BACKFLOW PREVENTER

摘要

A backflow preventer for preventing reverse water flow having as a part thereof a transverse wall between inlet and outlet water passages and with a valve disc in the form of an annular member mounted to be resiliently urged against said transverse wall and block a series of circularly disposed flow passages at all times except when normal water flow occurs through the backflow preventer. The valve disc is simply constructed of a resilient material in planar form and is mounted to be dished and urged against said transverse wall for seating engagement therewith.