Laminated Aircraft Window Structure for Lower Weight and Equal Rigidity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Aircraft cabin windows composed of bi-stretched poly(methyl methacrylate) (PMMA) sheets face challenges in balancing mechanical resistance and weight, with the inner pane's design primarily focused on mechanical resistance rather than differential pressure resistance, leading to potential dislodgment risks.
Innovation Solution
Replace the PMMA interior slab with a thin laminated glass slab and the outer PMMA slab with a thinned PMMA sheet laminated with glass, using a glass thickness of 0.1 to 3 mm and a structural polymer thickness of 3 to 100 mm, bonded by adhesive layers, to maintain mechanical properties while reducing weight.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the inner pane is made of thick PMMA to ensure mechanical resistance, then the mechanical strength is improved, but the weight increases
Solution Approach 1:
The patent applies composite materials by combining glass sheets with adhesive layers to create a laminated structure that provides equivalent mechanical resistance to PMMA while reducing weight. The glass/adhesive composite achieves the required strength-to-weight ratio improvement.
2Strength
If the outer pane is made of thick PMMA to ensure differential pressure resistance, then the pressure resistance is improved, but the weight increases
Solution Approach 1:
The outer pane uses a composite structure of glass sheets bonded with adhesive layers, replacing thick PMMA. This composite achieves equivalent differential pressure resistance with reduced weight, as glass provides high strength-to-weight ratio for pressure containment.
3Weight of moving object
If glass is used to replace PMMA for weight reduction, then the weight is reduced, but the manufacturing complexity increases
Solution Approach 1:
The window panes are segmented into multiple thin glass sheets (0.1-3mm each) bonded by adhesive layers. This segmentation allows each component to be manufactured separately and assembled, reducing overall manufacturing complexity compared to forming large thick PMMA pieces.
Solution Approach 2:
The use of standard glass sheets with adhesive bonding creates a modular composite structure that simplifies manufacturing compared to custom-molded thick PMMA, as glass sheets are commercially available in standard thicknesses and can be bonded using conventional adhesive processes.
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 achieves lighter aircraft windows with equivalent stiffness, offering improved mechanical resistance and reduced weight, while incorporating additional features like thermal control, electromagnetic shielding, and anti-fogging properties.
Implementation Method 1
bonded by adhesive layers
Data Source
Figure 1~2
Figure 3~4
Figure 5~6
AI summary
The invention relates to an aircraft window consisting of an inner panel (1) and an outer panel (2) which are separated by a layer of air (3) and by an installation seal (4) into which a peripheral portion of the window is set, the inner panel (1) consisting of a first, outer pane of glass (11) and a second, inner pane of glass (12), each having a thickness from 0.1 mm to 3 mm and being bonded to one another by a first adhesive interlayer (13) with a thickness from 50 µm to 2 mm, and/or the outer panel (2) consisting of a first, outer sheet of transparent structural polymer material (21) with a thickness from 1.5 mm to 100 mm bonded to a third, inner pane of glass (22) with a thickness from 0.1 mm to 30 mm by means of a second adhesive interlayer (23) with a thickness from 50 µm to 2 mm.