Stress Analysis of Spherical Gear Sets

2009 ◽  
Author(s):  
Li-Chi Chao ◽  
Chung-Biau Tsay
Keyword(s):  
Gear Tooth ◽  
Three Dimensional ◽  
Contact Analysis ◽  
Design Parameters ◽  
Tooth Contact Analysis ◽  
Tooth Contact ◽  
Contact Points ◽  
Tooth Surfaces ◽  
Loaded Tooth Contact Analysis ◽  
Spherical Gear

The spherical gear is a new type of gear proposed by Mitome et al. [1]. Different from that of the conventional spur or helical gear sets, the spherical gear set can allow variable shaft angles and large axial misalignments without gear interference during the gear drive meshing [1, 2]. Geometrically, the spherical gear has two types of gear tooth profiles, the concave tooth and convex tooth. In practical transmission applications, the contact situation of a spherical gear set is very complex. To obtain a more realistic simulation result, the loaded tooth contact analysis (LTCA) has been performed by employing the finite element method (FEM). According to the derived mathematical model of spherical gear tooth surfaces, an automatic meshes generation program for three-dimensional spherical gears has been developed. Beside, tooth contact analysis (TCA) of spherical gears has been performed to simulate the contact points of the spherical gear set. Furthermore, the contact stress contours of spherical gear tooth surfaces and bending stress of tooth roots have been investigated by giving the design parameters, material properties, loadings and boundary conditions of spherical gears.

Loaded tooth contact analysis of orthogonal face-gear drives

2012 ◽  
Vol 226 (9) ◽  
pp. 2309-2319 ◽  
Author(s):  
Yan-zhong Wang ◽  
Can-hui Wu ◽  
Kang Gong ◽  
Shu Wang ◽  
Xing-fu Zhao ◽  
...  
Keyword(s):  
Gear Tooth ◽  
Three Dimensional ◽  
Contact Analysis ◽  
Face Gear ◽  
Tooth Contact Analysis ◽  
Tooth Contact ◽  
Bearing Contact ◽  
Tooth Surfaces ◽  
Loaded Tooth Contact Analysis ◽  
Gear Drives

In order to analyze the transmission performance of face-gear in real working condition, a calculational approach for load equivalent error of alignment has been investigated with the purpose of analyzing the support system and tooth deformation of face-gear drives. Then, the equations of contact path of loaded tooth contact analysis have been established based on load equivalent error of alignment. For the purpose of analyzing the bearing contact, the curvatures of face-gear and pinion have been presented. Tooth contact deformation and bending deformation have been developed using elasticity and three-dimensional FEA. Loaded tooth contact analysis and contact stress have been considered to simulate the contact and meshing of the gear tooth surfaces and to calculate the evolution of load distribution, bearing contact, transmission errors, and contact stresses of the gear drive along the cycle of meshing. The performed research proves that the proposed loaded tooth contact analysis method can effectively solve the meshing characteristic problem of face-gear drives system. The results are illustrated with numerical examples.

An Ease-Off Based Method for Loaded Tooth Contact Analysis of Hypoid Gears Having Local and Global Surface Deviations

2010 ◽  
Vol 132 (7) ◽  
Author(s):  
M. Kolivand ◽  
A. Kahraman
Keyword(s):  
Gear Tooth ◽  
Contact Analysis ◽  
Tooth Surface ◽  
Hypoid Gear ◽  
Tooth Contact Analysis ◽  
Tooth Contact ◽  
Hypoid Gears ◽  
Surface Deviations ◽  
Tooth Surfaces ◽  
Loaded Tooth Contact Analysis

Actual hypoid gear tooth surfaces do deviate from the theoretical ones either globally due to manufacturing errors or locally due to reasons such as tooth surface wear. A practical methodology based on ease-off topography is proposed here for loaded tooth contact analysis of hypoid gears having both local and global deviations. This methodology defines the theoretical pinion and gear tooth surfaces from the machine settings and cutter parameters, and constructs the surfaces of the theoretical ease-off and roll angle to compute for the unloaded contact analysis. This theoretical ease-off topography is modified based on tooth surface deviations and is used to perform a loaded tooth contact analysis according to a semi-analytical method proposed earlier. At the end, two examples, a face-milled hypoid gear set having local deviations and a face-hobbed one having global deviations, are analyzed to demonstrate the effectiveness of the proposed methodology in quantifying the effect of such deviations on the load distribution and the loaded motion transmission error.

