Abstract: An apparatus for zero voltage switching is disclosed. A system and method also perform the functions of the apparatus. The apparatus includes an MCT region module that defines a minimum current trajectory (“MCT”) for operation between a maximum positive power output to a maximum negative power output of a bidirectional DC-to-DC converter. The converter includes a dual active bridge series resonant converter. The MCT defines a boundary between a zero voltage switching (“ZVS”) region and a hard switching region. The apparatus includes an offset module that defines an offset to the MCT, the offset in the ZVS region, and an MCT control module that adjust switching of switches of the converter to maintain operation of the converter in the ZVS region between the maximum positive power output to a maximum negative power output along a trajectory defined by the MCT and the offset.

Abstract: An electromagnetically actuated valve includes at least one sleeve, a magnet core arranged in a fixed manner in the at least one sleeve, a magnet armature configured to actuate a valve element and arranged so as to be axially movable, and an elastically deformable flat spring element held in a clampable manner between a core end face of the magnet core facing the magnet armature and an armature end face of the magnet armature facing the magnet core. The spring element is configured to form at least one contact point with the armature end face and the core end face. The core end face defines a stepped configuration in a radial extent having at least two successive steps.

Abstract: The present invention relates to a camshaft (1) for an internal combustion engine with a drive wheel (4) arranged on a longitudinal end side, in particular with a chain wheel or belt pulley, and with at least one first bearing (2) arranged in the region of the drive wheel (4) and a second bearing (3) arranged in the further course of the camshaft (1). Here it is substantial to the invention that at least the first bearing (2) is designed as a rolling bearing and has an inner diameter of 24 mm<di<30 mm, wherein the inner diameter di is larger than the outer diameter da of the camshaft (1) on the second bearing (3). Because of this, the camshaft (1) can be configured more compact and lighter.

Abstract: A plunger is formed of a soft magnetic material to have one end connected a regulation pin. A permanent magnet is affixed to a stationary portion, which is stationary relative to the plunger, to attract the plunger in a retreated direction. A coil generates a magnetic flux in an opposite direction of the permanent magnet to reduce a magneto attraction force, which attracts the plunger. A spring biases the regulation pin in an advanced direction. The spring applies a biasing force to the regulation pin to move the regulation pin in the advanced direction when electricity is supplied to the coil to reduce the magneto attraction force of the permanent magnet. A magnetism detection unit is located on a magnetic circuit, which conducts a magnetic flux generated by the permanent magnet and the coil, to detect a magnetic flux density.

Abstract: Methods and systems for purging a hydrocarbon trap in an engine intake in a vehicle are disclosed. In one example approach, a method comprises during an engine off condition, operating a pump in a purge line coupled to a fuel vapor canister in an emission control system to deliver fuel stored in a hydrocarbon trap in an intake of the engine to the fuel vapor canister.

Abstract: A system according to the principles of the present disclosure includes a valve control module and a fault detection module. The valve control module controls a valve actuator to actuate a valve of an engine from a first lift position to a second lift position that is different from the first lift position. The valve includes at least one of an intake valve and an exhaust valve. The fault detection module detects a fault in at least one of a valve lift sensor and the valve actuator based on input received from the valve lift sensor when the valve is adjusted to the first lift position and when the valve is adjusted to the second lift position.

Abstract: A combustion-powered fastener-driving tool includes a combustion-powered power source having a combustion chamber, a reciprocating piston and driver blade, and a valve sleeve reciprocable relative to the power source between a rest position and a firing position. The valve sleeve partially defines the combustion chamber. A lockout device is in fluid communication with the combustion power source and includes a reciprocating gas piston connected to a latch in operational proximity to the valve sleeve. The lockout device is configured such that upon combustion in the combustion chamber, gas from the combustion engages the gas piston and moves the latch to an engaged position in which the valve sleeve is prevented from moving to the rest position.

