Vehicle Shift Control Device Overlapping Neutral to Target Gear Transitions
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Solution Overview
Problem
Existing gear shift control devices for automatic transmissions in vehicles take too long to transition from a neutral coasting state to a traveling state, leading to delayed acceleration response due to the sequential shift process from a neutral state to the final target gear stage.
Innovation Solution
A shift control device that sets a virtual gear stage based on input rotation speed and a pre-shift gear stage on the lower-speed side of the current gear stage, allowing simultaneous execution of the first shift from the neutral state to the current gear stage and the second shift to the target gear stage, thereby reducing overall shift time and improving acceleration response.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If sequential shift control is used from neutral state to final target gear stage, then shift control simplicity is maintained, but shift time increases and acceleration response deteriorates
Solution Approach 1:
The system performs preliminary actions by initiating the first shift from neutral state to current gear stage before the second shift to target gear stage is complete. The electronic control unit starts the first shift control process early, allowing overlapping execution of multiple shift operations, which reduces total shift time without requiring complex hardware modifications
Solution Approach 2:
The invention maintains continuous useful action by allowing the first and second shift control processes to overlap and execute simultaneously. Instead of completing one shift before starting the next, the system continues the first shift process while initiating the second shift, ensuring that the transmission system is continuously progressing toward the target gear stage without idle waiting periods
2Ease of operation
If intermediate target shift stage is set during transition from neutral state, then shift process is divided into stages, but overall shift time increases due to sequential execution
Solution Approach 1:
The electronic control unit initiates the first shift from neutral state to current gear stage as a preliminary action before the second shift to target gear stage begins. This preliminary shift is started early based on predicted needs, allowing the system to be already partially shifted when the final target is determined, thereby reducing total response time
Solution Approach 2:
The system dynamically adjusts shift control by allowing overlapping execution of multiple shift processes based on real-time conditions. The control strategy changes from rigid sequential execution to flexible concurrent execution, where the first and second shift processes can run simultaneously with dynamic coordination of clutch engagement and disengagement timing
Data Source
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AI summary
Provided is a shift control device for a vehicle in which an automatic transmission in which a gear stage is set based on data showing traveling states including at least a driving demand is mounted, the shift control device for a vehicle setting a neutral state where power is not transmitted by releasing an engagement mechanism engaged such that a predetermined gear stage is set in the automatic transmission when the driving demand becomes equal to or less than a predetermined value determined in advance during traveling, in which the shift control device for a vehicle is configured such that a virtual gear stage as an input rotation speed close to an input rotation speed of the automatic transmission in the neutral state is obtained based on a vehicle speed at a time point when the virtual gear stage is obtained and a gear ratio at a gear stage allowed to be set in the automatic transmission when a target gear stage based on the driving demand is set with the neutral state eliminated by the driving demand exceeding the predetermined value during the traveling in the neutral state, and the shift control device for a vehicle is configured such that control of a second shift toward the target gear stage is initiated during a first shift between a current gear stage to be set based on the data showing the traveling states during the elimination of the neutral state and the virtual gear stage.