Abstract: An ECU 70A is associated with an engine 1 provided with a VVT 30 capable of independently setting a phase of an intake valve 2A and a phase of an intake valve 2B of two intake valves 2 mounted for a combustion chamber E. The ECU 70A includes a controller control the VVT 30 based on a magnitude of engine brake required to the engine 1 to vary a phase of at least one of the intake valves 2A and 2B.

Abstract: A system for actuating an engine valve to decompress an engine cylinder for engine start up and/or engine braking is disclosed. The system may include a first member, such as an outer piston, disposed above an engine valve, which receives an inner piston extending into a bore provided in the first member. One or more springs may bias the inner piston into a predefined position in the first member. The inner piston may include a lower surface that directly, or through an intervening sliding pin, actuates an engine valve in response to the application of fluid pressure on the inner piston. The inner piston may be used to decompress an engine cylinder for engine start up and/or to provide engine braking.

Abstract: The present disclosure is directed at the control of an effective compression ratio setting in an engine which may use a variety of fuels or fuel blends. The effective compression ratio may be selected based upon information from a fuel sensor and stored information regarding the detected fuel composition. The effective compression ratio may be adjusted for a selected cylinder by intake or exhaust valve timing.

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: In controlling valve motions of an internal combustion engine, after determining that engine braking operation has been initiated, a deactivation mechanism disposed within a main valve train is activated thereby disabling conveyance of main valve events from a main valve motion source to a valve via the main valve train. Engine braking valve events are enabled for the valve, which may include two-stroke engine braking. Coupling mechanisms, including one-way coupling mechanisms, between adjacent rocker arms may be used in this manner.

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: 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 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: While an engine is miming with all engine cylinders being fueled, a historical record of engine output torque and engine speed is compiled. When the historical record discloses a change in engine operation from a relatively greater output torque and engine speed to a relatively lesser output torque and speed, fueling of at least one engine cylinder ceases while engine output torque and engine speed remain substantially unchanged at the relatively lesser output torque and speed by continuing fueling of other engine cylinders and by causing at least one mechanism to control the timing of operation of cylinder intake and exhaust valves of the at least one engine cylinder to substantially minimize pumping loss attributable to the at least one engine cylinder.

Abstract: A motor vehicle provided with an internal combustion engine having a system for variable actuation of the intake valves has a phase of activation of an operating mode with the engine off and the vehicle moving, in which the fuel supply to the engine is cut-off. After the cut-off of the fuel supply to the engine, the system for variable actuation of the intake valves is controlled to vary the opening time and/or closing time and/or the lift of the intake valves so as to control the losses due to the pumping effect which occur within the engine in cut-off condition.

Abstract: A valve actuation mechanism includes rockers moved by a camshaft, each rocker being adapted to exert a valve opening force on at least a portion of a valve opening actuator of each cylinder, via an activation piston, housed in a bore of the rocker and movable with respect to the rocker under action of a fluid pressure raise in a chamber fluidly linked to the bore, from a first position to a second position, in which a cam follower of the rocker reads at least one auxiliary cam sector of a cam of the camshaft so as to perform an engine operating function. Each rocker includes a reset valve adapted to reduce fluid pressure in the chamber. The valve actuation mechanism includes, for each rocker, a reset cam profile adapted to open the reset valve when the activation piston has to be moved from its second position to its first position, and each reset valve includes a cam follower adapted to drive the reset valve as a function of the movement of the reset profile.

Abstract: A control system and method for engine braking for a includes an engine braking control and at least one exhaust valve actuator responsive to demands from the braking control for causing the exhaust valve to open. The braking control is configured to command the exhaust valve actuator to substantially open and substantially close the exhaust valve at least twice during each engine cycle, a first event and a second event, when the pressure within the exhaust manifold is greater than the pressure in the cylinder. The braking control can also command the exhaust valve actuator to substantially open and substantially close during a third event between the first and second events.

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: A method is provided for controlling an engine via an outlet control device of an intake manifold, such as via variable valve lift operation. The engine may further include an inlet control device, such as an electronic throttle, as well as coordination between the inlet and outlet control devices for controlling airflow in the engine.

