Abstract: An engine assembly may include an engine structure defining a first intake port in communication with a combustion chamber, an intake manifold, a vacuum actuated mechanism, a first intake valve, and a valve actuation assembly. The vacuum actuated mechanism may include a vacuum chamber in communication with the intake manifold. The first intake valve may open and close the first intake port. The valve actuation assembly may be engaged with the first intake valve and may be operated in first and second modes. The first mode may provide a first opening duration of the first intake valve during one of an intake stroke and a compression stroke of a piston located in the combustion chamber. The second mode may provide a second opening duration of the first intake valve that is different than the first opening duration, providing reduced intake manifold pressure.

Abstract: In a two-stroke opposed-piston engine, a ported cylinder with a pair of opposed pistons is equipped with an engine brake including an engine braking valve that can be opened to release air from the cylinder as the pistons cycle between BDC and TDC positions.

Abstract: An internal combustion engine includes an exhaust valve for removing exhaust gas from a combustion chamber and an engine braking device with a hydraulic valve control unit by which the exhaust valve is held in an intermediate open position when the engine braking device is actuated. The internal combustion engine includes a hydraulic valve lash compensation mechanism for the exhaust valve and a control channel formed between the hydraulic valve control unit and an oil feed channel for feeding oil to the hydraulic valve control unit which can be closed by a closure element to compensate for valve lash of the exhaust valve. A counter-holder is constructed as a piston-cylinder unit that forms a variable stop for a valve bridge cooperating with the valve lash compensation mechanism.

Abstract: An engine brake may include a rocker shaft, a rocker arm pivoting around the rocker shaft, an actuator piston disposed to the rocker arm and selectively protruded there from, a stopper disposed to a corresponding position of the actuator piston for the rocker arm to open a valve when the actuator piston is protruded and a hydraulic pressure supply portion selectively supplying hydraulic pressure to the actuator piston.

Abstract: In a valve drive train actuating device, particularly for an internal combustion engine, having at least one firing camshaft, which can be phase shifted relative to a crankshaft by a firing camshaft adjusting device and a decompression brake device comprising at least one brake cam and at least one decompression valve, the valve drive train actuating device comprises an adjusting device for adjusting a decompression valve drive actuating point in time depending on the speed of the crankshaft of the engine such that, with decreasing speed of the crankshaft, the brake cam actuating point is moved toward the upper dead center position of the crankshaft.

Abstract: An internal combustion engine including at least one exhaust valve for withdrawal of exhaust gas from at least one combustion chamber, and an engine brake device having a hydraulic valve auxiliary control unit by means of which the exhaust valve can be held in a temporarily open position when the engine brake device is actuated. The engine also includes a hydraulic valve play compensation mechanism for the exhaust valve, and an oil channel that for supplying oil to the valve auxiliary control unit is formed between the latter and the valve play compensation mechanism. For compensation of valve play of the exhaust valve, the oil channel can be closed off via a closure unit.

Abstract: In an in-cylinder injection type spark ignition internal combustion engine in which the intake air amount is controlled by use of an intake valve or an exhaust valve, which is provided with mainly a variable valve mechanism, instable combustion during a low-load operation is avoided without an increase in pumping loss (without a decrease in the thermal efficiency). In the in-cylinder injection type spark ignition internal combustion engine, during low-load operation, on the basis of the cooling water temperature of the engine the opening and closing timing of the intake valve is controlled in a retard angle manner and the opening and closing timing of the exhaust valve is controlled in an advance angle manner. Furthermore, the fuel injection timing is controlled in a retard angle manner on the basis of the retard angle amount of the intake valve opening and closing timing.

Abstract: A valve bridge configured to engage an engine valve is disclosed. The valve bridge includes a bridge cavity formed within a center portion of the valve bridge and including a bottom surface. A hydraulic lash adjuster is slidably disposed within the bridge cavity.

