Gas Sensor Element With Gas-Permeable Connecting Segment

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing gas sensors face accuracy deterioration due to external gases entering the sensor element through gaps, affecting the detection of specific gas concentrations.

Innovation Solution

The sensor element is designed with a conducting section that includes an inner conducting section and an outer conducting section, where the inner conducting section has a routing part that exits to the peripheral face, and the outer conducting section has a connecting segment with gas permeability, or a portion of the routing part is exposed outside, with a perimeter sum less than 1.30 mm to minimize gas entry.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the inner section of the lead is disposed inside the element body with a gap between its outer periphery and the element body, then electrical connection is established, but external gases can enter through the gap and reach the inner electrode, deteriorating detection accuracy

Engineering Contradiction:

Improveelectrical connection reliabilityVSAvoidgas concentration detection accuracy

Core Design Contradiction:

ReliabilityVSMeasurement precision

Solution Approach 1:

The patent applies a gas-permeable membrane (thin film structure) that covers the outer periphery of the routing part of the inner conducting section. This membrane is selectively permeable to oxygen ions while blocking external gases from reaching the inner electrode through the gap, thus maintaining electrical connection while preventing gas contamination.

Inventive Principle:

Principle #30Flexible shells and thin films

Solution Approach 2:

The gas-permeable membrane used in the patent has a porous structure that allows oxygen ions to pass through for electrical conduction while physically blocking external gases from entering the element body through the gap. The porous structure enables selective permeability based on molecular size and charge characteristics.

Inventive Principle:

Principle #31Porous materials

2Measurement precision

If the routing part of the inner conducting section has a large perimeter to ensure adequate exposure, then gas entry through gaps is reduced, but the overall size of the sensor element increases

Engineering Contradiction:

Improvegas detection accuracyVSAvoidsensor element size

Core Design Contradiction:

Measurement precisionVSVolume of moving object

Solution Approach 1:

By covering the routing part with a gas-permeable membrane, the patent eliminates the need for large exposed perimeters to prevent gas entry. The membrane provides gas blocking functionality regardless of the routing part's dimensions, allowing the sensor element to maintain compact size while preserving detection accuracy.

Inventive Principle:

Principle #30Flexible shells and thin films

3Reliability

If the connecting segment has gas permeability to allow oxygen ion passage, then electrical conductivity is maintained, but external gases may still enter through gaps between the inner section and element body

Engineering Contradiction:

Improveelectrical conductivityVSAvoidexternal gas contamination

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The gas-permeable membrane acts as an additional barrier layer that specifically blocks external gases from entering through gaps between the inner section and element body, while still allowing oxygen ions to pass through to maintain electrical conductivity in the sensing region.

Inventive Principle:

Principle #30Flexible shells and thin films

Solution Approach 2:

The gas-permeable membrane serves as an intermediary structure between the internal conducting sections and the external environment. It mediates the interaction by selectively allowing oxygen ions to pass while preventing harmful external gases from reaching the inner electrode, thus protecting the sensing function.

Inventive Principle:

Principle #24Intermediary (Mediator)

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 configuration reduces the likelihood of external gases reaching the inner electrode, thereby lowering the risk of accuracy deterioration in specific gas concentration detection.

Implementation Method 1

the connecting segment of the outer conducting section has gas permeability

Methodology Applied

Scientific EffectGas permeability: Permeation

Implementation Method 2

an element body including an oxygen-ion-conductive solid electrolyte layer

Methodology Applied

Scientific EffectOxygen-ion conduction: Fast Ion Conductor

Data Source

PatentUS20250164437A1Sensor element and gas sensor

Publication Date: 2025.05.22 NGK INSULATORS LTD

AI summary

A sensor element includes: an element body; a conducting section including an inner conducting section and an outer conducting section, the outer conducting section, being electrically continuous with the inner conducting section, wherein the outer conducting section includes a connecting segment connected to a routing part of the inner conducting section, wherein the connecting segment of the outer conducting section has gas permeability, and/or at least a portion of the routing part of the inner conducting section is exposed to an outside of the sensor element, and wherein an outer periphery of the routing part of the inner conducting section has a perimeter that is a sum of a first perimeter of a portion covered by the connecting segment having the gas permeability and a second perimeter of a portion exposed to the outside of the sensor element, the sum being shorter than 1.30 mm.