Effect of Tooth Profile on the Bulk Temperature of Spur Gears

Abstract Finish roll forming under the constant center distance by forced feed of tool can be conceived as a method of eliminating errors in conventional form rolling under constant loads. This method generates a high-precision tooth profile by low-speed form rolling when a high rigid screw or cam is used as loading parts. In this study, the high-speed rolling conditions of this method for necessary to be applied in practical situations are discussed. The following conclusions are obtained. When the following design data are given (module, number of teeth, addendum modification coefficient, prescribed design precision, and material characteristics), the accuracy of rolled gear can be predicted from the relationship between the required feed for the tool and the theoretically calculated plastic deformation on the tooth profile. These conclusions are verified experimentally. For example, the tooth accuracy of rolled gears with module 5 can improve from JIS class 3 to JIS class 0 or 1 when the load Fmax is 4 to 5kN and the pitch line velocity is 7 m/min.

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Effects of Drive Side Pressure Angle on Gear Fatigue Crack Propagation Life for Spur Gears With Symmetric and Asymmetric Teeth

Volume 9: Mechanics of Solids, Structures, and Fluids ◽

10.1115/imece2019-11510 ◽

2019 ◽

Author(s):

Fatih Karpat ◽

Oguz Dogan ◽

Tufan Yilmaz ◽

Celalettin Yuce ◽

Onur Can Kalay ◽

...

Keyword(s):

Fatigue Crack ◽

Crack Propagation ◽

Fatigue Crack Propagation ◽

Tooth Profile ◽

Spur Gears ◽

Pressure Angle ◽

Side Pressure ◽

Machine Elements ◽

Fatigue Crack Propagation Life ◽

Initial Starting

Abstract Today gears are one of the most crucial machine elements in the industry. They are used in every area of the industry. Due to the high performances of the gears, they are also used in aerospace and wind applications. In these areas due to the high torques, unstable conditions, high impact forces, etc. cracks can be seen on the gear surface. During the service life, these cracks can be propagated and gear damages can be seen due to the initial cracks. The aim of this study is to increase the fatigue crack propagation life of the spur gears by using asymmetric tooth profile. Nowadays asymmetric gears have a very important and huge usage area in the industry. In this study, the effects of drive side pressure angle on the fatigue crack propagation life are studied by using the finite element method. The initial starting points of the cracks are defined by static stress analysis. The starting angles of the cracks are defined constant at 45°. The crack propagation analyses are performed in ANSYS SMART Crack-Growth module by using Paris Law. Four different drive side pressure angles (20°-20°, 20°-25°, 20°-30° and 20°-35°) are investigated in this study. As a result of the study the fatigue crack propagation life of the gears is increased dramatically when the drive side pressure angle increase. This results show that the asymmetric tooth profile not only decrease the bending stress but also increase the fatigue crack propagation life strongly.

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Investigation of the thermal stiffness and thermal tooth profile modification of spur gears

Journal of the Brazilian Society of Mechanical Sciences and Engineering ◽

10.1007/s40430-020-2234-5 ◽

2020 ◽

Vol 42 (4) ◽

Author(s):

Biao Luo ◽

Wei Li ◽

Chunming Fu ◽

Linsheng Li ◽

Xinxin Zhang

Keyword(s):

Tooth Profile ◽

Spur Gears ◽

Profile Modification ◽

Tooth Profile Modification

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Explicit Parametric Method for Optimal Spur Gear Tooth Profile Definition

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.633.87 ◽

2013 ◽

Vol 633 ◽

pp. 87-102 ◽

Cited By ~ 5

Author(s):

Ivana Atanasovska ◽

Radivoje Mitrovic ◽

Dejan Momcilovic

Keyword(s):

Gear Tooth ◽

Load Capacity ◽

Parametric Method ◽

Spur Gear ◽

Tooth Profile ◽

Spur Gears ◽

Element Analysis ◽

Engineering Research ◽

Profile Optimization ◽

Current Engineering

The gear tooth profile has an immense effect on the main operating parameters of gear pairs (load capacity, working life, efficiency, vibrations, etc). In current engineering research and practice, there is a strong need to develop methods for tooth profile optimization. In this paper a new method for selecting the optimal tooth profile parameters of spur gears is described. This method has been named the Explicit Parametric Method (EPM). The addendum modification coefficient, radius of root curvature, and pressure angle of the basic rack for cylindrical gears, have been identified as the main tooth profile parameters of spur gears. Therefore, the EPM selects the optimal values for these three tooth profile parameters. Special attention has been paid to develop a method of adjustment for the particular working conditions and explicit optimization requirements. The EPM for optimal tooth profile parameters of gears uses contact nonlinear Finite Element Analysis (FEA) for calculation of deformations and stresses of gear pairs, in addition to explicit comparative diagrams for optimal tooth profile parameter selection.

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