Check valve for drainage conduits

摘要

The back-flow prevention valve has a floating ball (4) which lies in a side passage of the drainage pipe (2) under normal conditions and which moves into sealing engagement with a valve seat adjacent the bottom of the drainage pipe for preventing a back-flow. The side passage is provided by a pipe section (3b) which is open at both ends, extending at an angle between the drainage pipe and the drainage line (1), for bypassing the end section (3a) of the drainage pipe.