PURPOSE: To shorten the time required for matching by superimposing the fine pseudo irregular signal on the ignition timing, determining the torque sensitivity with the correlation method, and skipping a fixed number of subsequent ignition timing set values when its change is small.
CONSTITUTION: The load and rotating speed of an engine 21 are kept constant by a constant-operating condition holding means 22, and the ignition signal is received from a generating means 24 in response to the ignition timing set by a setting means 23. The periodic fine pseudo irregular signal from a generating means 26 is superimposed on the ignition timing set signal by a means 27, the mutual correlation function between the pseudo irregular signal and the engine torque detected by a torque sensor 28 is determined by a calculating means 29, the impulse response is determined by a calculating means 30, the torque sensitivity is determined by a calculating means 31, if a judging means 33 judges that the difference from the previous torque sensitivity stored in a memory means 32 is within the preset value, a means 34 skips a fixed number of subsequent ignition timing set values from the setting means. The measuring and calculating time can be shortened.
IKEURA KENJI
SAITO MASAAKI
KURIHARA NOBUO
HITACHI LTD
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