Using Constraint Management Techniques to Design Spur and Helical Gears

1992 ◽  
Author(s):  
Rajiv Agrawal ◽  
Natarajan Sridhar ◽  
Gary L. Kinzel
Keyword(s):  
Mathematical Formulation ◽  
Spur Gears ◽  
Helical Gears ◽  
General Design ◽  
Gear Design ◽  
Constraint Management ◽  
Management Techniques

Abstract This paper presents the use of constraint management techniques to design spur and helical gears. The constraints for gear design are presented in a declarative manner such that they can be incorporated in a general Design Shell environment. A declarative representation allows the designer to experiment with a number of different designs and perform “what-if” scenarios. Since spur gears form a subset of helical gears, the mathematical formulation is presented for helical gears only. The analysis of helical gears is based on the AGMA/ANSI Standard 2001-B88.

Revisiting Generation and Meshing Properties of Beveloid Gears

2017 ◽  
Vol 139 (9) ◽  
Author(s):  
Alessio Artoni ◽  
Massimo Guiggiani
Keyword(s):  
Tooth Surface ◽  
Generation Process ◽  
Spur Gears ◽  
Helical Gears ◽  
Additional Degree ◽  
Beveloid Gears ◽  
Fixed Space ◽  
Fixed Axis ◽  
The One ◽  
Special Case

The teeth of ordinary spur and helical gears are generated by a (virtual) rack provided with planar generating surfaces. The resulting tooth surface shapes are a circle-involute cylinder in the case of spur gears, and a circle-involute helicoid for helical gears. Advantages associated with involute geometry are well known. Beveloid gears are often regarded as a generalization of involute cylindrical gears involving one additional degree-of-freedom, in that the midplane of their (virtual) generating rack is inclined with respect to the axis of the gear being generated. A peculiarity of their generation process is that the motion of the generating planar surface, seen from the fixed space, is a rectilinear translation (while the gear blank is rotated about a fixed axis); the component of such translation that is orthogonal to the generating plane is the one that ultimately dictates the shape of the generated, envelope surface. Starting from this basic fact, we set out to revisit this type of generation-by-envelope process and to profitably use it to explore peculiar design layouts, in particular for the case of motion transmission between skew axes (and intersecting axes as a special case). Analytical derivations demonstrate the possibility of involute helicoid profiles (beveloids) transmitting motion between skew axes through line contact and, perhaps more importantly, they lead to the derivation of designs featuring insensitivity of the transmission ratio to all misalignments within relatively large limits. The theoretical developments are confirmed by various numerical examples.

Low excitation spur gears with variable tip diameter

2021 ◽  
Vol 263 (5) ◽  
pp. 1275-1285
Author(s):  
Joshua Götz ◽  
Sebastian Sepp ◽  
Michael Otto ◽  
Karsten Stahl
Keyword(s):  
Transmission Error ◽  
Spur Gear ◽  
Low Noise ◽  
Spur Gears ◽  
Mesh Stiffness ◽  
Helical Gears ◽  
Axial Forces ◽  
Tooth Width ◽  
Drive Trains ◽  
Static Transmission Error

One important source of noise in drive trains are transmissions. In numerous applications, it is necessary to use helical instead of spur gear stages due to increased noise requirements. Besides a superior excitation behaviour, helical gears also show additional disadvantageous effects (e.g. axial forces and tilting moments), which have to be taken into account in the design process. Thus, a low noise spur gear stage could simplify design and meet the requirements of modern mechanical drive trains. The authors explore the possibility of combining the low noise properties of helical gears with the advantageous mechanical properties of spur gears by using spur gears with variable tip diameter along the tooth width. This allows the adjustment of the total length of active lines of action at the beginning and end of contact and acts as a mesh stiffness modification. For this reason, several spur gear designs are experimentally investigated and compared with regard to their excitation behaviour. The experiments are performed on a back-to-back test rig and include quasi-static transmission error measurements under load as well as dynamic torsional vibration measurements. The results show a significant improvement of the excitation behaviour for spur gears with variable tip diameter.

Coupled Dynamic and Vibration Analysis of Beveloid Geared System

2012 ◽  
Vol 215-216 ◽  
pp. 917-920
Author(s):  
Rong Fan ◽  
Chao Sheng Song ◽  
Zhen Liu ◽  
Wen Ji Liu
Keyword(s):  
Transmission Error ◽  
Time Varying ◽  
Spur Gears ◽  
Dynamic Coupling ◽  
Nonlinear Dynamic Model ◽  
Mesh Stiffness ◽  
Hypoid Gears ◽  
Helical Gears ◽  
Beveloid Gears ◽  
Vibration Model

Dynamic modeling of beveloid gears is less developed than that of spur gears, helical gears and hypoid gears because of their complicated meshing mechanism and 3-dimsional dynamic coupling. In this study, a nonlinear systematic coupled vibration model is created considering the time-varying mesh stiffness, time-varying transmission error, time-varying rotational radius and time-varying friction coefficient. Numerical integration applying the explicite Runge-Kutta formula and the implicit direct integration is used to solve the nonlinear dynamic model. Also, the dynamic characteristics of the marine gear system are investigated.

scholarly journals Research on the Design and Modification of Asymmetric Spur Gear

