Optimum design on the lobe shapes of Gerotor Oil Pump

제로터 오일 펌프 로버형상에 관한 최적설계

  • 김재훈 (부산대학교 정밀정형및금형가공연구소) ;
  • 김창호 (동의대학교 기계공학과) ;
  • 김철 (부산대학교 기계기술연구소)
  • Published : 2006.04.01

Abstract

A gerotor pump is suitable for oil hydraulics of machine tools, automotive engines, compressors, constructions and other various applications. Especially the pump is an essential machine element of an automotive engine to feed lubricant oil. The subject of this paper is the theoretical analysis of internal lobe pump whose the main components are the rotors: usually the outer one is characterized by lobes with circular shape, while the inner rotor profile is determined as conjugate to the other. For this reason the first topic presented here is the definition of the geometry of the rotors starting from the design parameters. The choice of these parameters is subject to some limitations in odor to limit the pressure angle between the rotors. Now we will consider the design optimization. The first step is the determination of the instantaneous flow rate as a function of the design parameter. This allows us to calculate three performance indexes commonly used far the study of positive displacement pumps: the flow rate irregularity, the specific flow rate, and the specific slipping. These indexes are used to optimize the design of the pump and to obtain the sets of optimum design parameter. Results obtained from the analysis enable the designer and manufacturer of oil pump to be more efficient in this field, and the system could serve as a valuable one for experts and as a dependable training aid for beginners.

References

  1. Colbourne, J. R., 'Gear Shape and Theoretical Flow Rate in Internal Gear Pumps,' Transactions of the CSME, Vol. 3, No.4, pp. 215-223, 1975
  2. Saegusa, Y., Urashima, K., Sugimoto, M., Onoda, M. and Koiso, T., 'Development of Oil-Pump Rotors with a Trochoidal Tooth Shape,' SAE Paper No. 840454
  3. Tsay, C. B. and Yu, C. Y., 'Mathematical Model for the Profile of Gerotor Pumps,' J. CSME, Vol. 10, No.1, pp. 41-47, 1989
  4. Yu, C. Y. and Tsay, C. B., 'The Mathematical Model of Gerotor Pump Applicable to Its Characteristic Study,' J. CSME, Vol. 11, No.4, pp. 385-391, 1990
  5. Lee, S. C., Lee, S. N., 'Design and Analysis of Gerotor for Hydraulic Motors,' Journal of KSTLE, Vol. 11, No.2, pp. 63-70, 1995
  6. Kim C. H., Kim D. I., Ahn, H. S., Chong, T. H., 'Analysis of Tooth Contact Stress of Gerotor Hydraulic Motors,' Journal of KSTLE, Vol. 15, No.2, pp. 164-170, 1999
  7. Kim, J. H., Kim, Chul, 'Development of an Integrated System of Automated Design of Gerotor Oil Pump,' J. of The Korean society of precision engineering, Vol. 23, No.2, pp. 88-96, 2006