VVT Phaser Lock Pin Disengagement Rate Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Variable valve timing (VVT) systems face issues with lock pin jamming, sticking, or side-loading during disengagement, which can hinder the smooth operation of the phaser and affect engine performance and fuel economy.
Innovation Solution
Implementing a method that establishes if the phaser is at a lock pin position and rate limits its movement to allow disengagement when the lock pin is jammed, stuck, or subjected to side-loading, using a controller to control the duty cycle and repeat the rate limiting process until successful disengagement.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the lock pin is disengaged quickly to improve response time, then the phaser can change phase angle faster, but the lock pin may jam, stick, or be subjected to side-loading
Solution Approach 1:
The system dynamically adjusts the disengagement speed based on detected conditions. When lock pin engagement is detected, the controller reduces the phaser movement speed to a lower rate, allowing the lock pin to disengage smoothly without jamming or side-loading. This dynamic speed adjustment resolves the contradiction between fast response and reliable disengagement.
Solution Approach 2:
The controller continuously monitors phaser position and lock pin status during disengagement. When the lock pin is detected to be engaged, the system provides feedback to adjust the movement rate, reducing speed to prevent mechanical interference. This feedback mechanism ensures reliable disengagement while maintaining acceptable response time.
2Reliability
If the phaser movement rate is limited to allow lock pin disengagement, then the lock pin can retract safely, but the phaser response time increases
Solution Approach 1:
The system implements dynamic rate limiting that activates only when lock pin engagement is detected. During normal operation without lock pin engagement, the phaser moves at full speed. When lock pin engagement is detected, the movement rate is reduced temporarily, then restored once disengagement is confirmed. This dynamic approach minimizes time loss while ensuring reliable disengagement.
3Stability of the object's composition
If the lock pin is engaged to secure the phaser position, then the phaser remains stable, but the lock pin may jam or stick during disengagement
Solution Approach 1:
The controller detects lock pin engagement conditions before attempting disengagement. When engagement is detected, the system prepares for controlled disengagement by reducing the movement rate in advance. This preliminary action prevents the lock pin from jamming or sticking during the disengagement process, maintaining both stability during engagement and reliability during disengagement.
Data Source
AI summary
A control method for an internal combustion engine of a vehicle that is used with a variable valve timing (VVT) system to promote lock pin disengagement. The method establishes if the VVT is at a lock pin position, establishes if a lock pin is not disengaged out of an associated recess, and can control the rate of movement of the VVT away from the lock pin position so that the lock pin can be disengaged out of the recess.