Air Spring Sleeve Structure for Hermetic Leak Prevention

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Air springs for vehicles face durability issues due to air leaks at attachment points, leading to reduced performance and increased manufacturing costs, especially in air suspension systems where the sleeve's design complexity and material limitations hinder efficient production and assembly.

Innovation Solution

A sleeve design comprising a first and second sleeve with a closed structure and reinforcement features, made from thermoplastic materials, where the second sleeve's end is hermetically fixed to an end cap, and the first and second sleeves are bonded using laser welding, allowing for reduced parts and improved manufacturing efficiency through injection molding, enhancing durability and design flexibility.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the sleeve is attached to surrounding parts using conventional methods, then the air spring can be assembled, but air leaks occur at the attachment portion leading to reduced durability

Engineering Contradiction:
ImprovedurabilityVSAvoidair leak
Core Design Contradiction:
ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent merges the attachment function directly into the sleeve structure by forming an integrated attachment portion that is molded as part of the sleeve body. This integration eliminates separate attachment components and their associated interfaces, thereby preventing air leaks at attachment points while maintaining assembly capability.

Inventive Principle:
Principle #5Merging (Combining)

2Reliability

If the sleeve design uses complex structures to prevent air leaks, then durability improves, but manufacturing costs increase

Engineering Contradiction:
ImprovedurabilityVSAvoidmanufacturing cost
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The attachment portion is merged with the sleeve body in a single injection molding process, eliminating the need for separate components and assembly steps. This integrated design maintains durability by preventing air leaks while reducing manufacturing complexity and costs.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The attachment portion serves multiple functions: it provides structural support, enables mounting to surrounding parts, and creates hermetic sealing to prevent air leaks. This multi-functionality is achieved through a single molded feature rather than multiple separate components, reducing manufacturing complexity.

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

3Ease of manufacture

If the sleeve is designed as a single integrated component, then manufacturing is simpler, but design freedom is limited

Engineering Contradiction:
Improvemanufacturing simplicityVSAvoiddesign freedom
Core Design Contradiction:
Ease of manufactureVSAdaptability or versatility

Solution Approach 1:

The sleeve design incorporates segmented features including the attachment portion with its distinct geometry and the reinforcement portion as separate molded regions. These segments are integrated into the single molded piece but maintain design independence, allowing optimization of each region's function while preserving overall manufacturing simplicity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The design applies local quality by providing reinforcement portions at specific locations where structural support is needed, and by giving the attachment portion its specific geometry only where mounting is required. This localized feature differentiation enhances design freedom within the constraints of single-piece molding.

Inventive Principle:
Principle #3Local quality

4Strength

If reinforcement portions are added to the sleeve, then structural strength improves, but the number of parts increases

Engineering Contradiction:
Improvestructural strengthVSAvoidnumber of parts
Core Design Contradiction:
StrengthVSDevice complexity

Solution Approach 1:

The reinforcement portions are merged into the sleeve body as integrated molded features rather than separate components. This provides the necessary structural strength at critical locations while maintaining the benefit of a single-piece construction, thereby avoiding an increase in the number of parts.

Inventive Principle:
Principle #5Merging (Combining)

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 solution effectively suppresses air leaks, improves durability, reduces manufacturing costs, and enhances the design freedom and quality of air spring sleeves, leading to improved vehicle ride quality and stability while simplifying the manufacturing process.

Implementation Method 1

the first and second sleeves are bonded using laser welding

Methodology Applied
Scientific EffectLaser welding: Laser Beam Welding

Data Source

PatentEP4474177A1Sleeve for air spring for vehicle
Publication Date: 2024.12.11 ILJIN CO LTD
  • EP4474177A1 patent drawingFigure 1
  • EP4474177A1 patent drawingFigure 2
  • EP4474177A1 patent drawingFigure 3

AI summary

A sleeve for an air spring for a vehicle includes at least a first sleeve (520) and a second sleeve (540). The first sleeve has both open ends and includes a first circumferential portion (522) and a second circumferential portion (524), the second sleeve has one open end and includes a third circumferential portion (542) coupled to the second circumferential portion of the first sleeve, and an end opposite the one open end of the second sleeve is formed in a closed structure (544).