Oil Mist Detector Optical Sensor Dual Light Measurement

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing oil mist detectors face challenges in reliably detecting fine oil droplets in air mixtures, particularly in differentiating between oil mist and water mist, which can lead to false alarms and compromised safety in environments like internal combustion engines, where fine oil droplets can form potentially explosive mixtures.

Innovation Solution

The oil mist detector employs a dual measurement approach using both transmitted and scattered light measurements with redundant optical paths and detectors, allowing for simultaneous evaluation of light sources and detectors to differentiate between oil and water droplets based on their scattering properties, and incorporates a bypass system to separate larger droplets from the measurement chamber, ensuring only smaller droplets are detected for accurate analysis.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If only transmitted light measurement is used, then the detection of oil mist is simplified, but the ability to differentiate between oil mist and water mist is insufficient leading to false alarms

Engineering Contradiction:
Improvemeasurement system complexityVSAvoiddetection accuracy
Core Design Contradiction:
Device complexityVSReliability

Solution Approach 1:

The patent combines transmitted light measurement and scattered light measurement into a single detection system. The evaluation unit processes both measurement types simultaneously to differentiate between oil mist and water mist, reducing false alarms while maintaining system integration and avoiding excessive complexity.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The optical measurement system performs multiple functions: it measures both transmitted light intensity and scattered light intensity using the same light source and detector arrangement. This multi-functionality enables differentiation between oil and water droplets without requiring separate measurement systems.

Inventive Principle:
Principle #6Universality (Multi-functionality)

2Measurement precision

If scattered light measurement is added to transmitted light measurement, then the differentiation between oil mist and water mist improves, but the device complexity increases

Engineering Contradiction:
Improvedroplet identification accuracyVSAvoidoptical measurement system complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent merges transmitted light measurement and scattered light measurement into a unified system. Both measurements are performed simultaneously using the same light source and detector, with the evaluation unit processing both signals to identify droplet type. This integration improves measurement precision without proportionally increasing device complexity.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The optical measurement system is designed to perform multiple measurement functions simultaneously. The same light source and detector arrangement are used for both transmitted light intensity measurement and scattered light intensity measurement, making the system multi-functional and efficient.

Inventive Principle:
Principle #6Universality (Multi-functionality)

3Device complexity

If all droplets are measured without separation, then the measurement process is simplified, but larger droplets interfere with the detection of fine oil droplets reducing accuracy

Engineering Contradiction:
Improvedroplet separation system complexityVSAvoidfine droplet detection accuracy
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent segments the droplet population by size using a separation unit that divides droplets into different size ranges. Fine droplets (including oil mist) are separated from larger droplets, allowing the optical measurement system to focus on detecting fine droplets without interference from larger ones, thereby improving measurement precision.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The separation unit extracts fine droplets from the mixed droplet population. By taking out the fine droplets that are relevant for explosion hazard detection and separating them from larger droplets, the system improves the accuracy of fine droplet detection while maintaining a relatively simple overall structure.

Inventive Principle:
Principle #2Taking out (Extraction)

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 solution enhances the reliability of detecting potentially explosive oil-air mixtures by reducing false alarms and improving the accuracy of identifying fine oil droplets, thereby increasing operational safety and extending maintenance intervals.

Implementation Method 1

the measuring chamber has an optical measuring arrangement of light sources and light detectors, and that this optical measuring arrangement is configured to carry out a simultaneous transmitted light measurement and a scattered light measurement

Methodology Applied
Scientific EffectAbsorption (EM radiation): Absorption (EM radiation)

Implementation Method 2

the use of an additional scattered light measurement provides additional measurement parameters that allow differentiation between signals originating from oil droplets and those caused by water mist. The reason for this is that water mist and oil mist scatter light to different degrees.

Methodology Applied
Scientific EffectScattering: Scattering

Data Source

PatentEP4237831B1Oil-mist detector having an optical sensor for detection and/or analysis of oil-air mixtures and corresponding method
Publication Date: 2024.07.03 HEINZMANN GMBH & CO KG
  • EP4237831B1 patent drawingFigure 1~3
  • EP4237831B1 patent drawingFigure 4~8
  • EP4237831B1 patent drawingFigure 9~10

AI summary

In order to improve the measurement reliability and measurement precision of an oil mist detector (1) for detecting and/or analyzing potentially explosive oil-air mixtures, a combination of a redundant transmitted light measurement (6, 72) and a scattered light measurement (73, 74, 75, 76), preferably a likewise redundant scattered light measurement, are simultaneously used in order to optically detect fine oil droplets.