Optimal Design of Gerotor with Combined Lobe Profiles (Ellipse 1-Elliptical Involute-Ellipse 2)

타원 1-타원형 인벌루트-타원 2 로브 형상의 제로터 최적 설계

  • Kwak, Hyo Seo (Dept. of Creative Engineering, Pusan Nat'l Univ.) ;
  • Li, Sheng Huan (Dept. of Creative Engineering, Pusan Nat'l Univ.) ;
  • Kim, Chul (Research Institute of Mechanical Technology, Pusan Nat'l Univ.)
  • 곽효서 (부산대학교 창의공학시스템공학과) ;
  • 이승환 (부산대학교 창의공학시스템공학과) ;
  • 김철 (부산대학교 기계기술연구원)
  • Received : 2015.06.13
  • Accepted : 2015.10.06
  • Published : 2015.12.01


A gerotor can be manufactured in a miniature size because it has a high discharge per cycle and a simple structure. Gerotors are widely used for the lubrication oil of an engine and as the hydraulic source of an automatic transmission. Recently, improvements in fuel efficiency and noise reduction have come to the fore in the automobile industry, and it has been necessary for better fuel efficiency to continuously improve the flow rate and noise of internal gear pumps through the optimal design of the gerotor and port shape. In this study, gerotors were generated based on the equations derived for a lobe shape with multiple profiles (ellipse 1-elliptical involute-ellipse 2). The ranges of the design parameters were considered to prevent a cusp and loop. In addition, the optimal lobe shape was obtained by determining the influence of the lobe shape on the performances (flow rate, irregularity, etc.), according to the values of the design parameters.


Supported by : 한국연구재단


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