Top dead point detector for engine

Abstract

Abstract PURPOSE: To precisely detect the top dead point of an engine by taking into consideration of pressure propagation delay from a pressure generating source in a cylinder to the pressure receiving surface of a pressure gage to accurately specify the abscissa axis and accordingly the cranking angle in a pressure diagram. CONSTITUTION: An arithmetic unit 13 reads a pressure signal from a sample- holding circuit 8 at every cranking angle pulse on the basis of a pulse signal from a multiplier 11 to select three pressure signals varying in crest shape at its level. A quadratic curve is obtained on the basis of these signals with the pulse train of the pulse signals as an independent variable and the pressure level as dependent variable to thereby specify the myltiplying pulse corresponding to the maximum pressure level on the curve. This specified pulses are counted by a counter 12 to thus allow the unit 13 to immediately notify the delayed cranking angle from the top dead point corresponding thereto. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Toshiaki Motoi
• 👤 Shinobu Ishiyama
• 👤 Akio Takamura

Bibliographic Details