A Novel Loaded Tooth Contact Analysis Procedure with Application to Internal-External Straight Bevel Gear Mesh in Pericyclic Drive

2020 ◽  
pp. 1-22
Author(s):  
Tanmay D. Mathur ◽  
Edward C. Smith ◽  
Robert C. Bill
Keyword(s):  
Gear Tooth ◽  
Contact Analysis ◽  
Bevel Gear ◽  
Gear Train ◽  
Initial Surface ◽  
Tooth Contact Analysis ◽  
Tooth Contact ◽  
Gear Mesh ◽  
Number Of Teeth ◽  
Loaded Tooth Contact Analysis

Abstract A comprehensive numerical loaded tooth contact analysis (LTCA) model is proposed for straight bevel gears that exhibit large number of teeth in contact, well beyond involute line of action limits. This kind of contact is observed when the meshing gears have conformal surfaces, as in a Pericyclic mechanical transmission, and is traditionally analysed using finite element simulations. The Pericyclic drive is kinematically similar to an epicyclic bevel gear train, and is characterized by load sharing over large number of teeth in an internal-external bevel gear mesh, large shaft angles (175° - 178°), nutational gear motion, and high reduction ratio. The contact region spreads over a large area on the gear tooth flank due to high contacting surface conformity. Thus, a thick plate Finite Strip method (FSM) was utilized to accurately calculate the gear tooth bending deflection. Based on tooth deformation calculation model, and accounting for initial surface separation, a variational framework is developed to simultaneously solve for load distribution and gear tooth deformation. This is followed by calculation of contact stress, bending stress, mesh stiffness, and transmission error. The results demonstrate the high power density capabilities of the Pericyclic drive and potential for gear noise reduction. The model developed herein is applied with real gear tooth surfaces, as well.

Compound transmission principle analysis of eccentric curve-face gear pair with curvilinear-shaped teeth based on tooth contact analysis

2021 ◽  
pp. 095440622110470
Author(s):  
Chao Lin ◽  
Yu Wang ◽  
Yanan Hu ◽  
Yongquan Yu
Keyword(s):  
Axial Direction ◽  
Contact Analysis ◽  
Gear Pair ◽  
Face Gear ◽  
Tooth Contact Analysis ◽  
Tooth Contact ◽  
Contact Points ◽  
Tooth Surfaces ◽  
Set Up ◽  
Curve Face

A new type of compound transmission gear pair was put forward, called eccentric curve-face gear pair with curvilinear-shaped teeth. It could realize reciprocating motion of the gear shaft when the intersecting shafts achieve transferring motion and power through its unique tooth profile. The compound transmission principle of this gear pair was fully established based on the profile-closure process of axial direction and meshing process of the end face. The tooth surfaces of the eccentric curve-face gear and non-circular gear were generated. The contact paths of different teeth were obtained, and the compound transmission principle of eccentric curve-face gear pair with curvilinear-shaped teeth was verified by tooth contact analysis. By analyzing the mechanical characteristics of time-varying contact points, the changing rule of contact force was studied, and the compound transmission principle of the gear pair was further revealed from mechanics. Moreover, the experimental platform for transmission of eccentric curve-face gear pair with curvilinear-shaped teeth was set up to measure the motion law and contact area, and the correctness of the analysis results was verified.

