This paper describes a new type of valve gear cam—MULTICAM—which consists of seven curves and allows an optimum cam profile design. In order to calculate the cinematic and dynamic values and to assess the minimum oil film thickness in the valve gear, the mathematical model of an ideal valve gear was used. In addition, the comparison of the results between the polysine cam and the new MULTICAM cam design was made. By means of the new cam design the Hertz pressures were reduced at the point of contact between the cam and the cam follower and the lubrication properties at the top of the cam improved.

Issue Section:
Technical Papers
Keywords:
valves, design engineering, lubrication, internal combustion engines
Topics:
Gears, Valves, Design, Lubrication
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Copyright © 2002
 by ASME
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