Shift Control Device Reducing Clutch Engagement Shock
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing shift control devices that use a single actuator for clutch disengagement/engagement and shift movement fail to effectively reduce shift shock due to rotational discrepancies and individual differences in device dimensions, leading to potential halfway engagement during high-speed rotation.
Innovation Solution
Implementing a control system that adjusts the rotational speed of the shift shaft by setting specific rotational positions and speeds, including a low-speed phase after a high-speed phase during clutch engagement, and using a worm gear unit with self-locking function to stabilize motor operation, thereby reducing shock and accommodating dimensional variations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single actuator is used for both clutch disengagement/engagement and shift movement, then device complexity is reduced, but shift shock reduction capability deteriorates due to rotational discrepancies and individual dimensional variations
Solution Approach 1:
The patent segments the control process into multiple phases: a first rotation phase at first rotational speed, and a second rotation phase at second rotational speed. This temporal segmentation allows the single actuator to perform both clutch engagement and shift movement functions while reducing shift shock by adjusting rotational speed at appropriate moments.
Solution Approach 2:
The patent dynamically adjusts the rotational speed of the shift shaft during operation. The rotational speed is changed from a first speed to a second speed based on the operational phase, enabling the system to adapt to different requirements (clutch engagement vs. shift movement) using a single actuator, thereby resolving the contradiction between device simplicity and shock control reliability.
2Productivity
If the shift shaft rotates at high speed during clutch engagement, then shift movement is completed faster, but shift shock increases due to rotational position discrepancies
Solution Approach 1:
The patent implements periodic action by dividing the rotation into distinct phases with different speeds. The shift shaft rotates at a first rotational speed during the first phase, then at a second rotational speed during the second phase. This periodic variation in rotational speed allows fast shift movement while preventing excessive shock during clutch engagement.
Solution Approach 2:
The patent changes the rotational speed parameter during operation. By switching from a first rotational speed to a second rotational speed based on the operational phase, the system achieves both fast shift movement and reduced shock, resolving the contradiction between productivity and harmful factors.
3Manufacturing precision
If dimensional variations are not compensated for, then manufacturing precision requirements are relaxed, but clutch engagement reliability deteriorates due to halfway engagement
Solution Approach 1:
The patent uses feedback from a detection device that monitors the rotational position of the shift shaft. Based on this feedback, the control device adjusts the rotational speed and timing to ensure proper clutch engagement even when dimensional variations exist. This feedback mechanism compensates for manufacturing tolerances and prevents halfway engagement, maintaining reliability without requiring tight manufacturing precision.
4Device complexity
If rotational speed is not adjusted during clutch engagement, then control simplicity is maintained, but shift shock reduction effectiveness deteriorates
Solution Approach 1:
The patent introduces dynamic speed adjustment as a control mechanism. The rotational speed is varied from a first speed to a second speed based on the operational phase, achieving effective shift shock reduction. While this adds some control complexity, it remains relatively simple compared to using multiple actuators, thus resolving the contradiction between control simplicity and shock reduction effectiveness.
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 effectively reduces shift shock and ensures smooth clutch engagement by adjusting rotational speeds and positions, and stabilizes motor control, even with individual device variations, enhancing ride comfort and operational reliability.
Implementation Method 1
a worm gear unit with self-locking function to stabilize motor operation
Data Source
AI summary
A shift control device is provided for reducing a shock generated at a clutch engagement moment in a gearshift operation in a straddle type vehicle having a shift control device that makes the clutch operation and the gearshift operation using the power of an actuator. The actuator is controlled based upon a rotational position and a speed of a shift shaft. When the rotational position of the shift shaft is located between a first position and a second position, the shift shaft is rotated at a speed slower than a rotational speed at which the shift shaft is rotated before reaching the first position to engage a gearshift clutch at a low speed. The first position and the second position are set in such a manner that the gearshift clutch is in a halfway engaged state when the shift shaft is located at a rotational position between the first position and the second position.