Air intake system for multi-cylinder engine, an engine equipped therewith and rotary-type throttle valve therefor

The system has a valve body (8) in a throttle valve device (7) and formed with spaces, which are brought in communication with intake passage. The rotational movement of the valve body achieves a state where intake air is applied through a part of branched intake passages with remaining passages blocking air supply into a combustion chamber, and another state where air is supplied through all branched passages. The valve body is of circular shape when viewed along its rotational axis to rotate about the axis. An independent claim is also included for an engine equipped with an air intake system.