Method for starting a multi-cylinder internal combustion engine

A method for stating a multi-cylinder internal combustion engine (1) in the forward direction, comprising the following steps:

• ascertaining the position of a piston (2) in a cylinder (3) of the engine (1);
• injecting fuel into a combustion chamber (4) of the particular cylinder (3) whose piston (2) is in a working phase;
• moving the engine (1) first in a reverse direction, by the injection of fuel into a combustion chamber (4) of at least one cylinder (3) whose piston (2) is in a compression phase as viewed in a forward direction;
• igniting the fuel compressed in the combustion chamber (4) of the at least one cylinder (3), wherein the rotary motion in the reverse direction comes to a stop before the bottom dead center (UT) of the piston (2) of the at least one cylinder (3) is reached;
• placing inlet and/or outlet valves (5) of the at least one cylinder (3) whose piston (2) is located before a too dead center (OT), as viewed in the forward direction, into a position corresponding to a compression phase;
• and
• starting the engine (1) in the forward direction,
• wherein the inlet and/or outlet valves (5) of two cylinders (3), whose pistons (2) are located before a top dead center (OT) as viewed in the forward direction are brought into a position corresponding to the compression phase before the starting process.

A method for stating a multi-cylinder internal combustion engine (1) in the forward direction, comprising the following steps:

• ascertaining the position of a piston (2) in a cylinder (3) of the engine (1);
• injecting fuel into a combustion chamber (4) of the particular cylinder (3) whose piston (2) is in a working phase;
• moving the engine (1) first in a reverse direction, by the injection of fuel into a combustion chamber (4) of at least one cylinder (3) whose piston (2) is in a compression phase as viewed in a forward direction;
• igniting the fuel compressed in the combustion chamber (4) of the at least one cylinder (3), wherein the rotary motion in the reverse direction comes to a stop before the bottom dead center (UT) of the piston (2) of the at least one cylinder (3) is reached;
• placing inlet and/or outlet valves (5) of the at least one cylinder (3) whos piston (2) is located before a top dead center (OT), as viewed in the forward direction, into a position corresponding to a compression phase;
• and
• starting the engine (1) in the forward direction,
• wherein during the rotary motion of the engine (1) in the reverse direction, the inlet and/or outlet valves (5) of a cylinder (3), whose piston (2) is located—viewed in the forward direction—in an aspiration phase, are actuated in a targeted way such that the rotary motion of the engine (1) in the reverse direction comes to a stop before bottom dead center (UT) of the piston (2) of the at least one cylinder (3) is reached, and
• wherein the inlet and outlet valves (5) of the cylinder (3) whose piston (2) is located—viewed in the forward direction—in an aspiration phase, are closed during the rotary motion of the engine (1) in the reverse direction.

A method for stating a multi-cylinder internal combustion engine (1) in the forward direction, comprising the following steps:

• ascertaining the position of a piston (2) in a cylinder (3) of the engine (1);
• injecting fuel into a combustion chamber (4) of the particular cylinder (3) whose piston (2) is in a working phase;
• moving the engine (1) first in a reverse direction, by the injection of fuel into a combustion chamber (4) of at least one cylinder (3) whose piston (2) is in a compression phase as viewed in a forward direction;
• igniting the fuel compressed in the combustion chamber (4) of the at least one cylinder (3), wherein the rotary motion in the reverse direction comes to a stop before the bottom dead center (UT) of the piston (2) of the at least one cylinder (3) is reached;
• placing inlet and/or outlet valves (5) of the at least one cylinder (3) whose piston (2) is located before a top dead center (OT), as viewed in the forward direction, into a position corresponding to a compression phase;
• and
• starting the engine (1) in the forward direction,
• wherein during the rotary motion of the engine (1) in the reverse direction, the inlet and/or outlet valves (5) of a cylinder (3), whose piston (2) is located—viewed in the forward direction—in an aspiration phase, are actuated in a targeted way such that the rotary motion of the engine (1) in the reverse direction comes to a stop before bottom dead center (UT) of the piston (2) of the at least one cylinder (3) is reached,
• wherein the inlet and outlet valves (5) of the cylinder (3) whose piston (2) is located—viewed in the forward direction—in an aspiration phase, are closed during the rotary motion of the engine (1) in the reverse direction, and
• wherein the inlet and outlet valves (5) of the cylinder (3) whose piston (2) is located—viewed in the forward direction—in an aspiration phase, are kept closed for a predeterminable period of time after the reversal of the direction of rotation of the engine (1).

