Abstract: In an internal combustion engine with variable actuation valves, each variable actuation valve is actuated by an actuator assembly including an actuating piston slidably mounted in a guide bushing. Between the actuating piston and the stem of the respective valve is interposed an auxiliary hydraulic tappet positioned outside the guide bushing of the actuating piston, so that said bushing can be dimensioned with a relatively small diameter, regardless of the outer diameter of the auxiliary hydraulic tappet. The intake valves of a same cylinder are actuated by a single cam, by means of a single pumping piston and by means of a single pressure chamber controlled by a single solenoid valve.

Abstract: In an internal combustion engine with variable actuation valves, each variable actuation valve is actuated by an actuator assembly including an actuating piston slidably mounted in a guide bushing. Between the actuating piston and the stem of the respective valve is interposed an auxiliary hydraulic tappet positioned outside the guide bushing of the actuating piston, so that said bushing can be dimensioned with a relatively small diameter, regardless of the outer diameter of the auxiliary hydraulic tappet. The intake valves of a same cylinder are actuated by a single cam, by means of a single pumping piston and by means of a single pressure chamber controlled by a single solenoid valve.

Abstract: A multiple cylinder engine is described, provided with an electronically controlled hydraulic system for actuating the intake valves, in which intake valves and exhaust valves are controlled by a single camshaft.

Abstract: A multiple cylinder engine is described, provided with an electronically controlled hydraulic system for actuating the intake valves, in which intake valves and exhaust valves are controlled by a single camshaft.

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: 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 said 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.