Coupled Tooth Contact Analysis of Intersected Beveloid Gears for Marine Transmissions

2013 ◽  
Author(s):  
Caichao Zhu ◽  
Haixia Wang ◽  
Mingyong Liu ◽  
Xuesong Du ◽  
Chaosheng Song
Keyword(s):  
Gear Tooth ◽  
Contact Analysis ◽  
Tooth Surface ◽  
Tooth Contact Analysis ◽  
Tooth Contact ◽  
Contact Patterns ◽  
Beveloid Gears ◽  
Shaft Angle ◽  
Loaded Tooth Contact Analysis ◽  
Mesh Condition

Beveloid gears are widely applied in fields like ships, automobiles and industrial precision transmissions. In this paper, the formulas of the beveloid gear tooth surface used in marine transmissions were derived and a mesh model for the intersected beveloid gear pair was setup. Then loaded tooth contact analysis was performed using the finite element method considering the coupling of the assembly errors and the elastic deformation of tooth surface. Through the analysis, the influences of assembly errors on contact patterns, mesh force and tooth surface deformations were investigated. In a further step, the tooth profile modifications were performed to alleviate the edge contact and a subsequent major improvement of the mesh condition was obtained. Finally, loaded tooth contact experiments for marine gearboxes with small shaft angle were conducted. The tested results showed good correlation with the computed results. This work may provide some value for the practical design aiming at improved contact characteristics of the beveloid gears with intersected axes.

scholarly journals Computer-aided design and loaded tooth contact analyses of bevel gear pair having straight teeth by different loaded torques

2020 ◽  
Vol 21 (1) ◽  
pp. 109
Author(s):  
Sándor Bodzás
Keyword(s):  
Computer Aided Design ◽  
Three Dimensional ◽  
Computer Software ◽  
Bevel Gear ◽  
Gear Pair ◽  
Tooth Contact Analysis ◽  
Tooth Contact ◽  
Contact Points ◽  
Loaded Tooth Contact Analysis ◽  
Aided Design

The aim of this publication is to show how to integrate the designing process of straight bevel gears into a computer software so it can be further used for making the three-dimensional (CAD) model of the gear pair. During meshing the driven and the driving gears engage gradually so contact points can be mathematically determined between the element pairs according to the developed coordinate system's arrangement. With my-developed computer software, I designed a certain bevel gear pair having straight teeth. Naturally, many different types of this pair could be designed. After that Loaded Tooth Contact Analysis (LTCA) have been done − by normal stress, normal deformation and normal elastic strain parameters. The aim of the LTCA is the analysis of the connection tooth zone in mechanical aspects by different loads. If the received parameters are not appropriate, you can return to the mechanical designing process where the starting parameters of the gear could be modified. Different load torques were used to determine the established mechanical parameters of the elements.

Gear Contact Model and Loaded Tooth Contact Analysis of a Three-Dimensional, Thin-Rimmed Gear

2002 ◽  
Vol 124 (3) ◽  
pp. 511-517 ◽  
Author(s):  
Shuting LI
Keyword(s):  
Three Dimensional ◽  
Contact Analysis ◽  
Deformation Model ◽  
Tooth Contact Analysis ◽  
Tooth Contact ◽  
Load Distributions ◽  
Dimensional Finite Element ◽  
Calculation Results ◽  
Loaded Tooth Contact Analysis ◽  
Three Dimensional Finite Element

This paper performs loaded tooth contact analysis of a three-dimensional, thin-rimmed gear (3DTRG) by presenting a method that combines the mathematical programming method with the three-dimensional, finite element method (3DFEM). Also, a face-contact and whole gear deformation model is used for the 3DTRG. 3DFEM programs for the contact analysis and strength calculation of the 3DTRG are developed successfully in a personal computer. By using this program, 3D tooth load distributions, tooth root strains and the tooth contact pattern of the 3DTRG are obtained. Calculation results are proved to be correct by experiments.

