Patent ID: 7469576
Filing Date: 2008-12-30
Classification: F02D,G01M

Abstract:
1. A method for determining Top Dead Center rotational location of a piston in a cylinder of a multiple-cylinder internal combustion engine having a pressure sensor in the cylinder and having a crankshaft rotational position sensor, comprising the steps of: a) determining the rotational Location of Peak Pressure in said cylinder with respect to the indicated rotational location of said crankshaft position sensor by a procedure selected from the group consisting of determining Continuity of Polytropic Coefficient and determining Waveform Symmetry extrapolated to a peak, wherein said determining of Location of Peak Pressure by determining Continuity of Polytropic Coefficient includes the algorithm and wherein said determining of Location of Peak Pressure by determining Waveform Symmetry extrapolated to a peak includes the extrapolation algorithm and b) adding a calculated Heat Loss Offset to said determined Location of Peak Pressure to provide said Top Dead Center rotational location of said piston in said cylinder.