Electro Hydrostatic Actuator Redundancy via Shared Hydraulic Supply
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing electro hydrostatic actuator (EHA) systems for aircraft landing gear retraction/extension mechanisms require multiple hydraulic pumps and electric motors, leading to increased space occupation and weight due to the need for redundancy, which complicates the system's design and maintenance.
Innovation Solution
The EHA system is configured with a plurality of hydraulic actuators that receive operation oil sequentially, and a corresponding number of hydraulic supply sources are provided in parallel to ensure redundancy, allowing for efficient operation with reduced size and weight by sharing oil supply capacity during normal operation and compensating for failed sources.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If multiple hydraulic pumps and electric motors are provided for each hydraulic actuator to ensure redundancy, then the reliability of the EHA system is improved, but the weight of the system increases significantly
Solution Approach 1:
The patent merges multiple hydraulic supply sources into a shared common hydraulic line system. Instead of providing separate hydraulic pumps and motors for each actuator, the invention combines them into common supply sources that serve multiple actuators sequentially, reducing the total number of components while maintaining redundancy through the shared system architecture.
Solution Approach 2:
The common hydraulic supply sources are designed to serve multiple different hydraulic actuators (gear actuator, door actuator, down-lock release actuator) through a shared hydraulic line. This multi-functional approach allows a single hydraulic pump and motor to perform the work of multiple dedicated units, reducing overall system weight while maintaining the ability to operate any individual actuator.
2Reliability
If multiple hydraulic pumps and electric motors are provided for each hydraulic actuator to ensure redundancy, then the reliability of the EHA system is improved, but the space occupied by the EHA system expands
Solution Approach 1:
The patent merges multiple hydraulic supply sources into a shared common hydraulic line system. Instead of providing separate hydraulic pumps and motors for each actuator, the invention combines them into common supply sources that serve multiple actuators sequentially, reducing the total number of components while maintaining redundancy through the shared system architecture.
Solution Approach 2:
The common hydraulic supply sources are designed to serve multiple different hydraulic actuators (gear actuator, door actuator, down-lock release actuator) through a shared hydraulic line. This multi-functional approach allows a single hydraulic pump and motor to perform the work of multiple dedicated units, reducing overall system volume while maintaining the ability to operate any individual actuator.
3Weight of moving object
If a single hydraulic supply source supplies operation oil to multiple hydraulic actuators, then the weight and space of the EHA system are reduced, but the reliability is compromised without redundancy
Solution Approach 1:
The patent implements a dynamic control system that can switch between normal dual-source operation and emergency single-source operation. The controller dynamically adjusts the hydraulic line configuration based on system state, allowing the common hydraulic supply sources to provide redundancy during normal operation while maintaining weight efficiency, and automatically adapting when failure occurs to ensure continued operation.
Solution Approach 2:
The system is designed with beforehand cushioning by providing multiple common hydraulic supply sources that can compensate for each other's failure. The redundant capacity is built into the common supply system architecture, so when one hydraulic pump or motor fails, the other can immediately take over without compromising the ability to operate all hydraulic actuators.
4Reliability
If multiple hydraulic supply sources are provided in parallel to supply operation oil sequentially to each hydraulic actuator, then redundancy is ensured with minimum space and reduced weight
Solution Approach 1:
The patent segments the hydraulic supply function into separate common hydraulic supply sources (each with its own pump and motor) that share a common hydraulic line. This segmentation allows independent operation and failure isolation of each supply source while maintaining system-level redundancy, reducing the complexity of controlling individual actuators compared to a fully distributed system.
Solution Approach 2:
The common hydraulic line acts as an intermediary that connects multiple hydraulic actuators to multiple common hydraulic supply sources. This intermediary structure simplifies the system architecture by providing a shared communication and fluid transport medium, reducing the complexity of individual connections while maintaining the ability to isolate and control failures in specific segments.
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
This configuration ensures redundancy while minimizing the EHA system's size and weight, allowing for effective landing gear retraction/extension with reduced operational complexity and improved reliability.
Implementation Method 1
a plurality of hydraulic supply sources provided in parallel to each other so that operation oil is supplied to each hydraulic actuator
Implementation Method 2
each hydraulic supply source includes a single hydraulic pump configured to discharge the operation oil
Implementation Method 3
each hydraulic supply source includes a single electric motor configured to drive the hydraulic pump
Data Source
Figure 1
Figure 2
Figure 3
AI summary
An electro hydrostatic actuator system for retracting/extending a landing gear includes a plurality of hydraulic actuators and a plurality of hydraulic supply sources each including a single hydraulic pump and a single electric motor and provided in parallel to each other. In a normal state, the hydraulic supply sources together supply operation oil sequentially to the hydraulic actuators. When any of the hydraulic supply sources is failed, the other hydraulic supply source(s) other than the failed hydraulic supply source supplies operation oil sequentially to the hydraulic actuators.