초록 ▼

A backflow preventor with increased performance, and increased ease of installation is provided. The check valves are configured to assist in redirecting flow along the desired pathway, when they are in the open position. The pathway is designed so that the number of changes of flow direction of the

A backflow preventor with increased performance, and increased ease of installation is provided. The check valves are configured to assist in redirecting flow along the desired pathway, when they are in the open position. The pathway is designed so that the number of changes of flow direction of the average streamline flow is reduced, preferably being about 180°. The check valves are configured to reduce or eliminate divergent flow around the edges of the valve disks. A check valve with a reduced hold-open pressure includes a biasing device, such as a spring, directly connected to a pivoting clapper at one end and to the valve body at the other end. No intervening pivoting links are used between the spring and the clapper. Preferably, the clapper is connected only by being pivoted to the valve body and by the spring connecting it to the valve body.

대표청구항 ▼

A backflow preventor apparatus for connection to parallel, oppositely-flowing inlet and outlet conduits, comprising: a housing configured to accommodate first and second valves, and to receive fluid flow from said inlet conduit flowing in a first direction; a first valve mounted in said housing havi

A backflow preventor apparatus for connection to parallel, oppositely-flowing inlet and outlet conduits, comprising: a housing configured to accommodate first and second valves, and to receive fluid flow from said inlet conduit flowing in a first direction; a first valve mounted in said housing having a first clapper movable between an open configuration permitting flow through said first valve and a closed configuration preventing flow; a second valve mounted in said housing having a clapper movable between an open configuration permitting flow through said second valve and a closed configuration preventing flow; said first valve clapper, when in said open configuration, being positioned to direct said flow from said first direction to provide flow in a second direction, different from said first direction, towards said second valve; said second valve clapper, when in said open configuration, being positioned to direct said flow from said second direction to a third direction, different from said second direction towards said outlet conduit.