Abstract: A variable valve actuator assembly includes a main actuator, a secondary actuator and an actuator shaft. The actuator shaft is coupled to each of the main actuator and the secondary actuator. The main actuator and the secondary actuator are each separately and independently selectable for driving the actuator shaft to rotate.

Abstract: A variable valve actuator assembly includes a main actuator, a secondary actuator and an actuator shaft. The actuator shaft is coupled to each of the main actuator and the secondary actuator. The main actuator and the secondary actuator are each separately and independently selectable for driving the actuator shaft to rotate.

Abstract: Variable valve timing (VVT) mechanisms are disclosed which are relatively compact and are applicable for operating individual or multiple valves. In an exemplary embodiment, dual engine valves are driven by an oscillatable rocker cam that is actuated by a linkage driven by a rotary cam. The linkage is pivoted on a control member that is in turn pivotable about the axis of the rotary cam and angularly adjustable to vary the orientation of the rocker cam and thereby vary the valve lift and timing. The rotary cam is carried on a camshaft and the oscillatable rocker cam is pivoted on the rotational axis of the rotary cam. A control shaft connects with the control member through an angled slider and slot connection that provides a variable angular ratio for improved charge control at low valve lifts. A worm gear actuator may be applied to drive the control shaft.

Abstract: A camshaft has, for each valve lifter, a high lift cam between two low lift cams, the high lift cam fitting within the envelope of the low lift cams. The lifter comprises an outer tappet elongated in the direction of the camshaft and slidably mounted in an elongated bore in a cam carrier. The outer tappet is contacted by both low lift cams and operates two valves simultaneously. An elongated bore extending transverse of the outer tappet carries an elongated inner tappet which is contacted by the high lift cam. A hydraulically actuated locking mechanism couples the tappets for movement together for high lift operation and unlocks for low lift operation to allow the inner tappet to idle in the outer tappet.