Abstract: An improved hydraulic lash adjuster including a cup-shaped adjuster body, and a plunger assembly disposed within the adjuster body. The plunger assembly includes a stepped axial bore extending from a body inner end to a central oil passage opening onto a hemispherical pivot head. A check valve cartridge sub-assembly is disposed against the step, defining a low-pressure oil chamber in the axial bore. A lash adjustment spring is disposed against the cartridge sub-assembly in a high-pressure chamber formed between the sub-assembly and the adjuster body. The cartridge sub-assembly may be used in other hydraulic lash adjusters such as are incorporated in hydraulic valve lifters.

Abstract: A system for bringing an internal combustion engine to a stop at a predetermined angular position of an engine shaft, such as a crankshaft or a camshaft, with respect to the engine's valves. The optimum shaft stop position is the point wherein the fewest lifters are collapsed the least amount. Exemplary methods and apparatus include using the engine starter motor to jog the stopped engine to the desired position; using the engine alternator to impose a variable electromagnetic load on the engine to bring the engine to a stop at the desired position; using variable firing of cylinders to control the deceleration profile to bring the engine to a stop at the desired position; and providing one or more detents formed in the shaft and using a shaft follower to control the stop position of the shaft by engaging the follower into a detent.

Abstract: A lock-pin cartridge for a valve deactivation rocker arm assembly. The cartridge comprises a body having an axial bore having first and second ends, the second end having a closure and a passage therethrough. A piston assembly comprising a locking pin and a piston is disposed in the bore. The locking pin extends through the second end passage to provide latching and unlatching of rocker arm elements. The piston is spaced apart from the ends to define a hydraulic chamber and a spring chamber within the bore on opposite sides of the piston. A spring is disposed in the spring chamber for urging the piston assembly toward one of the first and second ends. The hydraulic chamber includes means for communicating with a supply of hydraulic fluid for actuating the piston assembly.

Abstract: A two-step roller finger follower including an elongate body having side walls defining coaxially disposed shaft orifices, a pallet end and a socket end interconnecting with the side walls to define a slider arm aperture, and a latch channel. The socket end is mountable to an hydraulic lash adjuster, and the pallet end is matable with a valve stem. A slider arm for engaging a high-lift cam lobe is disposed in the slider arm aperture and has a first end pivotably mounted to the pallet end of the body and the second end forming a slider tip for engaging an activation/deactivation latch. The latch is slidably disposed in the latch channel, and the latch has a nose section for selectively engaging the slider tip. A spool-shaped roller having first and second roller elements fixedly attached to the shaft is rotatably disposed in the shaft orifices, the roller being adapted to follow the surface motion of low-lift cam lobes.

Abstract: A lock-pin cartridge for a valve deactivation rocker arm assembly. The cartridge comprises a body having an axial bore having first and second ends, the second end having a closure and a passage therethrough. A piston assembly comprising a locking pin and a piston is disposed in the bore. The locking pin extends through the second end passage to provide latching and unlatching of rocker arm elements. The piston is spaced apart from the ends to define a hydraulic chamber and a spring chamber within the bore on opposite sides of the piston. A spring is disposed in the spring chamber for urging the piston assembly toward one of the first and second ends. The hydraulic chamber includes means for communicating with a supply of hydraulic fluid for actuating the piston assembly.

Abstract: A two-step finger follower rocker arm assembly including a follower body having a socket at a first end for engaging a hydraulic lash adjuster and a pad at an opposite end for engaging a valve stem. A passage through the follower body in the direction of actuation by an engine cam is slidingly receivable of a slider member for variably engaging a central high-lift lobe. A lost-motion spring urges the slider member into contact with the central lobe. A latch member driven by a piston selectively locks the slider member to the follower body, causing the follower to follow the motion of the central cam lobe. When the latch member is disengaged, the slider member slides within the follower body, allowing lateral rollers to follow lateral cam lobes. The lateral rollers may be supported on the body by a rotatable cross-shaft or a fixed cross-shaft, or by a pair of fixed stub shafts, or by a pair of fixed bearing races.

