Determination of gear tooth friction by disc machine

1991 ◽  
Vol 24 (5) ◽  
pp. 269-275 ◽  
Author(s):  
K.L. Johnson ◽  
D.I. Spence
Keyword(s):  
Gear Tooth

A Multi-Purpose Planetary Gear Testing Machine for Studies of Gear Drive Dynamics, Efficiency, and Lubrication

1973 ◽  
Vol 95 (4) ◽  
pp. 1123-1130 ◽  
Author(s):  
R. Kasuba ◽  
E. I. Radzimovsky
Keyword(s):  
Gear Tooth ◽  
Measurement Techniques ◽  
Testing Machine ◽  
Planetary Gear ◽  
Gear Drive ◽  
Operational Characteristics ◽  
Surface Durability ◽  
Drive Dynamics ◽  
Selection Of

Feasibility of a multi-purpose testing machine for research studies in gearing has been demonstrated with construction of a unique gear testing machine with a differential planetary gear drive. This machine was used in such interdependent studies as determination of instantaneous gear tooth engagement loads, minimum film thicknesses, and gear efficiencies. With minimal structural and mechanical modifications, this gear research machine can be used for studies of surface durability, thermal distribution in gear meshing zones, and effects of variable torques and torsional oscillations on performance of gearing. Most of these studies could be conducted simultaneously. Upon selection of appropriate gear ratios, this machine was operated either with one or two stationary gears. Presence of stationary gears simplified greatly the measurement techniques and increased the reliability of tests. This machine can accommodate spur, helical or any special type of gearing. Design and operational characteristics of this machine, as well as a short summary of research projects performed on this machine, are presented in this paper.

Geometric Calculations of the Chamfered Tip and the Protuberance Undercut of a Tooth Profile

2011 ◽  
Author(s):  
Milos Nemcek ◽  
Zdenek Dejl
Keyword(s):  
Mass Production ◽  
Gear Tooth ◽  
Tooth Profile ◽  
Measuring Device ◽  
Car Industry ◽  
Industry Standard ◽  
Tooth Flank ◽  
Computing Method ◽  
Circle Diameter

Nowadays special modified tools are mostly used for rough or semi-finishing milling in the mass production of ground or shaved gears today. These modifications ensure the desired chamfer at the head or the undercut at the bottom of the gear tooth. Diameters of the beginning and the end of the operational involute (exact knowledge of them is necessary for the calculation of important meshing parameters) are found by using several techniques. The first one is the simulation of the generating action of a hob tooth using suitable graphic software with the subsequent measuring of these diameters from the envelope of hob tooth positions which was created. The second one is measuring directly on the gear manufactured using a measuring device. These simulations or measuring are often not performed and the tool with recommended parameters of the protuberance or the ramp is simply chosen by an educated guess [1]. But it is not an acceptable technique in a mass production (car industry). Standard DIN 3960 [2] gives a certain manual for the determination of these diameters. It suggests the iterative method for the calculation of the chamfer beginning circle diameter but without a reliable guideline. And as regards the protuberance, it refers to the correct calculation only in theory. This paper deals with the computing method to determine diameters of the beginning and the end of the function part of a tooth flank involute. It is designed for a specified tool with modifications for creating the chamfer or the protuberance undercut. The paper also takes into account the necessary shaving (grinding) stock or the backlash. Furthermore it refers to possible problems when the basic profile of the generating tool with the protuberance is designed from the basic rack tooth profile.

