Aircraft Door Deflection Limiter Using Pressure Differential
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Modern aircraft face challenges in limiting door deflection due to pressure differences, which increases aerodynamic resistance and fuel consumption, and existing deflection limiters are complex and heavy, requiring integration with the door locking system.
Innovation Solution
A pressure-controlled deflection limiter that automatically engages holding elements with abutments at the door jamb or edge, allowing for independent operation from the normal locking system, featuring a piston and spring mechanism or an elastic membrane, to limit door deflection effectively without adding weight or complexity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a complex mechanical lever arrangement is used to transform movement sequences in the door locking system, then the deflection limiter can be integrated with the locking system, but the device becomes heavy and structurally complex
Solution Approach 1:
The invention extracts the deflection limitation function from the door locking system, allowing it to operate independently. The holding element and abutment mechanism work autonomously based on pressure differential, eliminating the need for complex mechanical linkages to the locking system while maintaining effective deflection control.
Solution Approach 2:
The invention replaces complex mechanical lever arrangements with a pressure-differential-based mechanism. The holding element is actuated directly by the pressure difference between internal and external air pressure, eliminating the need for mechanical transformation of movement sequences and reducing structural complexity.
2Reliability
If deflection limiters are coupled with the door locking system, then they can provide secure locking, but they increase the weight and complexity of the overall system
Solution Approach 1:
The deflection limiter operates autonomously using the pressure differential between internal and external air pressure to actuate the holding element. This self-service mechanism eliminates the need for additional actuators, motors, or complex control systems, thereby reducing weight while maintaining reliable deflection control.
Solution Approach 2:
The invention uses pneumatic pressure differential to actuate the holding element directly. The pressure difference between internal and external air pressure provides the actuating force, eliminating the need for heavy mechanical actuators and reducing overall system weight while maintaining effective operation.
3Stability of the object's composition
If pins are moved into recesses through complex mechanical arrangements, then deflection can be limited, but the structure becomes heavy and complicated
Solution Approach 1:
The invention extracts the deflection control function from the door locking system, allowing it to operate independently. The holding element and abutment mechanism work autonomously based on pressure differential, eliminating the need for complex mechanical linkages to the locking system while maintaining effective deflection control.
Solution Approach 2:
The invention replaces complex mechanical lever arrangements with a pressure-differential-based mechanism. The holding element is actuated directly by the pressure difference between internal and external air pressure, eliminating the need for mechanical transformation of movement sequences and reducing structural complexity.
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 provides a weight-saving, reliable, and automatic deflection limitation that reduces aerodynamic resistance and fuel consumption by effectively managing door deflection across varying altitudes, while allowing normal operation near ground level.
Implementation Method 1
The lever 35, which has a hook 37 at its end, can be brought into engagement with an abutment 31 by means of an elastic membrane 39 which is subjected on one side to the pressure difference Δp between an internal pressure pi existing within the fuselage cell 3 and an outside pressure pa prevailing outside of the fuselage cell
Implementation Method 2
the lever 35, which has a hook 37 at its end, can be brought into engagement with an abutment 31 by means of an elastic membrane 39
Data Source
AI summary
The invention relates to a device for limiting the deflection of a door (1), particularly a hatch or a freight door, arranged in a fuselage cell (3) of an aircraft, having at least one holding element (5) arranged preferably in the region of a door jamb (4) or in the region of a door leaf edge (7).In order to ensure deflection limitation for doors, hatches and freight doors in aircraft which can be triggered manually independently of an actuation of the normal locking system, it is proposed according to the invention that the at least one holding element (5) can, if there is a sufficient pressure difference Δp between the internal pressure pi prevailing in the fuselage cell (3) and the outside air pressure pa prevailing outside of the fuselage cell (3), be brought into engagement with at least one abutment (6) arranged in the region of the door leaf edge (7) or the door jamb (4).In addition it is proposed that if there is a sufficiently large pressure difference Δp the at least one holding element (30, 55) is automatically pivoted or can be manually pivoted and can hereby be brought into engagement with the at least one abutment (31, 52).