Angled 3D Printed Composite Fittings for Stronger Tube Joints
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing composite tube fittings for aircraft and spacecraft are heavy due to being machined from titanium, and 3D printing at 0 degrees results in insufficient torsional, axial, and horizontal strengths without support structures, leading to waste and post-processing requirements.
Innovation Solution
3D printing composite tube fittings at an angle between 10 and 65 degrees, with a complementary chamfered surface, and incorporating an internally threaded insert to enhance structural integrity and reduce weight.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If fittings are machined from titanium, then strength and structural integrity are achieved, but weight increases significantly
Solution Approach 1:
The patent changes the manufacturing method from traditional machining to 3D printing, and alters the material composition by incorporating continuous fibers (carbon, Kevlar, or fiberglass) into the polymer matrix. This composite approach maintains structural integrity while significantly reducing weight compared to solid titanium fittings.
Solution Approach 2:
The fitting is constructed as a composite material system combining polymer matrix (nylon or onyx) with continuous reinforcement fibers (carbon fiber, Kevlar, or fiberglass). This composite structure achieves the required strength-to-weight ratio by leveraging the high tensile strength of fibers while maintaining the formability and light weight of polymer materials.
2Ease of manufacture
If 3D printing is performed at 0 degrees, then manufacturing simplicity is maintained, but torsional, axial, and horizontal strengths become insufficient
Solution Approach 1:
The patent introduces a new dimensional parameter - the print angle - to optimize mechanical properties. By printing at angles between 10-65 degrees rather than 0 degrees, the layers are oriented to better resist torsional, axial, and horizontal loads. This angular orientation distributes stress more effectively across the layered structure.
Solution Approach 2:
The patent applies different print angles to different regions or orientations of the fitting to optimize local mechanical properties. The complementary chamfered surface geometry is specifically designed to work with the angled printing approach, creating localized stress distribution patterns that enhance overall structural integrity.
3Reliability
If support structures are used during 3D printing, then structural integrity during printing is maintained, but waste increases and post-processing requirements arise
Solution Approach 1:
By changing the print angle to 10-65 degrees, the patent inherently provides self-supporting geometry during the printing process. The angled layer deposition creates a structure that supports itself without requiring additional support materials, eliminating waste and reducing post-processing needs while maintaining structural integrity.
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 angled 3D printed fittings achieve improved torsional, axial, and horizontal strengths while minimizing waste and reducing weight, with axial strengths of at least 9000 lbf, and composite tube assemblies achieving at least 300 lbf.
Implementation Method 1
the body is 3D printed by laying successive horizontal layers of material with the first axis at an angle between 10 degrees and 65 degrees from a vertical axis (i.e., a print angle)
Implementation Method 2
the material is at least one of an onyx, plastic, or nylon reinforced with a continuous fiber
Data Source
Figure 1
Figure 2~5
Figure 3~4
AI summary
A 3D printed fitting includes an axially extending body having a first end opposite a second end. The body extends along a first axis, and the body is 3D printed by laying horizontal successive horizontal layers of material with the first axis at a print angle between 0 degrees and 65 degrees from a vertical axis.