Automatic draining back flow prevention device
AssigneeWCM Industries, Inc.
InventorsWilliam T. Ball, Eric Pilarczyk
Life of this patent
Estimating the term…
Abstract
A double check valve is provided that includes an in-line inlet check valve and an outlet check valve that cooperate to prevent back flow of fluid through the valve. The check valve also includes at least one vent that allows for fluid trapped within the check valve to drain, thereby preventing freezing of the check valve and hydrant to which it is interconnected. The check valve provided omits many superfluous components and thus is smaller and easier to install than check valves of the prior art.
Claims21
1-16. (canceled)
A back flow prevention device comprising:
- a valve body comprising an inlet and an outlet, wherein one or more vents are defined in the valve body between the inlet and the outlet;
- a seal proximate the one or more vents;
- a plunger proximate the outlet;
- and
- a valve assembly disposed at least partially within the valve body and moveable relative to the seal, wherein:
- in a first condition, when a fluid flow is supplied at the inlet and the plunger extends at least partially out of the outlet, the fluid flow forces the seal to block the one or more vents and moves the valve assembly so that the fluid flow is channeled through the valve body and out the outlet;
- and
- in a second condition, when the fluid flow is removed from the inlet and the plunger extends at least partially out of the outlet, the valve assembly is biased towards a free flow position so that fluid can drain through the valve body and out the outlet.
A system comprising:
- a faucet coupled to a valve, wherein the faucet selectively controls a fluid flow from a fluid source;
- and
- a back flow prevention device comprising:
- a valve cap that removably couples the back flow prevention device to the faucet;
- a valve body comprising an inlet and an outlet, wherein one or more vents are defined in the valve body between the inlet and the outlet, and wherein the inlet couples to the valve cap;
- a hose plunger proximate the outlet;
- and
- a valve assembly disposed at least partially within the valve body,
- wherein when the fluid flow is supplied at the inlet and the hose plunger extends at least partially out of the outlet, the valve assembly blocks the one or more vents and opens the valve assembly so that the fluid flow is channeled through the valve body and out the outlet, and
- wherein when the fluid flow is removed from the inlet and the hose plunger extends at least partially out of the outlet, the valve assembly opens both the one or more vents and the outlet for drainage.
A method of testing a double check valve that includes an inlet check valve and an outlet check valve, the method comprising:
- coupling a hose to a valve body, wherein the valve body includes an inlet and an outlet, wherein one or more vents are defined in the valve body between the inlet and the outlet, and wherein the hose couples to the outlet;
- substantially simultaneously with coupling the hose to the valve body, moving a plunger into the valve body, wherein the plunger forces the outlet check valve towards engagement with a seat within the valve body;
- adding fluid into the outlet of the valve body;
- determining integrity of the engagement between the outlet check valve and the seat, wherein fluid filling the inlet check valve and exiting from the one or more vents indicates that the engagement between the outlet check valve and the seat is broken.
Dependencies are inferred from the claim text.