Battery Charger Fan Control via Segmented Circuits

Solution Overview

Problem

Existing battery chargers face challenges in efficiently controlling the charging of multiple battery packs with a single control circuit, leading to inefficiencies in cooling and heat management for voltage conversion circuits.

Innovation Solution

A battery charger design that includes separate control circuits for each battery pack, with a single fan controlled by both circuits to efficiently cool multiple converters, using drive signals and non-rotation detection to manage fan operation and prevent overheating.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If a single control circuit is used to control charging of multiple battery packs, then device complexity is reduced, but charging control efficiency deteriorates

Engineering Contradiction:

Improvecontrol circuit configurationVSAvoidcharging control efficiency

Core Design Contradiction:

Device complexityVSProductivity

Solution Approach 1:

The control system is segmented into multiple independent control circuits, with each control circuit dedicated to controlling the charging of a specific battery pack. This segmentation allows each control circuit to independently manage its assigned battery pack's charging process, improving control efficiency while keeping each individual control circuit relatively simple in structure.

Inventive Principle:

Principle #1Segmentation

2Device complexity

If a single fan is used to cool multiple converters, then device complexity is reduced, but cooling effectiveness deteriorates

Engineering Contradiction:

Improvecooling system configurationVSAvoidconverter heat management

Core Design Contradiction:

Device complexityVSTemperature

Solution Approach 1:

The single fan is designed to perform multiple cooling functions simultaneously by directing airflow to multiple converters. The fan serves as a universal cooling component that can cool different converters based on their respective thermal conditions, reducing the total number of fans while maintaining effective heat dissipation across all converters through intelligent airflow distribution.

Inventive Principle:

Principle #6Universality (Multi-functionality)

3Productivity

If individual control circuits are provided for each battery pack, then charging control efficiency is improved, but device complexity increases

Engineering Contradiction:

Improvecharging control efficiencyVSAvoidcontrol circuit configuration

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The control system is segmented into multiple independent control circuits, with each control circuit dedicated to controlling the charging of a specific battery pack. This segmentation allows each control circuit to independently manage its assigned battery pack's charging process, improving control efficiency while keeping each individual control circuit relatively simple in structure.

Inventive Principle:

Principle #1Segmentation

4Temperature

If multiple fans are used to cool multiple converters, then cooling effectiveness is improved, but device complexity increases

Engineering Contradiction:

Improveconverter heat managementVSAvoidcooling system configuration

Core Design Contradiction:

TemperatureVSDevice complexity

Solution Approach 1:

The single fan is designed to perform multiple cooling functions simultaneously by directing airflow to multiple converters. The fan serves as a universal cooling component that can cool different converters based on their respective thermal conditions, reducing the total number of fans while maintaining effective heat dissipation across all converters through intelligent airflow distribution.

Inventive Principle:

Principle #6Universality (Multi-functionality)

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 allows for efficient control of a single fan to cool multiple converters, simplifying the control circuit configuration and effectively managing heat generation during charging, thereby preventing overheating and ensuring reliable operation.

Implementation Method 1

The fan feeds a cooling air flow (or air flow or cooling air) to both the first converter and the second converter in response to receiving a drive signal. The cooling air flow can cool the first converter and/or the second converter. Alternatively, the cooling air flow can suppress heat generation of the first converter and/or the second convener.

Methodology Applied

Scientific EffectForced Convection: Forced Convection

Data Source

PatentUS11721987B2Technique for driving fan of battery charger

Publication Date: 2023.08.08 MAKITA CORP

AI summary

A battery charger in one aspect of the present disclosure includes a first attachment portion, a second attachment portion, a first converter, a second converter, a fan, a first control circuit, a second control circuit, and a signal output circuit. The first control circuit (i) controls the first converter and (ii) transmits a command to drive the fan in response to a first drive condition being fulfilled. The second control circuit (i) controls the second converter and (ii) transmits a command to drive the fan in response to a second drive condition being fulfilled. The signal output circuit outputs a drive signal in response to the first control circuit and/or the second control circuit transmitting the command(s) to drive the fan. The fan feeds a cooling air flow to the first convertor and the second converter in response to receiving the drive signal.