Clutch Torque Tracking for Precise Zero-Torque Disengagement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current clutch disengagement methods struggle to accurately disengage the clutch at zero torque, leading to driveline oscillations and suboptimal transmission performance.
Innovation Solution
A clutch control system that includes a friction clutch capable of transitioning between fully open, partially open, and fully closed positions, with a control unit monitoring engine torque and a clutch actuator adjusting the clutch position to disengage at zero torque, incorporating safety margins and feedback control for precise disengagement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of time
If clutch disengagement is timed based on predicted zero torque moment, then clutch can be disengaged before the narrow zero torque window, but the prediction often misses the exact moment of zero torque resulting in imprecise disengagement
Solution Approach 1:
The system deliberately reduces engine torque to a negative value before the intended gear shift moment, creating a predetermined torque reduction phase. This preliminary action ensures that the torque passes through zero at a known, predictable time, allowing the clutch to be disengaged precisely at zero torque without relying on inaccurate predictions of the zero torque moment
Solution Approach 2:
The control unit continuously monitors engine torque throughout the torque reduction phase and uses this real-time feedback to determine when torque reaches zero. This feedback mechanism enables precise detection of the zero torque moment and coordinates the clutch disengagement timing accurately, resolving the timing accuracy and detection precision contradiction
2Object-affected harmful factors
If clutch is disengaged exactly at zero torque, then driveline oscillations are avoided, but the narrow duration of zero torque (a few milliseconds) makes reliable timing extremely challenging
Solution Approach 1:
The system deliberately reduces engine torque to a negative value before the intended gear shift moment, creating a predetermined torque reduction phase. This preliminary action ensures that the torque passes through zero at a known, predictable time, allowing the clutch to be disengaged precisely at zero torque without relying on inaccurate predictions of the zero torque moment
Solution Approach 2:
The control unit continuously monitors engine torque throughout the torque reduction phase and uses this real-time feedback to determine when torque reaches zero. This feedback mechanism enables precise detection of the zero torque moment and coordinates the clutch disengagement timing accurately, resolving the timing accuracy and detection precision contradiction
3Reliability
If clutch operates at effectively closed position with dynamically adjusting torque capacity, then clutch slip is prevented during torque transition, but the system complexity increases with continuous monitoring and dynamic adjustment requirements
Solution Approach 1:
The control unit continuously monitors engine torque and uses this feedback to dynamically determine the effectively closed position of the clutch. This feedback loop ensures the clutch maintains appropriate torque capacity throughout the torque transition, preventing clutch slip while managing complexity through a straightforward monitoring and adjustment mechanism
Solution Approach 2:
The clutch operates at an effectively closed position that dynamically adjusts as engine torque changes during the reduction phase. This dynamic operation allows the clutch to adapt its torque capacity to match the changing engine torque, ensuring reliable slip prevention throughout the transition without requiring overly complex control 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 system ensures reliable clutch disengagement at zero torque, reducing driveline oscillations and improving transmission performance by preventing clutch slip and enhancing gear shifts.
Implementation Method 1
a friction clutch (121) capable of transitioning between a fully open (d o ), a partially open, and a fully closed position (d c )
Data Source
Figure 1
Figure 2A~2C
Figure 3
AI summary
A clutch control system for precise clutch disengagement, wherein the disengagement of the clutch is preceded by a deliberate reduction in engine torque, the clutch control system comprising: a friction clutch capable of transitioning between a fully open, a partially open, and a fully closed position; a control unit configured to: monitor the reduction in engine torque to continuously obtain a current engine torque, and determine an effectively closed position of the clutch, wherein the effectively closed position is a partially open position having a torque capacity equal to the current engine torque, thereby preventing clutch slip at the effectively closed position; and a clutch actuator configured to operate the friction clutch at the effectively closed position while the current engine torque is above zero, and disengage the friction clutch to a fully open position as the current engine torque approaches zero.