An Experimental Study on the Tappet Spin for a Direct Acting Valve Train System

직접 구동형 밸브 트레인 시스템의 태핏 회전에 관한 실험적 연구

  • 조명래 (현대자동차 파워트레인 연구소) ;
  • 김형준 (현대자동차 파워트레인 연구소) ;
  • 문태선 (서울대학교 대학원 기계항공공학부) ;
  • 한동철 (서울대학교 기계항공공학부)
  • Published : 2003.07.01


The technique for measuring the rotational speed of tappet in direct acting type valve train system has been developed. The optic signal monitoring system with laser and optic fiber was designed to follow the signal of tappet rotation. The system was based on ON/OFF signal generation from the additional encoder teeth under the tappet with optic fibers attached photo transistor. The data showed that tappet rotation was affected by offset, oil temperature and cam shaft operating speed. Also it was found that tappet rotation increases with oil temperature. Tappet spin was delayed 10∼s20$^{\circ}$ cam angle after valve opening. The instantaneous rotational speed of tappet was reciprocal to cam shaft speed and the tappet and the cam angle ratio was located in the range of 0.1∼0.3.


Valve Train;Tappet;Rotational Speed;Laser;Encoder;Optic fiber;Photo Transistor


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