A method for stating a multi-cylinder internal combustion engine (1) in the forward direction, comprising the following steps:

• ascertaining the position of a piston (2) in a cylinder (3) of the engine (1);
• injecting fuel into a combustion chamber (4) of the particular cylinder (3) whose piston (2) is in a working phase;
• moving the engine (1) first in a reverse direction, by the injection of fuel into a combustion chamber (4) of at least one cylinder (3) whose piston (2) is in a compression phase as viewed in a forward direction;
• igniting the fuel compressed in the combustion chamber (4) of the at least one cylinder (3), wherein the rotary motion in the reverse direction comes to a stop before the bottom dead center (UT) of the piston (2) of the at least one cylinder (3) is reached;
• placing inlet and/or outlet valves (5) of the at least one cylinder (3) whose piston (2) is located before a top dead center (OT), as viewed in the forward direction, into a position corresponding to a compression phase;
• and
• starting the engine (1) in the forward direction,
• wherein after an unsuccessful first ignition of the fuel injected into the at least one cylinder (3), the method is performed again, with inverted phases of the individual cylinders (3).

A method for stating a multi-cylinder internal combustion engine (1) in the forward direction, comprising the following steps:

• ascertaining the position of a piston (2) in a cylinder (3) of the engine (1);
• injecting fuel into a combustion chamber (4) of the particular cylinder (3) whose piston (2) is in a working phase;
• moving the engine (i) first in a reverse direction, by the injection of fuel into a combustion chamber (4) of at least one cylinder (3) whose piston (2) is in a compression phase as viewed in a forward direction;
• igniting the fuel compressed in the combustion chamber (4) of the at least one cylinder (3), wherein the rotary motion in the reverse direction comes to a stop before the bottom dead center (UT) of the piston (2) of the at least one cylinder (3) is reached;
• placing inlet and/or outlet valves (6) of the at least one cylinder (3) whose piston (2) is located before a top dead center (OT), as viewed in the forward direction, into a position corresponding to a compression phase;
• and
• starting the engine (1) in the forward direction,
• wherein during the starting process in a compression phase of a cylinder (3) of the engine (1), the corresponding inlet valve (5) of the cylinder (3) is closed late.

A control element formed as a read-only memory or flash memory for a control unit (12) of an internal combustion engine (1) in which a program is stored that can be run on a computing device, in particular a microprocessor, and is suitable for performing a method including the following steps:

• ascertaining the position of a piston (2) in a cylinder (3) of the engine (1);
• injecting fuel into a combustion chamber (4) of the particular cylinder (3) whose piston (2) is in a working phase;
• moving the engine (1) first in a reverse direction, by the injection of fuel into a combustion chamber (4) of at least one cylinder (3) whose piston (2) is in a compression phase as viewed in a forward direction;
• igniting the fuel compressed in the combustion chamber (4) of the at least one cylinder (3), wherein the rotary motion in the reverse direction comes to a stop before the bottom dead center (UT) of the piston (2) of the at least one cylinder (3) is reached;
• placing inlet and/or outlet valves (5) of the at least one cylinder (3) whose piston (2) is located before a top dead center (OT), as viewed in the forward direction, into a position corresponding to a compression phase;
• and
• starting the engine (1) in the forward direction.

A control unit (12) of a multi-cylinder internal combustion engine (1), in particular of a motor vehicle, wherein the engine (1) has a detector for ascertaining the position of a piston (2) in a cylinder (3) of the engine (1), a fuel metering system for injecting fuel into a combustion chamber (4) of the particular cylinder (3) whose piston (2) is located in a working phase, and a spark plug (9) for igniting fuel compressed in the combustion chamber (4), characterized in that the control unit (12) triggers the fuel metering system in such a way that is injects fuel into the combustion chamber (4) of at least one cylinder (3), whose piston (2) is located—viewed in the forward direction—in a compression phase;

• that the control unit (12) triggers the spark plug (9) in such a way that the spark plug ignites the fuel compressed in the combustion chamber (4) of the at least one cylinder (3), thereby causing a rotary motion of the engine in the reverse direction, which is ended before the bottom dead center (UT) of the pistons (2) of the at least one cylinder (3) is reached;
• and the control unit (12) has means for starting the engine (1) in such a way that they start it in the forward direction, wherein inlet and/or outlet valves (5) of the at least one cylinder (3) whose piston (2) is located before a top dead center (OT), as viewed in the forward direction, are placed into a position corresponding to a compression phase before the engine is started.