Load Sharing in Metallic and Non-Metallic Gears

Walton, D.; Tessema, Addis; Hooke, C. J.; Shippen, James

doi:10.1243/pime_proc_1994_208_104_02

Cited by 33 publications

(25 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In reference [15] the author included the gear body in his analysis, thereby reducing gear stiffness and compared the pitch point stiffness of gear pairs as determined by different authors. FE methods have been used for the analyses of polymer gears by Walton et al [16], who examined load sharing. As a result the real contact ratio as distinct from the ideal or theoretical contact ratio for spur gears was determined and plotted using a non-dimensional approach in which the real contact ratio was uniquely defined in terms of the gear geometry, torque and elastic modulus, termed the non-dimensional gear elasticity parameter.…”

Section: Gear Deformationsmentioning

confidence: 99%

Minimization of transmission errors in highly loaded plastic gear trains

Meuleman¹,

Walton

Dearn

et al. 2007

Proceedings of the Institution of Mechanical Engineers, Part C:

Self Cite

View full text Add to dashboard Cite

Transmission errors (TEs) are an important source of unwanted noise and vibration in gear drives. Errors can result from geometrical inaccuracies and from elastic deformations. Plastic drives are often loaded in a way that produces high deflections relative to steel gears, and the elastic component of TE is relatively more important. Furthermore, plastic gears are often run in mesh with gears made from steel or other metals. In this case there is a large difference in tooth stiffness, which leads to unusual TE problems. The current paper discusses the origins of elastic TEs and means of their calculation. A simple beam model is used to demonstrate the stiffness of a pair of meshing gear teeth. A finite-element analysis is used to refine this model and to run iterative tooth meshing enabling TEs to be accurately characterized. A number of TE traces from gear pairs running under high loads are included and compared with the theoretical predictions. Several different scenarios are proposed including balancing gear tooth stiffness for dissimilar materials and the adjustment of pressure angle to account for tooth deflection. A set of design guidelines are presented in the conclusions. A case study of a precision printer drive is used to illustrate some of the techniques for the minimization of TEs.As load increases, the effect of tooth stiffness becomes more important.TE is the prime source of vibration in geared systems and is thus important in any noise or vibration study and is particularly important when attempting to minimize noise. In some motion control mechanisms TE can lead to positional inaccuracy -for example it can lead to image distortion in high quality printing transports.This paper considers the effects of material stiffness and tooth geometry on the TEs of polymer gears running in polymer/polymer and polymer/steel combinations. In the former case, the arguments in fact apply to any pairing of materials with similar stiffnesses, whereas the latter applies to any material pairing with large differences (greater than one order of magnitude) in stiffness. In each case, the stiffness of a gear pair is considered, design modifications are proposed and performance improvements demonstrated. JMES439

show abstract

Section: Gear Deformationsmentioning

confidence: 99%

Minimization of transmission errors in highly loaded plastic gear trains

Meuleman¹,

Walton

Dearn

et al. 2007

Proceedings of the Institution of Mechanical Engineers, Part C:

Self Cite

View full text Add to dashboard Cite

show abstract

“…Due to the large de�ections in polymer gears, real load sharing (and hence the real contact ratio) will be quite different to theoretical predictions [13]. Walton et al [14] suggested that the most severe conditions are likely to occur at the pitch point (which will be the same value for both theoretical and real conditions and so are representative of the most severe conditions).…”

Section: Elastohydrodynamic Lubricationmentioning

confidence: 94%

“…Note that in all the efficiency �gures shown in this paper, oil churning and spindle/bearing losses have been subtracted. Figure 7(b) shows the derived coefficients of friction calculated from the measured efficiencies and by using (14). While the coefficients of friction show the dependency of load, the curves are relatively �at with respect to speed.…”

Section: Experimental Programmementioning

confidence: 99%

Lubrication Regimes in High-Performance Polymer Spur Gears

Dearn

Hoskins

Andrei

et al. 2013

Advances in Tribology

View full text Add to dashboard Cite

Little has been published on the behaviour of polymer gears operating under lubricated conditions. An experimental and analytical programme was undertaken to classify the regimes of EHL under which polymer spur gears operate. In doing so theoretical �lm thicknesses were calculated and then used to classify the regime according to Johnson's Map. e effects of lubrication on the operating efficiencies of high-performance polymer gears were interpreted and from these results coefficients of friction were derived. In addition to this the effect of tooth geometry was investigated and the bene�cial in�uence of high-pressure angle tooth geometry is demonstrated. At loads typically associated with polymer gears the operating regime is shown to be mixed �lm lubrication. �hen high-pressure angle gears were tested at high loads the operating regime became full �lm lubrication and relatively little tooth �ank damage occurred.

show abstract

“…The interference on the gear tooth profile after the last point of contact can be calculated as tip interference, Tf, and flank interference, Fi,. A finite element procedure has been adopted to calculate the deflection of gear teeth under load (14). In this work the authors were able to show that the real contact ratio, cR, could be expressed in terms of a non- @ IMcchE 1995 dimensional gear elasticity parameter, T = T/(rb bmE), and the ideal contact ratio, E, (Fig.…”

Section: Calculation Of Tip and Flank Interference By The Finite Elemmentioning

confidence: 96%

A Note on Tip Relief and Backlash Allowances in Non-Metallic Gears

Walton

Tessema

Hooke

et al. 1995

Proceedings of the Institution of Mechanical Engineers, Part C:

Self Cite

View full text Add to dashboard Cite

Previous work on load sharing in non-metallic gears indicated that the change in operating contact ratio is large enough to cause concern. Tests also show that premature contact between the gear teeth can lead to severejank wear. This paper shows that predetermined amounts of tip relief are needed to minimize this form of wear from occurring. The tip relief suggested in this paper is compared to recommendations given in the British Standard. Finally, for non-metallic gears, allowances for backlash due to elastic deformation of the teeth are suggested.

show abstract

Load Sharing in Metallic and Non-Metallic Gears

Cited by 33 publications

References 16 publications

Minimization of transmission errors in highly loaded plastic gear trains

Minimization of transmission errors in highly loaded plastic gear trains

Lubrication Regimes in High-Performance Polymer Spur Gears

A Note on Tip Relief and Backlash Allowances in Non-Metallic Gears

Contact Info

Product

Resources

About