Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
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Contact Surface Fatigue Life for RPG System

RPG 시스템의 접촉 피로수명

  • Nam, Hyoung-Chul (Graduate School, Dept. of Mechanical Design and Manufacturing, Changwon Nat'l Univ.) ;
  • Kwon, Soon-Man (Dept. of Mechanical Design and Manufacturing, Changwon Nat'l Univ.) ;
  • Shin, Joong-Ho (Dept. of Mechanical Design and Manufacturing, Changwon Nat'l Univ.)
  • 남형철 (창원대학교 대학원 기계설계공학과) ;
  • 권순만 (창원대학교 기계설계공학과) ;
  • 신중호 (창원대학교 기계설계공학과)
  • Received : 2011.06.07
  • Accepted : 2011.07.28
  • Published : 2011.11.01
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Abstract

A roller pinion gear (RPG) system composed of either a pin or a roller and its conjugated cam gear can improve the gear endurance from that of a conventional gear system by reducing the sliding contact while increasing the rolling motion. In this paper, we first proposed the exact cam gear profile and the self-intersection condition obtained when the profile shift coefficient is introduced. Then, we investigated the Hertzian contact stresses and the load stress factors while the varying the shape design parameters to predict the gear surface fatigue life, which is strongly related to the gear noise and vibration at the contact patch. The results show that the pitting life can be extended significantly by increasing the profile shift coefficient.

외접기어의 어느 한쪽 기어를 핀 또는 롤러로 대체한 롤러 피니언 기어 (RPG) 시스템은 기어 치물림 시 미끄럼 접촉을 줄이고 구름운동을 증대시켜 기어 내구성을 향상시킬 수 있다. 우선 본 논문에서는 전위계수(profile shift coefficient)를 고려하여 RPG 시스템의 캠 기어(cam gear)의 엄밀 치형설계 방법 및 치 꼬임으로 인한 간섭 방지조건을 제시하였다. 또 기어구동에 있어 치면에서 발생되는 진동이나 소음의 원인이 되는 피팅(pitting) 발생수명을 고려하기 위해, 설계인자의 변화에 따른 Hertz 접촉응력 및 하중응력계수(load stress factor)의 변화를 검토하였다. 이를 통해 RPG 시스템의 내구성을 향상시킬 수 있는 방안으로 전위계수의 증가를 제안하였다.

Keywords

References

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