Abstract: An internal combustion engine includes an electro-hydraulic system for variable actuation of intake valves where each cylinder has two intake valves, associated with two intake conduits. A first conduit is generates within the cylinder a tumble motion of airflow introduced therein, when the intake valve associated thereto is at least partially opened. The second intake conduit generates within the cylinder a swirl motion of airflow introduced therein when the second intake valve is at least partially opened. A controller of controls one or more control valves to open only one of the intake valves of each cylinder in a condition of reduced engine operation, below a predetermined load and/or a predetermined speed of the engine, and to always open both intake valves in the remaining conditions of engine operation. The first intake valve is the only valve to be opened in the reduced engine operation condition.

Abstract: An engine includes at least one cylinder, a first intake valve and a second intake valve associated with the cylinder, to control a flow of intake air from a first intake duct and a second intake duct, respectively. The two intake ducts communicate with a common intake manifold, so as to receive air at the same pressure. During the intake stage, in each cylinder operating cycle, initially an opening and closing movement of only the first intake valve is activated, while the second intake valve remains closed and, subsequently, an opening and closing movement of only said second intake valve is activated, while the first intake valve remains closed. In this way, the two air flows at the same pressure entering the cylinder give rise to a high turbulent kinetic energy, to the advantage of combustion efficiency and reduction of harmful exhaust emissions.

Abstract: In an internal combustion engine provided with an electro-hydraulic system for variable actuation of the intake valves of the engine, each cylinder has two intake valves, which are associated with two intake conduits and are controlled by a single cam of a camshaft through a single hydraulic circuit. The communication of the hydraulic actuators of the two intake valves with a discharge channel is controlled by two electrically-actuated control valves, both of an on/off two-position type, arranged in series with each other along a hydraulic line for communication between the a pressure volume and the discharge channel.

Abstract: An engine includes at least one cylinder, a first intake valve and a second intake valve associated with the cylinder, to control a flow of intake air from a first intake duct and a second intake duct, respectively. The two intake ducts communicate with a common intake manifold, so as to receive air at the same pressure. During the intake stage, in each cylinder operating cycle, initially an opening and closing movement of only the first intake valve is activated, while the second intake valve remains closed and, subsequently, an opening and closing movement of only said second intake valve is activated, while the first intake valve remains closed. In this way, the two air flows at the same pressure entering the cylinder give rise to a high turbulent kinetic energy, to the advantage of combustion efficiency and reduction of harmful exhaust emissions.

Abstract: An internal combustion engine includes an electro-hydraulic system for variable actuation of intake valves where each cylinder has two intake valves, associated with two intake conduits. A first conduit is generates within the cylinder a tumble motion of airflow introduced therein, when the intake valve associated thereto is at least partially opened. The second intake conduit generates within the cylinder a swirl motion of airflow introduced therein when the second intake valve is at least partially opened. A controller of controls one or more control valves to open only one of the intake valves of each cylinder in a condition of reduced engine operation, below a predetermined load and/or a predetermined speed of the engine, and to always open both intake valves in the remaining conditions of engine operation. The first intake valve is the only valve to be opened in the reduced engine operation condition.

Abstract: In an internal combustion engine provided with an electro-hydraulic system for variable actuation of the intake valves of the engine, each cylinder has two intake valves, which are associated with two intake conduits and are controlled by a single cam of a camshaft through a single hydraulic circuit. The communication of the hydraulic actuators of the two intake valves with a discharge channel is controlled by two electrically-actuated control valves, both of an on/off two-position type, arranged in series with each other along a hydraulic line for communication between the a pressure volume and the discharge channel.

Abstract: An atomizer of a fuel electro-injector is equipped with a nozzle and a valve needle having a head, which is coupled to a sealing seat of the nozzle, and stem, which engages an inner seat of the nozzle; the stem and the nozzle define an annular passageway with a chamber that axially terminates at the sealing seat; the stem has an intermediate portion coupled in an axially sliding manner in the inner seat and defining a plurality of channels, the outlets of which are arranged on the annular chamber; the sealing seat and the head of the valve needle define a discharge section, which is annular and has a width that increases as the opening stroke of the valve needle proceeds; the ratio between the depth and the outer chord of the minimum cross-section of the channels is greater than or equal to two.

