Abstract: A non-return valve device for an internal combustion engine includes a valve housing comprising an aperture with a downstream end arranged in a duct housing. The aperture defines a flow cross section. A valve seat surrounds the flow cross section. A valve closing member, provided as leaf springs, adapts, closes or opens the flow cross section. A distance between each of the leaf springs in their maximum opened position at the downstream end of the aperture and the duct housing arranged opposite to each of the leaf springs has a maximum which is twice as large as a distance between each of the leaf springs in their maximum opened position and the valve seat arranged opposite to each of the leaf springs. Defining inner walls of the duct housing downstream of the valve housing are arranged so that the flow cross section is first continuously reduced and then continuously enlarged.

Abstract: A non-return valve device for an internal combustion engine includes a valve housing comprising an aperture with a downstream end arranged in a duct housing. The aperture defines a flow cross section. A valve seat surrounds the flow cross section. A valve closing member, provided as leaf springs, adapts, closes or opens the flow cross section. A distance between each of the leaf springs in their maximum opened position at the downstream end of the aperture and the duct housing arranged opposite to each of the leaf springs has a maximum which is twice as large as a distance between each of the leaf springs in their maximum opened position and the valve seat arranged opposite to each of the leaf springs.