Combustion condition detection apparatus for an internal combustion engine

摘要

A combustion condition detecting apparatus for an internal combustion engine has a current distributor that distributes an ion current, a band pass filter which extracts a knock vibration component from a current distributor output, a knock determination section which outputs a knock pulse if the extracted knock vibration component is larger than a knock detection threshold value, a combustion determination section which outputs a combustion pulse when an current distributor output is larger than a combustion pulse threshold value, an ignition signal determination section which makes a determination on the basis of an ignition signal as to whether energization of an ignition coil for ignition in another cylinder is started, and an ion current limiting section which limits its ion current output to the current distributor during a predetermined time period after the start of energization of the ignition coil for ignition in the another cylinder.