Vehicle Transmission Shift Cam Curved Surface Actuator Load
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle transmission systems face challenges in easily controlling the actuator and reducing the load of the actuator, particularly due to the abrupt torque requirements when changing gearshift positions, which complicates the control and increases the load on the actuator.
Innovation Solution
A vehicle transmission system with a gearshift holding mechanism that includes a rotatable shift cam and a stopper member with indented portions, where the actuator generates torque to extrude the stopper member from an indented portion and then reduces torque after contact with a circular-arc curved surface, allowing smoother control and reduced load.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the toothed portion of the shift stopper plate has an approximately triangular shape, then the gearshift holding function is achieved, but the output power of the actuator must be increased and the control becomes difficult
Solution Approach 1:
The patent replaces the triangular toothed portion with a curved surface having a radius of curvature R. This curved surface allows the shift stopper arm to climb smoothly without abrupt torque changes, enabling easier actuator control while maintaining the gearshift holding function through the biased roller that engages with the curved surface at predetermined positions.
2Reliability
If the toothed portion of the shift stopper plate has an approximately triangular shape, then the gearshift holding function is achieved, but the load of the actuator increases
Solution Approach 1:
The curved surface with radius of curvature R replaces the triangular toothed portion, allowing the shift stopper arm to climb gradually rather than overcoming an abrupt peak. This reduces the maximum torque required from the actuator while still achieving reliable gearshift holding through the biased roller engagement at specific positions on the curved surface.
3Productivity
If the shift stopper arm climbs over the toothed portion, then the gearshift position changes, but the torque necessary to rotate the shift cam is abruptly reduced requiring immediate power reduction or setting to zero
Solution Approach 1:
The curved surface provides a gradual transition path for the shift stopper arm, allowing the actuator to reduce torque progressively rather than abruptly. The biased roller maintains contact with the curved surface throughout the movement, enabling smooth torque modulation while achieving reliable gearshift position changes.
Solution Approach 2:
The biased roller acts as an intermediary between the shift stopper arm and the curved surface, maintaining continuous contact and enabling smooth torque transition. The biasing force ensures the roller stays engaged with the curved surface, facilitating gradual torque reduction while the shift cam rotates to the new position.
Data Source
AI summary
A vehicle transmission system includes a shift cam rotated by rotary power from an output torque of a gearshift actuator motor to change a gearshift position and a rotational position holding mechanism configured to hold a rotational position of the shift cam. The rotational position holding mechanism has a rotatable member that is rotated in synchronization with the shift cam and has a plurality of indented portions along a rotational direction and a stopper member inserted into the indented portion of the rotatable member to hold a rotational position of the rotatable member. An unindented portion between the plurality of indented portions on the outer circumferential surface of the rotatable member is formed on a circular arc curved surface concentric on a rotation center line.