Electronic Locking Differential Coil Boosting for Faster Engagement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrically locking differentials in automotive drivelines face challenges in improving spring strength and reducing engagement time while maintaining cost-effectiveness, as they often require larger, more expensive coils and are prone to inadvertent actuation and torque trapping issues.
Innovation Solution
The use of a boost converter circuit to temporarily increase solenoid voltage to 48V, powered by a 48V energy storage capacitor, allows for a smaller coil with increased pulling power and a stronger spring, enabling faster engagement and disengagement, while reducing system costs and weight.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a larger coil is used to increase pulling power and spring strength, then the engagement force and reliability are improved, but the system cost and weight increase
Solution Approach 1:
The patent applies periodic action by using a boost converter to deliver high-voltage pulses only during the engagement phase when the differential needs to be locked. The capacitor is charged during normal operation and then discharged in a controlled pulse to actuate the solenoid, providing high force only when needed rather than continuously. This resolves the contradiction by enabling strong engagement force without requiring a continuously powered large coil, thus reducing weight and cost while maintaining strength during critical operations.
2Speed
If a larger coil is used to reduce engagement time, then the response speed is improved, but the system cost and complexity increase
Solution Approach 1:
The boost converter delivers high-voltage pulses periodically only during engagement events rather than continuously powering a large coil. The capacitor charges during normal operation and discharges in controlled bursts to achieve fast engagement when needed, reducing both engagement time and system complexity compared to continuously operating high-power systems.
Solution Approach 2:
The capacitor is charged in advance during normal vehicle operation, storing energy before it is needed. When engagement is required, the pre-charged capacitor immediately delivers high voltage to the solenoid, achieving fast response without requiring a continuously powered high-capacity coil, thus reducing system complexity while improving engagement speed.
3Force
If continuous high voltage is applied to the coil, then the engagement force is improved, but the energy consumption and heat generation increase
Solution Approach 1:
Instead of continuous high voltage application, the system uses periodic high-voltage pulses from the boost converter only during engagement events. The capacitor stores energy during normal operation and releases it in controlled pulses when the differential needs to be locked, providing strong engagement force only when needed rather than continuously, thus dramatically reducing overall energy consumption while maintaining sufficient force during critical moments.
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
This solution results in faster engagement times, improved torque trapping, reduced inadvertent actuation, and cost savings by using less copper wiring, with the ability to maintain robust disengagement even under dynamic events, enhancing the overall performance and durability of the differential system.
Implementation Method 1
an energy storage capacitor that powers the coil during at least a portion of engagement of the lock ring with the gears
Implementation Method 2
The use of a boost converter circuit to temporarily increase solenoid voltage to 48V
Data Source
AI summary
An electronic locking differential includes a lock ring and a coil that moves the lock ring to engage gears of the electronic locking differential, an energy storage capacitor that powers the coil during at least a portion of engagement of the lock ring with the gears, and a controller. The controller charges the energy storage capacitor to a first predefined voltage prior to the engagement.