Abstract: An engine starting control apparatus is basically provided with a motor control section, a valve timing control section and a start control section. The motor control section is configured to operate an electric motor to crank an engine with an output of the electric motor being adjustable. The valve timing control section is configured to operate a variable valve operating mechanism when the engine is started to change at least a close timing of an intake valve of the engine from an initial timing corresponding to a state in which the engine is stopped to a start timing for starting the engine. The start control section is configured to adjust the output of the electric motor as the close timing of the intake valve changes from the initial timing to the start timing.

Abstract: A power system for use with an engine having at least one cylinder, and a piston, a fuel injector, and an exhaust valve associated with the at least one cylinder, is disclosed. The power system may have an exhaust passage, an aftertreatment component disposed within the exhaust passage, and a valve actuator configured to selectively move the exhaust valve. The power system may also have a controller in communication with the fuel injector and the valve actuator. The controller may be configured to make a determination to heat the aftertreatment component, to activate the valve actuator to hold open the exhaust valve as the piston moves through a top-dead-center position to disable the at least one cylinder based on the determination, and to activate the fuel injector to inject fuel into the at least one cylinder while the at least one cylinder is disabled.

Abstract: An internal combustion engine includes an exhaust valve for removing exhaust gas from a combustion chamber and an engine braking device with a hydraulic valve control unit by which the exhaust valve can be held in an intermediate open position when the engine braking device is actuated. A hydraulic valve lash compensation mechanism for the exhaust valve and a control channel formed between the hydraulic valve control unit and the valve lash compensation mechanism for feeding oil to the hydraulic valve control unit that can be closed by a closure element to compensate for the valve lash of the exhaust valve. A counter-holder is constructed as a piston-cylinder unit. The counter-holder forms a variable stop for a valve bridge cooperating with the valve lash compensation mechanism.

Abstract: A valve opening arrangement includes a first contact surface on a first member, and a second contact surface on a second member discrete from the first member. A first and a second opening are provided, and a first and a second valve movable to open and close the first and second opening, respectively, are provided. A yoke is arranged to move the first valve and not the second valve when contacted by the first contact surface and is arranged to move the first valve and the second valve when contacted by the second contact surface.

Abstract: A lost motion valve actuation system includes an engine brake housing and one or more hydraulic fluid supply passages extending through the housing. Master and slave pistons are slidably disposed corresponding bores in the housing. The master and slave pistons are used to provide selective actuation to one or more engine valves. An engine brake rocker arm disposed adjacent to the housing includes a master piston contact surface and a bias mechanism contact surface. A bias mechanism is disposed in the housing and includes a bias piston which extends from the housing. The bias piston biases the rocker arm out of contact with an engine cam during select engine operation modes, such as during a positive power mode of operation. The bias piston may be mechanically or hydraulically repositioned to permit the rocker arm to contact the engine cam during a second mode of engine operation, such as an engine braking mode.

Abstract: A compression release engine brake unit includes an oil outlet passage formed in a socket brake, which stores engine brake oil, and a reset member opening or closing the outlet passage. The reset member discharges the engine brake oil by opening the oil outlet passage in response to the rotation of a rocker arm during engine braking and, thereby, the engine brake restores the initial state. Since the compression release engine brake can restore the initial state, the return valve lift is the same as when the compression release engine brake is not actuated. Accordingly, the valve does not butt against an engine piston.

Abstract: A system for actuating an engine valve is disclosed. The system may include a rocker arm shaft (110) having a control fluid supply passage (112) and an exhaust rocker arm (500) pivotally mounted on the rocker arm shaft (110). A cam (210) for imparting main exhaust valve actuation to the exhaust rocker arm (500) may contact a cam roller associated with the exhaust rocker arm. A valve bridge (300) may be disposed between the exhaust rocker arm (500) and first and second engine valves (400, 450). A sliding pin (310) may be provided in the valve bridge (300), said sliding pin contacting the first engine valve (400). An engine braking rocker arm (100) may be pivotally mounted on the rocker arm shaft (110) adjacent to the exhaust rocker arm (500). The engine braking rocker arm may have a central opening, a hydraulic passage (102) connecting the central opening with a control valve (130), and a fluid passage (105) connecting the control valve with an actuator piston assembly (140).

