Theoretical and experimental evaluation of tappet rotation for a direct acting valve train system
by M.-R. Cho, H.-J. Kim, T.-S. Moon, D.-C. Han
International Journal of Vehicle Design (IJVD), Vol. 34, No. 1, 2004

Abstract: This study discusses an analytical model for evaluating and measuring the tappet rotational speed of the direct acting valve train system. To calculate the tappet rotational speed, the load transferred to the cam and the tappet is calculated using dynamic analysis of a single valve system. The friction against the cam and tappet is calculated using mixed lubrication theory while considering the both of oil film and friction between tappet and tappet bore at the same time. A dynamic equation is developed for the rotational and translational motion of tappet within the tappet bore, and the solution of the equation obtained using numerical method. We have developed a rotational speed signal monitoring system using a laser and optical fibre to measure the tappet rotational speed. To measure the tappet rotational speed, the system uses on/off signals from the encoder and a photo transistor attached under the tappet. We discuss several analyses and experiments executed under various operating conditions and compare to each other. Analytical and experimental results are generally coincided with each other. The rotational speed of the tappet tends to increase with eccentricity and temperature of the supplied oil. Also it tends to increase with the cam rotational speed as well. This study shows also that tappet rotation reduces the friction loss between the cam and the tappet.

Online publication date: Mon, 10-May-2004

The full text of this article is only available to individual subscribers or to users at subscribing institutions.

 
Existing subscribers:
Go to Inderscience Online Journals to access the Full Text of this article.

Pay per view:
If you are not a subscriber and you just want to read the full contents of this article, buy online access here.

Complimentary Subscribers, Editors or Members of the Editorial Board of the International Journal of Vehicle Design (IJVD):
Login with your Inderscience username and password:

Username:        Password:          Forgotten your password?

Want to subscribe?
A subscription gives you complete access to all articles in the current issue, as well as to all articles in the previous three years (where applicable). See our Orders page to subscribe.

If you still need assistance, please email subs@inderscience.com