F01L2001/0537

Valve actuation system for an internal combustion engine

A valve actuation system for an internal combustion engine The valve actuation system (S) for an internal combustion engine comprises: ⋅a rocker (6) pivotably mounted around a pivot axis (A6), comprising: ⋅a driven end portion (62) for cooperating with a rotating cam including a main bump and at least one smaller auxiliary bump; ⋅an actuating end portion (63) including a piston (8) for opening at least one valve of the engine following the cooperation of the driven end portion (62) with a bump of the cam, the piston (8) being slidably mounted relative to the rocker (6) between a extended position allowing said piston (8) to open said valve when the driven end portion (62) contacts the auxiliary bump, and a retracted position preventing said piston (8) to open said valve when the driven end portion (62) contacts the auxiliary bump; ⋅a fluid circuit for causing the piston (8) to move from its retracted position to its extended position; ⋅a reset circuit comprising a reset valve (99) rotatably mounted relative to the rocker (6), between an inactive position, and an active position in which the reset valve (99) causes the fluid to be drained out of the fluid circuit to allow the piston (8) to move towards its retracted position; ⋅a lever (7) pivotably mounted around a pivot axis (A6), the lever (7) having a driven end portion (72) adapted to cooperate with a rotating reset cam including a bump, and an actuating end portion (73) for rotating the reset valve (99) from its inactive position towards its active position following the cooperation of the lever driven end portion (72) with the bump of the reset cam; ⋅rotational coupling means (75, 95) between the lever (7) and the reset valve (99), said rotational coupling means having a transmission ratio greater than 1.

Control device for internal combustion engine

A control device for an internal combustion engine includes an internal combustion engine and a valve opening-closing timing control device. The valve opening-closing timing control device has a phase adjustment mechanism for setting a relative rotation phase of a driving-side rotator and a driven-side rotator. The phase adjustment mechanism overlaps a timing of opening an intake valve with a timing of opening an exhaust valve, by setting, in a predetermined period, the relative rotation phase such that the exhaust valve closes after a top dead center position has been reached, and a bypass passage is provided that connects an exhaust passage of one cylinder that is in an exhaust process to the exhaust passage of another cylinder that is in an intake process at the same time as the exhaust process.

Valve arrangement and valve guide

A valve arrangement is provided for supplying air to a combustion chamber of an internal combustion engine, the valve arrangement including a first valve, the first valve including a first valve head, a first valve stem and an internal cavity, which is partly located in the first valve stem and open towards a lower surface of the first valve head, a valve guide arranged to surround a portion of the first valve stem such that the first valve stem is movable in the valve guide along a longitudinal direction between an upper, closed position of the valve, and a lower, open position, in which open position air may be supplied to the combustion chamber past the first valve head, the valve guide including an air passage allowing supply of additional air to the combustion chamber via the internal cavity in the first valve, when the first valve is in its closed position. The valve arrangement includes a guide leakage preventing means for preventing liquid from leaking from a region externally of the first valve stem to the valve guide air passage.

Monitoring deviations occurring in the valve drive of an internal combustion engine, and electronic engine control units for executing such methods

Various embodiments include a method for detecting deviations occurring in the valve drive of an internal combustion engine comprising: measuring dynamic pressure oscillations of intake air in an air intake tract of respective internal combustion engine during operation; calculating an inlet valve stroke phase difference and/or an outlet valve stroke phase difference based on the measured dynamic pressure oscillation; calculating a valve stroke phase deviation value with respect to a valve stroke phase reference value based on the calculated phase difference; and calculating a first valve drive deviation value based on the valve stroke phase deviation value.

VALVE TIMING CONTROLLER

A valve timing controller includes: a driving-side rotation member rotatable around a rotation axis and rotating in synchronization with a crankshaft of an internal combustion engine; a driven-side rotation member rotatable around the rotation axis and rotating integrally with a camshaft of the engine; a phase regulating mechanism setting a relative rotation phase of the driving-side and driven-side rotation members by an electric motor; a detection unit detecting the relative rotation phase; a stop control portion displacing the relative rotation phase by controlling the electric motor to stop the engine after the relative rotation phase reaches a stop phase; and a correction control portion displacing the relative rotation phase in a direction closer to the stop phase by controlling the electric motor, when the relative rotation phase is displaced beyond a set amount from the stop phase, in a state where the engine is stopped by the stop control portion.