Abstract: A two-step finger follower rocker arm assembly including a follower body having a socket at a first end for engaging a hydraulic lash adjuster and a pad at an opposite end for engaging a valve stem. A passage through the follower body in the direction of actuation by an engine cam lobe is slidingly receivable of a slider member for variably engaging a central cam lobe, preferably a high-lift lobe. An elongate shaft extends through a transverse bore in the slider member and through a slotted passage in the slider member. In the follower body, the shaft is provided with bearings supporting first and second lateral roller followers on opposite sides of the body for variably engaging first and second preferably low-lift lateral cam lobes flanking the central cam lobe. A lost-motion spring urges the slider member into contact with the central lobe. A latch member driven by a piston selectively locks the slider member to the follower body such that the follower follows the motion of the central cam lobe.

Abstract: A two-step finger follower rocker arm assembly including a follower body having a socket at a first end for engaging a hydraulic lash adjuster and a pad at an opposite end for engaging a valve stem. A passage through the follower body in the direction of actuation by an engine cam lobe is slidingly receivable of a slider member for variably engaging a central cam lobe, preferably a high-lift lobe. An elongate shaft extends through a transverse bore in the slider member and through a slotted passage in the slider member. In the follower body, the shaft is provided with bearings supporting first and second lateral roller followers on opposite sides of the body for variably engaging first and second preferably low-lift lateral cam lobes flanking the central cam lobe. A lost-motion spring urges the slider member into contact with the central lobe. A latch member driven by a piston selectively locks the slider member to the follower body such that the follower follows the motion of the central cam lobe.

Abstract: A two-step finger follower rocker arm assembly including a follower body having a socket at a first end for engaging a hydraulic lash adjuster and a pad at an opposite end for engaging a valve stem. A passage through the follower body in the direction of actuation by an engine cam is slidingly receivable of a slider member for variably engaging a central high-lift lobe. A lost-motion spring urges the slider member into contact with the central lobe. A latch member driven by a piston selectively locks the slider member to the follower body, causing the follower to follow the motion of the central cam lobe. When the latch member is disengaged, the slider member slides within the follower body, allowing lateral rollers to follow lateral cam lobes. The lateral rollers may be supported on the body by a rotatable cross-shaft or a fixed cross-shaft, or by a pair of fixed stub shafts, or by a pair of fixed bearing races.

Abstract: A two-step finger follower rocker arm assembly including a follower body having a socket at a first end for engaging a hydraulic lash adjuster and a pad at an opposite end for engaging a valve stem. A passage through the follower body in the direction of actuation by an engine cam lobe is slidingly receivable of a slider member for variably engaging a central cam lobe, preferably a high-lift lobe. An elongate shaft extends through a transverse bore in the slider member and through a slotted passage in the slider member. In the follower body, the shaft is provided with bearings supporting first and second lateral roller followers on opposite sides of the body for variably engaging first and second preferably low-lift lateral cam lobes flanking the central cam lobe. A lost-motion spring urges the slider member into contact with the central lobe. A latch member driven by a piston selectively locks the slider member to the follower body such that the follower follows the motion of the central cam lobe.

Abstract: A two-step roller finger follower including an elongate body having side walls defining coaxially disposed shaft orifices, a pallet end and a socket end interconnecting with the side walls to define a slider arm aperture, and a latch channel. The socket end is mountable to an hydraulic lash adjuster, and the pallet end is matable with a valve stem. A slider arm for engaging a high-lift cam lobe is disposed in the slider arm aperture and has a first end pivotably mounted to the pallet end of the body and the second end forming a slider tip for engaging an activation/deactivation latch. The latch is slidably disposed in the latch channel, and the latch has a nose section for selectively engaging the slider tip. A spool-shaped roller having first and second roller elements fixedly attached to the shaft is rotatably disposed in the shaft orifices, the roller being adapted to follow the surface motion of low-lift cam lobes.

Abstract: A system for selectively switching the action of a valve in an internal combustion engine includes a roller finger follower having a frame and a disengageable roller. A two-part axial pin for the roller axle is spring-loaded to urge the pin axially of the roller axle to disengage the first part of the pin from the follower frame and simultaneously disengage the second part of the pin from the roller axle. Thus the roller becomes detached from the frame and the follower cannot actuate its designated valve. The roller and pins are retained within the frame by at least one torsion spring. The pins may be controllably reinserted into the sides of the roller and frame to reconnect the roller to the frame by any of various electromechanical and/or hydraulic means. When used in conjunction with a camshaft having high lift and low lift cam lobes, the deactivated follower will then actuate its designated valve according to the profile of the low lift lobes, which may be a no lift profile.