Abstract: During a caulking process, a pressure is applied to a pressure receiving shoulder portion in the same direction as a direction of a clamping force generated by a caulking portion. The clamping force for holding an outer race can thereby be increased. Also, a pressure receiving surface of the pressure receiving shoulder portion is set higher than an end face. Thus, no pressure resulting from plastic deformation in a direction perpendicular to the direction of the clamping force of the caulking portion is generated. In addition, a groove is formed between the pressure receiving shoulder portion and an end serving as the caulking portion.

Abstract: A valve control system includes an engine speed control module that determines an engine speed and a desired engine stop position. A piston position module determines a desired stopping position of a first piston based on the desired engine stop position. A valve control module receives the desired stopping position, commands a set of valves to close at the desired stopping position if the engine speed is less than a predetermined shutdown threshold, and commands the set of valves to reduce the engine speed if the engine speed is greater than the predetermined shutdown threshold.

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 engine brake unit may include a rocker arm having a first space defined in a valve-pressing portion thereof, wherein the first space communicates with a supply passage, through which engine brake oil is introduced, a stopper fixedly provided above the first space of the rocker arm in a predetermined distance, an actuator located inside the first space and having a pressure piston, wherein the pressure piston is selectively raised by hydraulic pressure of the engine brake oil to butt against the stopper, thereby pressing a portion of the rocker arm downwards.

Abstract: An engine for use in an air hybrid vehicle comprises at least one cylinder having a piston (20) defining a variable volume working chamber (10) and intake (12, 14) and exhaust (16) valves controlling the flow of air into and out of the working chamber. The cylinder is operable in any one of at least two modes, namely a first mode in which power is generated by burning fuel in the working chamber (10), and a second mode in which the cylinder acts to compress air drawn into the working chamber (10) and to store the compressed air in an air tank (36). The engine further comprises a non-return valve (32) in an intake port leading to an intake valve (12) of the cylinder so as to define an auxiliary chamber (30) in the intake port between the intake valve (12) and the non-return valve (32). A passage (24) connecting the auxiliary chamber (30) to the air tank (36) contains a valve (34) for controlling the flow of compressed air between the auxiliary chamber (30) and the air tank (36).

Abstract: A machine includes a power source, an engine retarder associated with the power source, and a traction device receiving power from the power source and configured to propel the machine. The machine also includes a brake mechanism associated with the traction device, and a controller in communication with the engine retarder and the brake mechanism. The controller is configured to activate the engine retarder, substantially simultaneously with the brake mechanism, based on a brake pressure associated with the brake mechanism.

Abstract: A method and a device for controlling the engine braking operation in internal combustion engines for motor vehicles, wherein the internal combustion engine is operated with direct injection of fuel and a controllable brake flap is provided in the exhaust gas system for retaining exhaust gases in the engine braking operation, and moreover has an exhaust gas recirculation device having an EGR valve that is arranged upstream of the brake flap and a recirculation line that connects the exhaust gas system to the intake system of the internal combustion engine and during the driving operation controls a defined quantity of recirculated exhaust gas with respect to the combustion air. To avoid critical excessive temperatures at the injection valves, in the engine braking operation (MB), the EGR valve (13) is more or less opened in dependence upon operating parameters (n, TE) of the internal combustion engine (1).

Abstract: An ECU 70A is associated with an engine 1 provided with a VVT 30 capable of independently setting a phase of an intake valve 2A and a phase of an intake valve 2B of two intake valves 2 mounted for a combustion chamber E. The ECU 70A includes a controller control the VVT 30 based on a magnitude of engine brake required to the engine 1 to vary a phase of at least one of the intake valves 2A and 2B.

Abstract: A valve control apparatus is provided for an internal combustion engine. The apparatus includes a variable phase angle mechanism configured to continuously change a valve opening phase angle of a valve, a variable valve mechanism configured to continuously change at least one of a valve opening duration and a valve lift of the valve, and a controller configured to control the variable phase angle mechanism and the variable valve mechanism. The variable phase angle mechanism is configured to set the valve opening phase angle at a retarded phase angle in a startup operation as compared with a normal phase angle in a normal operation. After an engine stop command is generated, the controller controls the variable valve mechanism such that an integrated valve opening value is increased to be larger than an idle state integrated valve opening value in an idle state.

