SYSTEM FOR CONTROLLING IGNITION ENERGY OF AN INTERNAL COMBUSTION ENGINE

摘要

A system for controlling ignition energy of an internal combustion engine includes an ignition coil having a primary coil (102) and a secondary coil (104) coupled to first and second electrodes of an ignition plug (50) defining a spark gap (65) therebetween, wherein the primary coil (102) is operable to induce a spark voltage across the secondary coil (104) and across the spark gap (65). The secondary coil (104) is responsive to the spark voltage to produce a discharge current across the spark gap (65) of the ignition plug (50). In accordance with one aspect of the invention, means (112, 208, 206) are provided for controllably shunting the primary coil (102) to thereby control the duration of discharge current across the spark gap (65) of the ignition plug (50). In accordance with another aspect of the present invention, means (118) are further provided for drawing discharge current away from the ignition plug (50) to thereby limit the magnitude of the discharge current within some time period after the transfer of energy form the primary coil (102) to the secondary coil (104) begins. The principles of the present invention are accordingly applicable to control the duration and/or magnitude of ignition plug discharge current to thereby minimize electrode erosion while maximizing ignitability in either a conventional ignition plug-based ignition system or an arc propelling ignition plug-based ignition system.