Magnetic Disc Torque Structure for Compact MR Fluid Braking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing torque generation apparatus using magnetic viscous fluids face challenges in size reduction while maintaining a large shearing force, as they often require a compact configuration with sealed chambers, permanent magnets, and coils, which limits miniaturization and efficiency.
Innovation Solution
A torque generation apparatus with a magnetic disc, first and second yokes, and a coil, where the magnetic disc has a torque increasing portion on its outer circumferential area, allowing for a wider magnetic flux path and increased shearing force without increasing the apparatus size, utilizing a magnetic gap and specific yoke configurations to enhance magnetic field distribution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If a sealed chamber with permanent magnets and coils is used to generate torque with magnetic viscous fluid, then the shearing force is increased, but the apparatus size cannot be reduced
Solution Approach 1:
The patent extracts and eliminates the permanent magnets from the conventional sealed chamber configuration. By using only electromagnetic coils to generate the magnetic field and placing the magnetic viscous fluid in an open space between a magnetic disc and yoke, the apparatus achieves torque generation without requiring a sealed chamber and permanent magnets, thereby reducing overall size while maintaining shearing force capability
Solution Approach 2:
The patent introduces magnetic viscous fluid as an intermediary substance between the magnetic disc and yoke. This fluid mediates the interaction between the magnetic field generated by the coils and the mechanical rotation, allowing torque to be generated through magnetic field interaction without direct mechanical contact or sealed chamber constraints
2Stability of the object's composition
If the disc diameter is made larger than the coil diameter to reverse magnetic field direction, then the magnetic field distribution is improved, but the apparatus size increases
Solution Approach 1:
The patent applies local quality by providing torque increasing portions only in the outer circumferential area of the magnetic disc, while the inner circumferential area maintains a different structure. This localized modification optimizes magnetic field distribution and shearing force generation without requiring the entire disc to be larger than the coil, thus avoiding overall size increase
Solution Approach 2:
The patent addresses magnetic field direction reversal not by increasing disc diameter in the radial dimension, but by utilizing the axial dimension through the thickness of the magnetic disc and strategic placement of torque increasing portions. This dimensional approach allows magnetic field control without proportional increases in overall apparatus size
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 enables a significant increase in shearing force while maintaining a compact size, allowing for efficient torque generation with improved braking torque performance and reduced initial torque, making it suitable for size reduction and high responsiveness.
Implementation Method 1
A magnetic viscous fluid is placed between the magnetic disc and the first yoke and the second yoke
Implementation Method 2
a coil disposed so as to overlap with the magnetic disc when viewed in a direction along the first direction
Data Source
AI summary
A torque generation apparatus includes a magnetic disc rotatable about a rotation axis, a first yoke, a second yoke, a magnetic viscous fluid placed between the magnetic disc and the first yoke and the second yoke, a coil, and a third yoke. The coil overlaps with the magnetic disc as viewed along the rotation axis. The third yoke constitutes a magnetic path of a magnetic field generated by the coil together with the first yoke and the second yoke. The magnetic disc includes a torque increasing portion at at least one of a surface facing the first yoke and a surface facing the second yoke. The torque increasing portion is provided in an outer circumferential area of the magnetic disc in a radial direction and causes a shearing force to a cluster of the magnetic viscous fluid to become larger than that in the inner circumferential area.