Abstract: An idling-time target phase setting unit (130) variably sets a target phase based on a target idle speed that is set by a target idle speed setting unit. (110) Especially, when the target idle speed is lower than a predetermined rotational speed and operating noise of a variable valve timing mechanism (2000) is easily heard by, for example, a driver, the.idling-time? target phase setting unit (130) sets the target phase so that a range, in which the valve phase is allowed to change, is restricted within a phase region where a speed reduction ratio is high and the operating noise is relatively low.

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 method and control module includes a manifold absolute pressure comparison module that determines a function of the manifold absolute pressure and an average manifold absolute pressure for a plurality of cylinders and that compares the manifold absolute pressure parameter to a manifold absolute pressure threshold. The control module includes a misfire event module that compares the misfire parameter to a misfire threshold. A hardware remedy module performs a valve actuation hardware remedy in response to comparing the manifold absolute pressure and comparing the misfire parameter.

Abstract: A control method and a control system for deceleration of a vehicle including a continuous valve lift apparatus (CVVL) may include determining whether fuel cutting condition is satisfied, determining whether brake pedal input signal is detected and controlling deceleration according to brake pedal input signal by at least one of controlling throttle opening angle and controlling valve lift of the CVVL.

Abstract: A method is provided for controlling an engine via an outlet control device of an intake manifold, such as via variable valve lift operation. The engine may further include an inlet control device, such as an electronic throttle, as well as coordination between the inlet and outlet control devices for controlling airflow in the engine.

Abstract: Methods and systems are provided for addressing pre-ignition that may be induced in response to actions taken to mitigate a cylinder misfire. An amount of engine load limiting applied may be adjusted to reduce the likelihood pre-ignition while also addressing component over-temperature issues. By limiting an engine load while shutting off fuel in a misfiring cylinder, and while combusting a lean air-fuel mixture in the remaining cylinders, pre-ignition induced by the misfire-mitigating lean combustion conditions can be reduced.

Abstract: A hydraulic valve actuation assembly may include a housing, a piston, a supply control valve, a closing control valve, and an opening control valve. The housing may define a first fluid chamber, a second fluid chamber, and a third fluid chamber. The piston may be axially secured to an engine valve and located within the first, second and third fluid chambers. The supply control valve may control a hydraulic fluid supply to the piston. The closing control valve may be located between the supply control valve and the second fluid chamber and may control fluid flow from the second fluid chamber to the supply control valve. The opening control valve may be located between the supply control valve and the second fluid chamber and may control fluid flow from the supply control valve to the second fluid chamber.

Abstract: A device includes: actual-intake-pipe-pressure detection unit (11); estimated-intake-pipe-pressure detection unit (12) for calculating an estimated intake pipe pressure based on a rotation speed of the engine and an opening degree of a throttle valve; pressure difference calculation unit (13) for calculating a pressure difference between the actual and estimated intake pipe pressures; pressure difference integration unit (14) for integrating the pressure difference with respect to time; pumping brake detection unit (15) for determining that a pumping brake operation is performed when a integral value is equal to or more than a first determination value; and throttle valve control unit (16) for carrying out control for the pumping brake during the pumping brake operation based on a result of the determination by the pumping brake detection unit (15), and carrying out ordinary control otherwise.

Abstract: An engine braking system includes a turbocharger having a turbine and a compressor. An exhaust manifold includes a first pipe for channeling a first portion of the engine exhaust and a second pipe for channeling a second portion of the engine exhaust. The first and second pipes are connected to an inlet of the turbine. A cross pipe, as part of an exhaust gas recirculation (EGR) conduit, is open between the first and second pipes and at one end to the remaining portion of the EGR conduit. A valve can be arranged within the cross pipe and ca be operable in a first mode of operation to block flow between the first and second pipes and allow flow between the first pipe and the remaining portion of the EGR conduit and to allow flow between the first and second pipes and the inlet of the turbine. The valve is operable in a second mode of operation to allow flow between the first and second pipes, and to reduce or block flow between the second pipe and the turbine inlet.

