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.

제로터(Gerotor) 오일펌프는 구조가 간단하고 1 회전당 토출량이 많기 때문에 소형화에 유리하며, 자동차의 엔진 윤활유 공급원 및 자동 변속기의 유압원으로 널리 사용되고 있다. 최근 자동차 산업에서는 연비향상 및 소음저감이 가장 중요한 문제로 대두되는데, 내접형 기어펌프 측면에서는 제로터의 치형설계 및 포트형상 설계를 통하여 이를 대처하고 있다. 이에 본 논문에서는 유량맥동이 매우 작은 값을 가지도록 조합된(타원 1-타원형 인벌루트-타원 2) 외부로브 형상에 대하여 치형의 기구학적 조건을 만족하는 식을 유도하여 내부로브 형상을 창출하였으며, 이에 대한 첨점 및 루프가 발생하지 않는 설계인자 범위를 결정하였다. 또한 설계인자의 변화가 치형의 형상 및 성능인자(유량, 유량맥동)에 미치는 영향을 파악하여 최적의 치형을 구하고자 하였다.


Supported by : 한국연구재단


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