PURPOSE: To improve the accuracy of data in the vicinity of a top dead point, which is important in analysis of internal cylinder pressure, by obtaining a top dead point position signal and an internal cylinder pressure signal, and rearranging the data as one degree data for every forward half cycle and every backward half cycle, with the top dead point position signal as a center.
CONSTITUTION: Based on the signal from a top dead point position detector 3, a time interval S corresponding to about 0.2 degree in angle is computed by an operator 6. The top dead point position signal is made to be a triggering signal 3a at the time interval S. An internal cylinder pressure signal is inputted to the operator 6 from a pressure gage 4 through an AD converter 5. The top dead point position signal is inputted to the operator 6 from the detector 3 through the AD converter 5. Data number Mi and Mi+1 between rotation reference signals are counted. Data pitches, by which the data numbers are converted into one degree data, are computed (Li=Mi/360 and Li+1= Mi+1/360). With the top dead point position signal as a center, the data are rearranged at one degree interval in accordance with the pitches Li and Li+1 for every forward half cycle and every backward half cycle. The forward half cycle is computed by an expression I and the backward half cycle is computed by an expression II, where INT means conversion to integers.
TSUNODA AKIRA
OOYA HIDEO
IRIE YASUTAKA
