초록 ▼

A self-diagnosing ignition drive circuit for applying a first ignition drive signal to a spark plug in an internal combustion engine cylinder for generating an arc across the electrodes thereof to ignite an air/fuel mixture in the cylinder and, following a delay period, applying a second ignition dr

A self-diagnosing ignition drive circuit for applying a first ignition drive signal to a spark plug in an internal combustion engine cylinder for generating an arc across the electrodes thereof to ignite an air/fuel mixture in the cylinder and, following a delay period, applying a second ignition drive signal to the spark plug for generating a second arc across the electrodes to contribute combustion energy and to provide for measurement of the frequency content of energy trapped in an ignition coil during combustion. If the frequency content includes a predetermined frequency, improper ignition in the cylinder is diagnosed through excitation of a natural frequency of a misfire detection circuit coupled to the ignition coil corresponding to at least one engine cylinder.

대표청구항 ▼

A self-diagnosing ignition control apparatus for driving sequential first and second drive signals across spaced electrodes of a spark plug in an engine cylinder to ignite an air/fuel mixture in the engine cylinder and to diagnose improper ignition of the air/fuel mixture, comprising: a double strik

A self-diagnosing ignition control apparatus for driving sequential first and second drive signals across spaced electrodes of a spark plug in an engine cylinder to ignite an air/fuel mixture in the engine cylinder and to diagnose improper ignition of the air/fuel mixture, comprising: a double strike ignition drive circuit having an ignition coil for delivering sequential first and second drive signals to the spark plug producing respective first and second arcs across the spark plug electrodes, the first arc for igniting the air/fuel mixture and the second arc for measuring a frequency band of energy trapped in the ignition coil; a measurement circuit coupled to the ignition coil and having a network with a predetermined natural frequency, the network disposed between a terminal of the ignition coil and a ground reference, wherein the second drive signal includes a frequency component substantially at the predetermined natural frequency when improper ignition occurs and wherein the second drive signal does not include a frequency component at the predetermined natural frequency when proper ignition occurs; and the measurement circuit further comprising diagnostic circuitry for diagnosing the improper ignition by distinguishing excitation of the natural frequency of the network when a frequency component is present in the second drive signal substantially at the predetermined natural frequency.