Wireless Power Feed Device Card Detection Control

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Solution Overview

Problem

Non-contact charging systems pose a risk of damaging IC cards or similar cards when they are present near portable electronic devices being charged, as they can be affected by electromagnetic waves used in the charging process.

Innovation Solution

A power feed device and power receiving device configuration that uses a magnetic field for charging, where a controller in the power feed device controls the generation of the magnetic field based on card detection information received from the power receiving device, preventing the field from being generated if a card is detected, thus avoiding damage to the card.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If electromagnetic waves are used for wireless charging, then power can be transmitted without contact, but cards near the charging area may be damaged by the electromagnetic waves

Engineering Contradiction:
Improvewireless charging capabilityVSAvoidcard damage from electromagnetic waves
Core Design Contradiction:
Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The system performs card detection before initiating power transmission. The power receiving device detects the presence of a card in its vicinity and communicates this information to the power feed device, which then decides whether to start charging. This preliminary detection prevents cards from being exposed to harmful electromagnetic waves.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The power receiving device continuously monitors the charging area for cards and provides feedback to the power feed device. Based on this feedback, the power feed device adjusts its operation - either preventing power transmission when a card is detected or allowing normal charging when no card is present. This closed-loop control resolves the contradiction by making power transmission conditional on card presence.

Inventive Principle:
Principle #23Feedback

2Object-affected harmful factors

If card detection is implemented to prevent card damage, then card safety is improved, but the device complexity increases due to additional detection and communication components

Engineering Contradiction:
Improvecard protection from damageVSAvoiddetection and communication system
Core Design Contradiction:
Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The power receiving device uses its existing communication coil and control circuitry for both power reception and card detection functions. The same coil that receives magnetic fields for charging also detects the presence of cards through impedance changes, eliminating the need for separate detection hardware. This multi-functionality approach reduces device complexity while maintaining card protection capabilities.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Solution Approach 2:

The power receiving device autonomously performs card detection and communicates the results to the power feed device without requiring additional external sensors or complex processing systems. The device uses its inherent electromagnetic characteristics to detect cards and makes independent decisions about charging safety, simplifying the overall system architecture.

Inventive Principle:
Principle #25Self-service

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

Effectively prevents damage to cards by ensuring that the magnetic field and subsequent power transfer are only initiated when no cards are near the charging area, thereby safeguarding them during the charging process.

Implementation Method 1

a coil configured to generate the magnetic field

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Implementation Method 2

the coil is configured to transmit a signal based on a resonant frequency of a card

Methodology Applied
Scientific EffectElectromagnetic resonance: Resonance

Data Source

PatentEP3288154B1Power feed device and power receiving device
Publication Date: 2019.01.02 FUNAI ELECTRIC CO LTD
  • EP3288154B1 patent drawingFigure 1~2A
  • EP3288154B1 patent drawingFigure 2B~3
  • EP3288154B1 patent drawingFigure 4

AI summary

A power feed device is configured to feed power to a power receiving device using a magnetic field. The power feed device includes a coil, a first communication component, and a controller. The coil is configured to generate the magnetic field. The first communication component is configured to communicate with the power receiving device. The controller is configured to control generation of the magnetic field based on a card information.