Abstract: A system for actuating one or more engine valves for positive power operation and engine braking operation is disclosed. In a preferred embodiment, an exhaust valve bridge and intake valve bridge each receive valve actuations from two sets of rocker arms. Each valve bridge includes a sliding pin for actuating a single engine valve and an outer plunger disposed in the center of the valve bridge to actuate two engine valves through the bridge. The outer plunger of each valve bridge may be selectively locked to its valve bridge to provide positive power valve actuation. During engine braking, application of hydraulic pressure to the outer plungers may cause the respective valve bridges and outer plungers to unlock so that all engine braking valve actuations are provided from a rocker arm acting on one engine valve through the sliding pin.

Abstract: A supercharged diesel engine is equipped with an electronically controlled hydraulic system for variable actuation of the intake valves of the engine. The cam that controls each intake valve has an additional lobe for causing an additional opening of the intake valve, during the exhaust stroke, so as to provide an exhaust-gas recirculation directly inside the engine. Said additional lobe is shaped in such a way as to give rise to a profile of the additional lift of the valve as the crank angle varies with a boot conformation, including an initial stretch with a gentler slope extending from a point of zero lift corresponding to the expansion stroke in the engine cylinder. The engine is moreover equipped with a duct for exhaust-gas recirculation of the long-route type, which picks up the gases from a point of the exhaust duct set downstream of the catalytic converter and of the particulate trap.

Abstract: A system includes a control module, a valve control module, and a diagnostic module. The control module controls a valve of a variable intake manifold when the system operates in a first mode. The control module commands the valve to a first position when a desired airflow through the variable intake manifold is greater than a threshold and commands the valve to a second position when the desired airflow is less than the threshold. The valve control module controls the valve when the system operates in a second mode. The valve control module commands the valve to move from the second position to the first position when the desired airflow is less than the threshold. The diagnostic module determines an operating state of the valve based on whether the valve is detected at the first position a predetermined period after the valve control module commands the valve.

Abstract: A universal energy-saving system for multiple working conditions includes an electronic control unit and an actuator. The electronic control unit is adapted to sample, process running information of a vehicle and an instruction of a driver, control on and off of a fuel injector, and adapted to drive the actuator to lock or release an exhaust valve after opening the exhaust valve, so as to realize working under multiple working conditions. The features include: fuel of the engine is cut off when gliding, the exhaust valve is constantly half open, the engine races with reduced pressure; the inlet valve opens and closes normally, an inlet manifold is vacuum, direction and braking are not affected. When needing to do work or brake, the engine switches to the normal working condition automatically. Even if a fuel saving system fails, only the fuel saving function is lost, whereas other functions are normal.

Abstract: A prime mover is provided for a vehicle having a plurality of cylinder chambers, a manifold, and engine brake valves by which the cylinder chambers can be connected to the manifold. A valve or nozzle is disposed on the manifold, by which the manifold can be connected to a feed line of a compressed air treatment system.

Abstract: A power system comprising an engine that produces exhaust and includes an exhaust gas recirculation (EGR) system. The EGR system includes an EGR conduit routing an exhaust flow back to the engine, a restriction valve disposed in the EGR conduit, and a control valve disposed in the EGR conduit in series with the restriction valve.

Abstract: Apparatus and method are disclosed for converting an internal combustion engine from a normal engine operation (20) to an engine braking operation (10). The engine includes exhaust valve train components comprising at least one exhaust valve (300) and at least one cam (230) for cyclically opening and closing the at least one exhaust valve (300). The apparatus comprises actuation means (100) having at least one component integrated into at least one of the exhaust valve train components, such as a rocker arm (210) or a valve bridge (400). The actuation means (100) has an inoperative position and an operative position. In the inoperative position, the actuation means (100) is retracted and the small braking cam lobes (232 & 233) are skipped to generate a main valve lift profile (220m) for the normal engine operation (20).

