Deformable Drive Roller for Low-Stress Wheel Torque Transmission
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing drive actuator architectures for aircraft wheels face safety concerns due to mechanical stress, complexity, and reduced service life from oscillations in torque transmission, particularly when integrating components that undergo deformation and high vibrations.
Innovation Solution
A drive roller with a rigid frame, deformable bearing bodies, and undulating surfaces that cooperate with a rolling track on the wheel rim, allowing for torque transmission through both friction and meshing, which reduces radial force and local stresses, enhancing robustness and longevity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a rigid frame with deformable bearing bodies is used, then the drive roller can compensate for relative displacements and misalignments, but the structure becomes more complex
Solution Approach 1:
The patent changes the physical state of the bearing bodies from rigid to deformable, allowing them to change shape and absorb relative displacements between the drive roller and wheel rim. This parameter change enables the structure to adapt to misalignments without adding complex mechanical adjustment mechanisms.
Solution Approach 2:
The patent uses composite construction by combining rigid frame elements with deformable bearing bodies made of elastomeric material. This composite approach allows different parts of the structure to perform different functions: the rigid frame provides structural support while the deformable bearing bodies provide adaptation and stress distribution.
2Adaptability or versatility
If torque is transmitted through friction only, then the drive roller can adapt to deformations, but the radial force required increases
Solution Approach 1:
The patent merges two torque transmission mechanisms: friction between the deformable bearing bodies and the raceway, and mechanical meshing through the undulating surfaces. This combination allows the system to benefit from both the adaptability of friction and the efficiency of positive engagement, reducing the required radial force.
Solution Approach 2:
The patent introduces undulating surfaces with curved profiles that engage with corresponding features on the raceway. These curved surfaces enable mechanical meshing that complements the friction-based torque transmission, allowing more efficient force transfer with reduced radial loading.
3Device complexity
If the drive roller uses rigid bearing bodies, then the structure is simpler, but the service life is reduced due to high local stresses
Solution Approach 1:
The patent changes the material property of the bearing bodies from rigid to deformable elastomeric material. This parameter change allows the bearing bodies to deform under load, distributing stresses over larger areas and reducing peak local stresses that would otherwise lead to premature failure in rigid structures.
Solution Approach 2:
The patent employs composite construction combining rigid structural elements with deformable elastomeric bearing bodies. The elastomeric material provides shock absorption and stress distribution capabilities that extend service life, while the rigid frame maintains structural integrity.
4Adaptability or versatility
If connecting rods are used to couple the reduction unit to the wheel, then the architecture is more flexible, but the position inaccuracy requires bulky connecting rods
Solution Approach 1:
The patent changes the coupling mechanism from rigid connecting rods to deformable elastomeric bearing bodies. This parameter change allows the coupling to accommodate position variations and misalignments through material deformation rather than requiring oversized mechanical components with adjustment mechanisms.
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 provides a mechanically robust drive roller that adapts to relative displacements and deformations, reducing stress and increasing contact surface, leading to improved torque transmission and extended service life by homogenizing stresses and using deformable materials to compensate for misalignments.
Implementation Method 1
The bearing bodies made of deformable material make it possible to compensate for relative displacements and misalignments between the drive roller and the raceway
Implementation Method 2
The combination of the fixed bars of the rigid frame, of the external rigid rings and of the deformable bearing bodies makes it possible to transmit part of the torque by cooperation with the undulations of the raceway, the other part of the torque being transmitted by friction
Data Source
Figure 1~2
Figure 3
Figure 4
AI summary
Roller (1) comprising: - a rigid frame (4) defining a hub (5) for the rotation of the roller around an axis of rotation X and a plurality of bars (6) regularly arranged around the hub (5) in s extending in the direction of the X axis; - pads (10) each threaded onto one of the bars (6) and each comprising an outer rigid ring (11) surrounding a pad body (12) of deformable material.