Abstract: A device for controlling cylinder disconnection in internal combustion engines, with a control device which permits in one of its two switching states an actuation of the valve concerned, with transmission devices which, in dependence on the switching state of the control device, transmit the cam stroke to the valve, and with a control unit acting on the control device. This provides a high switch over reliability with only small requirements for the changeover technology used. For this, the device has a data memory for the detection of the time course of the movement behavior of the gas exchange valves of cylinders of the internal combustion engine, and a data processing unit which provides a combination of gas exchange valves into valve groups with regard to a common activation or deactivation.

Abstract: Devices for modifying engine valve lift during an engine valve event are disclosed. In one embodiment, the device comprises: a housing having a hydraulic fluid dump port formed therein; a sleeve slidably disposed in a bore formed in the housing, the sleeve having a cavity formed therein; a piston slidably disposed in the sleeve cavity; and a clip passage formed in the piston, the clip passage in selective communication with the dump port.

Abstract: A device for controlling an opening cross section in the combustion cylinder of an internal combustion engine is provided, the device having a gas exchange valve integrated into the combustion cylinder and having an actuator which drives the valve element to execute a closing stroke and an opening stroke. A valve brake which is active during a residual closing stroke of the valve element is provided for the purpose of reducing the impact velocity of the valve closure member of the valve element on the valve seat in the closing stroke of the valve element. The valve brake has a hydraulic damping element with a fluid displacement volume which flows out through a throttle cross section of a throttle opening, and a control unit for controlling the throttle cross section as a function of the viscosity of the displacement volume.

Abstract: A valve actuator assembly for an engine includes a movable engine valve and a movable spool valve. The valve actuator assembly also includes a driving channel interconnecting the spool valve and the engine valve and a feedback channel interconnecting the spool valve and the engine valve. The valve actuator assembly includes an actuator operatively cooperating with the spool valve to position the spool valve to prevent and allow fluid flow in and out of the driving channel to position the engine valve. The valve actuator assembly further includes an on/off valve in fluid communication with the feedback channel to enable and disable the feedback channel to control motion of the spool valve.

Abstract: Described herein is a multicylinder internal-combustion engine provided with an electronically controlled hydraulic device for controlling variable actuation of the valves of the engine. The final phase of the movement of closing the intake valves is slowed down by a hydraulic braking device of an improved type.

Abstract: A method of correcting a cam phaser system failure including detecting a cam phaser system fault and generating a control signal to correct said cam phaser system fault.

Abstract: In a device for changing the angle of rotation of a camshaft arranged in a cylinder head of an internal combustion engine relative to a drive wheel of the internal combustion engine, wherein a hydraulic adjusting arrangement is arranged between the drive wheel and the camshaft and is connected to a fluid circuit of the internal combustion engine, and wherein the fluid supply to the adjusting arrangement is controlled by an on/off valve, the on/off valve is mounted near the camshaft and is supplied with fluid via the camshaft.

Abstract: An engine valve actuation system is provided. The engine valve actuation system includes an intake valve that is moveable between a first position to prevent a flow of fluid and a second position to allow a flow of fluid. A cam assembly is configured to move the intake valve between the first position and the second position. A fluid actuator is configured to selectively prevent the intake valve from moving to the first position. A source of fluid is in fluid communication with the fluid actuator. A directional control valve is configured to control a flow of fluid between the source of fluid and the fluid actuator. A check valve is disposed between the directional control valve and the source of fluid, only allowing fluid flow from the fluid source to the directional control valve. A bleed orifice may be disposed between the directional control valve and the source of fluid, in parallel with the check valve.

Abstract: An internal combustion engine has a plurality of cylinders containing pistons connected with a crankshaft for transmitting power. The cylinders have closed ends, intake and exhaust ports communicating with the cylinders through the closed ends, valves operable to open and close the ports to air and exhaust flow to and from the cylinders, and a lower end pressure oil lubrication system operative to lubricate at least the cylinders, pistons and crankshaft of the engine. The engine includes hydraulic actuators operable to actuate the valves and forming part of a separate upper end hydraulic oil actuation system operative to selectively supply high pressure hydraulic oil to the hydraulic actuators to actuate the valves in a predetermined manner. Optionally, the hydraulic system may have an oil reservoir within the engine block, such as in the valley between the cylinder banks of a V type engine.