Calculation of helical gear’s basic parameters using COP-data acquired by optical 3D digitizer

2011 ◽  
Vol 225 (12) ◽  
pp. 2953-2962 ◽  
Author(s):  
P Asgharifard-Sharabiani ◽  
A Hannaneh ◽  
M Nikkhah-Bahrami
Keyword(s):  
Gear Tooth ◽  
Control Process ◽  
Surface Fitting ◽  
Optical Data ◽  
Tooth Surface ◽  
Cylinder Surface ◽  
Quality Control Process ◽  
Basic Parameters ◽  
Cloud Of Points

Gears are industrial components with a precise geometry. Identification of their basic parameters plays an important role in their reverse design and quality control process. This article describes a new approach for the calculation of helical gear’s basic parameters using optical data acquired by 3D digitizer. This approach is implemented by acquiring cloud-of-points data (COP-data) from the bearing seats and gear tooth surface. Cylinder surface fitting through COP-data acquired from bearing seats is performed for the determination of gear axis of rotation. In a final step, involute helicoid surface fitting through COP-data acquired from gear tooth surface determines the helical gear’s primary features. Particle swarm optimization algorithm as an efficient method is applied to perform the surface fitting process in this article.

Determination of Addendum Modification Coefficients for Spur Gears Operating at Non-Standard Center Distances

2003 ◽  
Author(s):  
M. A. Sahir Arikan
Keyword(s):  
Gear Tooth ◽  
Gear Ratio ◽  
Spur Gears ◽  
Contact Ratio ◽  
Performance Variables ◽  
Practical Design ◽  
Gear Drives ◽  
Maximum Contact ◽  
Center Distance

Although it is possible to find some recommended conventional values both for the sum of the addendum modification coefficients and for the allocation of the sum of the addendum modification coefficients (e.g. ISO/TR 4467), a detailed analysis is necessary to determine the addendum modification coefficient values for the desired optimization criteria and the performance since the main objective of the above mentioned sources is to facilitate practical design of non-standard gear drives which will not have problems while operating. They give practical average values within a safe range. In this study, by considering the required gear ratio, center distance and the desired backlash, alternative gear pairs are determined and corresponding gear performance variables are calculated in order to allocate the addendum modification coefficients for the pinion and the gear by using criteria such as: not having undercut or pointed (or excessively-thinned-tip) tooth, having desired proportions for the lengths of the dedendum and addendum portions of the line of action, having maximum contact ratio, having sufficient bottom clearance, having minimum contact stresses, having balanced pinion and gear tooth root stresses, having equal pinion and gear lives, etc.

A Method for Determining the AGMA Tooth Form Factor from Equations for the Generated Tooth Root Fillet

1986 ◽  
Vol 108 (2) ◽  
pp. 270-279 ◽  
Author(s):  
M. A. Lopez ◽  
R. T. Wheway
Keyword(s):  
Form Factor ◽  
Iterative Procedure ◽  
Gear Tooth ◽  
Critical Section ◽  
Tooth Root ◽  
Bending Stress ◽  
Tooth Form ◽  
Computer Generation ◽  
Tooth Section

The determination of the AGMA tooth form factor requires that the dimensions of the critical tooth section, at which the maximum bending stress is deemed to occur, be found. Critical section dimensions have traditionally been measured from a scaled generated layout of the tooth profile. The layout procedure, however, requires very careful drafting, and even then it is difficult to achieve really satisfactory accuracy because of the complex operations required to produce the fillet curve, with the added difficulty of estimating the point of tangency with the Lewis iso-bending stress parabola. Although a number of analytical methods are available for computing the critical section dimensions, their solution has generally been cumbersome, or convergence on the correct solution remained a problem. This paper presents equations for the gear tooth root fillet curve which have been derived from an analysis of the relative motion between a rack cutter and gear tooth during the generating cycle. An improved iterative procedure is used to find the critical tooth section dimensions from these equations. A further application of the root fillet equations, which is also covered, is in the computer generation of tooth profiles for assessment of the final tooth shape.

On the Invariance of Gear Tooth Curvature

2006 ◽  
Vol 220 (7) ◽  
pp. 1083-1096 ◽  
Author(s):  
D B Dooner
Keyword(s):  
Gear Tooth ◽  
Helix Angle ◽  
Gear Pair ◽  
Principal Curvatures ◽  
Gear Teeth ◽  
Conical Gears ◽  
Tooth Type ◽  
Instantaneous Pressure ◽  
Principal Directions

