Vacuum-Formed Fitted Cap for Uniform Fastener Sealant Shrouds

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Manual brush application of sealant to fasteners is laborious, time-consuming, and lacks quality control, with existing sealant applicators requiring skilled operators and having inconsistent methods and traceability.

Innovation Solution

A system comprising a support plate, fastener template, precursor cap, and cap-manipulation tool, where a polymer sheet is heated and vacuum-formed to create a fitted cap that applies a uniform sealant shroud to fasteners, allowing for efficient and consistent sealant application.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If manual brush application of sealant is used, then flexibility and adaptability to irregular surfaces are maintained, but labor intensity increases and quality consistency deteriorates

Engineering Contradiction:
ImproveflexibilityVSAvoidlabor intensity
Core Design Contradiction:
Ease of operationVSProductivity

Solution Approach 1:

The sealant application system is designed to apply sealant automatically without requiring manual brush manipulation. The cap rotates automatically or is driven by a mechanism that distributes sealant uniformly around the fastener, allowing the system to serve itself rather than requiring continuous human intervention while maintaining adaptability to irregular surfaces.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The manual brush mechanical system is replaced with an automated sealant delivery mechanism. Instead of using a brush that requires manual control, the invention uses a controlled delivery system that can automatically apply and distribute sealant, replacing the need for manual mechanical brush application while improving productivity and consistency.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

2Adaptability or versatility

If manual brush sealing is used, then ability to handle irregular surfaces is maintained, but quality control becomes difficult and rework increases

Engineering Contradiction:
Improveability to handle irregular surfacesVSAvoidquality consistency
Core Design Contradiction:
Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The system incorporates feedback mechanisms to monitor and control sealant application quality. Sensors or detection systems can verify proper sealant distribution and coverage, providing feedback that allows for real-time adjustments to maintain consistent quality across all fasteners, eliminating the quality control difficulties associated with manual brush application.

Inventive Principle:
Principle #23Feedback

Solution Approach 2:

The invention controls sealant application parameters such as flow rate, pressure, and distribution pattern to ensure consistent quality. By precisely controlling these parameters, the system can maintain uniform sealant application even on irregular surfaces, significantly improving manufacturing precision compared to manual brush methods where parameter control is difficult.

Inventive Principle:
Principle #35Parameter changes

3Extent of automation

If non-brush applicators are used, then some automation is introduced, but operator skill dependency remains and method consistency deteriorates

Engineering Contradiction:
Improveautomation levelVSAvoidoperator skill dependency
Core Design Contradiction:
Extent of automationVSEase of operation

Solution Approach 1:

The sealant application system is designed to apply sealant automatically without requiring manual brush manipulation. The cap rotates automatically or is driven by a mechanism that distributes sealant uniformly around the fastener, allowing the system to serve itself rather than requiring continuous human intervention while maintaining adaptability to irregular surfaces.

Inventive Principle:
Principle #25Self-service

4Manufacturing precision

If vacuum-forming process is used to create fitted cap, then manufacturing precision and uniformity are improved, but process complexity increases

Engineering Contradiction:
Improvecap uniformityVSAvoidprocess complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The vacuum-forming process creates a precise copy or replica of the fastener's geometry. By using the fastener itself or a template as a mold, the system automatically generates a cap that perfectly matches the fastener's shape and dimensions, achieving high manufacturing precision without requiring complex manual measurement and fabrication processes.

Inventive Principle:
Principle #26Copying

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

Facilitates continuous and uniform sealant application, reducing labor and improving quality by enabling efficient distribution of sealant around fasteners with a rotatable cap-manipulation tool, preventing air bubbles and imperfections.

Implementation Method 1

heating a first polymer sheet to a specified temperature

Methodology Applied
Scientific EffectHeating: Heating

Implementation Method 2

applying suction to the first polymer sheet, positioned a predetermined distance from the first side of the support plate and heated to the specified temperature by the first means, through the first plurality of through-openings from the second side of the support plate to vacuum-form the first polymer sheet over the precursor cap

Methodology Applied
Scientific EffectVacuum: Vacuum

Data Source

PatentEP3501792B1Systems and methods for making and using a fitted cap for applying a shaped sealant shroud to a portion of a fastener
Publication Date: 2021.09.01 THE BOEING CO
  • EP3501792B1 patent drawingFigure 1
  • EP3501792B1 patent drawingFigure 2
  • EP3501792B1 patent drawingFigure 3

AI summary

A system (200) for making a fitted cap (300) comprises a fastener template (202), dimensionally identical to a portion (106) of a fastener (100) and extending from a support plate (210), and a first plurality of through-openings (212) penetrating the support plate (210) and arranged about the fastener template (202). The system (200) also comprises a precursor cap (320) that is geometrically complementary to the fastener template (202), first means (217) for heating a first polymer sheet (270), and second means (219) for applying suction to the first polymer sheet (270) through the first plurality of through-openings (212) to vacuum-form the first polymer sheet (270) over the precursor cap (320). After vacuum-forming the first polymer sheet (270) over the precursor cap (320), at least a portion of the first polymer sheet (270) forms the fitted cap (300). The fitted cap (300) is configured to apply a shaped sealant shroud (590) to the portion (106) of the fastener (100).