Electromechanical Brake Actuator Parking Lock Without Continuous Power
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing aircraft wheel braking systems face high electricity consumption and reliability issues due to continuous power requirements for fail-safe parking brakes, leading to overheating and premature wear of components.
Innovation Solution
A motor sub-assembly for an electromechanical brake actuator featuring a selector mechanism with a shuttle that can be locked in place without electrical energy, using a combination of teeth and a permanent magnet to maintain the brake engaged, reducing energy consumption and enhancing reliability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a fail-safe parking brake is used to lock the shaft when not powered, then safety is improved, but electricity consumption increases and the coil gets hot
Solution Approach 1:
The patent applies periodic action by using a coil that is only activated temporarily to move the shuttle between positions, rather than requiring continuous power. The permanent magnet provides sustained holding force without energy consumption, creating an on-demand rather than continuous operation pattern that reduces overall electricity usage while maintaining safety.
Solution Approach 2:
The patent replaces the traditional continuously-powered electromagnetic braking system with a hybrid system that uses a permanent magnet for the primary holding function. This substitution eliminates the need for continuous electrical energy to maintain the braking state, significantly reducing electricity consumption and heat generation while preserving the fail-safe capability.
2Reliability
If the parking brake is powered continuously during operation, then the brake remains engaged, but electricity consumption increases and the coil overheats
Solution Approach 1:
The coil is activated only periodically to transition the shuttle between engaged and disengaged positions, rather than operating continuously. This intermittent operation dramatically reduces thermal accumulation in the coil, preventing overheating while maintaining reliable brake engagement when required.
Solution Approach 2:
The permanent magnet replaces the coil as the primary force-generating element for maintaining brake engagement. Since permanent magnets produce magnetic fields without energy input or heat generation, this substitution eliminates the overheating problem entirely while ensuring continuous reliable brake engagement.
3Force
If a traditional friction brake device is used, then braking force is achieved, but sealed compartments are required which increases manufacturing complexity
Solution Approach 1:
The patent replaces the friction-based braking mechanism with a magnetic coupling system. The magnetic brake exerts force through magnetic attraction between the rotor and stator without physical contact, eliminating the need for sealed compartments to protect friction surfaces from lubrication. This substitution maintains effective braking force while dramatically simplifying manufacturing by removing sealing requirements.
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 allows for reduced electricity consumption and improved reliability by maintaining the brake engaged without continuous power, reducing wear and manufacturing costs, and enabling the actuator to function in lubricated environments without sealed compartments.
Implementation Method 1
using a combination of teeth and a permanent magnet to maintain the brake engaged
Data Source
AI summary
A motor sub-assembly for an electromechanical brake actuator of an aircraft wheel includes a casing, a shaft mounted in the casing, and an electric motor mounted in the casing rotate the shaft, the shaft having an end connected to a screw-and-nut assembly to exert a force on a stack of disks for braking the aircraft wheel. The shaft has a first set of teeth and the motor sub-assembly has a shuttle mounted to slide relative to the casing and provided with a second set of teeth. The motor sub-assembly includes a selector mechanism that moves the shuttle selectively between first and second positions in which the first set of teeth is engaged and disengaged with the second set of teeth, respectively. The motor sub-assembly includes a holder device that holds the shuttle in the first position and a locking device that continuously prevents the shuttle from rotating relative to the casing.