Connectable Four-Wheel Drive System for Traction Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
High-performance sports cars with rear-drive and self-locking differential systems face difficulties in poor road-holding conditions, and existing connectable four-wheel drive solutions are complex and costly to produce, with potential driver errors in engaging four-wheel drive during adverse conditions.
Innovation Solution
A connectable four-wheel drive vehicle system that includes a power train with a dry or oil-bath clutch, a gear train, and a differential, controlled by a hydraulic or electromechanical actuator, which automatically adjusts torque distribution between rear and front wheels based on wheel speed differences to enhance traction without driver intervention.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a permanent four-wheel drive system is installed, then traction in poor road-holding conditions is greatly improved, but torque loss of the drive system increases permanently and vehicle performance becomes unsuitable for good road-holding conditions
Solution Approach 1:
The patent implements a dynamic four-wheel drive system where the front drive wheels are connected to the drive shaft through a clutch that can be engaged or disengaged based on driving conditions. The control system automatically engages the clutch when wheel slip is detected (indicating poor road-holding conditions) and disengages it when conditions improve, thereby dynamically adapting the drive configuration to minimize torque loss while maintaining traction when needed.
2Adaptability or versatility
If a connectable four-wheel drive system is provided to allow driver choice between rear drive and four-wheel drive, then flexibility in road conditions is improved, but device complexity and production cost increase
Solution Approach 1:
The patent eliminates the need for manual driver intervention by implementing an automatic control system that monitors wheel rotation speeds and autonomously engages or disengages the front drive clutch based on detected wheel slip conditions. This self-service approach maintains adaptability to different road conditions while significantly reducing device complexity compared to manual connectable systems, as it removes the need for complex driver interfaces, sensors for ice detection, and manual engagement mechanisms.
3Reliability
If a connectable four-wheel drive system is installed, then traction in poor conditions can be activated, but the driver may fail to see ice on the road and fail to connect the four-wheel drive in time
Solution Approach 1:
The patent implements a feedback control system using wheel speed sensors that continuously monitor the rotation speeds of all four wheels. When the system detects a difference in wheel speeds indicating wheel slip (a sign of poor road-holding conditions), it automatically triggers clutch engagement to connect the front drive wheels. This closed-loop feedback mechanism eliminates the time delay associated with driver perception and manual action, responding instantly to changing road conditions.
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 system provides optimal traction in all road conditions without driver assistance, is cost-effective, compact, and lightweight, with minimal torque loss, and automatically engages front-wheel drive only when rear wheels skid, ensuring safe and efficient vehicle performance.
Implementation Method 1
A self-locking (first) differential 11 is cascade-connected to gearbox 10, and from which extend two axle shafts 12, each integral with a respective rear drive wheel 3. More specifically, as shown in FIG. 2, a primary shaft 13 of gearbox 10 is integral with propeller shaft 9, and a secondary shaft 14 of gearbox 10 is connected to self-locking differential 11.
Data Source
AI summary
A connectable four-wheel drive vehicle includes an engine having a gear shaft; two main drive wheels connected permanently to the drive shaft by interposition of a gearbox having a first clutch; and two secondary drive wheels selectively connectable to the drive shaft by a connectable drive system. The connectable drive system includes a second clutch which, on one side, is connected with a fixed velocity ratio to the drive shaft upstream from the gearbox, and on another side, is connected with a fixed velocity ratio to the secondary drive wheels.