Patent ID: 6449946
Filing Date: 2002-09-17
Classification: F02B,F02D,Y02T

Abstract:
A control apparatus for a direct-injection engine, which comprises a fuel injection valve to directily inject fuel into a combustion chamber, and an exhaust gas puryfying catalyst inserted in an exhaust path, and divisionally injects fuel in at least two injections including a trailing injection that begins to inject after a middle period of a compression stroke, and a leading injection earlier than the trailing injection within a period from an intake stroke to an ignition timing before the catalyst warms up, comprising:varying means for forcibly changing an intake flow strength given by (intake flow angular velocity/engine rotation angular velocity) in the combustion chamber, and wherein an air-feul ratio in the combustion chamber is set to be &lgr;&ap;1 before the catalyst warms up, and said varying means operates to divisionally inject fuel at least during a former period from engine start until the catalyst is in a partial activation state, which is an intermediate point during the catalyst temperature rise, an HC purifying ratio of the catalyst increasing according to the catalyst temperature rise but the HC purifying ratio being smaller than a maximum HC purifying ratio of the catalyst before the catalyst warms up, and to set the intake flow strength in the former period to be lower than in a latter period after the former period starting from the intermediate point.