A latch assembly comprises a latch pin and a cage. The latch pin comprises a latch nose and a pin body. The pin body comprises an outer surface and an inner compartment. The inner compartment comprises a first inner wall segmented by a first slot and a second inner wall segmented by a second slot. The first slot and the second slot vent out of the inner compartment. The cage comprises a stepped base and a shaft extending from the stepped base into the inner compartment. The shaft comprises a first exterior flat adjoining the first inner wall and a second exterior flat adjoining the second inner wall. A spring can be biased against the latch pin and the cage. The latch assembly can be used in a latching device of a valvetrain such as a switching roller finger follower or other rocker arm.

A hydraulic lash assembly (HLA) for use in a valvetrain. The HLA preferably includes a first arm configured to transition a valve between a closed orientation and an open orientation. The first arm can include an engagement surface to receive a driving force from a timing member and to cause the valve to transition to the open orientation for a predetermined period. The HLA further preferably includes a second arm to receive a holding force from an actuator and a pivot section to couple to the first arm and displace the first arm based on the holding force from the actuator. Preferably, the first arm and the second arm form a lever arrangement whereby the pivot section of the second arm underlies and supports the first arm and allows for rotational movement of the first arm that is independent from the second arm.

A lift regulator for a variable lift valve gear has a cam contour arranged around an axis of rotation of the lift regulator for deflecting a lift adjustment of the valve gear on rotation of the lift regulator about the axis of rotation. The cam contour has a region deflecting from a resting position, a changeover region, and a region deflecting back to the resting position. A variable lift valve gear and a method for operating the variable lift valve gear are disclosed.

A rocker arm assembly for pivoting around a rocker shaft comprises a follower side arm, a valve side arm, and a latch assembly. The follower side arm comprises a main body (1016, 2016, 3016), a rocker shaft through-bore (1061), and a follower end (11, 21, 31) comprising a latch through-bore (1019, 2019, 3019). The valve side arm comprises a forked body (1026, 2026) and a valve end (12,22) extending from the forked body. A first arm extension (1025, 2025, 3025) and a second arm extension (1028, 2028, 3028) extend from the forked body and straddle the main body. A first distal end (1125, 2125) comprises a first latch pocket (51) distal from the forked body. A second distal end (1128, 2128) comprises a second latch pocket (81) distal from the forked body. The latch through-bore selectively aligns with the first latch pocket and the second latch pocket.

A system for selectively activating and deactivating cylinders includes a first cylinder positioned in a cylinder block. A first intake or exhaust valve is coupled to the first cylinder and is actuated by a first coupling mechanism. A first oil control solenoid is coupled to the first coupling mechanism, the first oil control solenoid deactivates the first coupling mechanism to maintain the first intake or exhaust valve in a closed position. A second cylinder is positioned in the cylinder block, and a second intake or exhaust valve is coupled to the second cylinder. The second intake or exhaust valve is actuated by a second coupling mechanism. A second oil control solenoid is coupled to the second coupling mechanism, the second oil control solenoid deactivates the second coupling mechanism to maintain the second intake or exhaust valve in a closed position. The first oil control solenoid and the second oil control solenoid have different operating parameters.

Systems, devices, and methods are disclosed that during cylinder deactivation, including skipfire, at low engines speeds and low engine loads maintain adequate oil pressure of valvetrain components or hardware required for CDA and/or skipfire operation.

An internal combustion engine system includes an engine with a plurality of pistons housed in respective ones of a plurality of cylinders, an air intake system to provide air to the plurality of cylinders through respective ones of a plurality of intake valves, an exhaust system to release exhaust gas from the plurality of cylinders through respective one of a plurality of exhaust valves. A valve train is provided for cylinder deactivation of a first part of the plurality of cylinders and compression release braking on a second part of the plurality of cylinders.

Methods and systems are provided for actuating an advanced cam profile switch (CPS) assembly. In one example, a system may include a first cylinder and a second cylinder of the CPS assembly that may be independently coupleable to a valve stem via two separate locking mechanisms. A first cam may be selectively engage with the first cylinder and the valve stem and a second cam may be selectively engaged with the second cylinder and the valve stem.

Systems and methods to extend a life of a component of a cylinder deactivation system are provided. A method includes generating, by a controller, an initial life factor for the component; initiating, by the controller, a CDA mode for an engine; determining, by the controller, an actual life factor for the component, the actual life factor determined by comparing a number of switching events of a cylinder in the CDA mode to a number of cycles of the cylinder in the CDA mode; comparing, by the controller, the actual life factor to the initial life factor; and modifying, by the controller based on the comparison, operation of the engine in the CDA mode to adjust the actual life factor.

Systems and methods for mitigating exhaust gas emissions via cylinder deactivation are provided. A system includes a controller coupled to an internal combustion engine and an electric motive device. The controller includes a processor and a memory coupled to the processor. The memory stores instruction that, when executed by the processor, cause the controller to: command the internal combustion engine to operate in a cylinder deactivation mode whereby at least one cylinder of a plurality of cylinders of the internal combustion engine is deactivated; receive a power request exceeding a current power output from the internal combustion engine; command the electric motive device to provide a supplemental power output based on the received power request; and, subsequent to commanding the electric motive device to provide the supplemental power out, activate the at least one cylinder of the plurality of cylinders of the internal combustion engine.