Design of Gerotor Using Cycloid and Circular-Arc Curves

사이클로이드 및 원호 곡선을 이용한 제로터 개발

  • Choi, Tae-Hoon (School of Mechanical Engineering, Pusan Nat'l Univ.) ;
  • Kim, Moon-Saeng (School of Mechanical Engineering, Pusan Nat'l Univ.) ;
  • Lee, Geun-Su (Research Institute, Samhan Co., Ltd) ;
  • Jung, Sung-Yuen (Research Institute of Mechanical Technology, Pusan Nat'l Univ.) ;
  • Kim, Chul (Research Institute of Mechanical Technology, Pusan Nat'l Univ.)
  • 최태훈 (부산대학교 기계공학부) ;
  • 김문생 (부산대학교 기계공학부) ;
  • 이근수 ((주)삼한 연구소) ;
  • 정성윤 (부산대학교 기계기술연구원) ;
  • 김철 (부산대학교 기계기술연구원)
  • Received : 2010.08.17
  • Accepted : 2010.12.24
  • Published : 2011.03.01


The new gerotor developed in this paper has an inner rotor in which a circular arc is inserted between the hypocycloid and epicycloid curves, whereas the outer rotor is designed using the simulation results for the rotor and a modification method. The new gerotor has no cusps and loops and no limit on the eccentricity. We increase the average flow rate by adding a new design parameter, $\gamma$, which is the inclined angle of the inner rotor at the intersection of the hypocycloid and the circular arc. A calculation method to calculate the chamber area is also developed. This method can also be used to calculate the flow rate and flow rate irregularity when the contact points are unknown. The control of eccentricity and $\gamma$ is expected to lead to an efficient rotor.


Circular Arc;Cycloid;Eccentricity;Flow Rate;Gerotor


Supported by : 한국산업기술진흥원


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