A castellation assembly (600) can comprise a first toothed body (601) comprising a first toothed end (611) and a biased end (610) comprising a projecting lever (615). The projecting lever can be configured to extend out from the biased end and contact an actuation lever throughout a travel of the first toothed body. The second toothed body can comprise a base (620) and a second toothed end (621) configured to mesh between or stack against the first toothed end. A castellation spring (630) can be configured to push the first and second toothed body apart. An actuator assembly (40) can actuate the castellation assembly and comprise an actuating lever assembly (50) configured to reciprocate between a contacting position against the projecting lever and a clearance position spaced from the projecting lever. A rocker arm (100) in a valvetrain can be controlled for variable valve actuation thereby.

Systems for valve actuation in internal combustion engines provide rocker control components in the form of biasing mechanisms for biasing the valve side of a lost motion rocker toward the engine valves. This may prevent gaps in the valvetrain, particularly when used with cams having sub-base circle auxiliary motion event profiles. Valvetrain components, such as an e-foot engaging a valve bridge, may be provided with a biasing mechanism and stroke limiting and retaining components to maintain engagement between the e-foot and valve bridge, to control stability of the valve bridge, and to make assembly/disassembly easier.

A valve actuation system comprises a valve actuation motion source configured to provide a main valve actuation motion and an auxiliary valve actuation motion for actuating at least one engine valve via a valve actuation load path. A lost motion subtracting mechanism is arranged in a pre-rocker arm valve train component and configured, in a first default operating state, to convey at least the main valve actuation motion and configured, in a first activated state, to lose the main valve actuation motion and the auxiliary valve actuation motion. Additionally, a lost motion adding mechanism is arranged in a valve bridge and configured, in a second default operating state, to lose the auxiliary valve actuation motion and configured, in a second activated state, to convey the auxiliary valve actuation motion, wherein the lost motion adding mechanism is in series with the lost motion subtracting mechanism in the valve actuation load path.

A Type II valvetrain and engine brake arrangement includes a hydraulic brake housing mountable to a valve block of the engine. A brake piston is coupled to a brake rod and a brake cam lobe and is movable between an activated position and a non-activated position. A finger follower is disposed relative to the brake housing so that the brake rod engages the finger follower at least when the brake piston is in the activated position. When the brake piston is in a non-activated position, the finger follower is configured to pivot about a pivot as the finger follower follows a valve cam lobe to effect lifting and seating of a cylinder valve of an engine cylinder. When the brake piston is in the activated position, the finger follower, at least in part, pivots from about the pivot and the brake rod engages an end of the finger follower to lift the cylinder valve and release compression from the engine cylinder.

A method for operating a reciprocating internal combustion engine in an engine braking mode includes, in a working cycle of the engine braking mode, a first outlet valve of a first cylinder is closed for a first time, then opened for a first time, and subsequently closed for a second time, and then opened for a second time, in order to thereby discharge gas that has been compressed in the first cylinder from the first cylinder by a cylinder piston. The outlet valve is held open after the first opening and prior to the second closing long enough for the cylinder to be filled with gas that flows out of a second cylinder via at least one outlet channel, where when the engine braking mode is activated, at least one camshaft for activating at least one gas exchange valve of the reciprocating internal combustion engine is adjusted.

A compression-release engine brake system for effectuating a compression-release engine braking operation of an internal combustion engine. The compression-release system includes a lost motion exhaust rocker assembly including an exhaust rocker arm, an actuation device including an actuation piston and an actuation cavity, and a reset device including a reset check valve and a slider-piston. Hydraulic fluid in the exhaust rocker arm is locked in the actuation cavity when the reset check valve is in the closed position, and flows through the reset check valve when the reset check valve is in the open position. The slider-piston is associated with the reset check valve so that in an extended position of the slider-piston the reset check valve is free to move toward the closed position, and in a retracted position of the slider-piston the reset check valve is moved to the open position thereof by the slider-piston.

A valve train assembly includes at least a number of exhaust valves; at least one camshaft with at least a pair of a primary lift cam and an engine brake lift cam. A number of rocker arms each include a cam follower for following one of the primary lift cam and the engine brake lift cam. One rocker arm includes a cam follower following an engine brake lift cam. The rocker arm is provided with an engine brake capsule. Various biasing assemblies are disclosed that cooperate with one of the rocker arms of which the cam follower follows an engine brake lift cam to accommodate mechanical lash.

The present invention relates to a coupling device for a valve-actuating device for actuating at least one valve of a reciprocating machine having variable valve lift, in particular for a valve-actuating device of a reciprocating internal combustion engine, to a valve-actuating device and to a reciprocating machine, the coupling device comprising a first coupling element, a second coupling element and a blocking means. The first coupling element and the second coupling element can be displaced relative to one another at least within defined boundaries along a first axis, it being possible for the blocking means to block the relative displacement of the two coupling elements with respect to one another along the first axis at least in a first direction. The blocking means comprises a blocking element, which can be rotated about the first axis in the circumferential direction at least in a defined region, the relative displacement of the two coupling elements along the first axis being blocked at least in the first direction if the blocking element is in a blocking position.

A hydraulic capsule can comprise a hollow capsule body for setting the location of a plunger, a latch set alignable with a latch groove, and a latch-setting insert. The plunger can be configured to push the latch set towards the latch-setting insert. A lost motion spring can be incorporated into the hydraulic capsule, or the lost motion spring can be installed in capsule bore where the hydraulic capsule is mounted. Either a hydraulic capsule or an electromagnetic capsule or a drop in assembly can be installed in a capsule mount in a rocker arm to form a type III cam-actuated rocker arm. The rocker arm can comprise a cam side arm and a valve side arm. The rocker arm can be configured to balance a moment of inertia of the deactivation components. Twisting forces on the cam can be counteracted.

A system includes an engine with a plurality of pistons housed in respective ones of a plurality of cylinders, an air intake system provides 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 one of a plurality of exhaust valves, and a controller coupled to a sensor to control a switching tappet for compression release braking. Alternatively to a tappet, the system includes a roller finger follower controlling an opening and closing timing of exhaust valves, the roller finger follower has an inner roller follower arm adjacent an outer sliding follower, and a controller that in response to an engine braking request locks the inner roller follower arm with the outer sliding follower to contact a second cam lobe and open the exhaust valve during a compression stroke of the cylinder.