Patent ID: 8220483

Claim:
A non-return valve device for shutting off a flow of a medium through a pipeline and hoses, comprising a housing for installing in the pipeline and a valve, wherein: the housing comprises a flow channel having a flowed-through cross section that can be closed by the valve; the valve comprises a valve disc for closing the cross section and a valve stem for guiding the valve, and the valve is mounted by means of the valve stem in a retaining plate, so as to be displaceable in a direction of the flow of the medium through the pipeline; the retaining plate and/or the valve comprises means for avoiding residues of the medium transported in the pipeline; a central bore in the retaining plate, the central bore having a circumference, the central bore comprising substantially a cross-sectional shape corresponding to the cross section of the valve stem, and the central bore comprising a plurality of protrusions extending from the circumference that run in the direction of the flow of the medium to avoid residues in the central bore, the plurality of protrusions being distributed over the circumference of the central bore; at least one recess on the front of the retaining plate; and the valve stem is displaceably mounted in the central bore, and the at least one recess on the front of the retaining plate points counter to the direction of the flow of the medium to prevent residues in such a way that the medium is discharged via the at least one recess on the front of the retaining plate towards the central bore.