Marine Engine Control Circuit for Smooth Gear Shifts
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current marine propulsion systems face challenges in smoothly transitioning between gear shifts, often resulting in noise, shock, and increased load due to high engine speeds, which can lead to instability and potential stalling when shifting from forward or reverse to neutral gear.
Innovation Solution
A control circuit system that senses the engine speed and shift linkage position, delaying shift interrupt control strategies until the engine reaches a threshold speed, thereby reducing engine speed to facilitate smoother gear changes and prevent stalling.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If engine speed is reduced to facilitate shift change, then noise and load during gear shifts are reduced, but engine stability may deteriorate and stalling may occur
Solution Approach 1:
The control circuit delays the execution of shift interrupt control strategies until the engine reaches a predetermined threshold speed. This preliminary timing ensures that engine speed reduction occurs only when necessary (at high speeds), preventing noise and load during shifts while maintaining engine stability by avoiding premature speed reduction that could cause stalling
2Ease of operation
If shift interrupt control strategies are invoked immediately, then gear shift smoothness is improved, but engine speed may drop too low causing instability
Solution Approach 1:
The control circuit continuously monitors engine speed and uses this feedback to determine the appropriate timing for invoking shift interrupt control strategies. By comparing real-time engine speed against a predetermined threshold, the system ensures that speed reduction occurs only when engine speed is sufficiently high, thereby achieving smooth gear shifts without causing engine instability or stalling
Data Source
AI summary
Systems and methods are for facilitating shift changes in a marine propulsion device. The systems comprise an internal combustion engine; a shift linkage that operatively connects a shift lever to a transmission for effecting shift changes amongst a reverse gear, a neutral gear and a forward gear; a speed sensor that senses current speed of the engine; and a control circuit that controls the engine to provide a reduction in speed of the engine to facilitate a shift change. The control circuit compares the current speed of the engine to a stored threshold speed and waits to invoke a reduction in speed of the engine until the current speed of the engine reaches the stored threshold speed.