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.

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 castellation assembly comprises a lost motion spring assembly, an upper castellation piece, and a lower castellation piece. A spring hat comprises a crown, a pin hole through the crown, and a brim. A lost motion spring is seated against the spring hat. Upper castellation piece comprises a tubular body, an upper inner rim adjoining the brim, and upper castellation teeth. Lower castellation piece comprises a spring post extending up from a castellation body, the spring post passing through the lost motion spring, and through the pin hole. Lower castellation teeth extend from the castellation body. The lost motion spring is biased against the castellation body to lift the upper inner rim by the brim. A lash screw can house the spring post so that the spring post terminates inside the lash screw. A rocker arm is an example of a castellation assembly installation.

A valve mechanism system in a hydraulic rocker arm (1) for a combustion engine comprises a check valve spring (2) and a check valve ball (3). Said spring (2) is arranged to be in contact with the check valve ball (3) and said spring (2) and ball (3) are arranged in a seat (4) in a recess (5) in the rocker arm (1). The recess (5) has a first opening (6) to a rocker arm channel (7) connected to a hydraulic element and a second opening (8) to a rocker arm oil supply via a second channel (9). The system further comprises a control piston (10) having a first end with a pin (11) axially aligned with the control piston (10) arranged in contact with said check valve ball (3) on the opposite side of the check valve ball (3) from the check valve spring (2). The check valve ball (3) is movable between a first position allowing oil to flow to and from the oil supply and a second position stopping oil from flowing between the two channels (7, 9). A control piston spring (12) is arranged on a second end of the control piston (10) such that it biases the control piston (10) towards the check valve ball (3). The control piston (10) in an axial direction is movably arranged in a cylinder shaped cartridge (13) and the cartridge has a first end arranged towards the outside of the rocker arm (1) and a second end in the axial direction opposite inner end. The cartridge is arranged in said recess (5) in the rocker arm (1).

A rocker assembly for a type III center pivot valvetrain comprises a rocker arm having a cam end, a center pivot bore, and a valve end which includes a first actuator bore and a second actuator bore. The rocker assembly further comprises a cylinder deactivation actuator arranged in the first actuator bore. The cylinder deactivation actuator comprises a hydraulically actuated latch assembly configured to selectively switch between a latched configuration and an unlatched configuration and a mechanical lash-setting sleeve distanced from a travel stop defined within the first actuator bore. The cylinder deactivation actuator further comprises a latch step disposed below the mechanical lash-setting sleeve and extending into the first actuator bore. The hydraulically actuated latch assembly is configured to selectively travel between the travel stop and the latch step when the hydraulically actuated latch assembly is in the latched configuration.

A rocker arm mechanism includes a rocker arm shaft, a rocker arm, a valve clearance adjuster, a valve train, and a control valve. The rocker arm is rotatably disposed on the rocker arm shaft. The valve train includes a valve bridge. The rocker arm is provided with a plunger chamber. The valve clearance adjuster includes a hydraulic tappet slidably disposed in the plunger chamber. The plunger chamber is supplied with oil through an oil supply passage. The control valve is configured to open or close the oil supply passage. When the control valve opens the oil supply passage, the hydraulic tappet can abut against the valve bridge and eliminate the clearance between the valve bridge and the hydraulic tappet.

A valve drive for an internal combustion engine, including a gas exchange valve; a first mechanically driven drive mechanism; and a second drive mechanism connected to the gas exchange valve to move same. The first and second drive mechanisms connected via a hydraulic coupling device that has a pressure chamber, which can be relieved of pressure via a valve device and is designed to couple the drive mechanisms by hydraulic pressure and to decouple same in a pressure-relieved state. The valve device has two switch valves fluidically connected to the pressure chamber in parallel and via which the pressure chamber is relieved of pressure in the open state of at least one of the switch valves. The valve drive has a controller that actuates the switch valves in a delayed manner to provide a variable valve stroke of the gas exchange valve during a stroke movement.

A valve train assembly includes an intake rocker arm, an exhaust rocker arm, a carrier configured to couple to a cylinder block and operably associated with the intake rocker arm and the exhaust rocker arm, the carrier including a first aperture, and a cylinder deactivation (CDA) capsule disposed within the first aperture. The CDA capsule is configured to move between a latched condition that transfers motion from a push rod to one of the intake rocker arm and the exhaust rocker arm, and an unlatched condition that absorbs motion from the push rod and does not transfer the motion to the intake rocker arm or the exhaust rocker arm.

A valve drive of an internal combustion engine may include a camshaft, at least one cam follower, at least one adjusting device, and a hydraulic actuating element. The camshaft may include at least one first cam structured as a brake cam and a second cam structured as an exhaust cam. The at least one first cam may have a reduced cam lift relative to the second cam. The at least one cam follower may be connected to an exhaust valve of the internal combustion engine via a rocker. The hydraulic actuating element may be adjustable to an extended position and a retracted position. In the extended position, the hydraulic actuating element may be operatively connected to the brake cam providing a braking stroke and, in the retracted position, the hydraulic actuating element may be decoupled from the brake cam providing a cylinder cutout.

A valve drive for an internal combustion engine may include a cam shaft, at least one cam follower, and at least one adjusting device. The at least one adjusting device may include a first adjustable engagement element and a second adjustable engagement element. The first engagement element may not contact a first guide in an initial position, and may cooperate with the first guide in a switching position. The second engagement element may not contact a second guide of a slide guide in an initial position, and may cooperate with the second guide in a switching position. The at least one adjusting device may further include a switching arrangement that may include a first control element mounted to the first engagement element and a second control element mounted to the second engagement element. The first control element and the second control element may be controllable via the switching arrangement.