A switching roller finger follower comprises an inner arm assembly. A pair of outer arms surround the inner arm assembly. A pivot axle connects the inner arm assembly to pivot with respect to the pair of outer arms from a starting position to a lost motion position. A latch assembly comprises a latch selectively movable from a latched position latching the inner arm assembly to move dependent with the outer arms and an unlatched position unlatching the inner arm assembly to pivot independent of the outer arms. A stop pin spans between the pair of outer arms and through an inner port in an axle of inner arm assembly. The stop pin comprises a clearance fit with the inner port, and the stop pin is configured pivotable independent of the outer arms. At least one return spring biases the stop pin toward the starting position.

A switching roller finger follower comprises an inner arm assembly. A pair of outer arms surround the inner arm assembly. A pivot axle connects the inner arm assembly to pivot with respect to the pair of outer arms from a starting position to a lost motion position. A latch assembly comprises a latch selectively movable from a latched position latching the inner arm assembly to move dependent with the outer arms and an unlatched position unlatching the inner arm assembly to pivot independent of the outer arms. A stop pin spans between the pair of outer arms and through an inner port in an axle of inner arm assembly. The stop pin comprises a clearance fit with the inner port, and the stop pin is configured pivotable independent of the outer arms. At least one return spring biases the stop pin toward the starting position.

An engine valve actuation system includes engine braking rocker arms each having a hydraulically actuated switch, and an electrohydraulic control system including an actuation fluid supply, an electrically actuated valve adjustable to vary a pressure of actuation fluid supplied from the actuation fluid supply to the hydraulically actuated switches, and an engine braking control unit. The engine braking control unit is structured to command adjusting the electrically actuated valve to adjust the hydraulically actuated switch in each of the engine braking rocker arms at a switching window timing that is varied from engine braking cycle to engine braking cycle to distribute hard handoffs among the engine braking rocker arms.

A valve actuation system comprises at least one main rocker arm operatively connected to a first engine valve, the at least one main rocker arm configured to receive at least main valve actuation motions. A second rocker arm is operatively connected to a second engine valve, the second rocker arm being configured to receive first auxiliary valve actuation motions. The second rocker arm further comprising a hydraulically-controlled first actuator that can selectively couple or decouple the second rocker arm and the second engine valve thereby permitting or preventing conveyance of the first auxiliary valve actuation motions from the second rocker arm to the second engine valve. A one-way coupling mechanism disposed between the at least one main rocker arm and the second rocker arm permits valve actuation motions to be transferred from the at least one main rocker arm to the second rocker arm, but not vice versa.

An oil supply carrier assembly configured to be mounted to a valve train carrier having a plurality of rocker arms according to the present disclosure includes an oil supply carrier housing having a first oil inlet port and a second oil inlet port. The oil supply carrier housing supports an oil control valve and further includes first, second and third oil supply passages. The first oil supply passage is configured to deliver oil from the first oil inlet port on the valve train carrier to the oil control valve. The second oil supply passage is configured to deliver oil from the valve train carrier to at least one engine brake rocker arm of the rocker arms. The third oil supply passage is configured therein to deliver oil from the second oil inlet port to the rocker arms.

Systems and methods for operating an engine with deactivating and non-deactivating valves are presented. In one example, valves of a cylinder are deactivated in a closed state in response to an indication of degradation of a valve of the cylinder. Further, fuel flow to the cylinder may be stopped via ceasing to inject fuel to the cylinder.

A valve actuation system includes a rocker for conveying motion to an engine valve, a motion source arranged to impart motion to the rocker, rocker stop assembly configured to operate in an activated mode, in which the rocker stop assembly maintains the rocker in a position corresponding to partial valve lift, and a deactivated mode, in which the rocker stop assembly allows the rocker to move to a position corresponding to a fully closed valve position, and a rocker stop reset assembly for resetting the rocker stop assembly to the deactivated mode subsequent to a main event peak lift to thereby achieve late valve closing. A damper assembly may interact with the rocker stop assembly to provide a smooth transition of the rocker and valve motion to a late intake valve closing dwell. A valve catch assembly may control the seating velocity of the at least one valve.

A compression release type engine brake includes a first opening unit and a second opening unit each including an exhaust rocker arm, an adjusting screw provided at an end portion of the exhaust rocker arm, a brake module in which brake oil is selectively and a brake piston mount portion is formed therein, a brake piston which is selectively protruded according to the oil supply inside the brake module, a reset member selectively exhausting the oil in the brake module, and a valve bridge connected to the brake piston and provided with an exhaust valve, and wherein a rocker arm protrusion is formed in the exhaust rocker arm of at least one of the first opening unit and the second opening unit, and the shaft spring presses the rocker arm protrusion and adjusts a distance between the first opening unit and the second opening unit.

A roller hydraulic valve lifter includes a body having a longitudinal central axis and an interior area defined by an inside surface which has a pair of flat surfaces opposite one another and connected by a pair of walls. A first bore, essentially perpendicular to the longitudinal axis, extends through the flat surfaces. A bearing is disposed partially in the interior area. The bearing includes an outer ring having substantially cylindrical exterior and interior bearing surfaces. A shaft extends through the first bore and the outer ring and between the pair of flat surfaces. A plurality of needle rollers is disposed between and rollingly engage the shaft and the cylindrical inner bearing surface. The shaft and the plurality of needle rollers are manufactured from an AISI 52100 alloy steel that is carbo-nitrided. The shaft and the plurality of needle rollers have a surface hardness of a minimum of HRc 65.

A valvetrain for an internal combustion engine includes a camshaft, an electromagnetic latch assembly, a rocker shaft, and a rocker arm assembly. The rocker arm assembly may include a cam follower configured to engage a cam mounted on the camshaft as the camshaft rotates and a rocker arm configured to rotate on the rocker shaft. The electromagnetic latch assembly may include a pin translatable between a first position and a second position and an electromagnet that causes the pin to actuate. The movement of the pin may provide mode switching for a switching rocker arm, a cylinder deactivating rocker arm, or an engine brake rocker arm. The electromagnet is powered by a circuit that passes through the rocker shaft. The electromagnet may be mounted to the rocker shaft. Running the circuit through the rocker shaft allows the electromagnet to be powered with wiring that remains stationary.