Abstract: A valve for controlling fluids, in particular in an injection valve of an internal combustion engine, including a valve housing (20), in which housing a system region (21) is embodied, in which region a piezoelectric actuator module (22) and a hydraulic coupler module (23) are disposed, which has both an adjusting piston (24), on which the actuator module (22) acts, and an actuating piston (30) that is operatively connected via a hydraulic chamber (29) to the adjusting piston (24) and that is connected to a valve closing member (31) cooperating with a valve seat (37), and the adjusting piston (24) and the actuating piston (30) define the hydraulic chamber (29), and a system pressure for refilling the hydraulic chamber (29) prevails in the system region (21), from which a diversion conduit (38) branches off. The system region (21) is acted upon by a fluid via the diversion conduit (38).

Abstract: A method and assembly for controlling a plunger of a magnetic actuator includes generating a magnetic flux at the plunger that opposes a first bias from a first spring having a first preload. A second spring opposing the first bias is disposed in series communication with the first spring. The second spring has a second preload less than the first preload and is configured to be adjustable to control the amount of magnetic flux needed to overcome a net total preload opposing the magnetic flux. A second magnetic flux higher than the first magnetic flux is generated biasing the plunger to overcome the net total preload from the first and second springs in series communication.

Abstract: An engine valve actuation system may include an actuation assembly having a body, a slidable piston, and first, second, and third chambers defined between the piston and the body. Low pressure and high pressure fluid sources may be included. A first fluid passage may connect the low pressure fluid source to the second chamber. A second fluid passage may connect the high pressure fluid source to the second chamber, and a third fluid passage may connect the high pressure fluid source to the third chamber. A control valve may be connected to the low pressure fluid source, to the high pressure fluid source, and to the first chamber. The control valve may be configured to move between a first position at which the high pressure fluid source is connected to the first chamber, and a second position at which the low pressure fluid source is connected to the first chamber.

Abstract: A hydraulic damper cylinder 270 is provided for an electromagnetic actuated internal combustion engine cylinder valve 20. The damper includes a piston 68 slidably mounted within the damper cylinder 270. The piston 68 bifurcates the cylinder 270 into a first control volume 74 and a second control volume 76. The first and second control volumes are fluidly connected by an inboard flow path 372. Along the extreme ends of travel, the flow path 372 is blocked by the piston 68 and damping occurs through fluid transfer through an outboard flow path 374.

Abstract: The invention relates to an electrohydraulic valve controller for controlling a gas exchange valve in internal combustion engines, having a hydraulically actuatable control valve including a control valve piston which can be acted upon, via electrically actuatable valves, by a hydraulic medium that is under pressure, and a hydraulically acting valve brake is assigned to the control valve piston. The valve brake (46) includes a temperature compensation for the hydraulic medium.

Abstract: A method of providing hydraulic pressure for mechanical work from an engine lubricating system in an internal combustion engine by supplying oil to an engine lubrication gallery for lubricating the engine and at least one variable oil demand accessory. Each of the variable oil demand accessories have individual pressure regulators. The output of the variable displacement pump is regulated to the sum of fluid flow required by the engine lubricating system and the demand for fluid generated by the individual pressure regulators on each of the engine accessories, regardless of the engine output.