Abstract: A method is disclosed for controlling compression-braking performance of an engine having a piston in a combustion cylinder. The method may include providing a valve in fluid communication with the combustion cylinder and at least one valve actuator operable to control the valve to perform compression-braking by opening the valve, which may include opening the valve to a first peak-valve-opening during a compression stroke of the piston and opening the valve to a second peak-valve-opening before a second half of an expansion stroke of the piston. The method may also include determining a target value for a stress in the at least one valve actuator. Additionally, the method may include designing the magnitude and timing of the first peak-valve-opening as a function of the target for the stress in the at least one valve actuator.

Abstract: In a gas exchange valve actuating device for transmitting a drive movement to at least one gas exchange valve of an internal combustion engine which includes a braking unit having at least one actuator, the gas exchange valve actuating device is provided with a locking unit for locking the actuator counter to an opposing force when the actuator has reached a specific position.

Abstract: A control device for a variable valve timing apparatus that changes valve timing of at least one of an intake valve and an exhaust valve of an internal combustion engine includes an actual valve timing computing unit and a valve timing controlling unit. The actual valve timing computing unit computes actual valve timing. The valve timing controlling unit controls the variable valve timing apparatus to maintain present valve timing during starting of the internal combustion engine before the actual valve timing computing unit becomes capable of computing the actual valve timing. The valve timing controlling unit controls the variable valve timing apparatus such that the actual valve timing becomes target valve timing during the starting of the internal combustion engine after the actual valve timing computing unit becomes capable of computing the actual valve timing.

Abstract: A method of camshaft scheduling is disclosed which includes measuring a driver input; calculating a driver requested torque based on a measured driver input; and scheduling the camshaft based upon the driver requested torque. In one example, the driver input is an accelerator pedal position, which is related to a percentage of driver torque requested. The cam position is selected based on the driver requested torque and the cam position is adjusted to provide one of a best fuel economy cam position and a best torque output cam position based upon the percentage of driver torque requested.

Abstract: A valve drive with a decompression brake for an internal combustion engine, which has a camshaft with a cam, a rocker arm for transmitting the cam stroke to a gas exchange valve, a pivot bearing supporting the rocker arm, and a hydraulic valve play compensating element arranged in force flow between the cam and gas exchange valve. The valve play compensating element is fixed in the engine and valve drive also has a secondary lever with a first and second lever section. The secondary lever is angularly connected, between the lever sections, to a lever support formed on the rocker arm, is supported with the first lever section on the valve play compensating element and actuates the gas exchange valve by the second lever section. The effective lever arm of the first lever section is considerably greater than the effective lever arm of the second lever section.

Abstract: A compression brake system of an internal combustion engine includes a mechanical system for coupling a camshaft to a brake actuator assembly. The mechanical system includes a stationary housing defining an aperture and a lifter is slidably disposed in the aperture. A resilient element is disposed between the housing and the shoulder and configured to bias the lifter toward the camshaft. The mechanical system is dedicated to compression braking, and therefore the camshaft may have a lobe optimized for braking.

Abstract: An internal combustion piston engine based on a four-stroke process, including a crankcase in which at least one cylinder/piston assembly is arranged, the piston being guided by a connecting rod connected to a crankshaft. At least one cylinder head closes the cylinder, each of whose intake and exhaust channels are controlled by at least one intake valve and one exhaust valve (13, 13a). The intake and exhaust valves (13, 13a) are actuable by a rocker arm (5) or a finger lever driven by a camshaft (1) through intake and exhaust cams (2). The rocker arms or finger levers are guided on at least one axle (6). A brake control device is provided which includes, in the region of the base circle of the exhaust cam (2), at least one additional cam (1) for an additional opening of at least one of the exhaust valves (13, 13a).

