Elliptical Sleeve Bolt Connection for Hole Misalignment Alignment

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing connection systems in the aeronautical sector struggle with misalignment issues, difficulty in load control during assembly and dismantling, and require access to both sides for installation, leading to complex and heavy solutions that do not efficiently absorb structural loads.

Innovation Solution

A connection system with a threaded bolt and a sleeve having an elliptical cross-section transition, allowing for misalignment correction and gradual load transfer, enabling assembly and dismantling from one side, and facilitating multiple cycles.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If a threaded bolt connection is used, then the connection can be dismantled from one side, but it cannot absorb misalignments between holes

Engineering Contradiction:

Improvedismantling accessVSAvoidmisalignment absorption

Core Design Contradiction:

Ease of operationVSAdaptability or versatility

Solution Approach 1:

The connection system is divided into two functional parts: a threaded bolt for one-sided dismantling and an elliptical sleeve for misalignment absorption. This segmentation allows each component to specialize in its function while working together as a unified system.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The elliptical sleeve acts as an intermediary element between the threaded bolt and the structural elements. It mediates the misalignment issue by providing a geometric transformation that converts the circular hole intersection into an elliptical path, allowing the bolt to pass through even when holes are misaligned.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Ease of manufacture

If clearance fit connections are used, then assembly is simplified, but load transfer is poor due to loose fit

Engineering Contradiction:

Improveassembly simplicityVSAvoidload transfer capacity

Core Design Contradiction:

Ease of manufactureVSStrength

Solution Approach 1:

The sleeve's cross-sectional geometry changes from elliptical at the rear to circular at the front. This parameter change allows the sleeve to initially accommodate misaligned holes with clearance fit for easy assembly, then progressively align the holes as insertion proceeds, resulting in optimal load transfer at the final position.

Inventive Principle:

Principle #35Parameter changes

3Adaptability or versatility

If conical sleeve fixings are used, then slight misalignments can be absorbed, but the holes must be conical which complicates manufacturing

Engineering Contradiction:

Improvemisalignment absorptionVSAvoidhole preparation

Core Design Contradiction:

Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

The sleeve employs an asymmetric cross-sectional shape (elliptical to circular transition) instead of a symmetric conical shape. This asymmetry provides misalignment absorption capability while maintaining cylindrical holes in the structural elements, simplifying manufacturing compared to conical hole requirements.

Inventive Principle:

Principle #4Asymmetry

Data Source

PatentUS20250327470A1Connection system with an elliptical cross-section

Publication Date: 2025.10.23 AIRBUS OPERATIONS SL

AI summary

A connection system for connection between a front element and a rear element, comprising a threaded bolt with a rear portion and a front portion, a sleeve concentrically around the threaded bolt which is tapered towards the rear portion of the threaded bolt, a housing for the sleeve, and a fastening element configured to be threaded with the threaded bolt. The sleeve has a generally elliptical rear cross-section.