Countershaft Synchronization Module With Selective Coupling and Lock-Up Brake
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle transmission systems that use reversible electric machines to synchronize and drive countershafts face issues of increased fuel consumption and safety risks due to continuous drag torque and potential battery damage during transient gear ratio changes.
Innovation Solution
A module comprising a bearing part, a coupling device with input and output elements, and a lock-up device that allows the reversible electric machine to be uncoupled during non-transient phases and acts as a gearbox brake in the lock-up state, reducing engine consumption and avoiding demands on the electric machine, especially during failures or maximum battery charge.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the reversible electric machine is permanently coupled to the countershaft to assist with synchronizing during transient phases, then the synchronization performance is improved, but the fuel consumption increases due to continuous drag torque
Solution Approach 1:
The coupling device transitions from a static permanent coupling to a dynamic variable coupling, allowing the reversible electric machine to be connected only when needed for synchronization during transient phases, and disconnected during steady-state operation to eliminate continuous drag torque and reduce fuel consumption
Solution Approach 2:
The coupling device engages and disengages periodically based on operational phases - engaged during transient synchronization phases and disengaged during steady-state operation, creating an on-demand operation pattern that reduces energy consumption while maintaining synchronization performance
2Reliability
If the reversible electric machine is permanently coupled to the countershaft to assist with synchronizing, then the synchronization capability is improved, but the safety deteriorates in case of machine malfunction or battery overload
Solution Approach 1:
The coupling device acts as an intermediary between the reversible electric machine and the countershaft, providing a mechanical decoupling mechanism that isolates the countershaft from the electric machine in case of malfunction or battery overload, thereby eliminating safety risks while preserving synchronization capability when the system is properly functioning
3Speed
If the reversible electric machine is used to brake the countershaft during transient phases, then the synchronization speed is improved, but the device complexity increases due to continuous connection requirements
Solution Approach 1:
The system incorporates a dynamic coupling mechanism that automatically connects the reversible electric machine to the countershaft only during transient synchronization phases and disconnects during steady-state operation, maintaining high synchronization speed capability while reducing overall system complexity through selective engagement
Data Source
AI summary
A module for a system for driving and synchronizing a countershaft of a transmission gearbox. The module includes a coupling device having an input element intended to be rotationally coupled to a reversible electric machine and an output element intended to be rotationally coupled to the countershaft. The coupling device has a coupled state in which the clutch device is able to transmit torque between the input element and the output element and an uncoupled state in which the input element and the output element are uncoupled. Also included is a lock-up device which has a lock-up state in which said lock-up device blocks the rotation of the input element of the clutch device, and a released state in which said lock-up device allows the input element to rotate.