174 results about "Compression release" patented technology

A method and system for actuating an internal combustion engine exhaust vaive to provide compression release actuation during an engine braking mode of engine operation and early exhaust valve opening actuation during a positive power mode of engine operation is disclosed. The system may include a first cam having a compression release lobe and an early exhaust valve opening lobe connected to a hydraulic lost motion system including a first rocker arm. A hydraulically actuated piston may be selectively extended from the hydraulic lost motion system to provide the exhaust valve with compression release actuation or early exhaust valve opening actuation. The hydraulicaily actuated piston may be provided as a slave piston in a master-slave piston circuit in a fixed housing, or alternatively, as a hydraulic piston slidably disposed in a rocker arm. The method and system may further provide exhaust gas recirculation and / or brake gas recirculation in combination with compression release actuation and early exhaust valve opening actuation.

A compression-release brake system for operating an exhaust valve of an engine during an engine braking operation. The compression-release brake system comprises a self-contained compression brake control module (CBCM) operatively coupled to the exhaust valve for controlling a lift and a phase angle thereof and a source of a pressurized hydraulic fluid. The CBCM includes a casing defining piston and actuator cavities, a slave piston mounted within the piston cavity, a check valve provided between a supply conduit and a slave piston chamber and a compression brake actuator disposed in the actuator cavity. The compression brake actuator includes an actuator element and a biasing spring. The actuator element selectively engages the check valve when deactivated so as to unlock the slave piston chamber, and disengages from the check valve when activated so as to lock the slave piston chamber. The actuator element is exposed to atmospheric pressure.

The present invention discloses a method and apparatus for implementing blower type engine braking and compression-release type engine braking on an internal combustion engine. With blower-type engine braking, the exhaust valve is held at a relatively constant low lift during all or most of the engine's operating cycle. Engine braking may be combined with operation of exhaust gas recirculation, variable exhaust brake operation, and / or operation of a variable geometry turbocharger.

A tool for the removal and replacement of valve springs on the cylinder head of an internal combustion engine while the cylinder head is either mounted to the engine block within the vehicle or is positioned on a work bench apart from the engine. The tool comprises a bracket component that is mounted by a number of bolts to the cylinder head to be worked on. The bracket includes a number of upright threaded bolts each associated with an adjacent upright guide. A pressure plate is progressively positioned on each set of the upright bolts and upright guides. Beneath the pressure plate are positioned two (or more) valve guides that engage the outer upper perimeter of two or more valve springs. A nut is threaded on to the upright bolt in a manner that forces the pressure plate and the valve guides downward onto the valve springs. Compression of the springs releases the split rings or collars that hold the valve springs to the valve stems. The end of the valve stems that incorporate the split ring attachment mechanisms are allowed to move upward into the valve guides while the perimeter of the spring is compressed. In this manner the split ring can be removed and the springs released upon removal of the nut from the threaded upright bolt. The pressure plate may then be moved to the next upright bolt on the bracket to effect removal of the adjacent set of valve springs.