Additional control valve in the intake pipe of an internal combustion engine

The auxiliary control valve has a section (32) of the air intake channel widened out in the flow direction for providing a valve seat (50), with an annular flow cross-section (40) defined between the widened section and a flow body (36) arranged coaxially within it. The flow body incorporates a valve element (46) coaxial to the flow direction, providing part of the surface of the flow body in the open position and sealed against the valve seat in the closed position.