CVT Kick-Down Control for Aggressive Driving Feel
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional continuously variable transmissions do not provide drivers with a tangible feeling of increased engine output during kick-down operations, limiting the aggressive driving experience.
Innovation Solution
A shift control device that includes a switchover operation accepting unit and a kick-down control unit, which executes multiple kick-down control modes to adjust gear ratios and engine speed, allowing drivers to feel the results of engine output property switches more vigorously during kick-down operations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If kick-down control is executed to increase engine speed during rapid acceleration, then engine output is increased, but the driver cannot physically feel the results of switching operations regarding engine output properties
Solution Approach 1:
The system dynamically adjusts the gear ratio control strategy based on the selected output mode. In power mode, the control unit executes kick-down control more aggressively and maintains lower gear ratios longer to keep engine speed in the high-speed region, creating a more vigorous driving feel. The pulley groove widths are dynamically adjusted to achieve this effect while maintaining reliable engine output delivery across different driving conditions.
2Speed
If gear ratio is changed to low side to increase engine speed during kick-down control, then engine speed increases, but the switching operation feeling is not enhanced
Solution Approach 1:
The control unit changes the control parameters for gear ratio based on the selected output mode. In power mode, the target gear ratio is set lower and the kick-down control is executed more vigorously compared to normal mode. This parameter change allows the engine speed to increase more rapidly and be maintained at higher levels, providing the driver with a more intense feeling of acceleration and switching operation.
Data Source
AI summary
A shift control device includes a kick-down control unit that, in the case where the accelerator is depressed to a certain level or beyond, executes a first kick-down mode, in which a gear ratio of the continuously variable transmission is changed to a low side to increase the engine speed. In the case where, during execution of the first kick-down mode, a switchover operation is accepted to switch the output properties such that output of the engine is increased, the kick-down control unit again determines whether or not to start the first kick-down control again.