Abstract: The invention concerns a control device for adjusting the relative angular position of a driven shaft, particularly a camshaft of an internal combustion engine, said device comprising a drive pinion that is rotatably connected to the shaft, an adjusting element (1) for the angular adjustment of the drive pinion relative to the shaft, two chambers (2, 3) that are alternately supplied with hydraulic fluid and a control valve (6) for actuating the adjusting element (1), said control valve being connected to the chambers (2, 3) of the adjusting element (1) through pressure medium channels (4, 5). The control valve (6) comprises a valve body (7) that has two working connections A and B for the pressure medium channels (4, 5), a delivery connection P for the supply of hydraulic fluid and a discharge connection T for the discharge of hydraulic fluid, and the control valve (6) further comprises a sliding valve control piston (8) for setting different hydraulic resistances W between the individual connections.

Abstract: An apparatus for controlling gas exchange valves of an internal combustion engine having hydraulic valve actuators each assigned to one gas exchange valve, with one adjusting piston acting on the gas exchange valve and two hydraulic work chambers defined by the adjusting piston the first work chamber acting on the gas exchange valve in the closing direction being constantly filled with fluid that is under pressure, and the second work chamber acting on the gas exchange valve in the opening direction can be filled with and relieved of fluid that is under pressure in alternation via a first and second electrical control valve. Two valve actuators are each triggered in alternation by the same first and the same second control valve, and the switchover of the control valves is performed during the closing state of the two gas exchange valves actuated by these valve actuators.

Abstract: A valve actuator assembly for an engine includes a movable engine valve and a movable spool valve. The valve actuator assembly also includes a driving channel interconnecting the spool valve and the engine valve and a first feedback channel and a second feedback channel interconnecting the spool valve and the engine valve. The valve actuator assembly includes an actuator operatively cooperating with the spool valve to position the spool valve to prevent and allow fluid flow in and out of the driving channel to position the engine valve. The valve actuator assembly further includes a first on/off valve and a second on/off valve in fluid communication with the first feedback channel and the second feedback channel to enable and disable the first feedback channel and the second feedback channel, whereby the first on/off valve and the second on/off valve control motion of the spool valve.

Abstract: The invention relates to a hydraulic actuator for actuating a gas exchange valve (1) of an internal combustion engine, which valve is especially closed by the effect of a spring. The actuator is configured by a feed pump (6) with intermittent and thus variable delivery. The feed pump (6) has a high frequency and can be equipped for this purpose with piezoelectric, magnetorestrictive and/or electrochemical actuators as the feed elements. Optionally, the feed pump (6) can be operated with a stop valve (7) that is disposed downstream of the gas exchange valve (1) and that is controlled or regulated depending on the feed pump.

Abstract: A lost motion assembly for a valve of an internal combustion engine includes a cam, a cam piston which is spring biased to follow motion of the cam, a valve piston operatively engaged with a poppet valve, and an auxiliary piston. The cam piston, valve piston and auxiliary piston are in continuous contact with a fluid in an enclosed control chamber having a fixed volume, such that rotation of the cam causes displacement of the cam piston into the control chamber, which causes a corresponding displacement of at least one of the valve piston and auxiliary piston while the volume of fluid in the control chamber remains substantially constant.

Abstract: An apparatus for deactivating an engine valve has an accumulator sleeve slidably retained in an engine block and biased toward a lower chamber in fluid communication with an interior of the sleeve. A follower piston slides in the sleeve in contact with a lobe of a can. An upper piston slides in an upper chamber in contact with a pushrod. A fluid passage connects the lower chamber and the upper chamber. A normally open spool valve in the fluid passage includes a control spool for opening and closing the passage. Another passage connects the lower chamber and one end of the control spool. A spring chamber provides fluid to an opposite end of the control spool through a control valve from a source of pressurized fluid.

Abstract: An electrohydraulic valve actuator assembly for an engine includes a movable engine valve, a movable spool valve, and a driving channel interconnecting the spool valve and the engine valve. The electrohydraulic valve actuator assembly includes an actuator operatively cooperating with the spool valve to position the spool valve to prevent and allow fluid flow in and out of the driving channel to position the engine valve. The electrohydraulic valve actuator assembly further includes a mechanical feedback interconnecting the engine valve and the spool valve to control the position of the spool valve.

