Abstract: A rocker arm includes an outer arm having a first wall and a second wall and an inner arm which selectively pivots relative to the outer arm about a pivot shaft axis of a pivot shaft based on positioning of a lock pin. A lost motion spring includes an outer arm tang grounded to the outer arm and an inner arm tang grounded to the inner arm. A roller shaft is supported by the inner arm and extends toward the first wall. The roller shaft carries a roller which follows a camshaft. A roller retainer is carried by the roller shaft and is located between the roller and the first wall and includes a surface with which the inner arm tang is engaged to ground the lost motion spring to the inner arm, a roller shaft aperture containing the roller shaft, and a pivot shaft aperture containing the pivot shaft.

Abstract: In a dual intake valve arrangement for an internal combustion engine, a variable valve lift system controls two intake valves for one or more engine cylinders. In each cylinder, one of the intake valves includes an associated two-step actuation device, and the other includes an associated valve deactivation device. To improve in-cylinder air flow turbulence, one valve may be operated in a high-lift or low-lift state while the other valve may be deactivated.

Abstract: In a dual intake valve arrangement for an internal combustion engine, a continuously variable valve lift (CVVL) system controls two intake valves for one or more engine cylinders. In each cylinder, one of the intake valves includes an associated valve deactivation device, and the other intake valve does not. To improve in-cylinder air flow turbulence under low valve lift, one of the intake valves may be deactivated, resulting in mixture intake through only one valve, resulting in strong swirl by unbalanced flow. A CVVL-equipped engine including a valve deactivation device provides the same amount of air flow for the same engine load as a prior art CVVL engine. A method of introducing a swirl to the mixture is also described.

Abstract: In a dual intake valve arrangement for an internal combustion engine, a variable valve lift system controls two intake valves for one or more engine cylinders. In each cylinder, one of the intake valves includes an associated two-step actuation device, and the other includes an associated valve deactivation device. To improve in-cylinder air flow turbulence, one valve may be operated in a high-lift or low-lift state while the other valve may be deactivated.

Abstract: A two-step roller finger follower assembly for use in conjunction with a camshaft of an internal combustion engine, wherein the camshaft has at least one first lobe and at least one second lobe. The roller finger follower assembly comprises a follower body for engaging the first cam lobe and having a central aperture, a follower pivotably disposed on the follower body in the central aperture for engaging the second cam lobe, and a limiting stop disposed on the follower body for engaging a feature on the follower to limit travel of the follower body with respect to the follower. The limiting stop prevents overtravel of the follower body during valve-deactivation mode of the assembly, thus preventing excessive leak down of an associated hydraulic lash adjuster.

Abstract: In a dual intake valve arrangement for an internal combustion engine, a continuously variable valve lift (CVVL) system controls two intake valves for one or more engine cylinders. In each cylinder, one of the intake valves includes an associated valve deactivation device, and the other intake valve does not. To improve in-cylinder air flow turbulence under low valve lift, one of the intake valves may be deactivated, resulting in mixture intake through only one valve, resulting in strong swirl by unbalanced flow. A CVVL-equipped engine including a valve deactivation device provides the same amount of air flow for the same engine load as a prior art CVVL engine. A method of introducing a swirl to the mixture is also described.

Abstract: A two-step roller finger follower assembly for use in conjunction with a camshaft of an internal combustion engine, wherein the camshaft has at least one first lobe and at least one second lobe. The roller finger follower assembly comprises a follower body for engaging the first cam lobe and having a central aperture, a follower pivotably disposed on the follower body in the central aperture for engaging the second cam lobe, and a limiting stop disposed on the follower body for engaging a feature on the follower to limit travel of the follower body with respect to the follower. The limiting stop prevents overtravel of the follower body during valve-deactivation mode of the assembly, thus preventing excessive leak down of an associated hydraulic lash adjuster.

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: An electromechanical VVA system for controlling the poppet valves in the cylinder head of an internal combustion engine. The system varies valve lift, duration, and phasing in a dependent manner for one or more banks of engine valves. A rocker subassembly for each valve or valve pair is pivotably disposed on a control shaft between the camshaft and the roller finger follower. The control shaft may be displaced about a pivot axis outside the control shaft to change the angular relationship of the rocker subassembly to the camshaft, thus changing the valve opening, closing, and lift. A plurality of control shafts for controlling all valvetrains in an engine bank defines a control shaft assembly. The angular positions of the individual control shafts may be tuned to optimize the valve timing of each cylinder. The system is applicable to the intake and exhaust camshafts of diesel and gasoline engines.

Abstract: An anti-rotation guide for preventing rotation of a roller follower valve lifter in an internal combustion engine. The guide has an outer surface for engaging an engine bore and an inner surface for slidably receiving the lifter. One end of the guide includes an anti-rotation feature for cooperating with a mating feature on the lifter, preferably flats although other configurations are contemplated within the scope of the invention. The anti-rotation feature may take any of a plurality of shapes, including but not limited to an arm and tang, a flap, and an orifice flat. The guide is installed from an opening in the engine bore proximate a camshaft disposed in the engine block. The cooperating features prevent axial rotation of a lifter within the sleeve but do not inhibit axial or reciprocal motion of the lifter.

Abstract: A variable valve actuation mechanism includes a control shaft assembly and a body. The control shaft assembly is pivotable relative to a pivot axis. The body is pivotally disposed on the control shaft assembly, and includes an input cam follower and at least one output cam surface. The input cam follower engages an input cam lobe, and the output cam surface engages a corresponding output cam follower. A spring engages the body and biases the input cam follower into engagement with the input cam lobe.

Abstract: A variable valve actuation mechanism includes a control shaft assembly and a body. The control shaft assembly is pivotable relative to a pivot axis. The body is pivotally disposed on the control shaft assembly, and includes an input cam follower and at least one output cam surface. The input cam follower engages an input cam lobe, and the output cam surface engages a corresponding output cam follower. A spring engages the body and biases the input cam follower into engagement with the input cam lobe.

Abstract: An anti-rotation guide for preventing rotation of a roller follower valve lifter in an internal combustion engine. The guide has an outer surface for engaging an engine bore and an inner surface for slidably receiving the lifter. One end of the guide includes an anti-rotation feature for cooperating with a mating feature on the lifter, preferably flats although other configurations are contemplated within the scope of the invention. The anti-rotation feature may take any of a plurality of shapes, including but not limited to an arm and tang, a flap, and an orifice flat. The guide is installed from an opening in the engine bore proximate a camshaft disposed in the engine block. The cooperating features prevent axial rotation of a lifter within the sleeve but do not inhibit axial or reciprocal motion of the lifter.