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Xiaohe Deng ◽  
Lin Hua ◽  
Xinghui Han
Keyword(s):  
Computer Aided Design ◽  
Design Method ◽  
Geometric Model ◽  
Simulation Method ◽  
Transmission Error ◽  
Spur Gear ◽  
Geometric Shape ◽  
Spur Gears ◽  
Gear Design ◽  
Aided Design

A design method for the geometric shape and modification of asymmetric spur gear was proposed, in which the geometric shape and modification of the gear can be obtained directly according to the rack-cutter profile. In the geometric design process of the gear, a rack-cutter with different pressure angles and fillet radius in the driving side and coast side was selected, and the generated asymmetric spur gear profiles also had different pressure angles and fillets accordingly. In the modification design of the gear, the pressure angle modification of rack-cutter was conducted firstly and then the corresponding modified involute gear profile was obtained. The geometric model of spur gears was developed using computer-aided design, and the meshing process was analyzed using finite element simulation method. Furthermore, the transmission error and load sharing ratio of unmodified and modified asymmetric spur gears were investigated. Research results showed that the proposed gear design method was feasible and desired spur gear can be obtained through one time rapid machining by the method. Asymmetric spur gear with better transmission characteristic can be obtained via involute modification.

On the influence of helix angle and face width on gear windage losses

2015 ◽  
Vol 230 (7-8) ◽  
pp. 1101-1112 ◽  
Author(s):  
Nicolas Voeltzel ◽  
Yann Marchesse ◽  
Christophe Changenet ◽  
Fabrice Ville ◽  
Philippe Velex
Keyword(s):  
Computational Fluid Dynamic ◽  
Fluid Dynamic ◽  
Helix Angle ◽  
Spur Gears ◽  
Power Losses ◽  
Flow Rates ◽  
Helical Gears ◽  
Face Width ◽  
Loss Prediction ◽  
Simulated Flow

This paper investigates the windage power losses generated by helical gears rotating in pure air based on experimental results and a computational fluid dynamic code. It is found that the simulated flow patterns are totally different from those calculated for spur gears and that both tooth face width and helix angle are influential. The windage losses derived from Dawson’s and Townsend’s formulae are critically assessed using computational fluid dynamic results thus highlighting the limits of a unique formulation for accurate windage loss prediction. Finally, an analytical approach is suggested which gives good results providing that the flow rates at the boundaries of the inter-tooth domains can be estimated.

scholarly journals Effect of Helix Angle on the Gear Design Parameters in Helical Gears

2019 ◽  
Vol 8 (10) ◽  
pp. 887-890
Keyword(s):  
Helix Angle ◽  
Contact Stresses ◽  
Design Parameters ◽  
Screw Compressor ◽  
Bending Stress ◽  
Contact Ratio ◽  
Helical Gears ◽  
Gear Design ◽  
Overlap Ratio ◽  
Lower Noise

Screw compressor demands quite operation. For getting lower noise it is important to have higher contact ratio. Contact ratio can be increased by increasing the Helix angle i .e. indirectly increasing overlap ratio. The paper represents the effect of change in design parameters with respect to helix angle with the keeping same module and same centre distance. Higher helix angle leads lower bending and contact stresses. The study was conducted for screw electrical compressor. Gear was design for fixed parameters except helix angle. Also the contact stresses are analyzed (FEA) on ANSYS. The result from the calculation and FEA are compared for contact stress as well as bending stress.

Contribution on the Optimization of the Spur Gears Design Process Using Software Application

2014 ◽  
Vol 658 ◽  
pp. 117-122
Author(s):  
Gheorghe Plesu ◽  
Stelian Cazan
Keyword(s):  
Programming Language ◽  
Design Process ◽  
Optimization Process ◽  
Spur Gears ◽  
Operational Method ◽  
Mathematical Functions ◽  
Standard Methods ◽  
Software Application ◽  
Gear Design ◽  
Design Steps

This paper illustrates a method, in conformity with Standards [10 - 14], regarding gear design. The optimization process using this method consists in reducing the number of design steps and also in its accuracy. This method takes into consideration the functionality of gears. This method, called also the operational method [1], involves 10 kinematic and dynamic restrictions, that provide a direct calculus of gears, without any iterations. The standard methods require successive iterations, until the appropriate result is obtained. The comparison between these methods is presented below. The kinematic and dynamic restrictions, being defined as mathematical functions, could easily be implemented in a programming language.

A Visual Basic Program to Calculate Gear Features

2001 ◽  
Author(s):  
Edward M. Vavrek
Keyword(s):  
Engineering Students ◽  
Selection Process ◽  
Visual Basic ◽  
Spur Gear ◽  
Basic Program ◽  
Design Analysis ◽  
Spur Gears ◽  
Analysis Program ◽  
Gear Design ◽  
Visual Basic Program

Abstract This paper describes a spur gear design analysis program written in visual basic. The program is used to assist engineering students in the design of spur gears, which involves many calculations and decisions. This software program simplifies and streamlines the design and selection process. Since the visual basic program is event driven, the user can go through the program by inputting values into text boxes and then initiating events by clicking on command buttons. An important feature of this program is the ability to insert pictures, tables, graphs, drawings, and figures to enhance the program functionality. Most inputs are taken from graphs, charts, or tables so the user knows where and how the information is obtained and used. Outputs are shown with their appropriate figures, drawings, or calculation formulas to assist the user in understanding how the output was derived. The software has the advantage of making minor changes to the problem quickly and easily to see how the output is affected.

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