Abstract: A device for correcting injector characteristics includes: an injector-characteristic detection unit that outputs a selection signal by detecting drive characteristics of injectors in response to a selection control signal; a selection control unit that outputs the selection control signal for selecting a factor for deviation correction to the injector-characteristic detection unit; a selection confirmation unit that confirms a variation value of the factor corresponding to the selection signal; a deviation correction unit that calculates a deviation compensation value corresponding to the injector characteristics in response to an output signal of the selection confirmation unit, and thus output a correction signal; a control unit that generates a correction clock in response to the correction signal; and an output drive unit that controls driving of the injectors in response to the correction clock.

Abstract: A method for operating an internal combustion engine (4) with an electrohydraulic valve train (1) for variable-lift drive of a gas exchange valve (3), including a camshaft (6) and a hydraulic system arranged in a drive path between the camshaft and the gas exchange valve, said hydraulic system being connected to a pressure medium supply (14) of the internal combustion engine, a first hydraulic piston (8) which is driven by a cam (5) of the camshaft and a second hydraulic piston (9) which drives the gas exchange valve in an opening direction, a variable-volume pressure chamber (10) which is delimited by the hydraulic piston and a control channel (12) which connects the pressure chamber to a pressure relief chamber (11), an electrically actuated hydraulic valve (15) which is arranged in the control channel and which, in an open position, permits a flow of hydraulic medium through the control channel and, in a closed position, blocks a flow of hydraulic medium through the control channel, and an electronic contr

Abstract: An engine start control device includes: a control valve which adjusts a gas flow rate of a gas channel provided so as to bypass a throttle valve of an engine; a starter motor capable of driving a crankshaft of the engine; a control unit which controls an opening degree of the control valve and a current supply to the starter motor; and a latch circuit which holds a command for current control from the control unit to the starter motor, wherein the control unit performs the control so as to cause the current supply to the starter motor to start after the opening degree of the control valve reaches a target opening degree for an engine start time, and even when the control unit is reset, the latch circuit continues the current supply to the starter motor according to the command for current control that the latch circuit keeps holding.

Abstract: A camshaft adjuster for an internal combustion engine is composed of an adjusting gear designed as a triple-shaft gear, with a drive wheel which is driven from the internal combustion engine and via which the drive torque for the camshaft is introduced, of a gear output coupled fixedly in terms of rotation to the camshaft, and of a gear input wheel which is coupled to a drive motor and via which the adjusting torque causing the relative rotation between the drive wheel and gear output is introduced into the adjusting gear. The cam adjuster includes a failsafe mechanism which causes blocking of the adjusting gear and which, in the event of the absence of an adjusting torque to be introduced via the gear input wheel, acts upon a gear element located between the drive wheel and gear output.

Abstract: A bistable electromagnetic actuating apparatus (1) having an actuating element (2), which forms an engagement region (4) at the end and can be moved axially between two end positions, in particular for engaging in a control groove in a cam of an internal combustion engine, and having a coil device (11) which is provided in a stationary manner relative to the actuating element (2) and is designed to exert a force on said actuating element, wherein the actuating element (2) has permanent magnets (5) which are designed to interact with a core region (3) which is provided in a stationary manner relative to the actuating element (2), and wherein the coil device (11) is designed to generate a counterforce, which counteracts a retaining force of the permanent magnets (5) and releases said permanent magnets from the core region (3), in response to an electronic actuation signal, and wherein a spring is arranged such that it applies a spring force to the actuating element (2) in an axial direction which faces away fro

Abstract: A linear variable differential transformer (LVDT) for monitoring engine valve position is disclosed. The system includes a valve guide having an elongated recess through it. The engine valve has a valve head and a valve stem with two adjacent materials having different magnetic properties meeting at an interface. The valve stem fits and moves linearly within the valve guide, and the valve head closes an engine combustion chamber. It also includes monitoring coils within the valve guide that create a signal related to the position of the interface within the valve guide. An engine control unit (ECU) is coupled to the monitoring coils and receives and analyzes the signal from the monitoring coils to determine operation of the valve.

