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US 4,382,428 AGranted
Contoured finger follower variable valve timing mechanism
OwnerEdward M. Tourtelot, Jr.inventor
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OwnerEdward M. Tourtelot, Jr.inventor
Estimating the term…
A mechanism for varying the timing of the valves of an internal combustion engine wherein an elongated finger follower for each of the intake and/or each of the exhaust valves of the engine is disposed between and movable while engaged with the cams for the respective valves and linkage means that extends between the valves and the finger followers. The proximal ends of the followers are pivotally connected to the swingable ends of a plurality of cranks, the opposite ends of the cranks being connected to a control shaft that is mounted for limited rotational movement about an axis adjacent and parallel to the axis of rotation of the engine camshaft. Each finger follower has a convex surface engageable with the actuating linkage for its associated valve and a concave control surface engageable with the cam associated with a particular valve. The control surface includes contiguous portions of decreasing and increasing radius which coact with the opening and closing flank portions of the cam associated therewith to vary the timing of the valve in accordance with the position of the follower. The decreasing and increasing radius portions of the control surface are free of discontinuities so that the finger follower can shift between its limit positions without subjecting the components of the valve train to undesirable acceleration rates or shocks.
Mechanism for varying the time at which a valve for controlling the flow of fluid into or out of a combustion chamber of an internal combustion engine opens and closes, said combustion chamber being defined by a cylinder in the engine and a piston movable in the cylinder for varying the volume thereof, said engine also including a rotatable crankshaft and a rotatable camshaft driven in timed relation with the speed of said crankshaft and linkage means for transmitting reciprocating movement to said valve, and said mechanism comprising a cam member on said camshaft and contoured to provide a predetermined timing for said valve such as will provide optimum performance and efficiency of said engine throughout one operating speed range, follower means engageable with said cam member and said linkage means for varying said predetermined timing of said valve, said follower means having a control surface engaging said cam member and another surface adapted to engage said linkage means, said control and other surfaces each including first and second contiguous, curved portions, and operating means connected to said follower means for shifting the latter throughout a range of positions such as to vary said predetermined timing while said control surface is engaged with said cam member and said other surface is engaged with said linkage means.
Dependencies are inferred from the claim text.