Electromagnetic Cycloidal Gear Control for Higher Torque Density
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional magnetic cycloidal gear assemblies require large external diameters to achieve equivalent torque capacity, leading to space accommodation issues and potential loss of desirable features, and face challenges with back-drive torque and torque carrying capacity due to magnetic interactions between rotor and stator poles.
Innovation Solution
Employing electromagnets on the stator and controlling their magnetic fields to enhance torque capacity by switching on and off or reversing polarity, reducing negative contributions and optimizing magnetic interactions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If conventional magnetic cycloidal gear assemblies use permanent magnets on both stator and rotor, then magnetic interactions are simplified, but torque capacity is reduced due to negative contributions from repelling magnetic poles
Solution Approach 1:
The patent applies dynamics by transitioning from static permanent magnets to dynamic electromagnets on the stator side. The electromagnets can be selectively energized or de-energized based on the rotor's angular position, allowing the magnetic field configuration to change dynamically throughout the rotation cycle. This dynamic control enables the system to eliminate repelling pole interactions that occur in conventional designs with fixed permanent magnets, thereby increasing torque capacity while managing the added control complexity through position-based switching strategies
Solution Approach 2:
The patent implements parameter changes by modifying the magnetic field strength and polarity parameters of the stator magnets. By controlling the current supplied to each electromagnet, the system can adjust the magnetic flux density and polarity in real-time according to the rotor position. This allows optimization of magnetic interactions at different angular positions, maximizing attractive forces during torque-generating phases and minimizing or eliminating repulsive forces, thus resolving the torque capacity limitation of conventional designs
2Force
If the gear assembly uses a larger external diameter to increase torque capacity, then torque carrying capacity improves, but space accommodation becomes problematic and desirable features may be lost
Solution Approach 1:
The patent achieves higher torque capacity within a compact diameter by changing the magnetic field parameters through selective electromagnet activation. By optimizing the magnetic flux distribution and strength through controlled current supply to different electromagnet groups, the system generates higher torque densities without increasing the physical size of the gear assembly, thus resolving the contradiction between torque capacity and external diameter
Solution Approach 2:
The patent applies local quality by creating non-uniform magnetic field distributions through selective activation of electromagnets at specific angular positions. Rather than using uniform permanent magnets throughout, the system tailors the magnetic field strength and presence locally according to the rotor position and torque requirements. This localized magnetic field optimization allows concentrated torque generation in specific zones, achieving high torque capacity within a smaller overall diameter
3Force
If electromagnets are used instead of permanent magnets, then torque capacity and freewheeling operation are enhanced, but energy consumption increases
Solution Approach 1:
The patent implements periodic action by cyclically energizing and de-energizing the electromagnets in synchronization with the rotor's rotation. Rather than maintaining continuous magnetic fields from all electromagnets, the system activates only the necessary electromagnets at appropriate phases of the rotation cycle. This periodic activation pattern reduces overall energy consumption while maintaining the enhanced torque capacity benefits, as electromagnets consume energy only when actively generating magnetic fields rather than continuously
Solution Approach 2:
The patent uses dynamics to optimize energy consumption by adapting the electromagnet activation pattern to the instantaneous operational requirements. The system dynamically switches electromagnets on and off based on rotor position and load conditions, maintaining high torque capacity when needed while allowing energy-saving freewheeling modes when appropriate. This dynamic control strategy balances the energy consumption trade-off against the torque capacity enhancements provided by electromagnets
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
Enhances torque capacity and allows for freewheeling operation, addressing space and torque capacity challenges while maintaining desirable features and reducing back-drive torque.
Implementation Method 1
either each of the first magnetic devices or each of the second magnetic devices includes a respective electromagnet configured to produce a respective magnetic field in accordance with a respective current passing therethrough
Implementation Method 2
magnetic interactions between those of the magnetic pole pairs of the stator 12 and rotor 14 that are closest together depending upon the relative positioning of the stator and rotor at any given time, prevent relative 'slipping' motion between the stator and rotor
Data Source
AI summary
The present disclosure relates to electromagnetically-controlled magnetic cycloidal gear assemblies configured to achieve enhanced torque capacity, and methods of operating same. In one example embodiment, a method includes sensing a position of a cycloid relative to a stator, where the stator includes a plurality of electromagnets, and the cycloid includes a plurality of permanent magnets. Also, the method includes determining respective torque characteristics concerning the respective electromagnets based upon the sensed position, where the respective torque characteristic that is determined concerning each respective one of the electromagnets is indicative of a respective relative position of the respective electromagnet in relation to a respective closest one of the permanent magnets. The method additionally includes outputting from a controller, for receipt respectively at least indirectly by the respective electromagnets or respective control devices coupled thereto, a plurality of output signals respectively based at least in part upon the respective torque characteristics.