Aircraft Flap Hinge Arrangement Reducing Constraint Forces
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional flap arrangements in aircraft experience significant constraint forces due to elastic deformation under external loads, leading to stress and load distribution issues, which can result in structural damage and weight inefficiencies.
Innovation Solution
A flap arrangement with a hinge system featuring at least three spaced bearing points, where two points are rigidly connected to the basic body and flap, and the remaining points allow local movement perpendicular to the hinge line, reducing constraint forces and stress by providing additional degrees of freedom.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a hinge arrangement with more than two bearing points is used for slender and long flaps, then the flap can be securely attached to the basic body, but constraint forces occur due to static over-determination when the basic body undergoes elastic deformation
Solution Approach 1:
The hinge arrangement is segmented into rigid bearing points (providing secure attachment) and non-rigid bearing points (allowing movement). This segmentation divides the function of the hinge arrangement into force transmission and deformation accommodation, resolving the contradiction between secure attachment and constraint force reduction.
Solution Approach 2:
The hinge arrangement transitions from a completely rigid system to a dynamic system where non-rigid bearing points can move relative to each other. This dynamic capability allows the system to adapt to elastic deformations of the basic body, preventing the buildup of constraint forces while maintaining secure attachment through rigid bearing points.
2Stability of the object's composition
If the basic body is considered as a clamped carrier, then it provides stable support, but attaching a movable flap creates static over-determination leading to constraint forces under load
Solution Approach 1:
Different bearing points have different local qualities: rigid bearing points provide stable support and force transmission, while non-rigid bearing points provide movement freedom. This local differentiation allows the system to maintain overall stability while locally accommodating deformations to prevent constraint forces.
3Ease of operation
If the flap assumes a deflected position relative to the basic body under load, then it performs its control function, but significant constraint forces occur due to the need to adapt to the basic body's bending line
Solution Approach 1:
The non-rigid bearing points provide dynamic adaptability that allows the flap to deflect freely while the rigid bearing points maintain the necessary structural connection. This dynamic capability eliminates constraint forces during flap operation.
Data Source
AI summary
A flap arrangement includes a basic body, a hinge arrangement, and a flap that by the hinge arrangement is movably held on the basic body. The hinge arrangement includes at least three bearing points spaced apart from each other and arranged on a shared hinge line, wherein two bearing points are rigidly connected to the basic body and to the flap, and wherein the remaining bearing points in each case allow local movement between the basic body and the flap in at least one first spatial direction perpendicularly to the hinge line. Thus, load-induced constraint forces between the basic body and the control surface can be prevented.