Abstract: A passive valve assembly for controlling the flow into or out of chamber (3) through a port (4). The valve assembly comprises a valve element (5) arranged to open in the direction of flow through the port. The valve element (5) has a piston (9) which is reciprocable in a cylinder (10) containing gas. On opening of the valve, gas is compressed in a first chamber (11) of the cylinder (10), and this energy of compression is used to reverse the direction of the valve element (5) and return it to its seat.

Abstract: Lost motion systems and methods for providing engine valves with variable valve actuation for engine valve events are disclosed. The system may include a master piston hydraulically linked to a slave piston, and a dedicated cam operatively connected to the master piston. The slave piston may be disposed substantially perpendicular to the master piston in a common housing. The slave piston is adapted to actuate one or more engine valves. The slave piston may incorporate an optional valve seating assembly into its upper end. A trigger valve may be operatively connected to the master-slave hydraulic circuit to selectively release and add hydraulic fluid to the circuit.

Abstract: A valve actuator for actuating a gas exchange valve of an internal combustion engine, having a sleeve-shaped positioning piston, which is connected to a valve shaft, having at least two shell-shaped wedge parts, enclosing a shaft end of the valve shaft, on whose radial outer peripheral surface a section shaped like a conical casing is implemented and which are axially connected on their inner side to the shaft end in a form-locked and rotatable manner, the valve actuator having a separate threaded sleeve, which has a threaded connection to the positioning piston or a component connected to the positioning piston and also axially clamps the wedge parts to a conical clamp sleeve via their section shaped like a conical casing.

Abstract: A device and control method for actuating valves of a motor vehicle internal combustion engine including at least a controlled hydraulic actuator actuating the associated valve that is provided in the form of a cylinder. A mobile piston connected to the valve delimits two opposite hydraulic pressure chambers each supplied with an incompressible fluid and pressure regulated by a control unit such that the pressure prevailing in one of the chambers is alternately higher/lower than that which prevails in the other chamber to actuate the valve. Each pressure chamber of the cylinder is capable of communicating with a corresponding actuating hydraulic pressure source, which includes a pneumatic return mechanism for the fluid.

Abstract: A variable camshaft timing mechanisms having a vane/housing format is provided. Working hydraulic chambers are created by imposing either single or multiple vanes of a rotor attached to the camshaft into a cavity in a housing that is attached to the camshaft sprocket. Fluid is allowed to normally exhaust from the hydraulic chamber during normal phasing until the rotor nears the end of its travel.

Abstract: An apparatus for controlling gas exchange valves includes at least one valve positioner, associated with a gas exchange valve, and a pressure supply device which supplies the valve positioner with a fluid under high pressure. The valve positioner encompasses a working cylinder having a positioning piston, coupled to the gas exchange valve, which delimits an upper pressure space for opening the valve and a lower pressure space for closing the valve, and encompasses a control valve controlling the hydraulic pressure in the pressure spaces. In order to reduce the manufacturing costs and electrical energy demand of the apparatus, the upper pressure space is connected directly, and the lower pressure space via a restrictor throttle, to the pressure supply device; and the control valve is connected to the lower pressure space and to a relief line. Depending on the switch position, the control valve additionally connects the lower pressure space to the relief line or blocks it off from the relief line.

Abstract: An integrated hydraulic valve actuator for use in a camless internal combustion engine. The valve actuator includes a separate bolt-on housing defining a through opening receiving a cylindrical liner. The liner internally defines an internal cylinder providing a riding surface, which coaxially surrounds an outer surface of a tubular boost piston. The boost piston defines an inner cylinder, which provides a riding surface for a drive piston fitted within the inner cylinder of the boost piston. The pistons are axially reciprocable within the liner cylinder. A piston position sensor extends radially into the housing and engages a cam on the drive piston to relay the position of the drive piston to a controller. The actuator is preassembled and the housing is attached to an engine cylinder head or cylinder head supply manifold to operate an associated exhaust or intake valve.

