Torque Vectoring Apparatus Using Compound Planetary Gears
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing torque vectoring systems in vehicles face challenges in achieving optimal torque control and minimizing power loss, especially in high-performance electric vehicles, where precise control of torque distribution between wheels is necessary for improved agility and stability.
Innovation Solution
A torque vectoring apparatus comprising a speed reduction device, a differential device, and a torque vectoring device with a torque vectoring control motor and compound planetary gear sets, which allows for adjustable torque ratio distribution between left-side and right-side output shafts, minimizing power loss and enhancing control by disconnecting torque transmission when excessive vehicle speed is reached.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If a traditional differential device is used to distribute torque to left-side and right-side drive wheels, then the basic torque distribution function is achieved, but the ability to actively control torque distribution ratio for improved agility and handling performance is lost
Solution Approach 1:
The patent combines a torque vectoring device with a differential device to create an integrated system. The torque vectoring device includes a torque vectoring control motor and planetary gear sets that are merged with the differential device's structure, allowing both basic torque distribution and active torque vectoring control to be achieved in a single unified system rather than separate components.
Solution Approach 2:
The differential device is designed to perform multiple functions: it provides the basic torque distribution function while also incorporating torque vectoring capability through the integrated torque vectoring device. This multi-functionality allows the system to both distribute torque passively through differential action and actively control torque distribution ratio for improved handling.
2Reliability
If torque vectoring control is implemented to improve cornering performance, then vehicle dynamics are enhanced, but power loss increases due to additional torque transmission path
Solution Approach 1:
The patent extracts the torque vectoring control function as a separate controllable module within the differential device. By using a torque vectoring control motor that can be independently activated, the system only engages the additional torque transmission path when torque vectoring is needed for cornering or stability control, rather than continuously operating additional components that would cause constant power loss.
Solution Approach 2:
The torque vectoring control motor and associated planetary gear sets are designed to be dynamically engaged or disengaged based on driving conditions. The system actively adjusts torque distribution only when needed for cornering performance or vehicle stability, rather than maintaining a fixed additional torque path that would continuously increase power loss during normal driving.
3Measurement precision
If a torque vectoring device with multiple planetary gear sets is added to control torque ratio, then torque distribution precision is improved, but device complexity and size increase
Solution Approach 1:
The patent employs nested planetary gear sets where smaller planetary gear mechanisms are integrated within or alongside larger differential components. The torque vectoring device uses planetary gear sets that are nested within the differential device structure, allowing precise torque ratio control through compact, space-efficient arrangements rather than requiring separate, bulky gear trains.
Solution Approach 2:
The torque vectoring control system uses asymmetric planetary gear configurations where the left-side and right-side torque paths have different gear ratios or mechanical advantages. This asymmetric design allows precise independent control of torque distribution to each wheel, enabling accurate torque vectoring while using a compact number of planetary gear sets rather than symmetric, redundant arrangements.
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 apparatus achieves improved cornering performance and stability in electric vehicles by optimizing torque distribution and minimizing power loss, applicable to various electric vehicle types including hybrid and plug-in hybrid models, thereby enhancing fuel efficiency.
Implementation Method 1
a first compound planetary gear set including first and second planetary gear sets, and a second compound planetary gear set including third and fourth planetary gear sets
Data Source
AI summary
A drive torque received from a power source is split and output to first and second output shafts through a torque vectoring apparatus including a torque vectoring device that controls a torque ratio of split torques, where the torque vectoring device includes a control motor, a first compound planetary gear set including first and second planetary gear sets having a shared first rotation element fixed to a housing, a second rotation element, and a third rotation element connected to the first output shaft, and a second compound planetary gear set including third and fourth planetary gear sets having a shared fourth rotation element connected to the control motor, a fifth rotation element connected to a second output shaft, and a sixth rotation element connected to the second rotation element.