An electronic control unit of an internal combustion engine is configured to control the fuel injection valve and to control a spark plug if necessary such that fuel is combusted by pre-mixture compression ignition combustion or flame propagation combustion. The electronic control unit is configured to perform homogeneous combustion in a flame ignition operation range when switching failure has not occurred, the homogeneous combustion being combustion in which fuel homogeneously diffused into the combustion chamber is ignited using the spark plug and is combusted by flame propagation combustion. The electronic control unit is configured to perform spray-guided stratified combustion in a second operation range when the switching failure has occurred, the spray-guided stratified combustion being combustion in which fuel in the fuel injection path is ignited using the spark plug and is combusted by the flame propagation combustion.

A reciprocating combustion engine includes at least one cylinder, in which a reciprocating piston is arranged back and forth movable. The reciprocating combustion engine includes a pin structure arranged on the combustion chamber side in the area of the cylinder head or the piston bottom. Due to the pin structure, local peak temperatures can be avoided during the combustion process, so that NOx emissions can be avoided or at least greatly reduced. A motor vehicle, for example a commercial vehicle, includes a reciprocating combustion engine.

A reciprocating combustion engine includes at least one cylinder, in which a reciprocating piston is arranged back and forth movable. The reciprocating combustion engine includes a pin structure arranged on the combustion chamber side in the area of the cylinder head or the piston bottom. Due to the pin structure, local peak temperatures can be avoided during the combustion process, so that NOx emissions can be avoided or at least greatly reduced. A motor vehicle, for example a commercial vehicle, includes a reciprocating combustion engine.

A fuel estimation apparatus includes a combustion characteristic acquisition portion and a mixing ratio estimation portion. The combustion characteristic acquisition portion acquiring a combustion characteristic value indicating a physical amount relating to a combustion of an internal combustion engine acquires the combustion characteristic values of the combustions executed in different combustion conditions. The mixing ratio estimation portion estimates the mixing ratios of various components included in a fuel, based on the combustion characteristic values acquired by the combustion characteristic acquisition portion.

An internal combustion engine includes a piston and a fuel injection valve. The fuel injection valve includes a first injection hole, a second injection hole, a first needle configured to open and close the first injection hole, and a second needle configured to open and close the second injection hole. The first injection hole and the second injection hole are configured such that a portion of a fuel spray injected from the first injection hole and a portion of a fuel spray injected from the second injection hole overlap each other at a position apart at a predetermined distance from a side wall of a cavity of the piston. The second needle is configured to start operation in order to open the second injection hole after a predetermined time has elapsed from a point of time when the first needle starts operation in order to open the first injection hole.

An internal combustion engine includes a piston and a fuel injection valve. The fuel injection valve includes a first injection hole, a second injection hole, a first needle configured to open and close the first injection hole, and a second needle configured to open and close the second injection hole. The first injection hole and the second injection hole are configured such that a portion of a fuel spray injected from the first injection hole and a portion of a fuel spray injected from the second injection hole overlap each other at a position apart at a predetermined distance from a side wall of a cavity of the piston. The second needle is configured to start operation in order to open the second injection hole after a predetermined time has elapsed from a point of time when the first needle starts operation in order to open the first injection hole.

A fuel injection valve has first injection holes, second injection holes, a first needle that opens and closes the first injection holes, and a second needle. The fuel injection valve is arranged such that a part of fuel injected from the first injection hole and a part of fuel injected from the second injection hole are gathered together at a position spaced from the side wall of the cavity by a predetermined distance. The second needle starts operating to open the second injection holes, after a predetermined time elapses from a point in time at which the first needle starts operating to open the first injection holes.

A fuel injection valve has first injection holes, second injection holes, a first needle that opens and closes the first injection holes, and a second needle. The fuel injection valve is arranged such that a part of fuel injected from the first injection hole and a part of fuel injected from the second injection hole are gathered together at a position spaced from the side wall of the cavity by a predetermined distance. The second needle starts operating to open the second injection holes, after a predetermined time elapses from a point in time at which the first needle starts operating to open the first injection holes.

The invention relates to a method for operating an internal combustion engine (1) provided with at least one working cylinder (3a-3d) each with an associated auxiliary cylinder (5a-5d), which engine (1) is operable in spark ignition and compression ignition modes. Each working cylinder (3a-3d) comprises a working piston (7a-7a) connected to a first crankshaft (9), and each auxiliary cylinder (5a-5d) comprises an auxiliary piston (10a-10d) connected to a second crankshaft (12). The first crankshaft (9) is connected to the second crankshaft (12) to drive the second crankshaft (12) at half the rotational speed of the first crankshaft (9). A device for controlling the phase angle is arranged between the first and second crankshafts. The method involves controlling the phase shift device in order to retain residual exhaust gas and increase the compression ratio. A current combustion phasing timing is determined, and the combustion phasing timing is corrected by increasing or decreasing the phase angle to achieve a desired combustion phasing timing.

The invention relates to a method for operating an internal combustion engine (1) provided with at least one working cylinder (3a-3d) each with an associated auxiliary cylinder (5a-5d), which engine (1) is operable in spark ignition and compression ignition modes. Each working cylinder (3a-3d) comprises a working piston (7a-7a) connected to a first crankshaft (9), and each auxiliary cylinder (5a-5d) comprises an auxiliary piston (10a-10d) connected to a second crankshaft (12). The first crankshaft (9) is connected to the second crankshaft (12) to drive the second crankshaft (12) at half the rotational speed of the first crankshaft (9). A device for controlling the phase angle is arranged between the first and second crankshafts. The method involves controlling the phase shift device in order to retain residual exhaust gas and increase the compression ratio. A current combustion phasing timing is determined, and the combustion phasing timing is corrected by increasing or decreasing the phase angle to achieve a desired combustion phasing timing.