Gas Generator Sealing Structure for Moisture-Resistant Assembly

Solution Overview

Problem

Existing gas generators face issues with moisture absorption of the gas generating agent due to multiple air paths, leading to potential deterioration and increased assembly complexity from the use of additional parts like O-rings or sealing materials.

Innovation Solution

A gas generator design with a housing containing an activation gas generation chamber and a filter chamber, using a side surface cover welded to the housing and holder to restrict air passages, reducing the need for additional sealing components and simplifying assembly.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If multiple air paths are provided between the internal space and outside of the housing, then the gas generating agent can be easily accessed for ignition, but moisture absorption of the gas generating agent deteriorates

Engineering Contradiction:

Improveignition accessibilityVSAvoidmoisture resistance

Core Design Contradiction:

Ease of operationVSReliability

Solution Approach 1:

The housing internal space is segmented into multiple chambers (first internal space, second internal space, third internal space) with controlled air paths. The gas generating agent is divided into multiple portions (first, second, third portions) located in different chambers, allowing selective access while limiting overall exposure to moisture.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different regions of the housing have different sealing qualities. The holder and closing member create localized sealed environments around the gas generating agent portions, while still allowing necessary access for ignition. The filter chamber provides localized filtration without compromising overall sealing.

Inventive Principle:

Principle #3Local quality

2Reliability

If sealing materials like O-rings are added to suppress moisture absorption, then moisture resistance improves, but the number of parts increases and assembly complexity worsens

Engineering Contradiction:

Improvemoisture resistanceVSAvoidnumber of parts

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The sealing function is merged into the structural components themselves. The holder and closing member are designed with integrated sealing features that combine the structural support and moisture barrier functions into single components, eliminating the need for separate O-rings or gaskets.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The housing structure provides its own sealing through the design of the holder and closing member interfaces. The components create sealed chambers through their geometric configuration and mating surfaces, making the system self-sealing without requiring additional sealing materials.

Inventive Principle:

Principle #25Self-service

3Reliability

If sealing materials like O-rings are added to suppress moisture absorption, then moisture resistance improves, but assembly process complexity worsens

Engineering Contradiction:

Improvemoisture resistanceVSAvoidassembly ease

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The sealing function is merged into the structural components themselves. The holder and closing member are designed with integrated sealing features that combine the structural support and moisture barrier functions into single components, eliminating the need for separate O-rings or gaskets.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The housing structure provides its own sealing through the design of the holder and closing member interfaces. The components create sealed chambers through their geometric configuration and mating surfaces, making the system self-sealing without requiring additional sealing materials.

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

The design effectively suppresses moisture absorption of the gas generating agent and reduces the number of parts, making assembly easier while maintaining functionality.

Implementation Method 1

an activation gas generation chamber in which an activation gas is generated by combustion of a gas generating agent

Methodology Applied

Scientific EffectCombustion: Combustion

Implementation Method 2

a portion of a side surface of the holder corresponding to the portion are subjected to welding fixation annularly along a circumferential direction of the housing

Methodology Applied

Scientific EffectWelding: Welding

Data Source

PatentUS20260014957A1Gas generator

Publication Date: 2026.01.15 NIPPON KAYAKU CO LTD

AI summary

There is obtained a gas generator that can suppress deterioration due to moisture absorption of a gas generating agent in a housing, can reduce the number of parts, and can be easily assembled as compared with the related art. A gas generator includes a housing, a holder attached to one opening end of the housing, a closing member attached to another end of the housing so as to close another opening end of the housing, and a side surface cover covering a part of the holder and a part of an igniter. The side surface cover has an end welded and fixed to the housing and the holder at a welded fixed portion in a state of being sandwiched between an inner wall of the housing and a side surface portion. The welded fixed portion is formed in an annular shape along the circumferential direction of the housing by being subjected to welding processing from the outside of the housing along a circumferential direction of the housing at a position corresponding to the side surface portion covered by the side surface cover.