A method is presented for the determination of the principal curvatures along with their principal directions of two gear teeth in direct contact. The procedure used to determine these extreme curvatures and directions is based on the nominal position of contact. Moreover, these extreme curvatures and directions are invariant with tooth type (viz. involute and cycloidal) and manufacturing process. Such curvatures and directions depend on the instantaneous pressure angle, spiral or helix angle, and position of contact. This generalized method is applicable to cylindrical gears (spur and helical), conical gears (straight and spiral), as well as hyperboloidal gears (hypoid and worm). Three examples are included to illustrate the determination of principal curvatures and directions. The first example is a helical gear pair, the second is a spiral bevel gear pair, and the third example is a hypoid gear pair.

scholarly journals Method of identification of parameters of closed planetary train based on exploratory design

2018 ◽  
Vol 224 ◽  
pp. 02020
Author(s):  
Ildar Kutlubaev ◽  
Elena Matcko ◽  
Olga Panfilova
Keyword(s):  
Gear Tooth ◽  
Minimum Weight ◽  
Functional Limitations ◽  
Geometric Parameters ◽  
Design Stage ◽  
Kinematic Scheme ◽  
Structural Scheme ◽  
Initial Design ◽  
Input And Output

Practicability of usage of gears with closed planetary trains in high-powered drives having weight and dimensions limitations is represented. Method that makes it possible to perform evaluation of mass-dimensional characteristics of planetary double-flow gears at the exploratory design stage is proposed. The developed approach makes it possible to determine basic geometric parameters of gear-tooth system: diameters and width of tooth-wheels reasonably. Besides the obligatory fulfillment of contact tooth strength conditions, providing of the required transmission ratio and condition of coincidence of axes of the gear input and output shafts, the condition of its minimum weight and dimensions is taken into account either. The last requirement is achieved by determination of conditional factor that is square of kinematic scheme contour expressed through projected parameters. The minimum value of contour square corresponds to the best combination of diameters and width values of tooth wheels if all functional limitations are maintained. Then the need of arbitrary choice of any of projected parameters and further verification of the choice made at the closing designing stage is excepted. The proposed approach makes it possible to evaluate the efficiency of chosen gear structural scheme at the initial design stage without design study of workpieces and units.

Determination of Principal Curvatures and Contact Ellipse for Profile Crowned Helical Gears

1999 ◽  
Vol 121 (1) ◽  
pp. 107-111 ◽  
Author(s):  
P.-H. Feng ◽  
F. L Litvin ◽  
D. P. Townsend ◽  
R. F. Handschuh
Keyword(s):  
Gear Tooth ◽  
Principal Curvatures ◽  
Helical Gears ◽  
Bearing Contact ◽  
Pinion Gear ◽  
Straight Line ◽  
Tooth Surfaces ◽  
Simplified Solution ◽  
Contact Ellipse

Helical gears with localized bearing contact of tooth surfaces achieved by profile crowning of tooth surfaces are considered. Profile crowning is provided by application of two imaginary rack-cutters with mismatched surfaces. The goal is to determine the dimensions and orientation of the instantaneous contact ellipse that requires the determination of principle curvatures of pinion-gear tooth surfaces. A simplified solution to this problem is proposed based on the approach developed in [1, 2] for correlation of principal curvatures and directions of generating and generated tooth surfaces. The obtained equations are applied for profile crowning where the normal profiles of the rack-cutters are either a circular arc or a straight line.

An Approach to the Determination of Spur Gear Tooth Root Fillet

2004 ◽  
Vol 126 (2) ◽  
pp. 336-340 ◽  
Author(s):  
V. B. Math ◽  
Satish Chand
Keyword(s):  
Gear Tooth ◽  
Spur Gear ◽  
Tooth Root ◽  
Base Circle ◽  
Point Of Intersection

The purpose of this paper is to present an approach for the determination of geometry of spur gear tooth root fillet. An equation is developed to determine the point of tangency of involute profile and root fillet on the base circle for a spur gear without undercutting and the point of intersection of root fillet and involute profile above the base circle for an undercut gear. Generation using a hob or rack type cutter with protuberance (increase in tooth thickness at the tip of the hob tooth) is also discussed.

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