Rocker arm and hydraulic lash adjuster with load/motion control button

Claim 1

An integral rocker arm and hydraulic lash adjuster with load/motion control button assembly including a rocker arm having a cam actuated arm portion, an intermediate support portion with a cylindrical bore extending transversely therethrough whereby the rocker arm is adapted to be pivotably supported about a pivot axis and supplied with pressurized oil and an opposed valve actuator arm to control the opening and closing movement of a valve via a valve stem thereof, said valve actuator arm having a stepped bore therethrough and a slot means extending through said stepped bore at a right angle to said pivot axis and having a width so as to slidably receive the valve stem, said stepped bore defining, in succession starting from a lower end, a cylindrical enlarged lower wall defining a cavity, an adjuster guide wall, anenlarged intermediate wall and a further enlarged upper wall with a retainer groove therein, an abutment shoulder connecting said adjuster guide wall and said intermediate wall and a second abutment shoulder connecting said intermediate wall and said retainer groove in said upper wall; a disc retainer positioned in said intermediate wall and defining therewith a reservoir adapted to be supplied with oil under pressure; a split ring retainer operatively positioned in said retainer groove to secure said disc retainer aganist axial movement in one direction; a hydraulic lash adjuster including a cylindrical follower body having a closed end slidably received in said adjuster guide wall and a plunger operatively positioned within said follower body to abut at one end aganist said disc retainer, said closed end of said follower body having an actuator depending coaxial therefrom a predetermined axial extent with said actuator having a semi-roundish shaped outer peripheral surface configuration; and, a load/motion control button loosely positioned and retained within said cavity defined by said lower wall, said load/motion control button having a socket on one side thereof operatively engaging said semi-roundish shaped actuator in substantially rolling contact therewith, the opposite surface of said load/motion control button being flat for abutment against the valve stem, the arrangement being such that an effective working radius R 1 of said valve actuator arm and an included angle between the reciprocating axis of said valve and R 1 is less than 90° at the valve closed position and must not exceed 90° at the valve open position whereby during pivotal movement of the rocker arm said load/motion control button will exhibit no or reduced scrub across said valve stem.