Reductions of Bending Stresses and Wear in an Aerodynamic Involute Spur Gear Profile

2020 ◽  
pp. 319-327
Author(s):  
Y. P. Ravitej ◽  
O. Abhilash ◽  
Naveen kumar
Keyword(s):  
Spur Gear ◽  
Bending Stresses ◽  
Gear Profile

Modeling of surface roughness in a novel magnetorheological gear profile finishing process

2020 ◽  
pp. 095440622097826
Author(s):  
Ravi Datt Yadav ◽  
Anant Kumar Singh ◽  
Kunal Arora
Keyword(s):  
Surface Roughness ◽  
Gear Tooth ◽  
Surface Characteristics ◽  
Spur Gear ◽  
Tooth Profile ◽  
Tooth Surface ◽  
Magnetic Flux Density ◽  
Element Analysis ◽  
Finishing Process ◽  
Gear Profile

Fine finishing of spur gears reduces the vibrations and noise and upsurges the service life of two mating gears. A new magnetorheological gear profile finishing (MRGPF) process is utilized for the fine finishing of spur gear teeth profile surfaces. In the present study, the development of a theoretical mathematical model for the prediction of change in surface roughness during the MRGPF process is done. The present MRGPF is a controllable process with the magnitude of the magnetic field, therefore, the effect of magnetic flux density (MFD) on the gear tooth profile has been analyzed using an analytical approach. Theoretically calculated MFD is validated experimentally and with the finite element analysis. To understand the finishing process mechanism, the different forces acting on the gear surface has been investigated. For the validation of the present roughness model, three sets of finishing cycle experimentations have been performed on the spur gear profile by the MRGPF process. The surface roughness of the spur gear tooth surface after experimentation was measured using Mitutoyo SJ-400 surftest and is equated with the values of theoretically calculated surface roughness. The results show the close agreement which ranges from −7.69% to 2.85% for the same number of finishing cycles. To study the surface characteristics of the finished spur gear tooth profile surface, scanning electron microscopy is used. The present developed theoretical model for surface roughness during the MRGPF process predicts the finishing performance with cycle time, improvement in the surface quality, and functional application of the gears.

Bending Strength of Carburized Forged Spur Gear

2007 ◽  
Author(s):  
Masashi Yamanaka ◽  
Shinji Miwa ◽  
Katsumi Inoue ◽  
Yoshiki Kawasaki
Keyword(s):  
Fatigue Strength ◽  
Fatigue Test ◽  
Bending Strength ◽  
Surface Hardness ◽  
Spur Gear ◽  
Bending Fatigue ◽  
Precision Forging ◽  
Bending Fatigue Test ◽  
Bending Fatigue Strength ◽  
Gear Profile

This paper deals with the evaluation of influence of the manufacturing methods precision forging and conventional hobbing on the bending fatigue strength of carburized gears. The forging has advantages in productivity and strength. The forged gear has a continuous directed fiber flow which runs along the gear profile. To clarify the effect of strength enhancement, a bending fatigue test is performed for the forged and the hobbed gears. The material of test gears is SCr420H in the JIS and all gears are carburized. The electrohydraulic servo-controlled fatigue tester is used in the constant stress-amplitude fatigue test. The strength is expressed by the fillet stress level, which is calculated by FEM. The obtained strengths of forged and hobbed gear are 1613 MPa and 1490 MPa, respectively. The strength of forged gear is increased 8% in comparison with that of the hobbed gear. The surface hardness is higher and the surface roughness is smaller in the forged gear, however, the residual stress is approximately same. The effect of improvement of the roughness by forging on the strength is small in 1%, and the main reason of the improvement of fatigue strength is considered as the continuous fiber flow.

An Approach for Solving the Contact Problem in Spur Gear Transmissions Considering Gear Misalignments

2015 ◽  
Author(s):  
V. Roda-Casanova ◽  
F. Sanchez-Marin ◽  
J. L. Iserte
Keyword(s):  
Contact Problem ◽  
Computational Cost ◽  
Element Model ◽  
Spur Gear ◽  
New Approach ◽  
Load Distributions ◽  
Bending Stresses ◽  
Gear Drives ◽  
Contact Pressures

Gear misalignments originate unwanted uneven load distributions that increase contact pressures and the bending stresses, reducing the service life of gear drives. Therefore, it is very important to take into account the misalignments in the determination of contact pressures when designing a gear transmission. Some of these misalignments are related to manufacturing and assembly errors, but others are produced by the deformation of the shafts when power is transmitted. These deformations cause misalignment of the gears, modifying the contact bearing and the pressure distribution, which modifies the deformation of the shafts, leading to a coupled problem not always easy to solve. In this work, a new approach to solve this problem is proposed, based on an iterative algorithm which uncouples the determination of the deformation of the shafts from the contact problem. The proposed approach has been tested through various configurations of spur gear drives. The obtained results are compared with those obtained using a finite element model, showing a good correlation between them, but with a significant reduction of the computational cost.

Analytical and experimental studies on wear in spur gear running in dry condition

2021 ◽  
pp. 1-30
Author(s):  
Sudhagar Selvam ◽  
L Bhaskara Rao
Keyword(s):  
Wear Rate ◽  
Contact Zone ◽  
Experimental Studies ◽  
Wear Test ◽  
Spur Gear ◽  
Test Method ◽  
Single Pair ◽  
Observation Method ◽  
Sliding Distance ◽  
Gear Profile

Abstract This study was performed to measure the extent of wear of unlubricated spur gears on the involute tooth. Contacts that roll and slide normally undergo wear. When material removal occurs due to surface wear from the gear profile, the surface pressure in the gear profile is redistributed. A mathematical model for predicting wear and wear pattern in spur gear has been developed. The prediction is based on wear rate equation, load shared by the tooth in single-pair contact zone and double-pair contact zone. The distribution of the contact pressure was determined using the Hertzian cylindrical contact theory. For determining the sliding distance of the gears, the two-point observation method (TPOM) was used. Sliding distance at pitch point of gear and pinion was zero, because theoretically at pitch point, both zero sliding and pure rolling occur. The pin on the wear test method was used to obtain the wear rate on the material and simplified to the time of measurement on the gear wear. Taguchi's method for design of experiment was used, which significantly reduced experimental time with less experiment.

