Humidifier Inlet Valve Layout to Prevent Pressure Support Back-Flow
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional humidifiers in pressure support systems fail to effectively prevent back-flow of fluid into the pressure support device, particularly due to condensation and tilting, which can damage the device and lead to bacterial growth.
Innovation Solution
A humidifier design with a valve mechanism that moves between open and closed positions based on the orientation of the system, preventing fluid back-flow by blocking the inlet when the system is tilted or if pressure drops below a threshold, ensuring that fluid does not enter the pressure support device.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a patient circuit is provided between the humidification chamber and pressure support device to prevent fluid back-flow, then device protection is improved, but gas flow resistance increases and system complexity increases
Solution Approach 1:
The patent extracts the back-flow prevention function from the patient circuit and relocates it to the humidification chamber inlet. By positioning the inlet upstream of the fluid in the chamber, the system prevents fluid back-flow without requiring an additional patient circuit, thus reducing system complexity while maintaining device protection
Solution Approach 2:
The patent introduces an intermediary structure (the upstream inlet position) that acts as a barrier to fluid back-flow. This intermediary positioning creates a physical separation that prevents fluid from reaching the pressure support device outlet, protecting the device without adding complex components
2Stability of the object's composition
If the humidification chamber is rigidly coupled to the pressure support device, then system stability is improved, but fluid back-flow risk increases due to direct connection
Solution Approach 1:
The patent applies local quality by creating a specific spatial relationship at the inlet of the humidification chamber. The inlet is positioned upstream of the fluid level, creating a local protective zone that prevents fluid back-flow while allowing the rest of the system to maintain rigid coupling for stability
3Reliability
If a snorkel-like inlet is used to minimize backsplash, then protection against tilting is improved, but protection against condensation and rainout is insufficient
Solution Approach 1:
The patent segments the inlet protection function from the overall inlet structure. By positioning the inlet upstream of the fluid in the chamber, it creates a separate protective mechanism that addresses condensation and rainout independently from tilting protection, providing comprehensive protection against multiple harmful factors
4Reliability
If the valve blocks the inlet to prevent back-flow, then fluid protection is improved, but gas flow interruption occurs
Solution Approach 1:
The patent employs a dynamic valve mechanism that automatically adjusts its state based on system orientation and pressure conditions. The valve opens during normal operation to allow gas flow and closes when back-flow is detected, providing adaptive protection that maintains productivity while ensuring fluid protection
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 valve mechanism effectively prevents fluid back-flow into the pressure support device, reducing the risk of damage and bacterial growth, while allowing uninterrupted gas flow to the patient during normal operation.
Implementation Method 1
a valve (902) positioned in the inlet (914) and upstream of the fluid chamber (912), the valve (902) movable between an open position in which the inlet (914) is substantially unblocked and a closed position in which the inlet (914) is substantially blocked
Implementation Method 2
The gas interacts with the water in the humidifier chamber and exits into tubing where it is communicated to an airway of a patient
Data Source
AI summary
A humidifier for use with a pressure support system. The humidifier includes a body having an inlet, a fluid holding chamber, and an outlet. The inlet is positioned upstream and in fluid communication with the fluid holding chamber. The outlet is positioned downstream of and in fluid communication with the fluid holding chamber. A back-flow preventing valve is positioned upstream of the fluid chamber. The back-flow preventing valve is movable between an open position, in which the inlet is unblocked, and a closed position in which the inlet is blocked. In the closed position, the back-flow preventing valve prevents fluid, fluid vapor, or both from entering the pressure support via the inlet to the humidifier.