One-Piece Duct Tube Cap With Self-Retaining Bead Groove

Solution Overview

Problem

Current caps used to close off unneeded duct tubes in aircraft environmental control systems are expensive and time-consuming to install due to their two-piece construction, which includes a cap and an adjustable band, requiring manual positioning and tightening for each duct tube.

Innovation Solution

A one-piece cap construction made of resilient material with a cylindrical configuration, featuring a groove for receiving a bead on the duct tube, conical section for guiding the duct tube, and pull tabs for easy installation, which reduces production costs and installation time.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a two-piece construction with adjustable band is used, then the cap can be securely attached to the duct tube, but the production cost increases and installation time increases

Engineering Contradiction:

Improvesecure attachmentVSAvoidtwo-piece construction

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent combines the cap body and retention mechanism into a single integrated one-piece construction. The cap includes an integrally formed body with a retention feature that engages with the duct tube bead, eliminating the need for a separate adjustable band while maintaining secure attachment capability.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent extracts the adjustable band component from the cap assembly, removing the complex two-piece construction. The retention function is achieved through an integrally formed retention feature on the cap body itself, which engages with the bead on the duct tube without requiring additional components.

Inventive Principle:

Principle #2Taking out (Extraction)

2Reliability

If a two-piece construction with adjustable band is used, then the cap can be securely attached to the duct tube, but the production cost increases

Engineering Contradiction:

Improvesecure attachmentVSAvoidproduction cost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The patent combines the cap body and retention mechanism into a single integrated one-piece construction. The cap includes an integrally formed body with a retention feature that engages with the duct tube bead, eliminating the need for a separate adjustable band while maintaining secure attachment capability.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent employs a simple one-piece cap construction that can be manufactured more economically than the two-piece design. The integrally formed cap with built-in retention feature reduces material costs and manufacturing complexity, making it a more cost-effective solution for securing duct tubes.

Inventive Principle:

Principle #27Cheap short-living objects (Disposable)

3Reliability

If a two-piece construction is used, then the cap can be securely attached to the duct tube, but the installation time increases

Engineering Contradiction:

Improvesecure attachmentVSAvoidinstallation time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The patent combines the cap body and retention mechanism into a single integrated one-piece construction. The cap includes an integrally formed body with a retention feature that engages with the duct tube bead, eliminating the need for a separate adjustable band while maintaining secure attachment capability.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The patent designs the cap with an integrally formed retention feature that automatically engages with the bead on the duct tube during installation. The conical guide surface facilitates self-alignment and automatic engagement, eliminating the need for manual adjustment and tightening operations required by the adjustable band design.

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 one-piece cap design lowers production costs and simplifies the installation process by allowing the cap to be securely attached to the duct tube without the need for an adjustable band, reducing the time required to secure multiple caps on multiple duct tubes.

Implementation Method 1

The side wall being resilient enables the cylindrical configuration of the interior surface of the side wall to expand radially outwardly as the bead around the end of the duct tube is moved through the conical section of the side wall and into the interior surface of the side wall

Methodology Applied

Scientific EffectElasticity: Elasticity

Data Source

PatentUS11378216B2Cap having a low cost construction and a self retaining feature

Publication Date: 2022.07.05 THE BOEING CO

AI summary

A cap for closing an open end of a duct tube has a cylindrical side wall having a length between a closed end and an open end of the side wall. An end wall extends across the closed end of the side wall. A conical section of the side wall extends outwardly from the open end of the side wall and has an interior surface configured to guide an end of a duct tube into a hollow interior volume of the side wall. A groove in an interior surface of the side wall is configured to receive a bead around an end of a duct tube inserted through the conical section and into the hollow interior of the side wall. A plurality of pull tabs extend outwardly from the conical section and are configured to be manually pulled, pulling the cap over the end of the duct tube.