Abstract: A decompression braking device in an endothermic engine (1) is provided of the type comprising a lever axle (2) on which a plurality of eccentric bushings (31) of a corresponding plurality of levers (3) provided with tappets (4) are rotationally and eccentrically mounted for actuating a plurality of exhaust valves (5), and a camshaft (30) for actuating the plurality of levers (3), the device is characterized in that it comprises an actuating member (6, 61) mounted externally to the lever axle (2) and connected to the latter by linkages (8, 9, 10), such that a respective rotation of the bushings (31) by a predetermined angular value (?), with consequent displacement of the hinging axis of the levers (3), corresponds to each excursion of the actuating member (6, 61).

Abstract: The invention relates to an engine braking device (1) for an internal combustion engine comprising at least one outlet poppet valve (2) per cylinder, said valve actuatable through an outlet camshaft, wherein the engine braking device (1) acts on the outlet poppet valve (2) through a braking cam (4) of a braking camshaft (3) and through a valve lever (8) that is preferably designed as a rocker. In order to provide a low-friction engine braking device (1) in as simple a manner as possible, a piston (7) is disposed between the braking cam (4) and the valve lever (8), said piston being guided in a guide cylinder (6).

Abstract: Apparatus and method are disclosed for converting an internal combustion engine from a normal engine operation (20) to an engine braking (or retarding) operation (10). The apparatus has an actuation means (100) containing two braking pistons (160) slidably disposed in the valve bridge (400) between an inoperative position (0) and an operative position (1). The apparatus also has a flow control valve (50) for supplying control fluid to the actuation means (100) with two levels of pressure. At the first level or lower pressure, the braking pistons (160) will stay in the inoperative position (0), and a gap (234) is formed between the valve bridge (400) and the exhaust valves (300) to skip the motion from the lower portion of the cam (230) for the normal engine operation (20).

Abstract: An internal combustion engine includes a controllable throttle and controllable engine valves and is selectively operative in one of a plurality of combustion modes. An engine control method includes monitoring engine operation, determining a desired air flow, estimating a cylinder air charge, and estimating an intake air partial pressure. The throttle control device and engine valves are controlled based upon the intake air partial pressure and the cylinder air charge to achieve the desired air flow.

Abstract: A lost motion valve actuation system includes an engine brake housing and one or more hydraulic fluid supply passages extending through the housing. Master and slave pistons are slidably disposed corresponding bores in the housing. The master and slave pistons are used to provide selective actuation to one or more engine valves. An engine brake rocker arm disposed adjacent to the housing includes a master piston contact surface and a bias mechanism contact surface. A bias mechanism is disposed in the housing and includes a bias piston which extends from the housing. The bias piston biases the rocker arm out of contact with an engine cam during select engine operation modes, such as during a positive power mode of operation. The bias piston may be mechanically or hydraulically repositioned to permit the rocker arm to contact the engine cam during a second mode of engine operation, such as an engine braking mode.

Abstract: A gaseous fuel management system for an automotive vehicle includes at least one gas sensor for detecting the presence of gaseous fuel outside of the confines of the vehicle's fuel storage tank, fuel lines, and prime mover. In the event that fugitive gas is detected and the concentration exceeds a predetermined threshold, the fuel supply to the vehicle's prime mover will be shut off and, if so equipped, the vehicle may then be operated in a battery power mode for the convenience of the driver.

Abstract: Compression ignition engines and methods of the type wherein the engines operate with one cylinder used as a compression cylinder and a second cylinder used as a combustion cylinder. The engines have all cylinders configured so as to be able to operate as a compression cylinder or a combustion cylinder. In the method of operation, a cylinder may switch its operation between being a compression cylinder and then operate a combustion cylinder. Switching the operation between compression and combustion operation results in an even temperature distribution within the engine, and eliminates the need for special cooling requirements, facilitating retrofit of existing engines. Also use of an air storage tank allows all cylinders to operate as combustion cylinders for short bursts of power. Various other features are disclosed.

