Piezo Nebulizer Liquid Exchange for Temperature Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Piezo electric crystal-based nebulizers generate heat, causing a temperature rise in the nebulization chamber and the liquid being nebulized, which can be undesirable for temperature-sensitive drugs.

Innovation Solution

An aerosol generating device that exchanges a portion of the liquid in the nebulization chamber with cooler liquid from a reservoir, using pumping and temperature sensing means to manage temperature, and optionally includes cooling mechanisms like a Peltier element or heat sink to maintain the liquid within specified temperature limits.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If a piezo electric crystal is used to vibrate the liquid or mesh for nebulization, then aerosol generation efficiency is improved, but the temperature of the liquid increases due to heat generation from the crystal

Engineering Contradiction:
Improveaerosol generation efficiencyVSAvoidliquid temperature
Core Design Contradiction:
ProductivityVSTemperature

Solution Approach 1:

The liquid system is divided into two separate portions: a first portion contained in the nebulization chamber that is heated by the piezo electric crystal, and a second portion stored in a separate reservoir that remains cooler. This segmentation allows each portion to serve its specific function while avoiding temperature mixing issues.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The cooler liquid from the reservoir is extracted and used to replace the heated liquid in the nebulization chamber. This extraction of the cooler portion and its application to the heated portion effectively removes the temperature problem from the nebulization process.

Inventive Principle:
Principle #2Taking out (Extraction)

2Productivity

If the piezo electric crystal operates continuously for efficient nebulization, then aerosol production is maintained, but heat accumulation causes excessive temperature rise

Engineering Contradiction:
Improveaerosol production rateVSAvoidheat accumulation
Core Design Contradiction:
ProductivityVSObject-generated harmful factors

Solution Approach 1:

The heated liquid portion in the nebulization chamber is discarded (exchanged) and replaced with cooler liquid from the reservoir. This discarding of the heated portion and recovery of the cooler portion creates a continuous cycle that prevents heat accumulation while maintaining aerosol production.

Inventive Principle:
Principle #34Discarding and recovering

Solution Approach 2:

The heat generated by the piezo electric crystal, which is normally a harmful byproduct, is effectively utilized by creating a temperature differential between the two liquid portions. This temperature difference becomes beneficial as it drives the liquid exchange mechanism, where cooler liquid replaces heated liquid to maintain optimal nebulization temperature.

Inventive Principle:
Principle #22Blessing in disguise (Convert harm into benefit)

3Duration of action of moving object

If the volume of the nebulization chamber is increased to hold more liquid, then operation duration is extended, but the temperature rise becomes more significant due to greater heat capacity

Engineering Contradiction:
Improveoperation durationVSAvoidtemperature rise magnitude
Core Design Contradiction:
Duration of action of moving objectVSTemperature

Solution Approach 1:

The total liquid volume is segmented between two containers: a smaller nebulization chamber for active nebulization and a larger reservoir for storing cooler liquid. This segmentation allows the system to extend operation duration by periodically exchanging liquid between the two portions, preventing excessive temperature rise in the chamber.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The reservoir is pre-filled with cooler liquid before the nebulization process begins. This preliminary preparation of the cooler liquid reserve allows the system to perform temperature compensation exchanges during operation, extending the duration of effective nebulization by preventing heat accumulation in the chamber.

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

Effectively reduces the temperature rise in the nebulization chamber, ensuring that temperature-sensitive drugs are nebulized within safe limits while maintaining efficient aerosol production.

Implementation Method 1

ultrasonic type nebulizers which use a piezo electric crystal to atomize the liquid received in a nebulization chamber

Methodology Applied
Scientific EffectPiezoelectric effect: Piezoelectric Effect

Implementation Method 2

the piezo electric crystal will transform part of the electrical energy offered at its terminals to mechanical movement and another part to heat

Methodology Applied
Scientific EffectJoule heating: Joule Heating

Implementation Method 3

the vibration means will produce heat causing the temperature of the nebulization chamber and the liquid contained therein to increase

Methodology Applied
Scientific EffectMechanical vibration: Vibration

Data Source

PatentEP2678059B1An aerosol generating device for nebulizing a liquid
Publication Date: 2021.04.07 KONINKLIJKE PHILIPS NV
  • EP2678059B1 patent drawingFigure 1
  • EP2678059B1 patent drawingFigure 2a~2b
  • EP2678059B1 patent drawingFigure 3

AI summary

An aerosol generating device (20) comprises a reservoir(1) for containing a liquid to be atomized and a nebulization chamber (3) for nebulizing a portion of the liquid received from the reservoir. The aerosol device further comprises liquid exchange means (7,8) for exchanging in use a further portion of the liquid received in the nebulization chamber with liquid from the reservoir to reduce a temperature increase of liquid in the nebulization chamber caused by heat produced by the piezo (4).