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: A method for timing performance of a maintenance function, in particular the timing of regeneration of a diesel particulate filter (22) to conserve fuel as a motor vehicle (10) travels along a projected travel route. Certain road data about roads in a roadway system is processed to develop data for anticipating certain modes of vehicle operation during travel of the vehicle along the projected travel route. The data for anticipating certain modes of vehicle operation along the anticipated route of travel and data geographically tracking vehicle travel along the projected route are interactively used to control timing of performance of the maintenance function as the vehicle travels along the projected route.

Abstract: A valve control system includes an engine speed control module that determines an engine speed and a desired engine stop position. A piston position module determines a desired stopping position of a first piston based on the desired engine stop position. A valve control module receives the desired stopping position, commands a set of valves to close at the desired stopping position if the engine speed is less than a predetermined shutdown threshold, and commands the set of valves to reduce the engine speed if the engine speed is greater than the predetermined shutdown threshold.

Abstract: A system for actuating an engine valve to decompress an engine cylinder for engine start up and/or engine braking is disclosed. The system may include a first member, such as an outer piston, disposed above an engine valve, which receives an inner piston extending into a bore provided in the first member. One or more springs may bias the inner piston into a predefined position in the first member. The inner piston may include a lower surface that directly, or through an intervening sliding pin, actuates an engine valve in response to the application of fluid pressure on the inner piston. The inner piston may be used to decompress an engine cylinder for engine start up and/or to provide engine braking.

Abstract: In a control device which uses a specific physical quantity as a control variable of an internal combustion engine, and controls the internal combustion engine by manipulation of one or a plurality of actuators, switching of setting of a manipulation variable based on a required value of a physical quantity and setting of the manipulation variables by direct instruction to individual actuators is performed without generating discontinuity in a realized value of the physical quantity. When a manipulation variable instruction value directly designating a manipulation variable of an actuator is present, the manipulation variable instruction value is converted into a value of a physical quantity which is realized in the internal combustion engine by the operation quantity instruction value.

Abstract: An engine assembly may include an engine structure, a piston, a first valve and a first valve actuation assembly. The engine structure may define a combustion chamber and a first port in communication with the combustion chamber. The piston may be located within the combustion chamber and be reciprocally displaceable between a top dead center position and bottom dead center position. The first valve may selectively open and close the first port. The first valve actuation assembly may be engaged with the first valve and be operable in first and second modes. The first valve actuation assembly may be operated in the first mode when fuel is provided to the combustion chamber and operated in the second mode when fuel is cutoff from the combustion chamber. The first mode and second modes may provide different opening durations of the first valve in order to reduce vacuum in the combustion chamber.

Abstract: A four-stroke internal combustion engine, having a brake controller by which pressure is built up in the exhaust system and/or at least one exhaust valve is additionally opened is provided. A hydraulic valve clearance compensation element is incorporated in at least one transmission element between the camshaft and at least one intake and exhaust valve and has at least one piston (3), a cylinder housing part (2) that interacts with the piston (3), a return spring (16) disposed therebetween, a check valve (4), and an actuatable locking device is provided which limits the movement of the piston (3) relative to the cylinder housing part (2) and/or limits the movement of the cylinder housing part (2) relative to an exterior housing (1) connected to one of the transmission elements or relative to a transmission element at least in one direction of movement, and the piston (3) is supported on a stop element (5) connected to the exterior housing (1) or the transmission element.

Abstract: A valve mechanism for an internal combustion engine is operable to selectively open and close a gas exchange valve to accomplish an engine brake during an engine brake mode of an engine. The valve mechanism includes a cam follower in biased abutment against a gas exchange cam element for actuation of a rocker arm connected to the gas exchange valve.

Abstract: A method is provided for controlling an engine via an outlet control device of an intake manifold, such as via variable valve lift operation. The engine may further include an inlet control device, such as an electronic throttle, as well as coordination between the inlet and outlet control devices for controlling airflow in the engine.

Abstract: A method and system for operating a combustion engine brake especially for a heavy vehicle like a truck or a bus is disclosed. By detecting a brake torque value which is delivered by the combustion engine brake for braking the vehicle, and, if the amount of the difference between a demanded brake torque value and the delivered brake torque value exceeds a predetermined first limit value, by operating the combustion engine brake by means of at least one additional or alternative second operating parameter which is selected in order to create a corrected brake torque value, a considerably improved accuracy, efficiency and/or reliability of the combustion engine brake can be obtained.

