Modified geometry of spur gear drives for compensation of shaft deflections
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One of the main problems when standard spur gears are in mesh is the appearance of edge contact on the gear tooth surfaces caused by misalignments. Those misalignments are caused partially by deflections of gear supporting shafts. As a result of an edge contact, a non-favorable condition of the bearing contact occurs, yielding high level of contact stresses. An intensive research and many practical solutions have been directed to modify the gear tooth surfaces in order to avoid edge contact. An innovative procedure is proposed here for: (1) determination of errors of alignment caused by shaft deflections, (2) compensation of predicted shaft deflections during generation of spur gears, and (3), obtaining a favorable function of transmission errors for the design load. A finite element model of a spur gear drive that comprises pinion and gear supporting shafts is used for the determination of errors of alignment along a cycle of meshing. Compensation of misalignments caused by shaft deflections in gear generation is then accomplished by modification of pinion tooth surfaces whereas the gear tooth surfaces are kept unmodified. Additional modifications of pinion tooth surfaces may be required for obtaining a favorable function of transmission errors. The effect of several misalignment compensations in the reduction of contact stresses has been investigated. Postprocessing of load intensity functions and loaded transmission errors is included. The developed approach is illustrated with numerical examples.
KeywordsGear geometry Tooth contact analysis Finite element analysis Loaded transmission errors Shaft deflections
The authors express their deep gratitude to the Spanish Ministry of Economy and Competitiveness (MINECO) for the financial support of research projects Refs. DPI2010-20388-C02-01 (financed jointly by FEDER), DPI2013-47702-C2-1, and DPI2013-47702-C2-2.
- 4.Bradley W (1973) How to design the noise out of gears. Mach Des 45(30):49Google Scholar
- 5.Welbourn DB (1979) Fundamental knowledge of gear noise: a survey. In: Proceedings of noise and vibration of engines and transmissions, Inst Mech Eng, Cranfield, UK, pp 9–14Google Scholar
- 6.Drago RJ (1980) How to design quiet transmissions. Mach Des 52(28):175–181Google Scholar
- 7.Wildhaber E (1962) Method and machine for producing crowned teeth. United States Patent Office, Patent No 3,046,844Google Scholar
- 8.Novikov ML (1956) USSR Patent No 109,750Google Scholar
- 11.Litvin FL, Gonzalez-Perez I, Fuentes A, Hayasaka K, Yukishima K (2005) Topology of modified surfaces of involute helical gears with line contact developed for improvement of bearing contact, reduction of transmission errors, and stress analysis. Math Comput Modell 42(9–10):1063–1078MATHCrossRefGoogle Scholar
- 13.Roda-Casanova V, Iserte-Vilar JL, Sanchez-Marin FT, Fuentes A, Gonzalez-Perez I (2011) Development and comparison of shaft-gear models for the computation of gear misalignments due to power transmission. In: Proceedings of the ASME 2011 international design engineering technical conferences, Washington, DCGoogle Scholar
- 14.Gonzalez-Perez I, Roda-Casanova V, Fuentes A, Sanchez-Marin FT, Iserte JL (2012) A finite element model for consideration of the torsional effect on the bearing contact of gear drives. J Mech Des 134(071007):1–8Google Scholar
- 15.Gonzalez-Perez I, Fuentes A, Roda-Casanova V, Sanchez-Marin FT, Iserte JL (2013) A finite element model for stress analysis of lightweight spur gear drives based on thin-webbed and thin-rimmed gears. In: Proceedings of the VDI international conference on gears, MunichGoogle Scholar