Semiconductor Gas Sensor With Oxidation-Based Baseline Reset

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing gas detection devices struggle to reliably detect low concentrations of combustible gases under varying ambient conditions without requiring frequent recalibration and are influenced by environmental factors.

Innovation Solution

A gas detection device and method that uses an oxidizing component to oxidize combustible gases in a measuring chamber, allowing for the determination of a current zero point by measuring the detection variable before and after oxidation, thereby eliminating the need for continuous recalibration and reducing the impact of ambient conditions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a gas sensor is operated continuously in a small measurement volume, then measurement reliability is improved, but baseline drift and environmental influence worsen

Engineering Contradiction:
Improvemeasurement reliabilityVSAvoidbaseline stability
Core Design Contradiction:
ReliabilityVSMeasurement precision

Solution Approach 1:

The patent implements periodic switching between two operating modes: a measurement mode where the sensor operates continuously in a small measurement volume, and a regeneration mode where the baseline is reset. This periodic action allows the system to maintain measurement reliability while periodically eliminating baseline drift and environmental influences through controlled purging or resetting of the measurement chamber.

Inventive Principle:
Principle #19Periodic action

2Reliability

If the measurement volume is reduced to improve sensor operation, then sensor reliability is improved, but environmental sensitivity worsens

Engineering Contradiction:
Improvesensor operation reliabilityVSAvoidenvironmental influence
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The measurement system is segmented into two distinct functional spaces: a small measurement volume optimized for sensor operation with reduced environmental sensitivity, and a larger regeneration volume used for baseline resetting. This segmentation allows the sensor to operate reliably in the protected small volume while periodically moving to the larger volume for environmental reset, thus resolving the contradiction between sensor reliability and environmental sensitivity.

Inventive Principle:
Principle #1Segmentation

3Measurement precision

If frequent recalibration is performed to maintain accuracy, then measurement precision is improved, but operational complexity and time loss worsen

Engineering Contradiction:
Improvedetection accuracyVSAvoidrecalibration time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The system performs self-calibration by automatically switching between measurement and regeneration modes. During regeneration mode, the measurement chamber is purged or reset, automatically restoring the baseline without requiring manual intervention or external calibration equipment. This self-service approach maintains measurement precision while eliminating the time loss and operational complexity associated with frequent manual recalibration.

Inventive Principle:
Principle #25Self-service

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 reliable detection of low concentrations of combustible gases with reduced false alarms and minimal environmental influence, maintaining accuracy under changing conditions without the need for continuous recalibration.

Implementation Method 1

The switched-on oxidation component oxidizes flammable target gas in the measuring chamber

Methodology Applied
Scientific EffectOxidation: Oxidation

Implementation Method 2

the value of the detection variable of the sensor component is greater, the lower the concentration of the combustible target gas

Methodology Applied
Scientific EffectElectrical Resistance: Electrical Resistance

Data Source

PatentEP4266034B1Gas detection device and gas detection method using a sensor component and an oxidation component
Publication Date: 2025.08.27 DRAGER SAFETY AG & CO KAAA
  • EP4266034B1 patent drawingFigure 1
  • EP4266034B1 patent drawingFigure 2
  • EP4266034B1 patent drawingFigure 3

AI summary

A gas detection device (100) and a method for monitoring an area for a flammable target gas. A gas sample (G) from the area enters a measuring chamber. A semiconductor sensor (1) comprises an electrically conductive sensor component (10) that has an electrical detection value. In one implementation, this value is larger, and in another, it is smaller, as the concentration of the flammable target gas in the measuring chamber (9) decreases. An oxidizing component (2) is capable of oxidizing the flammable target gas in the measuring chamber. At a detection time, the detection value is measured, and the oxidizing component (2) is or is switched on. Up to a reference time, the oxidizing component (2) oxidizes at least a portion of the flammable target gas in the measuring chamber (9). At the reference time, the detection value is measured again.The difference between the measurement at the reference time and the measurement at the detection time is a measure of the concentration of flammable target gas in the measuring chamber (9).