Abstract: A method and a control unit are disclosed for controlling a single-cylinder or multiple-cylinder internal combustion engine having at least one fuel injector per cylinder, at least one camshaft for actuating inlet valves and/or outlet valves, and having a control unit which controls the fuel injectors in such a way that they inject in each case one fuel pre-injection per cylinder during a starting phase of the internal combustion engine. In order to make an improved pre-injection strategy possible during the starting phase, according to the invention at least one cylinder pressure signal which is supplied by a cylinder pressure sensor for measuring the pressure in a cylinder is evaluated with regard to interference signals, and the evaluation result is taken into consideration at least during the starting phase in a determination of the camshaft angle.

Abstract: A method for controlling an electric variable cam timing (VCT) actuator is disclosed. The method includes during engine shutdown, adjusting camshaft position with an electric VCT actuator to a target starting location, applying a first current to the electric VCT actuator to maintain the target starting location, and during engine startup before camshaft position feedback becomes available, applying a second current to the electric VCT actuator to maintain the target starting location.

Abstract: An engine control system for a vehicle includes a pressure determination module, an adjustment determination module, a target determination module, and a pump control module. The pressure determination module determines a first pressure for a hydraulic fluid provided to fully flexible intake and exhaust valve actuators of an engine. The adjustment determination module determines a pressure adjustment for the first pressure based on a pressure within a cylinder. The target determination module determines a target pressure for the hydraulic fluid based on the first pressure and the pressure adjustment. Based on the target pressure, the pump control module controls a hydraulic fluid pump for an opening timing of an exhaust valve of the cylinder.

Abstract: An actuator for axially displacing an object includes an actuator piston disc and an actuator piston rod, which together form an actuator piston, a cylinder volume, the actuator piston disc dividing the cylinder volume into a first part and second part and being displaceable in the cylinder volume between an inactive and active position, a pressure fluid circuit arranged for controllable fluid communication with the first part, and a first hydraulic circuit including a liquid-filled space, the actuator piston rod being disposed to be axially displaced in relation to the liquid-filled space in connection with axial displacement of the actuator piston disc in the cylinder volume. The actuator piston includes a second hydraulic circuit, the liquid-filled space being in fluid communication with an inner cavity in the second hydraulic circuit when the actuator piston disc is in the inactive position, the inner cavity partly being delimited by a positioning piston.

Abstract: An electric control device includes: a cam having a variable distance between an outer periphery and a center; a control shaft having one end, which contacts the outer periphery of the cam, and displaceable according to a rotation of the cam to adjust a valve lift amount; a motor rotating the cam; an angle detector detecting a rotation angle of the cam; and a controller. The cam includes multiple steps arranged on the outer periphery. The controller controls the rotation of the cam through the motor to match a detection angle of the angle detector with a target angle corresponding to a target valve lift amount. The controller stops rotating the cam through the motor when a difference between the detection angle and the target angle exceeds a first threshold, and the target angle corresponds to one of the steps.

Abstract: A variable valve actuation system in one form includes a rocker coupled with a valve stem at one end and a cam follower at the other end. The rocker is operable to rotate about a fixed axis and the cam follower includes a set of lower rollers operable to follow one cam lobe and an upper roller operable to follow another cam lobe. A leaf spring can be used to couple the cam follower with the rocker. A cam shaft can have a nested configuration that includes an inner shaft, an intermediate tube, and an outer tube. Cam lobes can be fastened to the cam shaft by fastening through each of the inner shaft, intermediate tube, and outer tube. The cam lobes can be attached by at least two devices inserted from either side of the cam shaft and that are not inserted at least through the inner shaft.

Abstract: A method for controlling the movement of a component that moves towards a position defined by a limit stop in an internal combustion engine; the control method comprises the steps of detecting, by means of at least one acoustic microphone, the intensity of the microphonic signal generated by the impact of the component against the limit stop; and determining the impact instant and/or the impact speed of the component against the limit stop by analyzing the intensity of the microphonic signal generated by the impact.

Abstract: A method monitors an electromagnetic hydraulic valve for controlling a hydraulically adjustable valve gear of a reciprocating piston engine. The hydraulic valve includes an electromagnetic coil and a moving armature configured to connect a control port hydraulically to a high-pressure port or a low-pressure port, depending on an energization of the coil. The method includes detecting a movement of the armature, using a control unit, in response to an energization of the coil based on a mutual induction in the coil and identifying a defect, using the control unit, if the expected mutual induction does not occur.

