A switchable valve train assembly including a carrier housing defining a hydraulic circuit, a supply assembly, a plurality of rocker shafts, a plurality of separators, and a plurality of rocker arm assemblies is provided. Each one of the plurality of separators divides the rocker shafts into (1) a first chamber extending between a first chamber axial end and the separator, and (2) a second chamber extending between a second chamber axial end and the separator. The plurality of separators each include an orifice defined between the first chamber and the second chamber that provides fluid connection between the first chamber and the second chamber. Locking assemblies of the rocker arm assemblies are selectively actuated based on the supply assembly. The separators ensure that hydraulic fluid within the hydraulic fluid is de-aerated and that the second chambers remain primed with hydraulic fluid for faster actuation of the locking assemblies.

A rocker arm assembly for an engine is configured to fit about a pivot shaft that extends along a central axis. The assembly includes an intermediate shaft configured to be rotatably disposed about the pivot shaft. A cam-side arm is pivotable about the central axis and is configured to be driven by a cam. A valve-side arm is pivotable about the central axis and relative to the cam-side arm, and is configured to convert rotation of the rocker arm assembly about the central axis into operation of an engine valve. An annular compressible fluid chamber is disposed between the intermediate shaft and the valve-side arm. When the cam-side arm and the intermediate shaft are engaged, pivoting of the cam-side arm compresses fluid within the chamber, causing corresponding pivoting of the valve-side arm and operation of the valve. The fluid provides hydraulic lash adjustment.

A valve train for an internal combustion engine may include a camshaft and a cam follower. The valve train may also include two first cams arranged on the camshaft in a torque-proof manner and at an axial distance from one another. Each of the two first cams may include an identical first cam contour. The valve train may also include two second cams arranged on the camshaft in a torque-proof manner and at an axial distance from one another. Each of the two second cams may also include an identical second cam contour. The two first cams and the two second cams may alternate in an axial direction on the camshaft. The cam follower may be axially adjustable between a first and second position, and may be drivingly connected to the two first cams in the first position and drivingly connected to the two second cams in the second position.

The control apparatus operates an engine water temperature adjustment apparatus so that the temperature of cooling water that passes through an engine head enters a first temperature region in a lean mode, and operates the engine water temperature adjustment apparatus so that the temperature of the cooling water enters a second temperature region that is lower than the first temperature region in a stoichiometric mode. When knocking is detected after switching is started from the stoichiometric mode to the lean mode, the control apparatus performs any one of a first operation to operate a variable valve apparatus so as to retard the closing timing of an intake valve, a second operation to operate an oil jet apparatus so as to increase an oil jet amount, and a third operation to operate an EGR apparatus so as to increase an EGR amount.

A compression-release brake system is provided that includes a lost motion exhaust rocker assembly, an actuation piston, and a reset device. The actuation piston includes an actuation piston body that is slidably received by the rocker arm to define a piston cavity in the rocker arm and is movable between piston retracted and extended positions. The actuation piston is configured to be operatively associated with the exhaust valve to permit unseating of the exhaust valve from the seated state. An actuation piston check valve is configured to move between closed and open positions to permit hydraulic fluid flow through an actuation piston communication port to the piston cavity. The reset device includes a reset check valve and a reset pressure control spring for applying a biasing force to the reset check valve to urge the reset check valve toward an open position.

A method is disclosed for controlling an internal combustion engine having a first adjustable camshaft for the actuating of first valve elements of the internal combustion engine. An effect of an actuation at least of a first valve element by the first camshaft on this valve element is detected. An actual position of the first camshaft and/or of a crankshaft driving the latter is detected on the basis of this detecting of the effect. An adjustment of the first camshaft is calibrated on the basis of a first deviation between this detected actual position and a predetermined required position.

A mechanical system that forms one of a cam follower or a rocker arm. The mechanical system comprises a support element including a first body portion and a second body portion, a pin extending between two opposite ends along a first axis and supported by the first body portion of the support element, and a roller mounted on pin, movable in rotation relative to the pin around the first axis and adapted to roll on a cam. The mechanical system further comprises a spacing element comprising a first body portion connected to the second body part of the support element and a second body portion adapted to be supported by a movable support.

A multiple variable valve lift apparatus includes a camshaft. At least two cam portions are disposed on an exterior circumference of the camshaft and including a high cam and a normal cam. A cylinder deactivation device is configured to perform a lever motion by one of the high cam or the normal cam and to be operated by hydraulic pressure. At least two lift operating portions are disposed on the exterior circumference of the camshaft and moving the cam portions in an axial direction of the camshaft. An operation control portion selectively moves the operating portions in the axial direction of the camshaft. A guide rail is formed in a groove of an exterior circumference of the lift operating portions into which a pin is inserted. The guide rail guides the pin according to rotation of the camshaft and the operating portions.

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.

An engine braking method includes the steps of engaging a cam roller(235) of an internal combustion engine with an engine power cam(230) for an engine power operation; disengaging the cam roller(235) from the engine power cam(230); losing a motion from the engine power cam(230) and a motion of an engine valve(301) associated with the motion from the engine power cam(230); engaging the cam roller(235) with an engine braking cam(2302) for an engine braking operation; transmitting a motion from the engine braking cam(2302) to the engine valve(301); and generating an engine valve motion for the engine braking operation. An engine braking system includes an engine power cam(230) of an internal combustion engine; an engine braking cam(2302) of the internal combustion engine; and a cam roller(235) that is designed to engage with the engine power cam(230) for an engine power operation and to engage with the engine braking cam(2302) for an engine braking operation.