Nebulizer Membrane Fluid Detection Using Multi-Frequency Vibration

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing aerosol delivery devices struggle to reliably and efficiently detect the presence of fluid for aerosolization, particularly in inhalation nebulizers, due to sensitivity to structural and environmental factors affecting electrical parameters, which can lead to inaccurate detection and potential damage to piezoelectric elements.

Innovation Solution

An aerosol delivery device with a vibratable membrane and a vibrator that operates at multiple frequencies, using a sensor to detect electrical parameters and analyze their frequency dependence to reliably determine fluid presence, minimizing signal variations from structural and environmental factors.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a single-frequency electrical parameter detection method is used, then the detection process is simple, but the detection accuracy is low due to sensitivity to structural and environmental factors

Engineering Contradiction:
Improvefluid presence detection accuracyVSAvoiddetection system complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent applies dynamics by transitioning from a static single-frequency detection method to a dynamic multi-frequency detection approach. The system sequentially operates the vibrator at multiple different vibration frequencies and analyzes the frequency dependence of electrical parameters, allowing the detection method to adapt to varying structural and environmental conditions through frequency variation.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent implements parameter changes by varying the vibration frequency parameter during detection. Instead of using a fixed frequency, the system changes the operating frequency across multiple values and analyzes how electrical parameters respond to these frequency changes, thereby identifying fluid presence more reliably despite structural and environmental variations.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If the vibrator operates continuously at high power, then complete aerosol delivery is ensured, but power consumption increases and battery lifetime decreases

Engineering Contradiction:
Improveaerosol delivery completenessVSAvoidpower consumption
Core Design Contradiction:
ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent applies preliminary action by performing fluid presence detection before initiating aerosol generation. This preliminary check ensures that the vibrator only operates when fluid is actually present, preventing unnecessary power consumption and battery drain while maintaining reliable aerosol delivery when needed.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The system implements feedback by using detected electrical parameter frequency dependence to control vibrator operation. The detection results feed back into the control logic to determine whether to activate and sustain aerosol generation, optimizing power usage based on actual fluid presence conditions.

Inventive Principle:
Principle #23Feedback

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

Enables accurate and efficient detection of fluid presence, ensuring complete aerosol delivery and preventing device damage, while optimizing power usage and patient adherence.

Implementation Method 1

an oscillation generator, for example, a piezocrystal

Methodology Applied
Scientific EffectPiezoelectric effect: Piezoelectric Effect

Implementation Method 2

an ultrasonic liquid nebuliser having a piezocrystal which is caused to oscillate electrically by an oscillator circuit

Methodology Applied
Scientific EffectUltrasonic vibration: Ultrasonic Vibration

Data Source

PatentEP4434588B1Aerosol delivery device
Publication Date: 2026.04.08 PARI PHARMA GMBH
  • EP4434588B1 patent drawingFigure 1
  • EP4434588B1 patent drawingFigure 2(a)~2(b)
  • EP4434588B1 patent drawingFigure 3~4

AI summary

An aerosol delivery device (A) comprising an aerosol generator for generating an aerosol in the aerosol delivery device, the aerosol generator comprising a membrane (1), and a vibrator (7), which is configured to vibrate a fluid and to aerosolise the fluid by the membrane (1), a fluid reservoir (2) for receiving the fluid (3) to be aerosolised, the fluid reservoir (2) being arranged in fluid communication with the membrane (1), a controller (10) which is configured to sequentially operate the vibrator (7) at a plurality of different vibration frequencies, a sensor (13) which is configured to detect at least one electrical parameter of the vibrator (7) for each of the plurality of different vibration frequencies, and a detector (13a) which is configured to detect the presence of fluid (3) in contact with the membrane (1) and/or in the fluid reservoir (2) on the basis of the dependence of the detected values of the at least one electrical parameter on the vibration frequency, wherein the detector (13a) is configured to detect the presence of fluid (3) in contact with the membrane (1) and/or in the fluid reservoir (2) on the basis of the area under a curve of the detected values of the at least one electrical parameter as a function of the vibration frequency, and/or a Fourier transform of a curve of the detected values of the at least one electrical parameter as a function of the vibration frequency.