Abstract: An hydraulically controlled actuator for activating a valve, especially for activating a gas-exchange valve in a combustion cylinder of an internal combustion engine, which includes two fluid-filled pressure chambers having controllable chamber volumes and a movable operating piston which delimits the pressure chambers by piston sides facing away from one another, the operating piston acting upon the valve and having an effective closing area acted upon by fluid pressure in the pressure chambers to close the valve and an effective opening area acted upon by the fluid pressure to open the valve. To influence the kinematics of the opening and closing movement of the valve, the operating piston is such that the surface area of at least one of the two effective areas changes along the sliding path of the operating piston.

Abstract: A system and method for actuating at least one engine valve in an internal combustion engine to produce an engine valve event is disclosed. The system of the present invention may comprise: means for imparting motion to the at least one engine valve for producing the engine valve event; primary means for transmitting the motion from the motion imparting means to the at least one engine valve; and auxiliary means for transmitting the motion from the motion imparting means to the at least one engine valve. The auxiliary means may actuate the at least one engine valve only when the primary means is shut-off or fails.

Abstract: An internal combustion engine includes a hydraulic system with a hydraulic pump. A lubricant system for moving parts of the engine is also provided, which includes a lubricant pump. To enable making the engine smaller, it is proposed that the hydraulic pump is connected to the lubricant system in such a way that it can be lubricated by the lubricant.

Abstract: A gas exchange valve device for an internal combustion engine is provided with a hydraulic apparatus which includes a fluid circuit and at least one pressure reservoir connected to the fluid circuit and containing piston prestressed by a device, and also includes a controllable actuating device. A gas exchange valve is also provided, whose valve element is acted on by the actuating device. In order to achieve a simpler design of the gas exchange valve device the pressure reservoir is disposed so that in an approximately unpressurized state of the pressure reservoir, its piston at least indirectly locks the valve element of the gas exchange valve in an essentially closed position.

Abstract: A valve actuator assembly for an engine includes a movable engine valve, a movable first spool valve, and a movable second spool valve. The valve actuator assembly also includes a driving channel interconnecting the second spool valve and the engine valve, an intermediate channel interconnecting the first spool valve and the second spool valve, and a feedback channel interconnecting the second spool valve and the engine valve. The valve actuator assembly includes an actuator operatively cooperating with the first spool valve to position the first spool valve to prevent and allow fluid flow in and out of the second spool valve and the driving channel to position the engine valve. The valve actuator assembly further includes an on/off valve in fluid communication with the feedback channel to enable and disable the feedback channel to control motion of the second spool valve.

Abstract: A valve actuator assembly for an engine includes a movable engine valve, a movable first spool valve, and a movable second spool valve. The valve actuator assembly also includes an intermediate channel interconnecting the first spool valve and the second spool valve, and a driving channel, a first feedback channel, and a second feedback channel interconnecting the second spool valve and the engine valve. The valve actuator assembly includes an actuator operatively cooperating with the first spool valve to position the first spool valve to prevent and allow high pressure fluid flow to the second spool valve and the driving channel to position the engine valve.

Abstract: An engine valve actuator is provided. The actuator includes an actuator housing that defines a tank adapted to store a supply of fluid and a bore in fluid communication with the tank. A piston is slidably disposed in the bore of the actuator housing. The piston is adapted to move between a first position and a second position where the piston selectively engages an engine valve. A mechanical biasing element acts on the piston to move the piston towards the second position. A control valve is disposed between the tank and the bore in the actuator housing. The control valve is moveable between a first position where fluid is allowed to flow between the tank and the bore and a second position where fluid is prevented from flowing between the bore and the tank to trap fluid in the bore. The trapped fluid prevents the piston from moving with respect to the actuator housing to thereby prevent the engine valve from moving to a closed position.