Surface design and tooth contact analysis of an innovative modified spur gear with crowned teeth

2005 ◽  
Vol 219 (2) ◽  
pp. 193-207 ◽  
Author(s):  
J-L Li ◽  
S-T Chiou
Keyword(s):  
Gear Tooth ◽  
Point Contact ◽  
Spur Gear ◽  
Contact Analysis ◽  
Tooth Surface ◽  
Tooth Contact Analysis ◽  
Tooth Contact ◽  
Surface Design ◽  
Tooth Surfaces ◽  
Meshing Characteristics

An innovative modified spur gear with crowned teeth and its generating mechanism are proposed in this study. The main purpose of tooth surface modification is to change line contact to point contact at the middle of gear tooth surfaces in order to avoid edge contact resulting from possible unavoidable axial misalignment. Moreover, the surface of one gear tooth can be generated with just one cutting process, thereby facilitating easy manufacturing. Based on gearing theory, the model for surface design is developed. A tooth contact analysis (TCA) model for the modified gear pair is also built to investigate meshing characteristics, so that transmission errors (TEs) under assembly errors can also be studied. Examples are included to verify the correctness of the models developed and to demonstrate gear characteristics.

Tooth Contact and 3-D Stress Analysis of Involute Helical Gears

1992 ◽  
Author(s):  
M. A. Sahir Arikan ◽  
Mustafa Tamar
Keyword(s):  
Stress Analysis ◽  
Gear Tooth ◽  
Contact Point ◽  
Helical Gear ◽  
Contact Analysis ◽  
Contact Lines ◽  
Coordinate Systems ◽  
Tooth Contact Analysis ◽  
Tooth Contact ◽  
Contact Points

Abstract An involute helical gear tooth is modelled by using helical gear geometry and a solid modelling package, and this model is used to determine the load distribution on contact lines of mating teeth, and to make the stress analysis by using three-dimensional tetrahedron finite elements with four nodes. Tooth contact analysis is made by using the theory of gearing. Geometry of the cutting tool is used to determine the surface equations of the pinion and the gear in their own coordinate systems, then these equations are transformed to a fixed coordinate system to make the tooth contact analysis and to find the coordinates of contact points. Found contact point coordinates are then transformed back to the original coordinate systems and contact lines on helical gear teeth are formed. Results of this analysis is used to determine the application points and directions of the forces acting on the tooth. Then the stiffnesses of meshing teeth and the load distributions on contact lines are found, which are then used for stress analysis.

An Ease-Off Based Method for Loaded Tooth Contact Analysis of Hypoid Gears Having Local and Global Surface Deviations

2009 ◽  
Author(s):  
M. Kolivand ◽  
A. Kahraman
Keyword(s):  
Gear Tooth ◽  
Contact Analysis ◽  
Tooth Surface ◽  
Surface Wear ◽  
Tooth Contact Analysis ◽  
Tooth Contact ◽  
Hypoid Gears ◽  
Manufacturing Errors ◽  
Spiral Bevel ◽  
Loaded Tooth Contact Analysis

Manufacturing errors typically cause real (measured) spiral bevel and hypoid gear surfaces to deviate from the theoretical ones globally. Tooth surface wear patterns accumulated through the life span of the gear set are typically local deviations that are aggravated especially in case of edge contact conditions. An accurate and practical methodology based on ease-off topography is proposed in this study to perform loaded tooth contact analysis of spiral bevel and hypoid gears having both types of local and global deviations. It starts with definition of the theoretical pinion and gear tooth surfaces from the machine settings and cutter parameters, and constructs the theoretical ease-off and roll angle surfaces to compute unloaded contact analysis. Manufacturing errors and localized surface wear deviations are considered to update the theoretical ease-off to form a new ease-off surface that is used to perform a loaded tooth contact analysis according to the semi-analytical method proposed earlier. At the end, a numerical example with locally deviated surfaces is analyzed to demonstrate the effectiveness of the proposed methodology as well as quantifying the effect of such deviations on load distribution and the loaded motion transmission error.

Sign in / Sign up

Export Citation Format

Share Document