Mask Assembly Flexible Seal Preload Rotation Friction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing mask designs face challenges in creating a reliable seal between the mask frame and swivel connector or elbow, particularly with materials like polypropylene that are difficult to mold to precise dimensions, leading to leakage and friction issues during rotation.
Innovation Solution
The mask assembly incorporates interlocking sealing portions with a flexible element that flexes to create a preload, allowing for a secure seal between the frame and elbow, reducing leakage and friction while maintaining affordability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If controlled clearance seal design is used to minimize leak, then sealing performance is improved, but manufacturing precision requirements increase and friction increases
Solution Approach 1:
The patent changes the physical state of the sealing element from rigid to flexible, allowing it to deform and adapt to tolerance variations. The flexible sealing element can compress and conform to the mating surfaces, maintaining effective sealing clearance even when manufacturing tolerances cause dimensional variations in the rigid components.
Solution Approach 2:
The flexible sealing element acts as an intermediary between the rigid frame and elbow components. It mediates the interface between parts with tolerance variations, absorbing dimensional discrepancies through elastic deformation while maintaining the sealing function, thereby reducing the stringency of manufacturing precision requirements.
2Reliability
If smaller clearance is used to reduce leak, then sealing performance is improved, but friction increases during rotation
Solution Approach 1:
The sealing contact is localized to specific regions on the flexible element rather than across the entire interface. The flexible sealing element concentrates the sealing function at discrete contact points or zones, allowing rotation to occur with minimal friction while maintaining effective sealing at the critical interfaces.
Solution Approach 2:
The flexible sealing element dynamically adapts its contact characteristics during rotation. As the elbow rotates, the flexible element continuously deforms to maintain optimal contact pressure for sealing while allowing smooth rotational motion, balancing sealing performance with low friction operation.
3Reliability
If flexible sealing element is added to reduce leak, then sealing performance is improved, but device complexity increases
Solution Approach 1:
The patent employs a flexible sealing element in the form of a thin, compliant component that integrates into the existing joint structure. This flexible element provides effective sealing without requiring complex multi-component assemblies, maintaining relative simplicity while significantly improving sealing performance compared to rigid controlled-clearance designs.
4Reliability
If tighter tolerances are specified for polypropylene parts, then sealing performance is improved, but manufacturing cost increases
Solution Approach 1:
The patent changes the material property parameter of the sealing element from rigid to flexible, which fundamentally alters the tolerance requirements. The flexible sealing element's ability to deform allows the use of standard, more economical polypropylene molding tolerances while achieving superior sealing performance, thereby reducing manufacturing costs.
Solution Approach 2:
The flexible sealing element serves as an intermediary that decouples sealing performance from tight manufacturing tolerances. By introducing this compliant component, the system can use cost-effective polypropylene parts with standard tolerances while the flexible element compensates for dimensional variations, maintaining effective sealing without premium manufacturing costs.
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 solution effectively minimizes air leaks and allows for smooth rotation of the swivel connector, achieving a reliable seal without the need for additional sealing components, thus reducing production costs and improving usability.
Implementation Method 1
one of the elbow and elbow-receiving portion includes a flexible element that upon assembly flexes to introduce a preload that effects a seal between the respective interlocking sealing portions
Data Source
AI summary
A mask assembly for use in providing a supply of air at positive pressure to the airways of a patient includes a frame and an elbow. The elbow is rotatable with respect to the frame when assembled. The frame includes an elbow-receiving portion. The elbow and elbow-receiving portion of the frame are adapted to include respective interlocking sealing portions and one of the elbow and elbow-receiving portion includes a flexible element that upon assembly flexes to introduce a preload that effects a seal between the respective interlocking sealing portions.