Abstract: An actuating system of an engine valve comprises a movable member, for example, in the form of a master piston controlled by a cam of a camshaft. A slave piston is hydraulically controlled by the master piston by means of a volume of pressurized fluid, to open said engine valve against the action of a return spring. The system also comprises an auxiliary device for applying an additional force to the engine valve to keep the engine valve in a closed position. The auxiliary device is configured or controlled in such a way that the total force tending to keep the engine valve in its closed position varies during each rotation cycle of the cam. The total force is higher at least in one part of the rotation cycle of the cam wherein the engine valve must remain in its closed position, and is, instead, reduced at least in one part of the rotation cycle of the cam wherein the engine valve is not in its closed position.

Abstract: An actuating system of an engine valve comprises a movable member, for example, in the form of a master piston controlled by a cam of a camshaft. A slave piston is hydraulically controlled by the master piston by means of a volume of pressurized fluid, to open said engine valve against the action of a return spring. The system also comprises an auxiliary device for applying an additional force to the engine valve to keep the engine valve in a closed position. The auxiliary device is configured or controlled in such a way that the total force tending to keep the engine valve in its closed position varies during each rotation cycle of the cam. The total force is higher at least in one part of the rotation cycle of the cam wherein the engine valve must remain in its closed position, and is, instead, reduced at least in one part of the rotation cycle of the cam wherein the engine valve is not in its closed position.

Abstract: A system for variable actuation of an engine valve of an internal-combustion engine includes a master piston and a slave piston, driven by the master piston. A control valve controls a communication of a volume of a pressurized fluid with a lower pressure environment, which is connected to a fluid accumulator, and an electronic control unit controls the electrically operated control valve. A device for dampening pressure oscillations is connected to the volume of pressurized fluid and includes an additional volume adapted for receiving fluid from the volume of pressurized fluid only when, following upon oscillations of the pressure in the volume of pressurized fluid, the pressure exceeds a maximum threshold value, which is higher than a mean pressure value that is set up in the volume of pressurized fluid when the master piston drives the slave piston in normal operating conditions.

Abstract: A system for variable actuation of an engine valve of an engine includes a master piston driven by a cam of a camshaft. A slave piston is driven by the master piston by a volume of pressurized fluid. The slave piston causes the engine valve to open, against the action of a spring. A control valve controls a communication between pressurized fluid and an environment at lower pressure, with which a fluid accumulator is in communication. A control unit is programmed for controlling the control valve according to one or more different valve modes. When one of these valve modes is actuated, the control valve opens the communication in advance with respect to the end of the lift cycle of the cam, and not after closing of the engine valve to prevent or reduce a decrease in pressure in the volume of pressurized fluid after closing of the engine valve.

Abstract: A fuel electro-injector for a fuel injection system for an internal combustion engine, having an atomizer equipped with a nozzle and a valve needle defining a discharge section that is annular and has a width that continuously increases as the opening stroke of the valve needle proceeds. The opening stroke is directed outwards and is caused, in a proportional manner, by the operation of an electric actuator. The electro-injector has a high-pressure environment with an annular passageway around the lateral outer surface of the valve needle to supply fuel to the discharge section, and a low-pressure environment, which communicates with a fuel outlet and is separated from the high-pressure environment by a dynamic seal between the valve needle and the nozzle.

Abstract: An atomizer of a fuel electro-injector is equipped with a nozzle and a valve needle having a head, which is coupled to a sealing seat of the nozzle, and stem, which engages an inner seat of the nozzle; the stem and the nozzle define an annular passageway with a chamber that axially terminates at the sealing seat; the stem has an intermediate portion coupled in an axially sliding manner in the inner seat and defining a plurality of channels, the outlets of which are arranged on the annular chamber; the sealing seat and the head of the valve needle define a discharge section, which is annular and has a width that increases as the opening stroke of the valve needle proceeds; the ratio between the depth and the outer chord of the minimum cross-section of the channels is greater than or equal to two.

