Aircraft Legrest Assembly Using Nested Segments and Gas Springs
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing legrest assemblies for aircraft passenger seats fail to provide adequate support for all portions of a passenger's legs and feet while maintaining a compact configuration, particularly in densely seated sections where space is limited.
Innovation Solution
A deployable legrest assembly utilizing tensioned fabric diaphragms and a combination of hinging mechanisms, gas spring cylinders, and armrest-mounted controls allows for the deployment and stowage of the legrest without the need for motors or powered actuators, enabling adjustable support for calves, ankles, and feet.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a legrest assembly provides support for all portions of a passenger's legs and feet, then passenger comfort is improved, but the space required for the legrest increases
Solution Approach 1:
The legrest assembly is divided into multiple segments: a calf support portion and a foot support portion. The calf support includes a calf support diaphragm attached to a calf support frame, while the foot support includes a foot support diaphragm attached to a foot support frame. This segmentation allows each portion to be optimized independently for both comfort and compactness.
Solution Approach 2:
The foot support frame is positioned within the calf support frame when retracted, creating a nested configuration. The foot support diaphragm can be stored within the calf support diaphragm assembly. This nesting arrangement minimizes the overall volume occupied by the legrest when not in use, while still providing full leg and foot support when deployed.
2Volume of moving object
If a legrest assembly is designed to be compact for space constraints, then space utilization is improved, but the ability to support all portions of legs and feet deteriorates
Solution Approach 1:
The legrest assembly transitions between two dynamic states: a retracted state where the foot support frame is positioned within the calf support frame for compact storage, and an extended state where the foot support frame extends beyond the calf support frame to provide full foot and leg support. This dynamic reconfiguration allows the assembly to adapt between compactness and full functionality.
3Ease of operation
If powered actuators are used to deploy and stow the legrest, then ease of operation is improved, but device complexity and cost increase
Solution Approach 1:
The legrest assembly utilizes the passenger's own body weight and leg movement to automatically deploy and stow the mechanism. When the passenger places their legs on the calf support and extends them, the weight and motion automatically trigger the deployment sequence. Conversely, when the passenger retracts their legs, the mechanism automatically stows. This eliminates the need for motors, sensors, or complex control systems.
Solution Approach 2:
A weight-sensitive switch acts as an intermediary between the passenger's legs and the actuation system. The switch detects when the passenger's legs are placed on the calf support and automatically activates the motor to deploy the legrest. The switch also detects when legs are removed and triggers the stowage sequence. This simple intermediary device provides automated operation without requiring complex control systems.
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 comfortable and adjustable legrest support that can be easily deployed and stowed, optimizing space usage in aircraft seats without the need for complex actuation systems, enhancing passenger comfort within space and financial constraints.
Implementation Method 1
a gas spring cylinder that assists in deploying and stowing the calf support
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A legrest assembly including a calf support hinged to a forward end of a seat frame and moveable between a stowed configuration generally vertically disposed below the forward end of the frame and a deployed configuration inclined above the stowed configuration, a foot support movable with and telescopically connected to the calf support, and a foot rest pivotally connected to the foot support and pivotable between a stowed configuration substantially parallel to the foot support and a deployed configuration extending outward from the foot support.