Double Check Valve Venting for Backflow and Freeze Prevention
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing back flow preventors for exterior fluid delivery systems are either unreliable, prone to contamination, or excessively complex and costly, failing to effectively prevent back flow and freeze damage without manual operation or additional valves.
Innovation Solution
A double check valve system with a valve body containing an inlet and outlet check valve, biased by springs, that self-drains and prevents back flow without a third check valve, reducing size, weight, and complexity while meeting ASSE regulations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single check valve with manual draining feature is used, then back flow prevention is provided, but the device requires manual operation and is unreliable for freeze prevention
Solution Approach 1:
The check valve incorporates an automatic self-draining mechanism that activates when a hose is disconnected. The valve body includes a drain passage and check valve assembly that automatically opens to drain water from the sill cock without requiring manual intervention, thereby preventing freeze damage reliably
Solution Approach 2:
The valve is designed to perform drainage action in advance before freezing conditions occur. When hose disconnection is detected, the check valve automatically opens the drain passage to remove water from the system proactively, preventing subsequent freeze damage
2Reliability
If multiple check valves are used to prevent back flow, then back flow prevention is improved, but device complexity and cost increase
Solution Approach 1:
The invention integrates multiple functions into a single check valve assembly. The valve body combines the back flow prevention check valve mechanism with an automatic self-draining feature, eliminating the need for separate draining valves or complex multi-valve systems while maintaining effective back flow prevention
Solution Approach 2:
The check valve assembly performs multiple functions simultaneously: it prevents back flow into the water supply and automatically drains water from the sill cock when needed. This multi-functional design reduces the overall number of components required in the system
3Reliability
If foreign material is present in the valve, then contamination risk increases, but back flow prevention may be compromised
Solution Approach 1:
The valve body incorporates a screen or filter element that extracts and removes foreign material from the water flow before it can enter the check valve mechanism. This prevents contamination while maintaining the reliability of the back flow prevention function
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The double check valve system effectively prevents back flow and freeze damage, is simpler and lighter, and meets regulatory standards, offering automatic self-draining and reduced risk of contamination, while being easier to manufacture and maintain.
Implementation Method 1
A double check valve system with a valve body containing an inlet and outlet check valve, biased by springs
Data Source
AI summary
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.