Aircraft Door Locking Pin Mechanism Against Vibration Unlocking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional aircraft door latches are prone to unintentional unlocking due to vibration during flight, posing a safety risk.
Innovation Solution
A locking system with a movable locking pin that prevents rotation of the door gear axis, requiring intentional operation of either the interior or exterior handle to unlock the door, thereby preventing disengagement due to vibration.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a conventional aircraft door latch is used, then the door can be opened from both inside and outside, but the latch is prone to unintentional unlocking due to vibration during flight
Solution Approach 1:
The locking pin is positioned to preemptively block the door gear axis before vibration can cause unintentional rotation. The pin creates a preliminary mechanical constraint that counteracts the harmful vibrational forces, preventing the latch from disengaging due to aircraft vibration during flight.
Solution Approach 2:
The locking mechanism is segmented into independent components: the locking pin, door gear axis, interior handle, and exterior handle. This segmentation allows the locking pin to function independently as a vibration prevention element while the handles provide independent unlocking capability from inside or outside the aircraft.
2Reliability
If a locking pin is added to prevent vibration-induced unlocking, then locking reliability improves, but the device complexity increases
Solution Approach 1:
The locking pin is merged with the existing door gear axis structure, extending from it into the chamber. This integration allows the locking pin to function as both a structural extension of the gear axis and a independent vibration prevention element, adding reliability without proportionally increasing overall mechanism complexity.
Solution Approach 2:
The locking pin serves multiple functions: it blocks the door gear axis to prevent vibration-induced unlocking, and it can be independently actuated by either the interior or exterior handle to unlock the door. This multi-functionality adds reliability while minimizing the increase in device complexity.
3Reliability
If the locking pin is made independently operable from both handles, then safety is enhanced, but the ease of operation decreases
Solution Approach 1:
The locking pin is designed with dynamic positioning capability, allowing it to move between a blocking position (preventing unintentional unlocking) and an retracted position (allowing intentional unlocking). This dynamic behavior enables the system to automatically adapt between safety mode during flight and operational mode when unlocking is required.
Data Source
AI summary
A locking system for an aircraft door having a door handle housing to mount to the aircraft door; a locking mechanism supported by the door handle housing; an exterior handle and an interior handle each to manipulate the locking mechanism. The locking mechanism having a door gear axis to rotate via operation of the interior handle and the exterior handle to lock and unlock the locking mechanism; and a locking pin extending from the door gear axis and into a chamber of the door handle housing, the locking pin having a first position and a second position, the first position of the locking pin blocks rotation of the door gear axis and the second position of the locking pin allows rotation of the door gear axis. The locking pin is moveable from the first position to the second position via operation of the interior handle and the exterior handle.