Control system of internal combustion engine

A control device of an internal combustion engine comprising:

• a main combustion chamber;
• an auxiliary chamber formed at a central portion of a top surface of the main combustion chamber and communicating with the inside of the main combustion chamber through communicating holes, said auxiliary chamber including a spark plug and an auxiliary fuel injector that injects a liquid fuel, an air-fuel mixture in the main combustion chamber being burned by jet flames ejected from the communicating holes when making an air-fuel mixture in the auxiliary chamber burn by the spark plug;
• a tumble flow control valve to control a flow path of a flow of intake air in an intake port so as to cause the generation of a tumble flow swirling around an axis perpendicular to a cylinder axis in the main combustion chamber;
• and
• an electronic control unit configured to control the spark plug, the auxiliary fuel injector, and the tumble flow control valve, wherein
• said auxiliary chamber being provided with a plurality of the communicating holes radially extending from a peripheral part of an end portion of the auxiliary chamber, which end portion is located on the main combustion chamber side, toward a peripheral part of the main combustion chamber and opening inside a flow path of the tumble flow,
• injection ports of the auxiliary fuel injector are oriented toward a tumble flow inflow peripheral region which is located on said peripheral part of the end portion of the auxiliary chamber at a place located on a side where the tumble flow flows in from the communicating holes, and
• the electronic control unit controls the auxiliary fuel injector to inject auxiliary fuel toward the tumble flow inflow peripheral region of the auxiliary chamber when the tumble flow is controlled to be generated in the main combustion chamber by the tumble flow control valve and controls the auxiliary fuel injector to stop injecting the auxiliary fuel when the generation of the tumble flow is stopped by the tumble flow control valve.