Abstract: A micro-fluidic system comprising a micro-fluidic channel, which has a wall provided with a hole; and a closing element, which is adapted to cooperate with a partition arranged within the micro-fluidic channel in the area of the hole to isolate or connect two segments of the channel; the closing element is made of a photoresist material, in particular a material obtained by the polymerisation of a photopolymerable material.

Abstract: A fluid working machine comprises a working chamber of cyclically varying volume, a high pressure manifold, and an actuated high pressure valve for regulating the flow of fluid between the working chamber and the high pressure manifold. The actuated high pressure valve comprises a moveable valve member, operable between a closed position and at least one open position. A controllable opening mechanism provides an active urging force to urge the moveable valve member from the said closed position towards at least one said open position, the volume of the working chamber varying between a maximum volume and a minimum volume. The controllable opening mechanism provides the active urging force more than once while the volume of the working chamber is intermediate the maximum of chamber volume and the minimum of chamber volume.

Abstract: A rotary electromagnetic actuator is provided which is suitable for opening and closing a valve for example. The actuator comprises a rotor (10), a stator (16), and a biasing arrangement (20, 100, 102, 104, 106) for applying a torque to the rotor during at least part of its rotation. A plurality of stable rest positions (200; 316, 318; 400) for the rotor are defined by forces acting on the rotor and the actuator is controllable to move the rotor from one stable rest position to another. The torque applied by the biasing arrangement varies with the rotational position of the rotor such that at a primary rest position and at least a second rest position, it is sufficiently low to enable selection of those positions, and then it increases beyond the second rest position.

Abstract: A reactor with minimal dead volume especially suited to reverse-flow applications comprises: a) a reactor body; b) a first head engaged with said reactor body; c) a first conduit extending from outside said head to at least partially through said head; and d) a first valve in flow communication with said first conduit controlling fluid flow along a flow path extending from the first valve and through the reactor body. The reactor is especially suited for use in a process for rapid stream-switching of at least two streams in a reverse-flow reactor.

Abstract: A camless engine operating system that includes an inlet valve switch configured to detect rotational movement of an inlet valve power disc and to output an inlet actuator voltage. A voltage level of the inlet actuator voltage is synchronous with the rotational movement of the inlet valve power disc. An inlet valve is movable to open and close an intake port of a combustion chamber. An inlet valve mechanical force moves the inlet valve to open the intake port. An inlet actuator is configured to exert the inlet valve mechanical force onto the inlet valve. The inlet actuator voltage received by the inlet actuator controls the inlet actuator to exert the inlet valve mechanical force onto the inlet valve.

Abstract: A system and method comprising four valves per cylinder of a multi-cylinder engine is provided to control cylinder intake and exhaust valves independently from other cylinders in response to engine operating conditions. The engine valve deactivation system for the engine may comprise two or more cylinders wherein each cylinder has two exhaust valves and two inlet valves. The system and method may allow for cylinder deactivation and/or high swirl to both be delivered.

Abstract: An intake apparatus of an engine includes: a first intake passage supplying fresh air to a cylinder; a second intake passage arranged near the first intake passage, and supplying fresh air to the cylinder; a first intake valve opening and closing the first intake passage at an aperture of the first intake passage; a second intake valve opening and closing the second intake passage at an aperture of the second intake passage. An opening timing of the first intake valve of the intake apparatus advances relative to a top dead center, and a valve lift amount of the first intake valve differs from that of the second intake valve, and there is a period while the valve lift amount of the first intake valve is larger than that of the second intake valve, in an intake stroke.

Abstract: A solenoid valve module includes a first solenoid valve having a first solenoid portion and a first valve body and a second solenoid valve having a second solenoid portion and a second valve body. The first valve body and the second valve body are integrally formed by a solenoid housing. The solenoid valve module is secured to a surface of an engine to provide hydraulic control for an engine component.

