Mini roller arrangement for valve train mechanism

In a valve train mechanism of an internal combustion engine having a cylinder head, a camshaft supported for rotation in said engine, a valve mounted in said cylinder head for movement between an open position and a closed position, said valve having a valve stem and being provided with a spring for biasing said valve into said closed position, a rocker arm located between said camshaft and said valve, said rocker arm having the intermediate portion thereof supported by said cylinder head for pivotal movement and having one end engaging the upper end of said valve stem, the other end of said rocker arm being provided with at least a pair of side-by-side cavities each of which takes the form of a concave bearing surface, a shaftless roller located in each of said cavities, said camshaft having a cam-lobe for initially engaging only one of the rollers and subsequently engaging the next adjacent roller so as to provide a valve lifting force to rollers to cause said rocker arm to pivot and act through said one end of said rocker arm to move said valve to said open position against the bias of said spring.

In a valve train mechanism of an internal combustion engine having a cylinder head, a camshaft supported for rotation in said engine, a valve mounted in said cylinder head for movement between an open position and a closed position, said valve being provided with a spring for biasing said valve into said closed position, a finger follower located between said camshaft and said valve, said finger follower having one end thereof supported by said cylinder head for pivotal movement and having the other end actuating said valve, at least a pair of cavities formed in said finger follower intermediate said one end and said other end, a shaftless roller located in each of said cavities for rotation relative thereto, said camshaft having a cam-lobe initially engaging said one of said shaftless rollers and subsequently engaging the next adjacent shaftless roller so as to provide a valve lifting force to said finger follower to cause the latter to pivot and act through said other end of said finger follower to move said valve to said open position against the bias of said spring.

In a valve train mechanism of an internal combustion engine having a cylinder head, a camshaft having cam-lobe and being supported for rotation in said engine, a valve mounted in said cylinder head for movement between an open position and a closed position, said valve being provided with a spring for biasing said valve into said closed position, an inverted bucket tappet having its top surface provided with a disk member and being located between said camshaft and said valve, said cam-lobe of said camshaft cooperating with said disk member to apply a lifting force to move said valve to said open position against the bias of said spring during rotation of said camshaft, the improvement wherein said disk member is provided with at least a pair of concave bearing surfaces each of which is provided with a shaftless mini-roller, the arrangement being such that said cam-lobe of said camshaft initially contacts one of said mini-rollers after which said cam-lobe contacts the next adjacent mini-roller during rotation of said camshaft so as to transmit said lifting force from said camshaft to said valve.