Aircraft Fan Cowl Latching System with Gripping Arm
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional latching systems for aircraft fan cowl doors can incorrectly indicate that the doors are secured when they are not, due to the handle being able to move to the closed position even if the doors are not properly secured, making it difficult to verify if the cowl doors are fully closed and secured before flight, especially with larger engines that reduce ground clearance.
Innovation Solution
A latching system with a gripping arm and biasing element that ensures the handle can only be fully closed when the gripping arm is securely coupled to the anchor, preventing misalignment of apertures and requiring a nominal clamping force for proper closure, and includes an actuating member to lock the handle in the closed position, ensuring visual confirmation of secure closure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the handle is allowed to move freely to the closed position, then the ease of operation is improved, but the reliability of the visual indication is worsened because the handle may indicate closed position even when the doors are not properly secured
Solution Approach 1:
The patent requires the gripping arm to be properly engaged with the anchor before the handle can reach the closed position. This preliminary engagement condition ensures that the doors are securely latched before the visual indication (handle position) shows closure, resolving the contradiction between ease of operation and reliability of indication.
Solution Approach 2:
The gripping arm acts as an intermediary mechanical element between the handle and the anchor. It transmits the closing force from the handle to the anchor while providing a physical constraint that prevents the handle from reaching the closed position unless the gripping arm is properly engaged, thus ensuring reliable visual indication.
2Productivity
If the cowl doors are positioned low due to large engine diameter, then the productivity of engine installation is improved, but the ease of detecting and measuring the latching status is worsened because visual verification becomes difficult
Solution Approach 1:
The patent utilizes the position and orientation of the handle as a visual indicator system. When the handle is in the closed position, it provides a clear visual signal that the latching is complete, allowing operators to verify latching status from a distance without needing to physically inspect the gripping arm engagement, thus solving the visibility problem.
3Ease of operation
If the handle can move to closed position without proper gripping arm engagement, then the ease of operation is improved, but the safety is worsened because unsecured doors may be ejected during flight
Solution Approach 1:
The patent ensures that proper gripping arm engagement with the anchor occurs before the handle can reach the closed position. This preliminary engagement condition guarantees that the doors are securely latched before the operator can visually confirm closure, preventing door ejection while maintaining simple operation.
Solution Approach 2:
The mechanical linkage between the gripping arm and handle provides immediate feedback to the operator. The handle can only reach the closed position when the gripping arm is properly engaged, providing real-time feedback that confirms secure latching has occurred, thus preventing unsafe closure.
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 system ensures that the cowl doors are properly secured and locked during flight, providing a clear visual indication of the latching status and facilitating easier maintenance operations without damaging components.
Implementation Method 1
a biasing element for biasing the gripping arm. In some embodiments the biasing element biases the gripping arm to a position in which the gripping arm of the latch is unsecured to the anchor
Data Source
AI summary
A latching system for selectively securing together two components, such as the fan cowl doors of a nacelle of an aircraft, closed. The latching system generally includes an anchor and a latch. The latch has a handle movable from an open and a closed position. The handle is precluded from reaching the closed position unless the anchor and latch are secured. Also, the positioning of a keeper portion of the anchor may be adjustable.