Abstract: A hydraulically controlled actuator for actuation of an exhaust-side gas exchange valve of an internal combustion engine, containing a control piston that is displaceable within a cylinder and, with piston sides facing away from one another, delimits pressure chambers, of which the one pressure chamber impinges upon the gas exchange valve in the closing direction and the other pressure chamber impinges upon the gas exchange valve in the opening direction. In the actuator is provided at least one spring element, which can be brought into a preloaded state by the control piston moving in the closing direction of the gas exchange valve, and whose stored potential energy accelerates the gas exchange valve in the opening direction at least at the beginning of an opening phase, is provided. This results in a reduction in the energy expended in the context of valve actuation.

Abstract: A control system adapted to control an actuator between extended and retracted positions has a fluid control valve connected to the actuator a source of high pressure fluid and a reservoir. The fluid control valve is movable between a first position at which the actuator is connected back to the fluid reservoir adapted and a second position operable to connect the actuator to a high pressure actuation fluid source. An electronic control module is connected in control communication with the fluid control valve and adapted to automatically generate a control signal to position the control valve at the second position in response to an elapsed time being passed at which the fluid control valve is at the first position is greater than a predetermined time.

Abstract: The invention concerns a control device for adjusting the relative angular position of a driven shaft, particularly a camshaft of an internal combustion engine, said device comprising a drive pinion that is rotatably connected to the shaft, an adjusting element (1) for the angular adjustment of the drive pinion relative to the shaft, two chambers (2, 3) that are alternately supplied with hydraulic fluid and a control valve (6) for actuating the adjusting element (1), said control valve being connected to the chambers (2, 3) of the adjusting element (1) through pressure medium channels (4, 5). The control valve (6) comprises a valve body (7) that has two working connections A and B for the pressure medium channels (4, 5), a delivery connection P for the supply of hydraulic fluid and a discharge connection T for the discharge of hydraulic fluid, and the control valve (6) further comprises a sliding valve control piston (8) for setting different hydraulic resistances W between the individual connections.

Abstract: An oil supply structure for an engine cylinder head is disclosed. In an engine having a variable valve timing apparatus utilizing oil pressure as an operational power source to smoothly supply lubricating oil for the cylinder head and an operational oil for the variable valve timing apparatus in a clean state, the arrangement of passages allows for ease of installation and maintenance of the components of the oil temperature sensor and oil control valve comprising the variable valve timing apparatus.

Abstract: A hydraulic manifold assembly for variable actuation of engine valves. First and second plates have portions of flow passages integrally molded therein. The plates are formed preferably by injection molding of a suitable polymer, for example, glass-filled nylon, and are joined together as by cementing or preferably by fusion welding (vibration welding) along mating surfaces to form the full pattern of flow passages. This method of forming the manifold obviates the need for separate fasteners to connect the plates and for internal seals to form the flow passages. The assembly further comprises a retainer for retaining a plurality of individual solenoid-actuated valves in sockets formed in the plates. Preferably, the retainer is formed to function simultaneously as a positive crankcase ventilation (PCV) baffle that attaches to the plates via integrally molded releasable snap tabs.

Abstract: An oil control valve (60) that controls a valve timing gear mounted on a cylinder head (1) of an internal combustion engine. The oil control valve includes a housing (3) with plural oil lines; a spool type valve (5) that moves in the housing to open and close the oil lines; and a solenoid (31) having a metal case (33) and driving the spool type valve. And this housing (3) is mounted on the cylinder head (1). At least a part of the metal case (33) passes through a through hole (183) through a cylinder head cover (18) covering the cylinder head (1) and is disposed outside the cylinder head cover (18). As a result, all parts of the oil control valve (60) are disposed inside the head cover (18), and even in case of oil leakage, the oil does not leak out of the engine.

Abstract: In a Diesel engine with variably actuated valves, the cam controlling each inlet valve is shaped to provoke the opening of the respective inlet valve during the engine's normal exhaust phase and thus realize exhaust gas recirculation within the engine, due to the fact that during the normal exhaust phase, part of the exhaust gas passes from the cylinder into the inlet port, from where it returns to the cylinder during the next induction phase, while part of the exhaust gas that had previously passed into the exhaust port returns to the cylinder during the induction phase due to the additional opening of the exhaust valve, in consequence of which the exhaust gas charges that return to the cylinder are subjected to further combustion in the next engine cycle.

