KNOCKING DETECTION CIRCUIT FOR INTERNAL COMBUSTION ENGINE

摘要

PURPOSE:To enable accurate identification of cylinders generating knocking and a knocking level by detecting spark signals of an ignition plug mounted to the cylinder for measuring knocking from those of the ignition plugs. CONSTITUTION:A knock sensor 1 converts the vibration of an engine into a voltage waveform as shown by A. A comparator 2 inputs the output of the knock sensor 1 through a filter 2 and outputs a knocking pulse as shown by B when it exceeds the set reference voltage. A monostable multivibrator 5 detects a spark signal of an ignition plug P4 from a cylinder for measuring knocking from spark signals of ignition plugs P1-P4 as shown by C and output spark discharge pulses as shown by D. An AND circuit 6 inputs the output of the monostable multivibrator 5 and a comparator 3 and generates an output pulse as shown by E. The output pulse is produced when a knocking occurs in a measuring cylinder. It is amplified to a level perceivable to a person as shown by F with a monostable multivibrator 7 to flash a lamp 9.