Aircraft Nacelle Pantograph Hinge Lateral Separation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Interactions between two fan cowls in an aircraft propulsion system occur when they are opened simultaneously, leading to operational inefficiencies and potential damage.
Innovation Solution
The implementation of an articulation system with two pantograph hinges and a locking mechanism for each fan cowl, allowing independent movement and locking, preventing interactions and reducing weight compared to traditional hinges.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional hinges are used to articulate fan cowls, then the structure is simple, but interactions occur between the two fan cowls when opened simultaneously
Solution Approach 1:
The articulation system is segmented into two independent pantograph mechanisms, one for each fan cowl. Each pantograph consists of multiple articulated links (first arm, second arm, connecting arm) that work independently to control the movement of each fan cowl, preventing interactions between the two cowls during opening operations
Solution Approach 2:
The pantograph hinges provide dynamic control over the fan cowl opening motion. The articulated links and elbows create a dynamic mechanism that automatically separates the fan cowls laterally as they open, transforming the opening motion from a potential collision course into a controlled separation trajectory
2Weight of moving object
If traditional hinges are used for fan cowl articulation, then the structure is simple, but weight is not optimized
Solution Approach 1:
The articulation system uses two separate pantograph hinges instead of a single complex hinge mechanism. Each pantograph is composed of multiple lighter articulated links (first arm, second arm, connecting arm) that can be manufactured from lighter materials while providing the necessary structural support and movement control
Solution Approach 2:
The pantograph mechanism introduces an additional dimension of movement control by using articulated elbows and connecting arms. This multi-link arrangement allows the fan cowl to move away laterally as it opens, creating a three-dimensional movement path that reduces the need for heavy counterbalancing mechanisms
3Ease of operation
If fan cowls are opened simultaneously, then maintenance access is achieved, but interactions occur between the cowls
Solution Approach 1:
The pantograph hinge mechanism performs preliminary separation action as the fan cowl begins to open. The articulated links are configured so that the fan cowl automatically moves away laterally from its closed position before full opening is achieved, preventing interactions with the other fan cowl before they can occur
Solution Approach 2:
The pantograph mechanism acts as an intermediary between the locking means and the fan cowl movement. It translates the simple locking/unlocking action into a controlled separation motion, mediating the interaction between the two fan cowls and enabling simultaneous opening without collision
Data Source
AI summary
A propulsion system having a chassis, two fan cowls and, for each one, an articulation system fastened between the chassis and the fan cowl, so as to move the fan cowl between a closed position and an open position and a locking device like a clamping screw, wherein each articulation system has, for each fan cowl, two pantograph hinges. With such an arrangement, each fan cowl moves away laterally as soon as its opening starts.