Patent ID: 7325565
Filing Date: 2008-02-05
Classification: E03F,F16K,Y10T

Abstract:
1. A backflow valve for detecting a backflow condition comprising: a fluid pump; a valve housing having a valve inlet, a valve outlet, and a valve cavity in communication with both the valve inlet and the valve outlet; an inlet conduit for introducing liquid to the valve inlet; an outlet conduit for receiving the liquid from the valve outlet after the liquid passes through the valve cavity; a switch within the valve cavity, the switch being movable from an off position to an on position in response to liquid filling the valve cavity from a normal liquid level to a backflow liquid level above the normal liquid level; a manifold having an air opening therein; a fluid conduit connecting the fluid pump to the manifold for introducing fluid to the manifold and then outwardly through the air opening; a bladder located outside the manifold, the air opening, and the fluid conduit, the bladder being movable in response to introduction of fluid pressure from the air opening of the manifold to move from a deflated condition to an inflated condition; a first valve member below the bladder and movable from an open position permitting liquid to be introduced from the inlet conduit to the valve cavity and the outlet conduit to a closed position shutting off introduction of fluid from the inlet conduit to the valve cavity and the outlet conduit in response to movement of the bladder from the deflated condition to the inflated condition; the fluid pump being electrically connected to the switch and being actuated when the switch is in the on position to cause fluid to be introduced under pressure through the fluid conduit to the manifold and thence through the air opening to inflate the bladder from the deflated condition to the inflated condition.