A hydraulic lash adjuster for use in diesel engines including a cylinder head having a first valve, a second valve, and a valve bridge extending between and in contact with both the first valve and the second valve. Where the diesel engine includes a first rocker arm, and where at least one of the first valve and the second valve undergo an oil can valve deflection rate. The hydraulic lash is configured to selectively transmit force between the first rocker arm and the valve bridge, and where the hydraulic lash adjuster is normally in the open configuration, and where the hydraulic lash adjuster changes from the open configuration to a closed configuration at a critical velocity that is greater than the oil can valve deflection rate.

An exhaust valve opening apparatus such as for an engine compression braking system includes a rocker shaft for supplying control fluid to an controllable valve and for distributing the control fluid to a primary and second piston arrangement that selectively opens an exhaust valve in response to the control fluid being pressurized.

A modular exhaust valve rocker arm assembly system comprising first and second rocker arm assemblies configured to each selectively receive a hydraulic lash adjustment assembly or a mechanical lash adjustment assembly. A main lifter assembly operably associated with the first and second rocker arm assemblies. An added motion lifter assembly operably associated with the first rocker arm assembly and configured to selectively provide one of an early lift profile and an extended lift profile, which can comprise at least one of an engine braking feature, a late intake valve closing (LIVC) feature, and an early exhaust valve opening (EEVO) feature. The main lifter can be configured as a fixed lifter or as a deactivating lifter for cylinder deactivation (CDA) configured to selectively move to a deactivated state configured to absorb motion of a normal lift profile cam into lost motion.

Systems and methods for an engine are provided. The engine includes a straight rocker shaft passing through each of a first rocker arm and a second rocker arm, the first rocker arm being shaped differently from the second rocker arm.

A valve actuation system for actuating at least one engine valve comprises a first half-rocker arm configured to receive main valve actuation motions from a main valve actuation motion source and a second rocker arm configured to actuate the at least one engine valve. A collapsing mechanism is also provided and configured relative to the first half-rocker arm and the second rocker arm, in a first collapsing mechanism state, to convey the main valve actuation motions from the first half-rocker arm to the second rocker arm and, in a second collapsing mechanism state, to prevent conveyance of the main valve actuation motions from the first half-rocker arm to the second rocker arm. The collapsing mechanism may be disposed in the first half-rocker arm or the second rocker arm, where the rocker arm not including the collapsing mechanism is provided with a collapsing mechanism contact surface.

A novel cylinder head arrangement for an in-line four cylinder or eight cylinder engine. A modified arrangement allows additional space for installation of wider rocker arm assemblies used for variable valve lift (VVL), cylinder deactivation (CDA) and other types of variable valve actuation (VVA). In one embodiment, cam towers adjacent the end two cylinders are not used. At least one end support is used, which may be an outboard bearing on a camshaft for each end. The wider rocker assemblies may then be installed. In another embodiment, cam towers adjacent the inner two cylinders are eliminated and a single camshaft support piece with a support bearing is installed between the inner cylinders to provide support for the camshafts. The wider rocker assemblies may then be installed on at least one of the middle cylinders. A novel oil control valve operates latches in switching rocker arm assemblies.

An exhaust valve rocker arm assembly operable in a drive mode and an engine braking mode includes a rocker shaft, a rocker arm, a hydraulic lash adjuster assembly, an accumulator assembly and a locking pin. The rocker shaft has an oil gallery defined thereon. The rocker arm receives the rocker shaft and is configured to rotate around the rocker shaft. The rocker arm has an oil feed channel that is fluidly connected to the oil gallery. The rocker arm further defines an engine brake relief hold and an accumulator relief hole. The accumulator assembly is disposed in the rocker arm and is fluidly coupled to the hydraulic lash adjuster through an engine brake relief hole. The locking pin assembly is disposed in the rocker am and is selectively movable by a high pressure fluid from a closed position to an open position.

A rocker arm assembly selectively opening first and second engine valves. The assembly includes a rocker arm and a valve bridge operably associated with the rocker arm and including a main body and a lever rotatably coupled to the main body. The main body is configured to engage the first engine valve, and the lever is configured to engage the second engine valve.

A rocker arm assembly having a rocker arm including a pair of sidewalls, each sidewall defining a support aperture, a rocker arm support including a pair of opposed bearing support arms, each bearing support arm being disposed within a corresponding support aperture of the rocker arm and defining a lubrication groove extending along an outer surface thereof, and a pair of radial roller bearings, each including an inner cup, an outer cup, and a plurality of rollers disposed therebetween, wherein each radial roller bearing is disposed both on a corresponding bearing support arm and within a corresponding support aperture.

A compression release type of engine brake socket module is provided between an exhaust rocker arm rotating with respect to a rocker arm shaft and a valve bridge connecting an exhaust valve of an engine. In particular the socket module incudes: a housing which includes an inlet through which brake oil is introduced, a brake piston mounting portion, and a reset member mounting portion communicating with the brake piston mounting portion; a brake piston that is provided to be movable in the brake piston mounting portion; a stopper disposed on one side of an inner space of the housing to limit a moving position of the brake piston; and a reset member that is provided in the reset member mounting portion, and that discharges the brake oil by selectively contacting a push pin coupled to an upper portion of a cylinder head.