Abstract: The invention relates to an electromagnetic actuating device (1) for a camshaft adjustment device of an internal combustion engine of a motor vehicle, with an elongated actuating element (2) forming an engagement region on the end side and movable by the force of a coil device (29) provided in a stationary manner, which actuating element preferably has in parts a cylindrical covering contour and penetrates a cut-out (8) in permanent magnet means (6) arranged on the shell side, which are constructed for cooperating with a stationary core region (5) comprising a core body (15), and which actuating element lies in a switching position with a contact surface (11), on the end side on the actuating element side, against a contact surface (10) on the core region side.

Abstract: An actuator unit (1) of a cam shifting system, which actuator unit is mountable on an internal combustion engine or a component thereof and has at least one actuator pin (5) for moving shifting cam units of the cam shifting system into different axial positions by means of at least one shift groove formed on the periphery of the shifting cam units and cooperating with the actuator pin (5). The actuator pins (5) are spring-loaded in a direction toward the shifting cam unit, operable by a solenoid unit, and slidably supported in a housing (2) of the actuator unit (1). The housing (2) of the actuator unit (1) is provided with at least one enlargement in each inner surface facing an actuator pin (5).

Abstract: In a valve timing control system of an internal combustion engine employing both an electric-motor-driven intake valve timing control device for changing intake valve timing and an electric-motor-driven exhaust valve timing control device for changing exhaust valve timing, the intake valve timing control device includes a less-friction roller speed reducer having a toothed gear and configured to transmit torque by repeated relocations of each of rollers rolling and relocating from one of two adjacent teeth of the toothed gear to the other. In contrast, the exhaust valve timing control device includes a planetary-gear speed reducer having a friction greater than a friction of the roller speed reducer and configured to transmit torque by meshed-engagement of toothed gears in mesh with each other.

Abstract: A camshaft adjuster (3), comprising a camshaft axis of rotation (D) and an electromagnetic multi-tappet actuating device (4) having at least two electromagnetic drive units, which for exerting an actuating force on a corresponding number of elongated tappet units (9, 10, 11) which are mounted axially parallel to one another, each defining a tappet longitudinal center axis (A1, A2, A3) arranged perpendicularly to the camshaft axis of rotation (D) are activatable, in order to engage with the tappet units (9, 10, 11) in shifting grooves (8) of an adjustable cam piece (7), wherein the drive units each on a facing acting end on one of the associated tappet units (9, 10, 11) form an acting surface that is moveable in an actuating direction of the drive units and an end face on the acting side facing away from the respective associated shifting groove (8) of a respective one of the tappet units (9, 10, 11) interacts with the acting surface, wherein at least one of the tappet units (9, 10, 11) is arranged relative to

Abstract: A method for determining a closing time of a valve having a coil drive, in particular a direct injection valve for an engine of a motor vehicle, has the steps: (a) switching off a current flow through a coil (L_inj) of the coil drive, so that the coil (L_inj) is depowered, (b) capturing a time curve (110) of a voltage induced in the non-powered coil (L_inj), wherein the induced voltage is generated by decaying eddy currents in a magnetic circuit of the coil drive and by a motion of the armature relative to the coil (L_inj), (c) evaluating the captured time curve (110) of the voltage induced in the coil (L_inj), and (d) determining the closing time based on the evaluated time curve (110). A corresponding device and a computer program for determining the closing time of a valve with a coil drive can be provided accordingly.

Abstract: Methods are provided for improved control of valve activation/deactivation mechanisms. One example method comprises, adjusting an electromechanical actuator to actuate cylinder valve deactivation/activation mechanisms. The actuator is operated at multiple levels based on engine operating conditions.

Abstract: A camshaft assembly, comprising a camshaft (2) having a receiving space (6) in an interior thereof, at least some sections of the assembly being made of a magnetizable material, and an electromagnetic actuating unit (4) for actuating an actuating partner (5), comprising a control valve of a camshaft adjuster (3), a coil winding (8) and an armature (7) for cooperating with the actuating partner (5), the armature being adjustable by energizing the coil winding (8).