Abstract: An apparatus and method for varying a counter force to valve spring preload of a brake exhaust valve to undertake engine braking, includes a solenoid controlled hydraulic actuator. A control cylinder is arranged to move with a rocker arm and a control piston is arranged to slide within the control cylinder. During engine braking the control piston slides to press the valve stem to open the brake exhaust valve. An oil chamber is arranged above the control piston and is open into the control cylinder. A source of pressurized oil is selectably introduced into the oil chamber by the solenoid controlled hydraulic actuator to slide the control piston within the control cylinder to open and hold open the brake exhaust valve.

Abstract: A method for increasing an engine brake power of an internal combustion engine, particularly of a diesel engine, having at least one cylinder with a reciprocating piston, at least one inlet valve and one outlet valve, and a turbocharger, in which air is compressed by an air compressor and stored in the at least one storage device, and air is injected in a clocked manner into the at least one cylinder in order to increase the compression work performed by the piston and thereby enhance the engine brake power during an engine braking process.

Abstract: An engine brake may include a rocker shaft, a rocker arm pivoting around the rocker shaft, an actuator piston disposed to the rocker arm and selectively protruded there from, a stopper disposed to a corresponding position of the actuator piston for the rocker arm to open a valve when the actuator piston is protruded and a hydraulic pressure supply portion selectively supplying hydraulic pressure to the actuator piston.

Abstract: A method of operating an engine for a vehicle having at least a first cylinder, the method comprising of operating the first cylinder to provide at least one of compression braking and expansion braking by holding one of an intake valve and an exhaust valve of the first cylinder closed while opening, closing, and opening the other of the intake valve and the exhaust valve during a cycle of the first cylinder and during a first vacuum level of an intake manifold upstream of the first cylinder; and operating the first cylinder to provide at least one of compression braking and expansion braking by operating both the intake valve and the exhaust valve of the first cylinder during a cycle of the first cylinder to allow at least some air to flow through the first cylinder during a second vacuum level of the intake manifold.

Abstract: A system includes a fuel cutoff module and a cylinder deactivation module. The fuel cutoff module generates a fuel cutoff signal when a deceleration fuel cutoff condition occurs, wherein fueling to M cylinders of an engine is disabled based on the fuel cutoff signal, and wherein M is an integer greater than or equal to one. The cylinder deactivation module deactivates the M cylinders in response to the fuel cutoff signal.

Abstract: An internal combustion engine includes an exhaust valve for removing exhaust gas from a combustion chamber and an engine braking device with a hydraulic valve control unit by which the exhaust valve can be held in an intermediate open position when the engine braking device is actuated. A hydraulic valve lash compensation mechanism for the exhaust valve and a control channel formed between the hydraulic valve control unit and the valve lash compensation mechanism for feeding oil to the hydraulic valve control unit that can be closed by a closure element to compensate for the valve lash of the exhaust valve. A counter-holder is constructed as a piston-cylinder unit. The counter-holder forms a variable stop for a valve bridge cooperating with the valve lash compensation mechanism.

Abstract: An internal combustion engine includes an exhaust valve for removing exhaust gas from a combustion chamber and an engine braking device with a hydraulic valve control unit by which the exhaust valve is held in an intermediate open position when the engine braking device is actuated. The internal combustion engine includes a hydraulic valve lash compensation mechanism for the exhaust valve and a control channel formed between the hydraulic valve control unit and an oil feed channel for feeding oil to the hydraulic valve control unit which can be closed by a closure element to compensate for valve lash of the exhaust valve. A counter-holder is constructed as a piston-cylinder unit that forms a variable stop for a valve bridge cooperating with the valve lash compensation mechanism.

Abstract: An engine brake unit, may include a rocker shaft having an oil passage to open or close an exhaust valve when an engine braking is in operation, an exhaust rocker arm rotatable about the rocker shaft inserted into the exhaust rocker arm, wherein the exhaust rocker arm includes a supply oil passage communicating with the oil passage and the outside, and a recess connected to the supply oil passage and having an open lower portion, an actuator disposed in the recess of the exhaust rocker arm, wherein the actuator includes a piston that selectively moves downwards through the open lower portion of the recess by oil supplied from the supply oil passage to press the exhaust rocker arm while oil pressure in the oil passage has a predetermined pressure or more, and an oil control valve connected to the oil passage of the rocker shaft and controlling the oil pressure.

