Expiratory Valve Flow Path for Low-Noise Ventilator Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional expiratory valves in ventilators often produce loud noises and cause oscillating pressure fluctuations, leading to incorrect ventilation control and potentially harmful autotrigger or autocycle phenomena during mechanical ventilation.
Innovation Solution
The expiratory valve features a cup-shaped valve plenum with a fluid flow path that widens towards the outlet, a valve base with a convex shape, and stiffening ribs, designed to reduce turbulence and noise by adapting to the volume flow of exhaled air, enhancing sensitivity to phase changes and minimizing pressure setbacks.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a conventional expiratory valve design is used, then the valve can release exhaled air, but it generates loud noises and oscillating pressure fluctuations
Solution Approach 1:
The patent applies curvature by designing the fluid flow path with a convex shape that gradually widens from the fluid inlet to the fluid outlet. This curved, expanding geometry eliminates sharp edges and abrupt transitions, thereby reducing turbulence and the associated noise and pressure fluctuations while maintaining structural simplicity
Solution Approach 2:
The patent changes the geometric parameters of the fluid flow path by making it widen progressively from inlet to outlet. This parameter variation creates a smooth expansion that adapts to the volume flow of exhaled air, reducing turbulence and harmful noise without complicating the manufacturing process
2Measurement precision
If the valve responds sensitively to phase changes, then ventilation control accuracy improves, but pressure fluctuations may cause false triggering
Solution Approach 1:
The patent applies preliminary anti-action by designing the fluid flow path to minimize pressure fluctuations before they can cause false triggering. The convex, widening geometry preemptively reduces turbulence and pressure setbacks, preventing the conditions that would lead to autotriggering while maintaining sensitivity to genuine phase changes
3Ease of manufacture
If the fluid flow path has a constant cross-section, then manufacturing is simpler, but turbulence and noise increase
Solution Approach 1:
The patent replaces the constant cross-section design with a curved, expanding cross-section that widens from inlet to outlet. This curved geometry is manufacturable using standard techniques while effectively reducing turbulence and noise by eliminating abrupt flow transitions
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
This design significantly reduces noise generation and pressure reactions, improving the reliability and accuracy of ventilation control, thereby preventing premature initiation of inspiration phases and ensuring safer patient ventilation.
Implementation Method 1
a valve membrane which, depending on whether there is a sufficiently high overpressure on its side facing the airways compared to the pressure on its side facing away from the airways, opens or closes a fluid passage between the airways and the environment
Data Source
Figure 1
Figure 2~3
Figure 4
AI summary
The present invention relates to an expiratory valve (10) of a ventilator (100), comprising a valve body (12) in which a fluid inlet (14) and a fluid outlet (16) for the breathing air of a patient are formed, wherein the valve body (12) defines a fluid flow path between the fluid inlet (14) and the fluid outlet (16), the cross-section of which widens towards the fluid outlet (16).