Patent Document ID: 20010006004
Application ID: 09733958
Patent Flag: 0

Claim One:
1. Method for exactly determining the top dead centre (TDC) of an internal combustion engine ( 1 ) from the pressure curve inside the cylinder (D), characterized by detecting at various operating points on an engine ( 1 ) selected according to its specification the pressure curve inside the cylinder (D), and after direct measurement of the TDC time in degrees of crank angle (°CA), associated time values likewise in crank angle degrees (°CA) detected at the same time as digitized value pairs, correlated and stored in a data set. Furthermore the pressure inside the cylinder (D) is if necessary put into a knowledge-based system (NN 10 ) together with engine-specific parameters as input variables, its output giving a certain value for the TDC time which then trains the system (NN 10 ) with elements from the data set till it recognizes from the pressure inside the cylinder (D) the associated TDC time of the direct measurement at all operating points used for training purposes, also if necessary for different engine-specific parameters, with the required accuracy, and finally determining from the measured pressure in the cylinder (D) at operating points not trained, with different engine-specific parameters if necessary, the TDC time with the help of an unaltered but trained, knowledge-based system (NN 10 ).