Method for operating an otto-cycle internal combustion engine with fuel injection on a cold start
AssigneeRobert Bosch GmbH
InventorsKlaus Joos, Ralf Daeubel, Gerd Grass, Ruediger Weiss, Hansjoerg Bochum, Edmund Schaut
Life of this patent
Estimating the term…
Abstract
A method is provided for operating a spark ignition internal combustion engine having fuel injection at a cold start. The method retards the spark angle to a cold start value at least for the first combustion in at least one cylinder of the internal combustion engine during a cold start phase, the fuel injected into the cylinder being brought to combustion, and the method sets the spark angle to normal, to end the cold start phase.
Claims8
A method of operating a spark ignition internal combustion engine having fuel injection at a cold start, characterized by the following procedural steps:
- retardation (13) of the spark angle to a cold start value at least for the first combustion in at least one cylinder of the internal combustion engine during a cold start phase, the fuel injected into the cylinder being brought to combustion;
- setting of the spark angle to normal (14) to end the cold start phase.
The method according to one of the preceding claims, wherein the spark angle is set to normal (14) in a single step to set a desired operating performance value.
The method according to one of the preceding claims, wherein the spark angle is set to normal (14) in a plurality of transitional steps to set a desired operating performance value.
The method according to one of the preceding claims, wherein the cold start value is set for each cylinder individually.
The method according to one of the preceding claims, wherein the cold start value is set during the cold start phase in each case for the next combustion of a respective cylinder.
The method according to one of the preceding claims, wherein the cold start value is set using a retardation (13) adjusted to the operating temperature of the respective cylinder.
The method according to one of the preceding claims, wherein the retardation (13) takes place on condition that the number of ignitions (z) is smaller than or equal to the value of a parameter (n) which by definition is greater than or equal to one and smaller than or equal to the number of cylinders in the internal combustion engine, and at the same time the combustion chamber temperature (To) before the first ignition is lower than a threshold temperature (Ts).
Dependencies are inferred from the claim text.