Abstract: A lock pin bore in a two-step rocker arm assembly contains a hydraulically-actuable lock pin. A return spring urges the lock pin toward an unlatched mode. The bore has one or more annular grooves formed near the outer end of the bore. A plug, formed preferably of a soft metal, is pressed as a hydraulic seal into the bore. During assembly, the final position of the lock pin within the bore is set by positioning a stopping assembly fixture into the locking end of the bore. The plug is pressed into the bore until contact is made with the lock pin and the lock pin engages the fixture. The plug is radially deformed into the annular groove(s) to anchor the plug and fix the outer limit of travel of the locking pin and the compressive load on the return spring.

Abstract: An apparatus for adjusting individual valve lift comprising a control arm assembly disposed between the cam lobes and the valve rockers for a multi-valve train. The control arm at each valve includes a driven gear. An actuator shaft includes a mating drive gear at each driven gear for rotating each control arm to vary the overall lift of the valves. In the prior art, the mating drive gears are fixed to the actuator shaft at identical fixed orientations. In accordance with the present invention, each mating drive gear is rotatably adjustable on the actuator shaft to permit changing of the orientation of each gear with respect to the actuator shaft, thereby changing the contact point of the control arm with its respective cam lobe. The lifts of the individual valves may be individually adjusted to provide equal air flow through all the valves in a multi-valve train.

Abstract: A two-step roller finger follower having a high-lift follower portion that pivots on a pivot shaft disposed on a low-lift follower portion, and having a lost-motion spring disposed between the high-lift follower and the low-lift follower to bias the high-lift follower toward the high lift cam lobe. Various bearing cups and roller shaft sleeve embodiments are shown, all of which allow for improved shaft and needle bearing arrangements. A z-stop formed by the bearing cups and/or the shaft sleeve limits the range of travel of the high-lift follower with respect to the low-lift follower. Various z-stop embodiments are provided including a non-contacting roller shaft sleeve that grounds the high-lift follower to the low-lift follower independent of the roller shaft.

Abstract: A bearing design for a roller finger follower assembly includes an outer arm having a pair of openings, a shaft extending across the outer arm through the openings, a pair of lateral follower rollers mounted at opposite ends of the shaft; and a pair of bearings rotatably supporting the lateral follower rollers. The shaft is not a member of the bearing. Therefore, a force acting on the rollers travels through the rollers directly into the bearing and into the outer arm which reduces the potential for the rollers to become detached from the shaft. An inboard bearing design involves an inner bearing race integrated into the rollers. An outboard bearing design involves an inner bearing race integrated in the outer arm and an outer bearing race integrated into the rollers.

Abstract: A two-step roller finger follower having a high-lift follower portion that pivots on a pivot shaft disposed on a low-lift follower portion, and having a lost-motion spring disposed between the high-lift follower and the low-lift follower to bias the high-lift follower toward the high lift cam lobe. Various bearing cups and roller shaft sleeve embodiments are shown, all of which allow for improved shaft and needle bearing arrangements. A z-stop formed by the bearing cups and/or the shaft sleeve limits the range of travel of the high-lift follower with respect to the low-lift follower. Various z-stop embodiments are provided including a non-contacting roller shaft sleeve that grounds the high-lift follower to the low-lift follower independent of the roller shaft.

Abstract: A lock pin bore in a two-step rocker arm assembly contains a hydraulically-actuable lock pin. A return spring urges the lock pin toward an unlatched mode. The bore has one or more annular grooves formed near the outer end of the bore. A plug, formed preferably of a soft metal, is pressed as a hydraulic seal into the bore. During assembly, the final position of the lock pin within the bore is set by positioning a stopping assembly fixture into the locking end of the bore. The plug is pressed into the bore until contact is made with the lock pin and the lock pin engages the fixture. The plug is radially deformed into the annular groove(s) to anchor the plug and fix the outer limit of travel of the locking pin and the compressive load on the return spring.

