INTAKE AIR CONTROLLER IN INTERNAL COMBUSTION ENGINE

PURPOSE:To secure performance at the time of high rotation and improve the state of combustion at the time of a partial load by providing an intake air control member for varying one of intake sectional areas of intake ports formed inside a cylinder head, and providing the intake air control member retractably on the intake port wall face. CONSTITUTION:In take valves 4, 5 are arranged in intake ports 2,3 formed inside a cylinder head 1, respectively, and an opening/closing valve 6 serving as an intake air control member rotated by a rotary shaft 7 is provided in one side intake ports 3. The opening/closing valve 6 is rotated at the time of a partial load so as to be in contact with the branching part 9, and the intake sectional area is throttled by closing the most of the intake ports 3, and thereby flow speed of intake air is increased so as to improve the state of combustion and fuel consumption. On the other hand, the opening/closing valve 6 is opened at the time of fully opening the throttle valve, and the opening/closing valve 6' is housed and retracted inside the recess part 3a so as to suck a sufficient quantity of intake air.