Abstract: A driving control system includes a controller which is configured to, in response to a command for starting an auto-cruise mode generated by the operation of an input device, control an engine speed or a vehicle speed so that a value detected by a speed detector falls within a cruising speed range, when the value detected by the speed detector is outside the cruising speed range; and to then cause the watercraft to cruise at a constant engine speed or at a constant vehicle speed.

Abstract: There is provided, in one aspect of the present description, a method of controlling a spark ignited internal combustion engine having a fuel injector which injects fuel directly into its combustion chamber. The method comprises stopping the fuel injection if a desired torque for the engine is a predetermined torque or less and a speed of the engine is a predetermined speed or greater. The method comprises resuming the fuel injection by injecting a first amount of fuel directly into the combustion chamber during a negative pressure period and injecting a second amount of the fuel into the combustion chamber during an intake period. The method further includes resuming the fuel injection by injecting a third amount of the fuel directly into the combustion chamber during the negative pressure period and injecting a fourth amount of the fuel into the combustion chamber during the intake period.

Abstract: A control apparatus for an internal combustion engine (10) includes intake valve control means (50). The internal combustion engine (10) includes a variable intake valve operating mechanism (66) that changes a valve opening characteristic of an intake valve (64), and rich combustion is performed in the internal combustion engine (10) to control an exhaust gas purification catalyst (24) disposed in an exhaust passage (18). The intake valve control means (50) controls the valve opening characteristic of the intake valve (64) to increase a flow rate of intake air in an early stage of an intake stroke when the rich combustion is performed, as compared to when non-rich combustion is performed.

Abstract: In a method for reducing engine vibrations during engine braking with a malfunctioning engine brake, the engine brake includes an arrangement for altering a timing of at least one exhaust valve and an arrangement for varying an exhaust gas back pressure. The method includes detecting piston acceleration for each cylinder in the engine during the use of the engine brake, comparing the detected piston acceleration with a predetermined reference value, decreasing exhaust gas back pressure during engine braking if at least one piston is detected with a piston acceleration deviating more than a predefined amount from the predetermined reference value so that the piston acceleration will be falling within the predefined amount from the predetermined reference value.

Abstract: A device for actuating the decompression engine brake in an internal combustion engine provided with hydraulic tappets is described, characterized by: an additional rocker arm (9) for each cylinder, pivoting about an axis (4) common to the rocker arms of the exhaust valves, and suitable to engage with a corresponding additional cam (10) arranged on the cam axis (7) of the cylinders; an actuator system for said additional rocker arm (9), for each cylinder. In the actuator system of said additional rocker arm (9) there is a piston (15) hinged to an end of said rocker arm, said piston (15) being in its turn moved hydraulically or by a mechanical system comprising an additional arm (12) controlled by eccentric cams (13).

Abstract: In an exhaust valve mechanism for an internal combustion engine the main rocker arm is mounted on a rocker arm shaft for normal valve operation via a cam element. A secondary rocker arm is mounted on the shaft for activation of an exhaust brake mode. The activation is achieved through supply of hydraulic pressure to a piston cylinder arrangement acting between the main and secondary rocker arms. A master piston and a slave piston are connected by a hydraulic-link allowing activation by increased hydraulic pressure. When activating the exhaust gas temperature increasing mode, the master piston is moved to an active position for part of its stroke against the force of a first resilient member. When activating the exhaust brake mode, the master piston is moved the full movement of its stroke against the combined forces of the first resilient member and a second resilient member as active position.

Abstract: A control system for engine braking for a vehicle powered by a turbocharged engine uses a supercharger to assist a turbocharger compressor to boost turbocharger air flow into the engine cylinders. An engine driven air pumping device draws ambient air, or alternately exhaust gas through the pump inlet, compresses the air, and delivers the compressed air through the pump outlet to the turbocharger compressor inlet or alternately the turbocharger compressor outlet. The increased air flow into the cylinders and out of the cylinder exhaust valves increases retarding power of the vehicle.

Abstract: 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.