Idling Stop Control via Latch Circuit for Battery Voltage Stability

Solution Overview

Problem

The idling stop function in vehicles can cause battery voltage to drop excessively, leading to engine automatic stop and further voltage reduction, as the microcomputer responsible for this function resets and loses voltage data, enabling unnecessary engine stops even when the battery voltage is low.

Innovation Solution

A configuration where the microcomputer monitors battery voltage and disables the idling stop function when it falls below a threshold, using a latch circuit to store reset information and prevent re-enabling until the ignition switch is turned off, ensuring stable operation and preventing battery voltage drops.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the microcomputer monitors battery voltage and disables the idling stop function when voltage falls below a threshold, then battery voltage stability is improved, but the system complexity increases due to additional monitoring and control logic

Engineering Contradiction:

Improvebattery voltage stabilityVSAvoidsystem complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The microcomputer performs preliminary monitoring of battery voltage and predicts potential voltage drops before they occur. When voltage approaches the threshold, the system proactively disables the idling stop function in advance, preventing the voltage drop from occurring rather than reacting after it happens. This is implemented through continuous voltage monitoring and predictive control logic that anticipates battery stress conditions.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system establishes a feedback loop where the microcomputer continuously monitors battery voltage and adjusts the idling stop function accordingly. When voltage falls below the predetermined threshold, the microcomputer receives feedback about the low voltage condition and automatically disables the idling stop function. This closed-loop control ensures voltage stability while maintaining system simplicity through automated response.

Inventive Principle:

Principle #23Feedback

2Reliability

If the microcomputer is reset due to low voltage, then the microcomputer restarts operation, but the idling stop function is incorrectly enabled causing further battery voltage reduction

Engineering Contradiction:

Improvemicrocomputer operation continuityVSAvoidbattery voltage reduction

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The microcomputer performs preliminary monitoring of battery voltage and predicts potential voltage drops before they occur. When voltage approaches the threshold, the system proactively disables the idling stop function in advance, preventing the voltage drop from occurring rather than reacting after it happens. This is implemented through continuous voltage monitoring and predictive control logic that anticipates battery stress conditions.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system establishes a feedback loop where the microcomputer continuously monitors battery voltage and adjusts the idling stop function accordingly. When voltage falls below the predetermined threshold, the microcomputer receives feedback about the low voltage condition and automatically disables the idling stop function. This closed-loop control ensures voltage stability while maintaining system simplicity through automated response.

Inventive Principle:

Principle #23Feedback

3Reliability

If the idling stop function is disabled to prevent battery voltage drop, then battery health is improved, but vehicle fuel saving opportunity is lost

Engineering Contradiction:

Improvebattery healthVSAvoidfuel saving opportunity

Core Design Contradiction:

ReliabilityVSLoss of energy

Solution Approach 1:

The microcomputer performs preliminary monitoring of battery voltage and predicts potential voltage drops before they occur. When voltage approaches the threshold, the system proactively disables the idling stop function in advance, preventing the voltage drop from occurring rather than reacting after it happens. This is implemented through continuous voltage monitoring and predictive control logic that anticipates battery stress conditions.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The system establishes a feedback loop where the microcomputer continuously monitors battery voltage and adjusts the idling stop function accordingly. When voltage falls below the predetermined threshold, the microcomputer receives feedback about the low voltage condition and automatically disables the idling stop function. This closed-loop control ensures voltage stability while maintaining system simplicity through automated response.

Inventive Principle:

Principle #23Feedback

Data Source

PatentEP2481904B1Method for inhibiting the idling stop in case of reset and apparatus thereof

Publication Date: 2023.09.06 FUJITSU TEN LTD

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AI summary

An idling stop apparatus is provided which can prevent a voltage of a battery from being lowered even when a microcomputer is reset. In an idling stop apparatus 1a, when a reset condition is established, reset information indicating that the reset condition is established is stored in a latch circuit 3a, and a microcomputer 2 disables an idling stop function when the reset information is stored. The reset information is stored in the latch circuit 3a even when the microcomputer 2 is being reset or even after the microcomputer is reset. Accordingly, the microcomputer 2 after the reset can disable the idling stop function. As a result, it is possible to prevent the voltage of the battery 51 from being lowered due to the idling stop function.