Abstract: An improved pin housing sub-assembly configured for reliable assembly and stability as an intermediate sub-assembly. The length of the plunger return spring is greater than the diameter of the spring well in the pin housing, such that the spring cannot be accidentally installed sideways in the well. During assembly, the non-compressed longer spring places the pushrod seat flush with the end of the pin housing. A shallow annular groove is provided in the inner wall of the pin housing near the outer end thereof, and an expansion ring may be installed therein when the plunger return spring is slightly compressed. The expansion ring holds the sub-assembly together as an intermediate but is displaced by the spring tower in a subsequent assembly step to become the locking ring between the pin housing and the spring tower, as in the prior art.

Abstract: A valve-deactivation hydraulic valve lifter including a conventional hydraulic lash adjuster means disposed within a pin housing slidably disposed in a lifter body. A transverse bore in the pin housing contains opposed locking pins for selectively engaging a circumferential groove including a locking surface in the lifter body whereby the lifter body and the pin housing may be engaged or disengaged to activate or deactivate a pushrod controlling an engine valve. Ends of the locking pins are spherical so that the pins cannot become stuck in corners in the groove. The groove corner is rounded be either a positive radius or a negative radius to remove a sharp corner known to be an originating and propagating point for stress failure of the lifter body in prior art lifters. The edge of each pin and the edge of the locking surface are chamfered to prevent damage to these edges during locking and unlocking. A second surface intermediate an outer surface of the pin housing and the transverse bore is also provided.

Abstract: A valve-deactivation hydraulic valve lifter including a conventional hydraulic lash adjuster means disposed within a pin housing slidably disposed in a lifter body. A transverse bore in the pin housing contains opposed locking pins for selectively engaging a circumferential groove including a locking surface in the lifter body whereby the lifter body and the pin housing may be engaged or disengaged to activate or deactivate a pushrod controlling an engine valve. Ends of the locking pins are spherical so that the pins cannot become stuck in corners in the groove. The groove corner is rounded be either a positive radius or a negative radius to remove a sharp corner known to be an originating and propagating point for stress failure of the lifter body in prior art lifters. The edge of each pin and the edge of the locking surface are chamfered to prevent damage to these edges during locking and unlocking. A second surface intermediate an outer surface of the pin housing and the transverse bore is also provided.

Abstract: A deactivation hydraulic valve lifter includes an elongate lifter body having a substantially cylindrical inner wall. The inner wall defines at least one annular pin chamber therein. The lifter body has a first end configured for engaging a cam of an engine. An elongate pin housing includes a substantially cylindrical pin housing wall and pin housing bottom. The pin housing wall includes an inner surface and an outer surface. The pin housing bottom defines a radially directed pin bore therethrough. The pin housing is concentrically disposed within the inner wall of the lifter body such that the outer surface of the pin housing wall is adjacent to at least a portion of the inner wall of the lifter body. A plunger having a substantially cylindrical plunger wall with an inner surface and an outer surface is concentrically disposed within the pin housing such that the outer surface of the plunger wall is adjacent to at least a portion of the inner surface of the pin housing wall.

Abstract: A deactivation hydraulic valve lifter includes an elongate lifter body having a substantially cylindrical inner wall. The inner wall defines at least one annular pin chamber therein. The lifter body has a first end configured for engaging a cam of an engine. An elongate pin housing includes a substantially cylindrical pin housing wall and pin housing bottom. The pin housing wall includes an inner surface and an outer surface. The pin housing bottom defines a radially directed pin bore therethrough. The pin housing is concentrically disposed within the inner wall of the lifter body such that the outer surface of the pin housing wall is adjacent to at least a portion of the inner wall of the lifter body. A plunger having a substantially cylindrical plunger wall with an inner surface and an outer surface is concentrically disposed within the pin housing such that the outer surface of the plunger wall is adjacent to at least a portion of the inner surface of the pin housing wall.

Abstract: A hydraulic lash adjuster for disposition between a rocker arm and a valve stem of an internal combustion engine comprises a body having an axially extending neck depending from a lower end thereof. An enlarged head portion extends from the terminal end of the neck and has a semispherical lower surface. A foot assembly includes a disk shaped foot with an upper surface, a lower surface and a cylindrical sidewall defining an outer perimeter. The upper surface has a socket configured to receive the enlarged head. The foot assembly further includes an inverted cup shaped retainer having a cylindrical wall and radial leaves extending inwardly from the upper end of the cylindrical wall, defining a central opening. The axially extending neck extends through the central opening and the opening has a diameter smaller than the enlarged head.