Abstract: An electrically actuated control valve has three mouths and three operating positions, in which the three mouths includes a first mouth for inlet of a working fluid, and a second mouth and a third mouth for outlet of the working fluid. The three operating positions include a first operating position in which a passage of fluid from the first mouth to the second mouth and the third mouth is enabled, a second operating position in which a passage of fluid from the first mouth to only one of said second and third mouths is enabled, and a third operating position in which the passage of fluid from the first to the second mouth and the third mouth is disabled. The control valve includes an electric or electromagnetic actuator for controlling the passage of fluid from the first mouth to the second and third mouths providing the aforesaid three operating positions.

Abstract: A system for variable actuation of an engine valve of an engine includes a master piston driven by a cam of a camshaft. A slave piston is driven by the master piston by a volume of pressurized fluid. The slave piston causes the engine valve to open, against the action of a spring. A control valve controls a communication between pressurized fluid and an environment at lower pressure, with which a fluid accumulator is in communication. A control unit is programmed for controlling the control valve according to one or more different valve modes. When one of these valve modes is actuated, the control valve opens the communication in advance with respect to the end of the lift cycle of the cam, and not after closing of the engine valve to prevent or reduce a decrease in pressure in the volume of pressurized fluid after closing of the engine valve.

Abstract: A system for variable actuation of an engine valve of an internal-combustion engine includes a master piston and a slave piston, driven by the master piston. A control valve controls a communication of a volume of a pressurized fluid with a lower pressure environment, which is connected to a fluid accumulator, and an electronic control unit controls the electrically operated control valve. A device for dampening pressure oscillations is connected to the volume of pressurized fluid and includes an additional volume adapted for receiving fluid from the volume of pressurized fluid only when, following upon oscillations of the pressure in the volume of pressurized fluid, the pressure exceeds a maximum threshold value, which is higher than a mean pressure value that is set up in the volume of pressurized fluid when the master piston drives the slave piston in normal operating conditions.

Abstract: An electrically actuated valve includes a first working way and a second working way and a poppet configured for providing a seal on a valve seat set hydraulically between the first working way and the second working way. The poppet includes a first operating position, a second operating position, and a third operating position, and is displaceable by an electrical-actuation device In the first operating position, a passage area for a hydraulic fluid defined between said valve seat and said poppet has a maximum value In the second operating position, the passage area is partialized and has a value lower than said maximum value In the third operating position, the poppet is in contact with the valve seat, and the passage area has a substantially zero value, so that the first working way is isolated from the second working way.

Abstract: A fuel injector has an injector body and a control rod, which is movable in the injector body along an axis to control the opening/closing of a nozzle that injects fuel into a cylinder of the engine; the injector body houses a metering servovalve having a control chamber, which is axially delimited by the control rod and communicates with an inlet and with a discharge channel; the metering servovalve is provided with a shutter, which slides axially on an axial guide, from which the discharge channel exits, to open and close the discharge channel and, in consequence, vary the pressure in the control chamber; the discharge channel has three restrictions having calibrated passage sections and arranged in series with each other to divide the pressure drop along the discharge channel.

Abstract: An internal-combustion engine includes a three-way, three-position solenoid valve, having an inlet communicating with a pressurized-fluid chamber and with a hydraulic actuator of an intake valve, and two outlets communicating with an actuator of another intake valve of a cylinder and the exhaust channel. The solenoid valve has a first position, in which the inlet communicates with both outlets, a second position, in which the inlet communicates only with the outlet connected to the actuator of the intake valve and a third position, in which the inlet does not communicate with any of the two outlets. During at least part of an active stroke of a tappet, the solenoid valve is kept in the third position to render the first intake valve active. During the active stroke of the tappet, the solenoid valve is never brought into the second position so that the second intake valve always remains closed.

Abstract: An internal-combustion engine includes a system for variable actuation of intake valves, including a control valve for each cylinder, which controls communication of a pressurized-fluid chamber with a discharge channel. The control valve has at least three different positions, namely, a first completely open position, a second partially open position, and a third completely closed position. Electronic control means are programmed for keeping the control valve in its closed position in operating stages in which the intake valve must remain coupled to the respective cam and for bringing the control valve from its completely closed position to its partially open position or to its completely open position in operating stages in which the intake valve must be uncoupled from the respective cam, selection between the first position and said second position of the control valve being made as a function of one or more operating parameters of the engine.