Development of Rotor for Internal Gear Pump using Cycloid and Polycircular-arc Curves

사이클로이드 및 폴리서클 곡선을 이용한 내접형 기어펌프용 치형 개발

  • Kim, Min-Soo (Creative Engineering System, Pusan National Univ.) ;
  • Lee, Hyun-Woo (Creative Engineering System, Pusan National Univ.) ;
  • Jung, Sung-Yuen (Research Institute of Mechanical Technology, Pusan National Univ.) ;
  • Kim, Chul (Research Institute of Mechanical Technology, Pusan National Univ.)
  • 김민수 (부산대학교 창의공학시스템) ;
  • 이현우 (부산대학교 창의공학시스템) ;
  • 정성윤 (부산대학교 기계기술연구원) ;
  • 김철 (부산대학교 기계기술연구원)
  • Received : 2012.03.21
  • Accepted : 2012.06.20
  • Published : 2012.09.01


A new type of gerotor developed in this paper has the inner rotor designed by inserting a polycircular-arc between the hypocycloid and epicycloid curves, and we also suggest that the outer rotor be designed using the closed-form equation for the inner rotor and a method of modification. Thus, it is possible to design a gerotor for which there is no cusp and loop, as in this case undercut is prevented. We developed automated program for rotor design and calculation of the flow rate and flow rate irregularity. And we also demonstrate the superior performance of the gerotor developed in this study by analyzing the internal fluid flow using a commercial computation fluid dynamics-code (CFD).


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