Ventilator Blower Speed Profiling for Stable Inlet Pressure

Solution Overview

Problem

Statically operated blowers in ventilators face challenges in maintaining constant pressure during ventilation due to pressure fluctuations, leading to inefficient gas delivery and increased energy consumption, noise, and wear.

Innovation Solution

A control unit dynamically adjusts the speed of a blower within a breathing cycle, temporarily increasing to a higher speed level before the inspiratory phase to maintain pressure and then reducing back to a lower level, ensuring constant pressure during gas delivery.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If a statically operated blower is used to reduce cost and wear, then manufacturing cost and blower wear are reduced, but the pressure fluctuates during ventilation and cannot be maintained constant

Engineering Contradiction:

Improvemanufacturing costVSAvoidpressure stability

Core Design Contradiction:

Ease of manufactureVSStability of the object's composition

Solution Approach 1:

The invention applies dynamics by enabling the blower to change its operating state from static to dynamic. The control unit temporarily increases the blower speed from a first level to a second level during the inspiratory phase, allowing the system to adapt pressure output to varying flow demands while maintaining constant pressure during gas delivery.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The invention uses periodic action by cycling the blower through different speed levels in sync with the breathing cycle. The control unit periodically increases blower speed before the inspiratory phase and reduces it during the expiratory phase, creating a rhythmic pattern that matches patient ventilation requirements and maintains stable pressure throughout.

Inventive Principle:

Principle #19Periodic action

2Stability of the object's composition

If the blower speed is continuously increased to maintain constant pressure, then pressure stability is improved, but energy consumption and noise increase

Engineering Contradiction:

Improvepressure stabilityVSAvoidenergy consumption

Core Design Contradiction:

Stability of the object's compositionVSUse of energy by moving object

Solution Approach 1:

The invention applies partial action by increasing the blower speed only to the extent necessary to maintain constant pressure during the inspiratory phase, rather than continuously operating at maximum speed. The control unit temporarily increases speed only during the brief period before and during inspiration, then reduces it during expiration, using just enough power to achieve the desired pressure stability.

Inventive Principle:

Principle #16Partial or excessive action

Solution Approach 2:

The invention uses preliminary action by increasing the blower speed in advance before the inspiratory phase begins. The control unit detects the upcoming inspiration and proactively increases the blower speed to build up pressure, ensuring constant pressure is maintained when gas delivery starts, then reduces speed after the phase completes.

Inventive Principle:

Principle #10Preliminary action

3Stability of the object's composition

If a dynamically operated blower is used to maintain constant pressure, then pressure stability is improved, but manufacturing cost and blower wear increase

Engineering Contradiction:

Improvepressure stabilityVSAvoidmanufacturing cost

Core Design Contradiction:

Stability of the object's compositionVSEase of manufacture

Solution Approach 1:

The invention applies dynamics by enabling the blower to change its operating state from static to dynamic. The control unit temporarily increases the blower speed from a first level to a second level during the inspiratory phase, allowing the system to adapt pressure output to varying flow demands while maintaining constant pressure during gas delivery.

Inventive Principle:

Principle #15Dynamics

Solution Approach 2:

The invention uses periodic action by cycling the blower through different speed levels in sync with the breathing cycle. The control unit periodically increases blower speed before the inspiratory phase and reduces it during the expiratory phase, creating a rhythmic pattern that matches patient ventilation requirements and maintains stable pressure throughout.

Inventive Principle:

Principle #19Periodic action

4Stability of the object's composition

If the blower operates at high speed continuously to compensate for pressure drops, then pressure stability is improved, but noise and energy consumption increase

Engineering Contradiction:

Improvepressure stabilityVSAvoidnoise

Core Design Contradiction:

Stability of the object's compositionVSObject-generated harmful factors

Solution Approach 1:

The invention applies partial action by increasing the blower speed only to the extent necessary to maintain constant pressure during the inspiratory phase, rather than continuously operating at maximum speed. The control unit temporarily increases speed only during the brief period before and during inspiration, then reduces it during expiration, using just enough power to achieve the desired pressure stability.

Inventive Principle:

Principle #16Partial or excessive action

Solution Approach 2:

The invention uses preliminary action by increasing the blower speed in advance before the inspiratory phase begins. The control unit detects the upcoming inspiration and proactively increases the blower speed to build up pressure, ensuring constant pressure is maintained when gas delivery starts, then reduces speed after the phase completes.

Inventive Principle:

Principle #10Preliminary action

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 approach maintains consistent pressure and volume flow, reduces energy consumption and noise, and minimizes blower wear, particularly benefiting battery-operated ventilators.

Implementation Method 1

a blower (1) which is configured to draw in (suck in) ambient air through an inlet (31), compress the ambient air and forward it on to a control valve (3)

Methodology Applied

Scientific EffectCompression: Compression

Implementation Method 2

The control unit (2) is configured to change the speed of the blower and thus influence the pressure and the volume flow of the ambient air drawn in

Methodology Applied

Scientific EffectSpeed control:

Data Source

PatentUS20250381360A1Device and process for generating an inlet pressure at a control valve of a ventilator

Publication Date: 2025.12.18 DRAGERWERK AG

AI summary

A device (10) generates an inlet pressure at a control valve of a ventilator (30) and includes a blower (1), a control unit (2) and the control valve (3). The blower is configured to draw in ambient air through an inlet (31), compress and forward it to the control valve. The control unit is configured to change a speed (N) of the blower and to operate the blower at a first speed level (n1) and determine a triggering time (t0) at which the speed of the blower is temporarily changed from the first speed level to a second speed level (n2) within a same breathing cycle of the ventilator. The first speed level is lower than the second speed level. A process for generating an inlet pressure (P) at the control valve as well as to the ventilator including the device and a computer program product are provided.