| 摘要 |
An internal combustion engine ignition apparatus includes a secondary spark plug having a center electrode to which a high voltage is applied. A cylindrical peripheral electrode surrounds the center electrode and has peripheral openings. Upon the formation of a corona discharge due to the high voltage applied to the center electrode, a strong ionic wind and convection of an air-fuel mixture are produced. The ionic wind causes fuel constituents to be gathered in the vicinity of the peripheral electrode thus preventing production of hydrocarbons due to cooling or quenching of the fuel on the combustion chamber wall. Initial ignition of the air-fuel mixture is by means of a main spark plug. The resultant flames are propagated to the corona discharge portion of the secondary spark plug. The corona discharge is then changed to secondary continuous spark discharge, to thereby positively fire the stratified air-fuel mixture. In another embodiment of the invention the auxiliary combustion chamber has a generally spherical configuration. The spherical auxiliary combustion chamber wall directs the extremely lean air-fuel mixture along a relatively long arcuate path back to outer side areas of the entrance to the auxiliary combustion chamber. The flow out of the auxiliary combustion chamber of the extremely lean air-fuel mixture from which fuel particles have been electrostatically precipitated, is further promoted by forming secondary openings in the wall of the auxiliary combustion chamber. The flow of the very lean air-fuel mixture to either the main or secondary openings in the wall of the auxiliary combustion chamber may be still further promoted by forming arcuate grooves on the inside of the auxiliary combustion chamber wall. The establishment of a corona discharge in either a main or auxiliary combustion chamber is promoted by forming a central electrode with a plurality of projections which extend toward a peripheral electrode which circumscribes the central electrode. |
