Patent ID: 7475672

Claim:
Apparatus for producing an ignition spark in an internal combustion engine, said apparatus comprising: an inductive ignition device having a primary coil and a secondary coil, flow of current through said primary coil being controlled by an electronic switching element responsive to a triggering signal; a rotatable body having detectable features on a periphery thereof; a sensor device located adjacent to said rotatable body at a fixed position, said sensor device being operative to produce an output in response to said detectable features; and a controller operative to receive an output from said sensor device and responsively produce said triggering signal, said triggering signal having a variable dwell time and ignition position, said controller being further operative to: ascertain average engine speed and mechanical position by sensing said detectable features; determine said dwell time and said ignition position based thereon; and wherein said controller chronologically locates said ignition position by predicting engine position between two of said detectable features.