact stiffness and trapped-oil stiffness, etc., a dynamic model coupled with trapped-oil pressure was derived for the gears, then an iterative operation based on Runge-Kutta method was used for analyzing the model, therefore the data related to trapped-oil pressure and the vibration displacement and the vibration velocity were obtained in a periodic of trapped oil, and the impact of different backlash value and different distance between two unloading grooves on trapped oil pressure and dynamic characteristics of gears was briefly analyzed. All results of simulation showed that trapped-oil pressure and trapped-oil stiffness had greater impact on vibration characteristics of gears in external spur-gear pump, trapped-oil stiffness could reduce the vibration of the gears; in simulation of trapped-oil pressure, dynamic trapped-oil model related to dynamic characteristics of gears more accurate than the static trapped-oil model irrelated to dynamic characteristics of gears; the trapped-oil pressures in two trapped-oil cavity were different, the vibration characteristics of gears was better that in larger backlash value, etc.. Finally, by the trapped-oil stiffness of the external gear pump is unique, the important conclusions are educed that the vibration of gears in external spur-gear pump is indeed different from conventional gears and so on.

Dynamic Model of Gears with Trapped Oil and Coupled Analysis in External Spur-Gear Pump

To solve problems of collaborative modeling & simulation for propulsion device of special ship, a kind of multi-disciplinary simulation platform of virtual prototype based on interface was developed. ADAMS software was as core simulation tool. The analysis flow of collaborative modeling & simulation of virtual prototype was presented for hovercraft. Applied the simulation platform, design course of propulsion device of special ship could be simplified and overall characteristics of propulsion device could be obtained. A propulsion device of propeller and fan driven conjunctly was introduced as special instance.

Virtual Prototype Collaborative Modeling & Simulation Technology for Propulsion Device of Special Ship

In order to obtain the changing pattern of meshing force for broken tooth gear meshing and evaluate quantitatively the battle damage degree of involute gear transmission system, a computation method based on dynamic simulation was proposed. The 3D model of broken gear is established through Pro/E and the dynamic model of involute gear transmission system is established by using the dynamic simulation software ADAMS based on the Hertz contact theory. The model of the gear with different number and position of broken tooth is established when the coincidence degree is known. The simulation results show the meshing force fluctuation frequency and fluctuation amplitude of the gear transmission system show significant differences when the broken tooth number is different or the tooth breaking in different position, and the broken tooth leads the meshing force appears the lag phenomenon.

Dynamic simulation of meshing force in broken tooth involute gear meshing process based on ADAMS

In order to obtain the data of dynamic meshing force of involute gears in meshing transmission process , computer simulation of involute gears meshing transmission simulation is proposed on the basis of MSC-ADAMS software. Considering the high speed and large torque of the gears transmission as well as the variation of meshing point of involute gears in the transmission process, the formula for the calculation of the contact stiffness based on Hertz elastic contact theory was devised and a simulation model was built for the meshing process of involute gears. The meshing process of a pair of gears was simulated in three running situations and their dynamic meshing force responses were calculated. The results showed that the gear meshing forces in the meshing process of involute gears were obviously dynamic. The dynamic loads were not symmetric forces. Moreover, the dynamic forces and their time ratio in a running loop increased with the rise of the rotational velocity of the gears.

Computer Simulation for Dynamic Meshing Force of Involute Gears

Handle everyday research tasks with reliable, citation-backed results

Your personal Research Agent to handle research tasks with citation-backed results

Popular Tasks used by Researchers

How can I help with your research?

Meet SciSpace

Get more enhanced response by uploading the PDFs you want me to reference.

No relevant PDFs in your library

SciSpace is the AI research assistant for academics. Run systematic literature reviews on 280M+ papers, and write papers with cited sources. Trusted by 1M+ students, PhDs & researchers.

SciSpace | AI for Research

Analyze PDFs

Code & Manuscripts

Funding & Grants

Literature & Patents

Medical & Clinical Data

Systematic Review

Visualize & Present

Web & Data

Build a Google Scholar-like website for your research.

Build a website

Create charts and images for your research

Create a Chart

Write a paper for submission to a journal

Draft a manuscript

Patent Search

Design eye-catching scientific posters in minutes.

Scientific Poster Generation

Systematic Literature Review

One task is running at the moment. Your messages will be shown right after.

Drag and drop or click here to browse

Loved by <highlight>1 million+</highlight> researchers

Extract a list of specific topics and their sources from unstructured text

Topics

Compare and analyze relevant papers that matches with your search

Papers

Get insights from PDFs and bookmarked papers from your library

My library

Recent searches

Try searching for:

Catch AI-generated content in scholarly and non-scholarly content

{ai} Detector

Ai Writer

Get PDF Summaries, highlighted text explanations 

Chat with PDF

Effortlessly create in-text citations and bibliographies in APA and 2,500 other formats

Citation generator

Get explanations, summaries, and answers on academic papers

Ease up your research workflow with {scispace}'s cohort of exciting AI tools

Elevate your academic writing skills and convey your ideas the way you want

Paraphraser

Explore our range of reading and writing tools

Your file is being prepared and should be ready in a few minutes. If it's a large file, it might take a bit longer. You can close this window, and we'll email you the file when it's done.

You have reached a maximum limit of <strong>{limit}</strong> columns in the table. Remove at least <strong>1</strong> column to add or create another one.

Liu Ning

Author Tools

Chat about Author

Papers

Computer Simulation for Dynamic Meshing Force of Involute Gears