Patent ID: 7143784

Claim:
Sanitary fitting ( 1 ) constructed as a check valve comprising a housing ( 2 ), including multiple walls, which ( 2 ) can be inserted in a sanitary water pipe having at least two mutually adjacent housing walls ( 6 , 7 ) which enclose an inner region ( 8 ) therebetween, one of the housing walls ( 7 ) of the housing ( 2 ) is formed of a flexible and/or elastic material and is tubular in form, the elastic housing wall ( 7 ) can be brought or moved to a spacing from the adjacent housing wall ( 6 ), for pressure equalization with the check valve ( 1 ) in a closed state and a fluid volume shut off downstream with compression of the at least one inner region ( 8 ) against the adjacent housing wall ( 6 ) or with expansion of the at least one inner region ( 8 ), whereby an outer one of the housing walls ( 7 ) is formed of the flexible and/or elastic material, and the elastic housing wall ( 7 ) is movable by a fluid volume acting on the elastic housing wall ( 7 ) from outside and compressing the inner region, or by a fluid volume flowing into the inner region through at least one passage channel or at least one passage opening ( 20 ), with expansion of the inner region ( 8 ).