Patent ID: 6799557
Filing Date: 2004-10-05
Classification: F02D,F02P,Y02T

Abstract:
An ignition apparatus for use with an internal combustion engine to produce an electrical spark at a spark ignition device, said apparatus comprising:a magnet assembly operatively revolved along a circular path, said magnet assembly including a pair of pole faces; a magnetically permeable core mounted adjacent to said circular path and having at least two leg portions each including a respective end face, said leg portions being situated such that said pole faces pass proximate to said end faces during revolution of said magnet assembly and produce a time-varying magnetic flux in said magnetically permeable core; a transformer having a primary coil and a secondary coil related by a predetermined step-up ratio, said secondary coil electrically connected during operation to the spark ignition device; a spark generation circuit operative to apply a primary voltage pulse to said primary coil responsive to a triggering signal, said primary voltage pulse producing a spark generating pulse in said secondary coil; and triggering circuitry including a processor operative to receive a signal indicative of the rotational position of said magnet and generate a triggering signal, said triggering circuitry being operative to switch between a first mode wherein said triggering signal occurs at a fixed angle relative to top dead center and a second mode wherein said triggering signal occurs at a variable angle relative to top dead center.