Patent ID: 7198025
Filing Date: 2007-04-03
Classification: F02B,F02D,Y02T

Abstract:
1. An in-cylinder injection type spark-ignition internal combustion engine comprising: a fuel injection valve for injecting fuel directly into a combustion chamber; a spark plug with an electrode part located near a path of fuel spray injected by the fuel injection valve; a piston arranged to be able to turn back the fuel spray which has passed by the electrode part of the spark plug so that the fuel spray is transferred again to near the electrode part; a mode change determination means for determining whether to carry out a change between stratified combustion in a first spray transfer mode in which ignition is made at the time when the fuel spray injected by the fuel injection valve passes by the electrode part of the spark plug, and stratified combustion in a second spray transfer mode in which ignition is made at the time when the fuel spray which has passed by the electrode part is transferred again to near the electrode part by the piston turning the fuel spray back, in a coexistence operational region where stratified combustion in the first spray transfer mode and stratified combustion in the second spray transfer mode are both practicable; an injection timing and ignition timing calculation means for, when the mode change determination means determines to change the spray transfer mode, calculating a set of a fuel injection timing and an ignition timing capable of achieving almost the same engine torque as a torque produced by the internal combustion engine before the change, by stratified combustion in the spray transfer mode after the change; and a spray transfer mode change means for, when the mode change determination means determines to change the spray transfer mode, stepwise changing the fuel injection timing and ignition timing for the Internal combustion engine, on the basis of the result of calculation by the injection timing and ignition timing calculation means.