Patent attributes
An engine system is provided, which includes a main combustion chamber, a subchamber, an injector that injects fuel into the main combustion chamber, a main spark plug that ignites a mixture gas inside the main combustion chamber, a subspark plug that ignites the mixture gas inside the subchamber, an exhaust gas recirculation (EGR) device and a control device. In a specific range where EGR is performed, the ignition devices are controlled so that a subignition timing is retarded from a main ignition timing, and an ignition phase difference that is a retard amount of the subignition timing from the main ignition timing becomes larger under a high EGR condition than a low EGR condition, the EGR conditions being conditions in the specific range where engine speeds are the same and EGR rates are different, and the high EGR condition being larger in the EGR rate than the low EGR condition.
