Back water closure for e.g. floor drains, has automatic float buckle with sealing area having independent sealing surfaces such that one sealing surface blocks the flow opening in case the other sealing surface is leaking

摘要

An automatic float buckle (20) has a sealing area (22) to plug a flow opening (4) during a back pressure state. The sealing area having independent sealing surfaces such that one sealing surface blocks the flow opening in case the other sealing surface is leaking.