Patent ID: 6904891

Claim:
An internal combustion engine, comprising: a main section defining an intake port leading to a cylinder of the engine; an intake valve arranged to open and closet a downstream port end of the intake port; and a flow regulating section to regulate an intake air flow in the intake port into the cylinder, the flow regulating section including; a partition extending in the intake port in a longitudinal direction of the intake port from an upstream end to a downstream end, and dividing the intake port into first and second passage sections; a gas motion control valve located by the upstream end of the partition, to open and close the second passage section; a connection passage formed near the gas control valve, to connect the first and second passage sections, and to allow recirculation flow of intake air in the second passage section from the second passage section to the first passage section when the second passage section is closed by the gas motion control valve; and a bulge formed in a first part of a circumferential region surrounding the downstream port end of the intake port on a side near the second passage section.