Abstract: An engine braking system for vehicles may include a rocker shaft having a lubricating oil passage and a braking oil passage, a valve unit selectively supplying part of the oil supplied to the lubricating oil passage, into the braking oil passage, and at least one exhaust rocker arm, into which the rocker shaft is inserted and pivotal about the rocker shaft, wherein the at least one exhaust rocker arm has, therein, a first connection passage communicating with the braking oil passage and a first recess, a stopper fixed above the first recess, and an actuator housed in the first recess and including a pressing piston, wherein the pressing piston moves to contact the stopper by hydraulic pressure of the oil supplied from the braking oil passage into the first recess and thus presses the at least one exhaust rocker arm in a downward direction.

Abstract: A valve timing control apparatus for an internal combustion engine includes a variable valve timing mechanism. The valve timing control apparatus sets target valve timing based on an operational state of the engine. The valve timing control apparatus detects actual valve timing. The valve timing control apparatus computes a control amount based on a deviation between the target valve timing and the actual valve timing, and based on a hold control amount. The valve timing control apparatus determines whether a learning execution condition for executing a learning operation of the hold control amount is satisfied based on a change direction of the detected actual valve timing. The valve timing control apparatus executes the learning operation when the learning execution condition is satisfied.

Abstract: Apparatus and method are disclosed for converting an internal combustion engine from a normal engine operation (20) to an engine braking (or retarding) operation (10). The engine has an exhaust valve train containing two exhaust valves (300), a valve bridge (400) and an exhaust valve lifter (200). The apparatus has an actuation means (100) including a hydraulic system integrated into the exhaust valve train. The hydraulic system contains a braking piston (160) slidably disposed in the valve bridge between an inoperative position (0) and an operative position (1). In the inoperative position, the braking piston is retracted and the actuation means disengaged from the normal engine operation. In the operative position, the hydraulic piston is extended and the actuation means opens one of the two exhaust valves (300a) for the engine braking operation.

Abstract: Apparatus for modifying engine valve lift to produce an engine valve event in an internal combustion engine, the engine including at least one exhaust valve and an exhaust valve lifter for cyclically opening and closing the at least one exhaust valve, includes (a) an actuator for operating the at least one exhaust valve to produce said modified engine valve lift, said actuator having an inoperative position and an operative position; in said inoperative position said actuator being disengaged from the operation of the at least one exhaust valve, and in said operative position said actuator opening the at least one exhaust valve for said engine valve event; and (b) a controller for moving said actuator between said inoperative position and said operative position.

Abstract: An internal combustion engine has intake (20) and exhaust (22) poppet valves, a first and a second set of cam lobes (64) for operating the intake and exhaust poppet valves (20,22) respectively, and a third set of cam lobes (68) for producing an additional selectable valve event in order to allow the engine to operate as a compression brake. The third set of cam lobes (68) and at least one of the first and second set of cam lobes (64) are rotatable relative to one another and form part of an assembled camshaft (60) so as to be rotatable about a common axis. A phasing system (50) acts on the assembled camshaft (60) to allow the phase of the third set of cam lobes (68) to be changed relative to the engine crankshaft.

Abstract: An engine provided with a variable timing mechanism (B) able to control a closing timing of an intake valve (7) and a variable compression ratio mechanism (A) able to change a mechanical compression ratio and controlling the closing timing of the intake valve (7) to control the amount of intake air fed into a combustion chamber (5). To obtain an output torque in accordance with the required torque even when the atmospheric pressure changes, when the atmospheric pressure falls, the closing timing of the intake valve (7) is made to approach intake bottom dead center and the mechanical compression ratio is reduced.