Nose Landing Gear Actuator Pump With Local Hydraulic Recirculation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Aircraft landing gear systems face inefficiencies due to centralized hydraulic systems, which require large volumes of hydraulic fluid, leading to weight penalties and labor-intensive leak repairs, and electromechanical actuators struggle with over-running loads and jamming failures.
Innovation Solution
An electric nose landing gear system featuring an electric motor, hydraulic pump, gearbox, clutch, and accumulator, with a recirculation hydraulic circuit and directional control valve, allowing for efficient hydraulic fluid circulation and clutch engagement/disengagement to power the steering collar and actuators, reducing the need for hydraulic pressure and enhancing reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If centralized hydraulic systems are used, then hydraulic power can be provided to landing gear actuators, but the system requires large volumes of hydraulic fluid leading to increased weight
Solution Approach 1:
The patent divides the centralized hydraulic system into distributed local hydraulic systems at each landing gear assembly. Each local system has its own hydraulic pump and actuators, eliminating the need for long hydraulic tubing networks and large fluid volumes throughout the aircraft. This segmentation provides the necessary hydraulic power locally while dramatically reducing the total weight of hydraulic fluid required.
Solution Approach 2:
The patent implements local hydraulic power generation at each landing gear assembly through electric motor-driven pumps. This local quality approach allows each landing gear to have its own independent hydraulic system, providing power where needed without requiring the entire aircraft to carry sufficient hydraulic fluid for all systems simultaneously, thereby reducing overall weight.
2Power
If centralized hydraulic systems with long tubing networks are used, then hydraulic fluid can be transported to the nose region, but the system develops leaks requiring labor intensive repairs
Solution Approach 1:
By segmenting the hydraulic system into isolated local circuits at each landing gear assembly, the patent eliminates the long continuous tubing networks that are prone to leaks. Each local system is self-contained with minimal tubing, reducing the surface area and potential leak points while maintaining the necessary hydraulic fluid flow for actuator operation.
Solution Approach 2:
The patent extracts the hydraulic pump function from the centralized aft location and places it locally at each landing gear assembly. This extraction eliminates the need for long supply and return tubing networks, removing the majority of potential leak points while preserving the hydraulic power delivery capability.
3Power
If centralized hydraulic systems are used, then landing gear actuators can be powered, but the system requires oversized components to provide large pressurized flow rates
Solution Approach 1:
The patent segments the hydraulic power requirement so that each local system only needs to provide sufficient flow rate for its specific landing gear actuators, not for all landing gear systems simultaneously. This allows for much smaller, more appropriately sized hydraulic pumps and components at each location, reducing overall device complexity while maintaining the required pressurized flow rates for actuator operation.
4Device complexity
If electromechanical actuators are used, then hydraulic components can be reduced, but the system struggles with over-running loads and jamming failures
Solution Approach 1:
The patent merges the advantages of both hydraulic and electromechanical systems by using electric motor-driven hydraulic pumps locally. This combination allows the system to use electromechanical actuators for steering and control while maintaining hydraulic actuators for retraction and extension, where hydraulic systems provide superior handling of over-running loads and resistance to jamming failures.
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 reduces weight and maintenance needs by localizing hydraulic power generation and using an electrically actuated clutch, improving the handling of over-running loads and addressing jamming failures, while maintaining efficient operation of the nose landing gear.
Implementation Method 1
the accumulator is configured to store hydraulic fluid at a specified pressure that is sufficient to engage or disengage the clutch
Implementation Method 2
An electromechanical actuator pump includes an electric motor; a hydraulic pump connected to the electric motor
Data Source
AI summary
A nose landing gear system is disclosed. In various embodiments, the nose landing gear system includes an electric motor; a hydraulic pump connected to the electric motor; a gearbox connected to the electric motor; and a clutch configured to mechanically couple the gearbox to a steering collar.