Shift Control Device with Elastic Intermediary for Smooth Dog Engagement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electric shift control devices for straddle-type vehicles face challenges in smooth shift change due to issues with dog engagement and disengagement, requiring complex feedback methods and additional mechanisms like spring mechanisms, which can lead to slow shift speeds and maintenance complexities.
Innovation Solution
A shift control device with an actuation force transmission mechanism comprising a biasing mechanism and a stopper mechanism, allowing for smooth shift change by interposing the transmission mechanism between the shift actuator and shift shaft, enabling the dog to be engaged and disengaged efficiently without modifying the engine case, and facilitating easy maintenance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a feedback method using shift cam angle detection is used to adjust the shift actuator operation angle, then the dog can properly disengage and engage, but the shift speed becomes slow and the device complexity increases
Solution Approach 1:
A lost motion mechanism with an elastic member is introduced as an intermediary between the shift actuator and the shift shaft. This elastic member absorbs the impact during dog engagement and allows the shift shaft to rotate smoothly using resilient force, eliminating the need for complex feedback control while maintaining reliable dog engagement and improving shift speed
2Reliability
If a spring mechanism is interposed between the shift actuator and shift shaft to prevent dog rotation, then the dog can be prevented from rotating during abutment, but the device complexity increases and maintenance becomes difficult
Solution Approach 1:
The lost motion mechanism with elastic member serves as a simple intermediary that naturally prevents dog rotation during abutment through its elastic properties, without requiring complex transmission mechanisms. The elastic member absorbs shocks and allows smooth operation while keeping the overall structure simple and easy to maintain
3Reliability
If the stroke amount of the shift actuator is increased to ensure dog disengagement, then the dog can be disengaged even under high load, but the shift speed becomes slower
Solution Approach 1:
The lost motion mechanism introduces dynamic elasticity into the transmission system. The elastic member can dynamically adjust to load conditions, providing sufficient force for dog disengagement under high load while allowing rapid return and smooth operation, thereby maintaining both reliability and speed without requiring increased actuator stroke
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 solution enables smooth shift changes even when dog disengagement is difficult, reducing maintenance requirements and allowing for compact installation, thus improving shift speed and reliability.
Implementation Method 1
any overload is applied to the elastic member and results in elastic deformation of the elastic member. Therefore, when the shift shaft is rotationally driven by the resilient force
Data Source
AI summary
A transmission mechanism is provide that can be interposed between a shift actuator and a shift shaft. The mechanism can include first and second coupling parts that can be coupled for movement relative to each other; a biasing mechanism that can be configured for urging the first and second coupling parts toward a neutral position; and a stopper mechanism that can be configured for stopping the relative movement of one of the first and second coupling parts when moved relatively from the neutral position against urging force of the biasing mechanism. When the shift actuator is stroked by a predetermined amount, a dog can be compulsorily disengaged as the first and second coupling parts are moved together by the stopper mechanism, and engaged as one of the first and second coupling parts moves relatively against the urging force, for allowing smooth shift change.