Measurement and Validation of Dynamic Bending Stresses in Spur Gear Teeth

2005 ◽  
Author(s):  
Suren B. Rao ◽  
Vernon Schwanger ◽  
Douglas R. McPherson ◽  
Clay Rudd
Keyword(s):  
Spur Gear ◽  
Gear Teeth ◽  
Bending Stresses ◽  
Dynamic Bending

Finite Element Simulation of Bending Stress on Involute Spur Gear Tooth Profiles

2017 ◽  
Vol 30 ◽  
pp. 1-10
Author(s):  
Kolawole Adesola Oladejo ◽  
Dare Aderibigbe Adetan ◽  
Ayobami Samuel Ajayi ◽  
Oluwasanmi Oluwagbenga Aderinola
Keyword(s):  
Finite Element ◽  
Finite Element Simulation ◽  
Gear Tooth ◽  
Spur Gear ◽  
Bending Stress ◽  
Relative Deviation ◽  
Element Simulation ◽  
Maximum Relative Deviation ◽  
Bending Stresses ◽  
Good Agreement

This study investigated bending stress distribution on involute spur gear tooth profiles with pressure angle of 20 ̊ but different modules 2.5, 4.0 and 6.0 mm, using a finite-element-based simulation package - AutoFEA JL Analyzer. The drafting of the geometry for the three gear tooth profiles were implemented on the platform of VB-AutoCAD customized environment, before importing to the package. These were separately subjected to analysis for bending stresses for a point at the tooth fillet region with appropriate settings of material property, load and boundary conditions. With the same settings, the bending stresses were computed analytically using American Gear Manufacturers Association (AGMA) established equation. The results of the two approaches were in good agreement, with maximum relative deviation of 4.38%. This informed the confidence in the implementation of the package to investigate the variation of bending stress within the gear tooth profile. The simulation revealed decrease in the bending stresses at the investigated regions with increase in the module of the involute spur-gear. The study confirms that Finite element simulation of stresses on gear tooth can be obtained accurately and quickly with the AutoFEA JL Analyzer.

scholarly journals Effects of Rim Thickness on Spur Gear Bending Stress

1994 ◽  
Vol 116 (4) ◽  
pp. 1157-1162 ◽  
Author(s):  
G. D. Bibel ◽  
S. K. Reddy ◽  
M. Savage ◽  
R. F. Handschuh
Keyword(s):  
Finite Element Analysis ◽  
Finite Element ◽  
High Power ◽  
Design Parameter ◽  
Gear Tooth ◽  
Spur Gear ◽  
Bending Stress ◽  
Element Analysis ◽  
Bending Stresses

Thin rim gears find application in high-power, lightweight aircraft transmissions. Bending stresses in thin rim spur gear tooth fillets and root areas differ from the stresses in solid gears due to rim deformations. Rim thickness is a significant design parameter for these gears. To study this parameter, a finite element analysis was conducted on a segment of a thin rim gear. The rim thickness was varied and the location and magnitude of the maximum bending stresses reported. Design limits are discussed and compared with the results of other researchers.

A New Photoelastic Investigation of the Dynamic Bending Stress of Spur Gears

2003 ◽  
Vol 125 (2) ◽  
pp. 365-372 ◽  
Author(s):  
Ming-Jong Wang
Keyword(s):  
Critical Points ◽  
Gear Tooth ◽  
Spur Gear ◽  
Behavioral Characteristics ◽  
Spur Gears ◽  
Bending Stress ◽  
Dynamic Effects ◽  
Contact Points ◽  
Photoelastic Investigation ◽  
Bending Stresses

In this paper, the maximum tensile bending stress (MTBS) and the critical point in the root fillet of spur gear tooth during transmission are determined by a digital photoelastic system involving real time imaging. The behavioral characteristics of the bending stresses of the gear tooth are analyzed at different rotation speeds, transmitted torques, and contact points. Then, the dynamic effects, the various critical points and the maximum tensile bending stresses are compared experimentally and theoretically, and discussed. Finally, the best approaches for determining the maximum bending stress and its position in the root fillet of spur gear tooth are recommended.

A Study of Spur Gear Geometry Factor Through Complex Potential Analysis

1989 ◽  
Vol 111 (3) ◽  
pp. 433-438 ◽  
Author(s):  
A. Cardou ◽  
G. V. Tordion
Keyword(s):  
Complex Potential ◽  
Sliding Friction ◽  
Spur Gear ◽  
Potential Method ◽  
Theory Of Elasticity ◽  
Spur Gears ◽  
Geometry Factor ◽  
The Coefficient Of Friction ◽  
Bending Stresses ◽  
Complex Potential Method

Bending stresses in spur gears have been obtained analytically using the Complex Potential Method of the two-dimensional theory of elasticity and conformal mapping of the tooth profile. Effects of profile shift and sliding friction on geometry factor have been studied for 20 deg pressure angle and numbers of teeth ranging from 20 to 150. It has been shown how these results can be applied to obtain a geometry factor corrected to include either the profile or the coefficient of friction effect in a given gear pair.

Sign in / Sign up

Export Citation Format

Share Document