Segmented Cushion Voids for CPAP Seal and Pressure Distribution
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional patient interface device cushions provide uniform deformation, which may not optimally seal the face, leading to suboptimal delivery of breathing gas during non-invasive ventilation and pressure support therapies, such as CPAP for obstructive sleep apnea treatment.
Innovation Solution
A cushion with a patient contacting portion, a middle portion featuring multiple voids and orifices, and a connection portion, made from a material with a hardness of 5-60 Shore 00 scale, designed to provide controlled deformation and collapse, enhancing the seal and comfort by reducing pressure points and weight.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a unitary top flap design is used for the cushion, then the structure is simple and easy to manufacture, but the deformation is uniform and does not provide optimal seal for different portions of the patient's face
Solution Approach 1:
The cushion is divided into multiple independent flaps (first flap, second flap, third flap, fourth flap) instead of a single unitary structure. Each flap can deform independently to conform to different facial contours, providing optimized sealing for various portions of the patient's face while maintaining manufacturing simplicity through modular construction.
Solution Approach 2:
Each flap is equipped with its own void structure, allowing different regions of the cushion to have different deformation characteristics. The voids in each flap can be independently designed to provide appropriate compliance and sealing pressure for the specific facial area it contacts, achieving local optimization of seal quality.
2Strength
If the wall portions are made thicker to provide support, then the structural strength increases, but the weight increases and pressure points are not reduced
Solution Approach 1:
The wall portions incorporate voids (cavities or channels) within the material structure, creating a porous or cellular configuration. This reduces the overall density and weight of the cushion while maintaining structural support through the geometric configuration of the voids, which allow the material to deform and distribute pressure more effectively.
Solution Approach 2:
The voids are designed with curved or rounded geometries that allow the wall portions to flex and deform in a controlled manner. This curved structure within the walls provides structural support while enabling the cushion to conform to facial contours, reducing pressure points without requiring excessive material thickness.
3Stability of the object's composition
If the material hardness is increased to provide better support, then the structural stability improves, but the comfort decreases due to increased pressure points on the patient's face
Solution Approach 1:
The cushion uses material with moderate hardness (5-30 Shore 00) rather than very hard material, and combines this with a specific void configuration. This parameter change allows the cushion to be soft enough to comfort the patient's face while the void structure provides the necessary support and deformation control to maintain stability during use.
Solution Approach 2:
The voids are strategically positioned within the wall portions to provide pre-planned deformation zones. These voids act as built-in cushioning elements that allow the cushion to yield and conform to the patient's facial contours before contact pressure becomes excessive, preventing pressure points while maintaining overall structural stability.
4Reliability
If multiple voids are added to the wall portions to provide controlled deformation, then the seal quality improves, but the device complexity increases
Solution Approach 1:
The cushion is divided into multiple independent flaps, each with its own void structure. This segmentation allows each flap to be independently designed and manufactured, simplifying the overall production process while achieving complex deformation behavior through the coordinated action of multiple simple modular units.
Solution Approach 2:
The voids are integrated into the wall portions as inherent features of the molded structure rather than as separate components. This porous configuration is created in a single manufacturing step, avoiding the need for complex assembly operations and reducing device complexity despite the presence of multiple deformation zones.
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 cushion achieves a more secure and comfortable seal, reducing pressure points and strapping force requirements, improving the efficacy of respiratory therapies by allowing for even pressure distribution and minimizing facial discomfort.
Implementation Method 1
the cushion achieves a more secure and comfortable seal, reducing pressure points and strapping force requirements, improving the efficacy of respiratory therapies by allowing for even pressure distribution
Data Source
Figure 1~2
Figure 3
Figure 4~5
AI summary
A cushion (10, 30, 56) for a patient interface device includes a patient contacting portion (12, 32, 60) and wall portions (18, 20, 22, 24, 34, 66, 68, 70, 72). The wall portions include a plurality of voids (26, 74) and/or orifices therein. The patient contacting portion and the wall portions may be made of a material having a hardness of between 5 and 60 on the Shore 00 scale. Also, the parts of the wall not having the plurality of voids/orifices provided therein may have a cross-sectional thickness of 4 mm or greater. The voids may include a first void provided in an inner side of a first one of the wall portions and a second void provided in an outer side of the first one of the wall portions. The first void and the second void are positioned across from and overlapping one another.