Abstract: A variable valve operating apparatus including an electric motor including a motor housing with a permanent magnet, and a speed reducing mechanism having a casing, the motor housing and the casing of the speed reducing mechanism being coupled to each other by a plurality of bolts, wherein the motor housing includes a convex portion formed in a portion of the motor housing which is opposed to one axial end of the permanent magnet, the convex portion having a threaded hole into which a tip end portion of each bolt is screwed, and a projection formed on an axial end surface of the convex portion in alignment with the threaded hole in an axial direction of the threaded hole, and wherein the axial end surface of the convex portion is located further spaced from the one axial end of the permanent magnet than the projection.

Abstract: An apparatus for actuating at least one outlet valve of a valve-controlled internal combustion engine for motor vehicles, includes an actuating element which is driven by a camshaft. A first piston/cylinder unit, preferably a hydraulically loaded piston/cylinder unit, is provided between a cam of the camshaft and at least one outlet valve. The piston/cylinder unit allows at least one outlet valve to be held in a non-closed intermediate position during an engine braking mode with exhaust-gas backpressure. A second piston/cylinder unit is provided which is configured as a valve-play compensation element, preferably as a hydraulic valve-play compensation element (HVC). At least one valve train-side device is provided between the cam and the at least one outlet valve, which valve train-side device exerts a force which is directed counter to the adjusting action of the HVC but is lower than the latter.

Abstract: A control system for a homogeneous charge compression ignition (HCCI) engine includes first and second modules. The first module determines an adjusted intake valve opening (IVO) timing based on a base IVO timing and an IVO timing adjustment, wherein the IVO timing adjustment is based on one or more of a plurality of operating parameters. The second module controls intake valves of the HCCI engine based on the adjusted IVO timing.

Abstract: The present disclosure provides a variable valve time control system and method. The variable valve time control system comprises an actuator, an actuation switch valve, an electronic control unit and a displacement sensor. The electronic control unit controls the actuation switch valve. The displacement sensor detects the engine valve displacement signal. The electronic control unit calculates the engine valve opening and closing times based on the displacement signal from the engine valve displacement sensor, and translates the engine valve opening and closing times into the corresponding switch times of the actuation-switch-valve power output.

Abstract: A vehicle system includes a position sensor, a current supply module, and a mode indicator module. The position sensor includes: an electromagnet (EM) that generates a magnetic field proximate to one of an intake valve and an exhaust valve of an engine; and a Hall-effect sensor that generates a position signal indicating a position of the one of the intake valve and the exhaust valve based on the magnetic field. The current supply module supplies current to the EM. The mode indicator module indicates whether the one of the intake valve and the exhaust valve is being actuated in a low lift mode or a high lift mode based on the position signal.

Abstract: Provided is a control apparatus for an internal combustion engine which can successfully determine whether or not a failure concerning a stopping operation of an exhaust valve has occurred, without the need of providing a dedicated sensor for the failure determination. An intake variable valve operating apparatus (62) and an exhaust variable valve operating apparatus (64) are included that have valve stop mechanisms capable of switching each operational state of an intake valve (58) and an exhaust valve (60) between a valve operating state and a valve closed/stopped state.

Abstract: In a valve timing control system of an internal combustion engine employing both an electric-motor-driven intake valve timing control device (VTC) and an electric-motor-driven exhaust VTC having similar fundamental configurations, a maximum drive-efficiency motor-speed range of a first electric motor of the intake VTC and a maximum drive-efficiency motor-speed range of a second electric motor of the exhaust VTC are set to differ from each other depending on two different working ranges respectively suitable for the intake VTC and the exhaust VTC such that the maximum drive-efficiency motor-speed range of the intake VTC is set higher than that of the exhaust VTC. A reduction ratio of a first speed reducer configured to reduce a rotational speed of the first electric motor is set higher than that of a second speed reducer configured to reduce a rotational speed of the second electric motor.

Abstract: In a phase adjustment device for a valve drive mechanism of an internal combustion engine, in particular a camshaft adjustment device, with a phase adjustment unit which, for adjusting a phase position in a normal operating mode, comprises a coupling unit for controlling an adjustment gear element by applying a braking force, and with a failsafe adjustment arrangement for setting a defined fail-safe phase position in a fail-safe operating mode, the adjustment unit includes mechanical means for varying the braking force of the coupling unit of the phase adjustment unit for setting the phase angle to a controllable failsafe phase angle position.

