Study on Thickness of Oil Film Formed between Gear Teeth

Research Project

Project/Area Number	06452170
Research Category	Grant-in-Aid for General Scientific Research (B)
Allocation Type	Single-year Grants
Research Field	設計工学・機械要素・トライボロジー
Research Institution	Fukuyama University
Principal Investigator	NONISHI Toshiji (1995) Faculty of Engineering, Fukuyama University Associate Professor, 工学部, 助教授 (10237860) 寺内喜男 (1994) 福山大学, 工学部, 教授 (70034296)
Co-Investigator(Kenkyū-buntansha)	野西利次福山大学, 工学部, 助教授 (10237860)
Project Period (FY)	1994 – 1995
Project Status	Completed (Fiscal Year 1995)
Budget Amount *help	¥5,900,000 (Direct Cost: ¥5,900,000) Fiscal Year 1995: ¥1,900,000 (Direct Cost: ¥1,900,000) Fiscal Year 1994: ¥4,000,000 (Direct Cost: ¥4,000,000)
Keywords	Spur Gear / Oil Film Thickness / Optical Interference method / Elastohydrodynamic Lubrication / Oil Temperature Increase / 平歯車潤滑油膜厚さ / 非ニュートン流粘性理論 / スキーズ作用 / 振動発生機
Research Abstract	The thickness of the oil film formed between two meshing gear teeth can be calculated on the basis of the elastohydrodynamic lubrication (EHL) theory developed by Dowson. The calculation of the EHL film thickness between meshing gear teeth is based on isothermal and steady-state condition ; in reality, non-isothermal and transient conditions predominate. Thus it is necessary that the film thickness calculated by the EHL theory be compared with the measured value. In this study, the elastohydrodynamic oil films formed between a gear tooth and a sapphire plate wre measured by an optical interference method. The agreement between the calculated film thickness and the measured value is recognized under the condition of low velocity. For high velocity the agreement is not so good, with the measured values of film thickness being smaller than the theoretical values. The experimental results can be explained by the theoretical calculation of oil temperature increase, which takes account of the effect of viscous heating and the effect of Eyring viscosity.