An Experimental Study on The Friction Coefficient of Rubbers for Clutch Master Cylinder Cup-Seals

클러치 마스터실린더 컵-시일 고무의 마찰계수 실험 연구

  • 이재천 (계명대학교 기계자동차공학부) ;
  • 임문혁 (계명대학교 기계자동차공학부) ;
  • 이병수 (계명대학교 기계자동차공학부) ;
  • 장지현 (계명대학교 기계공학 대학원) ;
  • 정용승 (계명대학교 기계공학 대학원) ;
  • 허만대 ((주)평화발레오) ;
  • 최병기 ((주)평화발레오)
  • Published : 2003.09.01


The friction coefficients of the rubber for clutch master cylinder were experimentally measured in this study. The cylindrical rubber samples for primary cup-seal and secondary cup-seal were tested against the aluminum or the steel plates of master cylinder housing under the various conditions of brake oil temperatures and normal loads. Dry sliding friction coefficients were also measured under various load conditions. The test revealed following results. First, the friction coefficient under fluid lubrication condition in general decreases, as the oil temperature or normal load increases. Second, the steel plate of low surface roughness yielded comparatively low friction coefficient on the range of 0.30∼0.67. On the other hand, the aluminum plate of high surface roughness yielded high friction coefficient on the range of 0.31∼1.15. Third, the friction coefficient of dry surface contact decreases as the normal load increases. This is contrary to the general principle of friction coefficient between metal plates.


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