Abstract: A two-step roller finger follower includes an elongate body having a first side member and a second side member. A first end and a second end interconnect the first and second side members. The first and second side member define first and second pin orifices, respectively. A center roller is disposed between the first and second side members. The center roller defines a shaft orifice therethrough. A shaft extends through the shaft orifice. A first shaft end is disposed proximate the first side member, and the second shaft end is disposed proximate the second side member. The second shaft end defines a shaft bore therein. The first shaft end defines a pin chamber therein. The shaft bore being is substantially concentric with and intersects the pin chamber. A locking pin assembly is disposed partially within the shaft bore, the pin chamber and at least one of the pin orifices.

Abstract: A control system for variable activation of valves in an internal combustion engine. A solenoid is disposed on the outer surface of the valve cam cover to avoid exposure to the hot-oil environment within the valve activation chamber. The solenoid armature extends through the cam cover into the valve activation chamber. A bellcrank is mounted between the solenoid armature and the latching pin of a latchable cam finger follower such that energizing and de-energizing of the solenoid causes corresponding actuation and deactuation of the finger follower, which may be suitable for high-lift and low-lift activation. Preferably, the bellcrank is compliant such that when the solenoid is actuated during the lift portion of the valve cycle the pin is placed under compression so that the pin is subsequently actuated into latching position when the follower moves to the base circle portion of the valve cam.

Abstract: A roller finger follower. includes an elongate body having first and second opposing sides each having respective inside surfaces. First and second grooves are defined by the respective inside surfaces. A slider bracket includes a top plate having a top surface that is substantially perpendicular to the first and second sides. First and second projections are affixed to or integral with the top plate, and protrude therefrom in a generally parallel manner relative to the top surface. The first projection is slidably disposed within the first groove and the second projection is slidably disposed within the second groove. A locking pin assembly is carried by the slider bracket, and selectively couples and decouples the slider bracket to and from the body.

Abstract: A mechanical assist actuation bracket for use with a roller finger follower. The roller finger follower includes a locking pin assembly having a trigger pin. The mechanical assist actuation bracket includes a face configured for being affixed to the roller finger follower. An arm extends from the face. The arm is configured for translating an actuating arm of an actuating device associated with the roller finger follower in a direction toward and away from the trigger pin during pivotal movement of the roller finger follower.

Abstract: A mechanical assist actuation bracket for use with a roller finger follower. The roller finger follower includes a locking pin assembly having a trigger pin. The mechanical assist actuation bracket includes a face configured for being affixed to the roller finger follower. An arm extends from the face. The arm is configured for translating an actuating arm of an actuating device associated with the roller finger follower in a direction toward and away from the trigger pin during pivotal movement of the roller finger follower.

Abstract: A system for selectively switching the action of a valve in an internal combustion engine includes a roller finger follower having a frame and a disengageable roller. A two-part axial pin for the roller axle is spring-loaded to urge the pin axially of the roller axle to disengage the first part of the pin from the follower frame and simultaneously disengage the second part of the pin from the roller axle. Thus the roller becomes detached from the frame and the follower cannot actuate its designated valve. The roller and pins are retained within the frame by at least one torsion spring. The pins may be controllably reinserted into the sides of the roller and frame to reconnect the roller to the frame by any of various electromechanical and/or hydraulic means. When used in conjunction with a camshaft having high lift and low lift cam lobes, the deactivated follower will then actuate its designated valve according to the profile of the low lift lobes, which may be a no lift profile.

Abstract: A two-step roller finger follower includes an elongate body having a first side member and a second side member. A first end and a second end interconnect the first and second side members. The first and second side member define first and second pin orifices, respectively. A center roller is disposed between the first and second side members. The center roller defines a shaft orifice therethrough. A shaft extends through the shaft orifice. A first shaft end is disposed proximate the first side member, and the second shaft end is disposed proximate the second side member. The second shaft end defines a shaft bore therein. The first shaft end defines a pin chamber therein. The shaft bore being is substantially concentric with and intersects the pin chamber. A locking pin assembly is disposed partially within the shaft bore, the pin chamber and at least one of the pin orifices.

Abstract: An improved direct acting hydraulic valve lifter (DAHVL) has features including reduced dead oil storage with lower mass and faster filling, improved air venting, internal oil recirculation and targeted oil supply that combine to reduce the presence of air in the lifter. Foam filling and baffle reconfiguration are included among means for reducing stored oil volume which can also improve the follower cylinder support. Means for venting along the piston and cylinder of the lifter are shown. The various features combine to limit air intake and to more quickly expel air which does enter the lifter.