Idling Speed Control via Torque Ratio Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current idling rotation speed control systems for outboard engines require extensive man-hours and specific data settings for each engine, making them costly and labor-intensive, especially for trolling cruises where load conditions change frequently, and are complicated due to variations in engine capacity and load.
Innovation Solution
An idling rotation speed control apparatus that includes engine-rotation-speed detection, engine-temperature detection, idling driving state detection, load detection, and an ECU with basic torque ratio calculation, target torque ratio calculation, and intake air amount adjustment functions to control engine speed based on detected states, allowing for universal data usage and simplified control logic.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If direct feedback control of air amount is implemented based on rotation speed difference, then rotation speed control accuracy is improved, but control program complexity increases
Solution Approach 1:
The patent changes the control parameter from direct air amount feedback to torque ratio feedback. The ECU calculates a basic torque ratio from maps based on detected parameters (rotation speed, throttle opening, intake air temperature, engine load), then feeds back this torque ratio to control the air amount. This parameter transformation simplifies the control logic while maintaining accuracy.
Solution Approach 2:
The patent pre-calculates and stores basic torque ratio values in maps during the design phase, based on engine characteristics. These pre-computed maps contain the optimal torque ratios for various operating conditions. During operation, the ECU simply looks up the appropriate torque ratio from the maps based on current sensor readings, eliminating the need for complex real-time calculations.
2Adaptability or versatility
If extensive setting data is stored for each engine specification and load condition, then control accuracy across different conditions is improved, but development man-hours and data preparation time increase
Solution Approach 1:
The patent creates a universal control system that can accommodate different engine specifications and load conditions without requiring separate setting data for each case. The basic torque ratio maps are designed to be universally applicable across various engine types and configurations. The system adapts to different conditions through the detection means and map lookup mechanism rather than requiring dedicated settings for each scenario.
Solution Approach 2:
Instead of storing extensive setting data for each specific engine specification and load condition, the patent transforms the approach by using detection parameters (rotation speed, throttle opening, temperature, load) to dynamically select appropriate torque ratios from generalized maps. This parameter-based selection method reduces the volume of required setting data while maintaining adaptability across different engine configurations.
3Measurement precision
If minute throttle operation is required for trolling cruise control, then precise speed control is achieved, but operator burden increases especially during boat pitching and rolling
Solution Approach 1:
The patent implements automatic feedback control where the ECU continuously monitors the engine rotation speed and compares it with the target speed. Based on the detected deviation, the system automatically adjusts the air amount (and thus the throttle) to maintain the target speed. This automatic feedback mechanism eliminates the need for the operator to perform minute manual throttle adjustments, significantly reducing operator burden during trolling cruise even under pitching and rolling conditions.
Solution Approach 2:
The control system performs self-adjustment by automatically modifying the air supply based on detected rotation speed deviations. The ECU acts autonomously to maintain the target speed without requiring continuous manual intervention. The system serves itself by using its own sensors and actuators to correct any speed deviations, freeing the operator from the tedious task of minute throttle control.
Data Source
AI summary
There is provided an idling rotation speed control apparatus that can reduce the development man-hours and the cost and that enables operation during a trolling cruise to be readily performed. The idling rotation speed control apparatus includes an engine rotation speed detection means, an engine temperature detection means, an engine idling driving state detection means, an engine load detection means, an intake air amount adjusting means for adjusting an amount of intake air during an idling state, and an ECU for controlling the intake air amount adjusting means during idling driving. The ECU includes a basic torque ratio calculation function for calculating a ratio of torque to be generated, to engine maximal torque, that is necessary for making the engine steadily operate at a target rotation speed during idling driving; a target torque ratio calculation function for correcting the basic torque ratio, in accordance with a difference between a target rotation speed and an engine rotation speed, and calculating a target torque ratio; a target air amount calculation function for calculating an air amount necessary for generating the target torque ratio; and an intake air amount adjusting function for controlling the intake air amount adjusting means, based on the calculated air amount.