Patient Interface Exhaust Venting With High-Drag Air Diffusion

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing patient interface exhaust ports cause discomfort by directing exhaled air onto the patient or bed partner and are difficult to clean, providing a potential for germ growth.

Innovation Solution

The design incorporates high-drag passages with textured surfaces, multiple bends, and narrow dimensions to slow airflow and diffuse exhaled gases, using modular components that can be easily cleaned and assembled.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a simple exhaust port design is used, then the device complexity is reduced, but the harmful effect of directing exhaled air onto the patient or bed partner increases

Engineering Contradiction:
Improveexhaust port designVSAvoidexhaled air discomfort
Core Design Contradiction:
Device complexityVSObject-affected harmful factors

Solution Approach 1:

The exhaust port is divided into multiple segments including an internal member with multiple inlets and an external member with multiple outlets arranged in a circular pattern. This segmentation allows the exhaust air to be distributed across multiple directions rather than a single direction, reducing the harmful effect of concentrated airflow onto the patient or bed partner.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The exhaust outlets are arranged in a circular pattern around the longitudinal axis of the gas delivery tube, transitioning from a linear or single-point exhaust to a three-dimensional radial distribution. This dimensional change disperses the exhaust air in multiple directions along the circumference, effectively reducing the concentration of harmful airflow in any single direction.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Object-affected harmful factors

If a mesh or fiber material is used to diffuse exhaust air, then the harmful effect of concentrated airflow is reduced, but the ease of cleaning deteriorates

Engineering Contradiction:
Improveexhaled air concentrationVSAvoidcleaning difficulty
Core Design Contradiction:
Object-affected harmful factorsVSEase of operation

Solution Approach 1:

The invention extracts and removes the problematic mesh or fiber diffusing material from the exhaust port design. Instead of using these difficult-to-clean materials, the patent employs smooth-walled internal and external members with geometrically defined passages, eliminating the cleaning difficulty while maintaining the air diffusion benefit through the circular outlet arrangement.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

Rather than using actual porous mesh or fiber materials that trap contaminants, the invention uses a geometric configuration of multiple outlets that achieves diffusion through spatial distribution. The smooth surfaces of the internal and external members allow for easy cleaning while the circular arrangement of outlets provides the necessary air dispersion without requiring porous structures.

Inventive Principle:
Principle #31Porous materials

3Speed

If high-drag passages with textured surfaces and multiple bends are used, then the airflow velocity is reduced for comfort, but the device complexity increases

Engineering Contradiction:
Improveairflow velocityVSAvoidpassage structure
Core Design Contradiction:
SpeedVSDevice complexity

Solution Approach 1:

The passages incorporate multiple bends and curved transitions rather than straight angular connections. These curved passages gradually change the airflow direction, reducing turbulence and velocity while maintaining smooth flow. The curvature allows for velocity reduction without requiring additional components or complex mechanisms.

Inventive Principle:
Principle #14Spheroidality (Curvature)

Solution Approach 2:

The internal member includes textured surfaces that change the friction characteristics of the passage walls. By modifying the surface parameters (roughness, texture pattern), the passage creates higher drag and reduces airflow velocity without changing the overall geometric configuration or adding complex structural elements.

Inventive Principle:
Principle #35Parameter changes

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 reduces airflow velocity and directs exhaled air away from the patient, enhancing comfort and hygiene by minimizing germ accumulation.

Implementation Method 1

high-drag passages with textured surfaces, multiple bends, and narrow dimensions to slow airflow

Methodology Applied
Scientific EffectFriction: Friction

Implementation Method 2

high-drag passages with textured surfaces, multiple bends, and narrow dimensions to slow airflow

Methodology Applied
Scientific EffectDrag: Drag

Data Source

PatentEP4221798B1Exhaust arrangement for patient interface device and patient interface including same
Publication Date: 2025.12.03 KONINKLIJKE PHILIPS NV
  • EP4221798B1 patent drawingFigure 1
  • EP4221798B1 patent drawingFigure 2~3
  • EP4221798B1 patent drawingFigure 4~5

AI summary

An arrangement (26) for exhausting gases from a cavity (20) of a patient interface (12) to an ambient environment, and a patient interface for use in providing a flow of treatment gas to the airway of a patient comprising such arrangement. The arrangement includes a body member (28) that forms a portion of the patient interface between the cavity and the ambient environment. The body member includes: - a number of inlets (30) defined in a first side of the body member for receiving gases from the cavity; - a number of outlets (32) defined in a second side of the body member opposite the first side for provide for the exit of gases from the patient interface to the surrounding environment; and - a number of high-drag passages (34) defined in the body member extending laterally between an inlet of the number of inlets and an outlet of the number of outlets.