Abstract: An engine valve actuation system is provided. The system includes an engine valve moveable between a closed position and an open position. A spring is operatively connected to the engine valve to bias the engine valve towards the closed position. An actuator is operatively connected to the engine valve and is operable to selectively engage the engine valve to prevent the engine valve from returning to the closed position and to release the engine valve to allow the engine valve to return to the closed position. A sensor is configured to provide information related to the operation of the actuator. A controller is configured to transmit a signal to the actuator to engage the engine valve to prevent the engine valve from returning to the closed position and to release the engine valve to the allow the engine valve to return to the closed position.

Abstract: A deactivation hydraulic valve lifter which includes an elongate lifter body having a substantially cylindrical outer surface and an inner wall, the inner wall defining at least one annular pin chamber therein. The outer surface defining at least one annular groove in fluid communication with a high-pressure oil gallery of an engine, the lifter body having a lower end configured for engaging cam of the engine.

Abstract: An engine has a cylinder head having a first surface and a second surface spaced from the first surface. A valve is moveably connected to the cylinder head. A rocker arm is connected to the valve, and a rocker shaft having a first location spaced a maximum distance from the cylinder head is connected to the rocker arm. A support member has and an actuator fluid passage network. The actuator fluid passage network defines a volume. The support member is connected to the cylinder head and is positioned such that a majority of the volume of the actuator fluid passage network is between the first location of the rocker shaft and the second surface of the cylinder head.

Abstract: A valve actuator assembly for an engine includes a movable engine valve and a movable spool valve. The valve actuator assembly also includes a driving channel interconnecting the spool valve and the engine valve and a feedback channel interconnecting the spool valve and the engine valve. The valve actuator assembly includes an actuator operatively cooperating with the spool valve to position the spool valve to prevent and allow fluid flow in and out of the driving channel to position the engine valve. The valve actuator assembly further includes an on/off valve in fluid communication with the feedback channel to enable and disable the feedback channel to control motion of the spool valve.

Abstract: A valve actuator for controlling a valve between an open and a closed disposition includes couplings to a source of fluid under pressure and a reservoir at substantially ambient pressure. A control fluidly coupled to the source of fluid under pressure and to the reservoir for controlling presenting fluid at selected pressure to affect a reciprocatable component, the reciprocatable component being operably coupled to the valve for shifting the valve between the open and the closed disposition. And, positively, hydraulically shifting the valve between the open and the closed disposition. A method of valve actuation is also included.

Abstract: A valve actuator assembly for an engine includes a movable engine valve, a movable first spool valve, and a movable second spool valve. The valve actuator assembly also includes a driving channel interconnecting the second spool valve and the engine valve, an intermediate channel interconnecting the first spool valve and the second spool valve, and a feedback channel interconnecting the second spool valve and the engine valve. The valve actuator assembly includes an actuator operatively cooperating with the first spool valve to position the first spool valve to prevent and allow fluid flow in and out of the second spool valve and the driving channel to position the engine valve. The valve actuator assembly further includes an on/off valve in fluid communication with the feedback channel to enable and disable the feedback channel to control motion of the second spool valve.

Abstract: A valve actuator assembly for an engine includes a movable engine valve and a movable spool valve. The valve actuator assembly also includes a driving channel interconnecting the spool valve and the engine valve and a first feedback channel and a second feedback channel interconnecting the spool valve and the engine valve. The valve actuator assembly includes an actuator operatively cooperating with the spool valve to position the spool valve to prevent and allow fluid flow in and out of the driving channel to position the engine valve. The valve actuator assembly further includes a first on/off valve and a second on/off valve in fluid communication with the first feedback channel and the second feedback channel to enable and disable the first feedback channel and the second feedback channel, whereby the first on/off valve and the second on/off valve control motion of the spool valve.