Torque Control for Multiple-Disc Clutch
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In driving force transmission devices with multiple-disc clutches lubricated by a lubricant, there is a deviation between the commanded torque and the actual output torque, especially during increases in command torque, which affects the accuracy of torque transmission.
Innovation Solution
A control device is implemented that computes a torque command value based on vehicle state, calculates a current command value corresponding to the torque command, and adjusts this value by a correction amount based on the change rate of the torque command, supplying the corrected current to a pressing mechanism to reduce deviations and enhance transmission accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the command torque is increased rapidly, then the response speed of torque transmission is improved, but the deviation between command torque and actual output torque increases
Solution Approach 1:
The control device performs preliminary action by predicting the required current command value based on the change rate of torque command value before the actual torque transmission occurs. This allows the pressing mechanism to be pre-adjusted, reducing the deviation between command torque and actual output torque during rapid torque increases while maintaining fast response speed.
2Measurement precision
If the current command value is increased to match rapid torque command increases, then the torque transmission accuracy is improved, but the response lag occurs
Solution Approach 1:
The control device applies dynamics by adjusting the current command value dynamically based on the change rate of torque command value. When torque command increases rapidly, the control device adds a correction amount proportional to the change rate, allowing the system to adapt quickly to torque demands without fixed response delays, thereby reducing response lag while maintaining accuracy.
3Measurement precision
If a correction amount based on torque command change rate is added, then the deviation between command and actual torque is reduced, but the control complexity increases
Solution Approach 1:
The control device implements parameter changes by modifying the current command value based on the change rate of torque command value. This involves calculating the derivative of torque command with respect to time and adding a proportional correction amount. This approach achieves high torque transmission accuracy through a relatively simple control algorithm that adjusts key parameters dynamically without requiring complex control systems.
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
This configuration reduces the difference between commanded and actual output torque, thereby improving the accuracy of torque transmission in multiple-disc clutches.
Implementation Method 1
a multiple-disc clutch in which frictional sliding among clutch plates is lubricated by a lubricant
Implementation Method 2
frictional sliding among clutch plates is lubricated by a lubricant
Implementation Method 3
a pressing mechanism that presses the multiple-disc clutch at a pressing force depending on an electric current that is supplied
Data Source
AI summary
A driving force transmission device includes an input rotation member and output rotation member, a multiple-disc clutch, a pressing mechanism, and a control device that includes a current supply circuit. The control device is configured to compute a torque command value based on a state of a vehicle, the torque command value being a driving force that needs to be transmitted by the multiple-disc clutch, to compute a current command value, to correct the current command value, and to control the current supply circuit such that an electric current depending on the current command value is supplied to the pressing mechanism. The control device is configured to perform the correction so as to increase or decrease the current command value by a correction amount depending on a change rate of the torque command value.