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

The Korean Society of Mechanical Engineers (대한기계학회)
권호 표지
DOI QR코드

DOI QR Code

Pitting Life for RRP System

RRP 시스템의 피팅수명

  • Kim, Chang-Hyun (Dept. of Mechanical Design & Manufacturing Engineering, Changwon Nat'l Univ.) ;
  • Nam, Hyung-Chul (Dept. of Mechanical Design & Manufacturing Engineering, Changwon Nat'l Univ.) ;
  • Kwon, Soon-Man (Dept. of Mechanical Design & Manufacturing Engineering, Changwon Nat'l Univ.)
  • 김창현 (창원대학교 기계설계공학과) ;
  • 남형철 (창원대학교 기계설계공학과) ;
  • 권순만 (창원대학교 기계설계공학과)
  • Received : 2011.06.23
  • Accepted : 2012.02.07
  • Published : 2012.04.01
Download PDF
⟨ Previous Next ⟩

Abstract

A roller rack pinion (RRP) system, which consists of a rack-bar and a cam pinion, transforms a rotation motion into a linear one. The rack-bar has a series of roller trains, and meshes with the cam pinion. This paper first proposes the exact tooth profile of the cam pinion and the non-undercut condition to satisfy the required performance by introducing the profile shift coefficient. The paper then investigates the load stress factors under various shape design parameters to predict the gear surface fatigue limit, which was strongly related to the gear noise and vibration at the contact patch. The results show that the pitting life can be extended significantly with an increase in the profile shift coefficient.

본 논문에서는 기존 랙-피니언 시스템의 랙 치형을 핀 또는 롤러로 대체한 롤러 랙 피니언 (RRP) 시스템의 표면피로 향상방안을 고찰하였다. 우선 전위계수(profile shift coefficient)를 고려하여 RRP 시스템의 캠 피니언(cam pinion)에 대한 엄밀 치형설계 방법 및 언더컷 방지 조건을 소개하였고, 이를 바탕으로 설계인자의 변화에 따른 하중 및 하중응력계수(load stress factor)의 변화를 검토하였다. 이를 통해 RRP 시스템의 표면 내구성을 향상시킬 수 있는 방안으로 전위계수의 증가가 효과적임을 알 수 있었다.

Keywords

References

  1. Gonzalez-Palacios, M. A. and Angeles, J., 2003, "The Design of a Novel Pure-Rolling Transmission to Convert Rotational into Translational Motion," Trans. ASME, Jornal of Mechanism Design, Vol. 125, pp. 205-207. https://doi.org/10.1115/1.1531850
  2. Chablat, D. and Angeles, J., 2005, "Strategies for the Design of a Slide-O-Cam Transmission," International Workshop on Computational Kinematics, Cassino May 4-6.
  3. Ham, S. H., Nam, W. K. and Oh, S. H., 2010, "A Study on Optimum Tooth Profile of Pin-Pinion Gear for Linear Motion," KSPSE, Vol. 14, No. 3, pp. 64-70.
  4. Ikejo, K., Nagamura., K., Tanaka, E. and Yamamoto, K., 2008, "Driving Performance and Strength of Pin-Rack Gear Mechanism," Journal of Japan Society for Design Engineering, Vol. 43, No. 7, pp. 388-394.
  5. Nagamura, K., Ikejo, K., Tanaka, E. and Yamamoto, K., 2008, "Driving Performance of Pin-Rack Gear Mechanism Using a Trochoid Tooth Profile," The Machine Design and Tribology Division Meeting in JSME, 2008-04-20, pp. 205-208.
  6. Morrison, R. A., 1968, "Load/Life Curves for Gear and Cam Materials," Machine Design, Vol. 40, pp. 102-108.
  7. Litvin, F. L., 1994, Gear Geometry and Applied Theory, PTR Prentice Hall, Englewood Cliffs.
  8. Kwon, S.-M., Nam, H. C., Lu, L. and Shin, J.-H., 2009, "A Study on Optimal Wear Design for a Gerotor Pump," Transactions of the KSME, Series A, Vol. 33, No. 1, pp. 82-88. https://doi.org/10.3795/KSME-A.2009.33.1.82
  9. Kwon, S.-M., Sim, M. Y., Nam, H. C. and Shin, J.-H., 2009, "Optimal Wear Design for a Hypotrochoidal Gear Pump without Hydrodynamic Effect," Transactions of the KSME, Series A, Vol. 33, No. 12, pp. 1383-1392. https://doi.org/10.3795/KSME-A.2009.33.12.1383