An internal combustion engine for a motor vehicle includes a combustion chamber with a gas exchange valve which is movable between an open position and a first closed position. The gas exchange valve is movable on its path from the open position in a direction of the first closed position into an intermediate position located between the open position and the first closed position and is holdable in the intermediate position at least during a part of a compression cycle of the combustion chamber following the open position of the gas exchange valve and is movable into a second closed position following the intermediate position. The part comprises more than a half of the compression cycle and less than a whole of the compression cycle. The gas exchange valve is an inlet valve via which the combustion chamber is supplyable at least with air.

The disclosure relates to a method for controlling an internal combustion engine. The internal combustion engine includes a cylinder and a piston, which runs in the cylinder, together delimiting a working chamber. The working chamber is supplied with fresh air from a intake section via an inlet valve and is connected to an exhaust manifold via exhaust valves. The internal combustion engine includes a variable valve actuation system for the actuation of the inlet valves, controlling the opening time and/or the closing time and/or the lift. A strategy for shutting down the internal combustion engine includes controlling the inlet valves of individual or all working chambers in such a way that the transfer of fresh air from the intake section to the exhaust manifold is reduced or avoided and that the drag torque of the internal combustion engine is reduced.

An engine system comprising an internal combustion engine and a turbocharger, where a diameter of the at least one intake valve is greater than a diameter of the at least one exhaust valve, the salient angle of the piston bowl is at least 10 degrees, the ratio between the piston bowl opening diameter and the piston bowl depth is approximately 0.5 to 2.0, the intake valve opens before top dead center on an exhaust stroke of the internal combustion engine and closes before bottom dead center of an intake stroke of the internal combustion engine, and the turbocharger has a combined efficiency of more than 50%.

Methods, devices, controllers, and algorithms are described for operating an internal combustion engine wherein at least some firing opportunities utilize low temperature gasoline combustion (LTGC). Other firing opportunities may be skipped or utilize some other type of combustion, such as spark ignition. The nature of any particular firing opportunity is dynamically determined during engine operation, often on a firing opportunity by firing opportunity basis. Firings that utilize LTGC produce little, if any, nitrous oxides in the exhaust stream and thus, in some implementations, may require no aftertreatment system to remove them from the exhaust stream.

The disclosure relates to a method for controlling an internal combustion engine configured with a belt starter generator or an electric machine of a hybrid powertrain. The internal combustion engine includes a cylinder and a piston, which together delimit a working chamber. The internal combustion engine includes a variable valve actuation system for actuation of inlet valves of the working chambers, controlling the opening time and/or the closing time and/or the lift. A strategy for operating the internal combustion engine with a negative drive torque or when shutting down or when starting up the internal combustion includes controlling the inlet valves of individual or all working chambers in such a way that the transfer of fresh air from an intake section to an exhaust manifold is controlled and that the drag torque of the internal combustion is reduced.

A control device is for an internal combustion engine including a throttle valve and a variable valve mechanism, and configured to be operated at a prescribed target air-fuel ratio and capable of restarting from an intermittent stop. The control device includes an electronic control unit configured to start the internal combustion engine after starting an intake air amount reduction control, when a fuel injection amount equal to or larger than a prescribed amount is required and an intermittent stop time is equal to or longer than a prescribed time in a case of the restart from the intermittent stop. The intermittent stop time is a stop time from an immediately preceding intermittent stop to a current restart of the internal combustion engine. The intake air amount reduction control is a control of reducing the intake air amount by operating the variable valve mechanism with the throttle valve kept fully closed.

A method of operating a rocker arm assembly in a cylinder deactivation mode according to one example of the present disclosure includes providing a two-step variable valve lift rocker arm assembly and a deactivating lash adjuster. Operation of the rocker arm assembly in cylinder deactivation mode is selected. The rocker arm assembly is operated in low-lift mode based on the selection of the cylinder deactivation mode. Subsequent to or concurrently with operating the rocker arm assembly in the low-lit mode, the deactivating lash adjuster is operated in the unlatched mode. A first amount of the total lost motion required for cylinder deactivation mode is accounted for by lost motion of the rocker arm assembly operating in the low-lift mode and a remainder amount of the total lost motion is accounted for by lost motion of the deactivating lash adjuster operating in the unlatched mode.

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.

A miller cycle engine according to the present disclosure includes: a variable valve operating device configured to continuously change the closing timing of an intake valve; a throttle valve arranged in an intake air passage; and a control device configured to execute an early closing miller cycle operation mode to control the variable valve operating device such that the intake valve closes at an intake bottom dead center or earlier. The control device is configured to: execute a late closing mode (e.g., decompression mode) to retard the closing timing relative to the intake bottom dead center at the time of engine start-up; and execute, where the pressure in the intake air passage has decreased to a first threshold value or lower first after the engine start-up, a mode switching processing to switch from the late closing mode to the early closing miller cycle operation mode.

Systems and related methods include a rocker arm having integrated components, including a lost motion actuator piston and components for resetting the lost motion actuator piston to provide normal valve closing or late valve closing. Selective reset is facilitated by a reset piston and a blocking piston disposed in a hydraulic circuit including a reset passage. In a non-resetting mode of operation, the blocking piston may block oil flow within the reset passage, regardless of the position of the reset piston, which facilitates late valve closing. An alternative embodiment includes a blocking sleeve disposed concentrically relative to the reset piston.