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http://dx.doi.org/10.3795/KSME-A.2003.27.7.1179

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

Cho, Myung-Rae (현대자동차 파워트레인 연구소)
Kim, Hyung-Jun (현대자동차 파워트레인 연구소)
Moon, Tae-Seon (서울대학교 대학원 기계항공공학부)
Han, Dong-Chul (서울대학교 기계항공공학부)
Publication Information
Transactions of the Korean Society of Mechanical Engineers A / v.27, no.7, 2003 , pp. 1179-1184 More about this Journal
Abstract
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.
Keywords
Valve Train; Tappet; Rotational Speed; Laser; Encoder; Optic fiber; Photo Transistor;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
연도 인용수 순위
1 Han, D. C. and Cho, M. R., 1998, 'The Characteristics of Friction in Direct Acting OHC Valve Train System,' J. of KSTLE, Vol. 14, No. 1, pp, 23-27   과학기술학회마을
2 Pisano, A. P., 1984, 'Coulomb Friction in High-Speed Cam System,' Transactions of ASME, Journal of Mechanisms, Transmissions, and Automation in Design, pp. 1-5
3 Staron, J. T. and Willermet, P. A., 1983, 'An Analysis of Valve Train Friction in Terms of Lubrication Principles,' SAE 830165
4 Crane, M. E. and Meyer, R. C., 1990, 'A Process to Predict Friction in an Automotive Valve Train,' SAE 901728
5 Willermet, P. A., Pieprzak, J. M. and Dailey, D. P., 1992, 'Tappet Rotation and Friction Reduction in a Center Pivot Rocker Arm Contact,' Transactions of ASME, J. of Tribology, Vol. 108, No. 3, pp. 478-488
6 Taylor, C. M., 1993, 'Engine Tribology,' Tribology Series 26, Elsevier Science Publishers
7 Monteil, G., Gallmann, A., Sioshansi, P. and Loges, P., 1996, 'Contribution of Nuclear Physics to Engine Design: Application of Surface Layer Activation to Tappet Rotation Measurements,' SAE960711, pp. 7-21
8 Willerrnet, P. A. and Pieprzak, J. M., 1989, 'Some Effects of Lubricant Composition and Tappet Rotation on Cam/Tappet Friction,' Transactions of ASME, J. of Tribology, Vol. 111, No.4, pp. 638-691
9 Pieprzak, J. M., Willerrnet, P. A. and Klassen, D., 1989, 'A Tappet Rotation Monitor Based on Light Reflectance - Development and Functional Testing,' SAE 890722