Abstract: An electro-hydraulic valve train is configured to change valve lift and valve opening/closing timing according to operation state of an engine. The electro-hydraulic valve train includes a valve stem having a valve head formed at a lower end thereof and a big-diameter stem formed at a middle portion thereof, the big-diameter stem having a larger diameter than the other portion, a swing arm having a roller contacting with a cam of a camshaft and an end connected to the valve stem, the one end being adapted to pivot with respect to the other end according to a rotation of the cam so as to move the valve stem upwardly or downwardly, a first brake unit enclosing the valve stem and adapted to perform brake operation in a case that the valve stem moves upwardly, and a second brake unit mounted at the other end of the swing arm and adapted to selectively move the other end of the swing arm upwardly or downwardly and to perform brake operation in a case that the other end of the swing arm moves downwardly.

Abstract: A valve timing control system for an internal combustion engine, comprises: an electric intake valve timing control apparatus to vary an intake valve timing with torque produced by an electric motor with electric power supplied through a power supply mechanism; and an electric exhaust valve timing control apparatus to vary an exhaust valve timing with torque produced by an electric motor with electric power supplied through a power supply mechanism. A heat generating portion in the power supply mechanism of the intake valve timing control apparatus is made of a heat resisting material whereas a heat generating portion in the power supply mechanism of the exhaust valve timing control apparatus is made of a material lower in heat resistance than the heat resisting material of the intake valve timing control apparatus.

Abstract: In a valve timing control system of an internal combustion engine employing both an electric-motor-driven intake valve timing control device for changing intake valve timing and an electric-motor-driven exhaust valve timing control device for changing exhaust valve timing, the intake valve timing control device includes a less-friction roller speed reducer having a toothed gear and configured to transmit torque by repeated relocations of each of rollers rolling and relocating from one of two adjacent teeth of the toothed gear to the other. In contrast, the exhaust valve timing control device includes a planetary-gear speed reducer having a friction greater than a friction of the roller speed reducer and configured to transmit torque by meshed-engagement of toothed gears in mesh with each other.

Abstract: A method includes energizing a solenoid valve of a hydraulic control system according to a predetermined timing schedule to move a valve member of the solenoid valve. The solenoid valve is operatively connected to the switching component by a fluid control passage, such as a passage in an engine block, to deliver pressurized fluid from a supply passage when the valve member moves to switch the switching component from a first mode to a second mode. An operating parameter of the control system is measured. The operating parameter may be a period of time over which the valve member moves, or a sensed operating parameter of the fluid, such as pressure or temperature. The measured parameter is then compared with a predetermined parameter. Energizing of the solenoid valve is then adjusted based on the difference.

Abstract: The invention relates to a cam actuator (2) for actuating at least one valve (3) slidably mounted in a mounting (1), the device comprising a tappet (8) which is to be mounted on a free end of a stem (3a) of the valve and which is mobile relative to the mounting (1); and a resilient return means (9) for the tappet, which to urge the tappet (8) against the cam (2), characterised in that the device comprises an electromagnetic locking means including an electromagnetic actuator (22) having a coil (24), preferably outside the tappet (8), and at least one pin (12) subjected to the magnetic field of the actuator (22), such that supplying power to the coil (24) causes the selective movement of the pin (12) between a locked position, in which the tappet (8) is translatably linked to the valve (3), and an unlocked position, in which the tappet (8) freely slides on the stem (3a) of the valve.

Abstract: A camless engine operating system that includes an inlet valve switch configured to detect rotational movement of an inlet valve power disc and to output an inlet actuator voltage. A voltage level of the inlet actuator voltage is synchronous with the rotational movement of the inlet valve power disc. An inlet valve is movable to open and close an intake port of a combustion chamber. An inlet valve mechanical force moves the inlet valve to open the intake port. An inlet actuator is configured to exert the inlet valve mechanical force onto the inlet valve. The inlet actuator voltage received by the inlet actuator controls the inlet actuator to exert the inlet valve mechanical force onto the inlet valve.