CAM PHASER FOR DOUBLE CAMSHAFT
20210310382 · 2021-10-07 ·

A cam phaser for a double camshaft, the cam phaser comprising: a rotor; and a stator, wherein the rotor is a rotatable relative to the stator about a rotor axis of the rotor that is coaxial to a longitudinal axis of the stator, wherein a radial vane of the rotor is positionable between two bars of the stator, wherein the radial vane divides an intermediary space formed between the two bars into two pressure cavities, wherein the double camshaft includes a first camshaft that is configured as a hollow cylinder and a second camshaft that is at least partially received in the first camshaft wherein the first camshaft and the second camshaft are rotatable relative to each other, wherein one of the first camshaft and the second camshaft is connected torque proof with the rotor and another of the first camshaft and the second camshaft is connected torque proof with the stator, wherein the rotor is movable by pressures in the two pressure chambers to cause a rotation of the first camshaft and the second camshaft relative to each other, wherein a hydraulic valve is arranged concentric to the first camshaft, the second camshaft and the rotor, and wherein the hydraulic valve is arranged axially between the second camshaft and the rotor.

Cylinder head arrangement for variable valve actuation rocker arm assemblies

A novel cylinder head arrangement for an in-line four cylinder or eight cylinder engine. A modified arrangement allows additional space for installation of wider rocker arm assemblies used for variable valve lift (VVL), cylinder deactivation (CDA) and other types of variable valve actuation (VVA). In one embodiment, cam towers adjacent the end two cylinders are not used. At least one end support is used, which may be an outboard bearing on a camshaft for each end. The wider rocker assemblies may then be installed. In another embodiment, cam towers adjacent the inner two cylinders are eliminated and a single camshaft support piece with a support bearing is installed between the inner cylinders to provide support for the camshafts. The wider rocker assemblies may then be installed on at least one of the middle cylinders. A novel oil control valve operates latches in switching rocker arm assemblies.

Method for operating an internal combustion engine, and internal combustion engine

The invention relates to a method for operating an internal combustion engine, which has an internal combustion motor, which forms at least two combustion chambers, which are bounded by cylinders formed in a cylinder housing and by pistons guided up and down cyclically in said cylinders and in which thermodynamic cycles can be performed during operation of the internal combustion engine, wherein then a gas exchange in the combustion chambers is controlled by means of at least one intake valve (28) and one exhaust valve in the case of each combustion chamber, which valves are actuated by means of cams, and wherein a first operating state is provided, in which the thermodynamic cycles are performed both in a first combustion chamber and in a second combustion chamber and a second operating state is provided, in which the thermodynamic cycles are performed in the first combustion chamber and the thermodynamic cycles are not performed in the second combustion chamber, is characterized in that, in order to switch from the first operating state to the second operating state, a switch is made from the use of a first intake cam to the use of a second intake cam for the actuation of the intake valve associated with the first combustion chamber. Such a method makes it possible to realize a switchover from full operation to partial operation in manner that is as torque-neutral as possible in that the torque component that ceases because of the deactivation of the cylinder or cylinders provided therefor is compensated by the one or more cylinders that continue to actively operate, at least also in that, in the event of the switchover, the delivery ratio, i.e. the ratio of the mass of fresh gas actually contained in the cylinder after the conclusion of a charge cycle to the theoretical maximum possible mass, is increased for said cylinders and, in particular, is set as high as possible.

Control device for engine

A control device for an engine 1 including cylinders, and configured to perform a reduced-cylinder operation by idling some of cylinders. The control device includes a hydraulic valve-stopping mechanism 14b which closes the intake and exhaust valves 41, 51 of the cylinders in response to establishment of the reduced-cylinder operation execution condition, a hydraulic variable valve timing mechanism 19 capable of changing a phase of the exhaust valve 51 of the engine 1, and an ECU 110 which controls the valve-stopping mechanism 14b and the hydraulic variable valve timing mechanism 19. In response to establishment of the reduced-cylinder operation execution condition, the ECU 110 allows the hydraulic variable valve timing mechanism 19 to execute the phase change to the exhaust valve 51, and subsequently allows the valve-stopping mechanism 14b to bring the intake and exhaust valves 41, 51 of the cylinders into closed state.

Mounting structure of oil control valve unit and motorcycle
11105228 · 2021-08-31 · ·

There is provided a mounting structure of an oil control valve unit configured to control a hydraulic pressure to a variable valve timing device of an engine. The engine is supported by a vehicle body frame. A heat exchanger is mounted in front of the engine. The oil control valve unit is mounted at a side of the engine. A part of the vehicle body frame is arranged between the oil control valve unit and the heat exchanger in a front and rear direction.