Segmented Spiral Coil for Contactless Power Transmission

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Solution Overview

Problem

Existing contactless power transmission systems face challenges in efficiently transmitting power between coils of different diameters, leading to increased size and thickness issues due to the need for multiple coils or complex winding configurations.

Innovation Solution

A coil design featuring a first winding and a second winding, where both windings are wound in a spiral manner with equal thickness in crossing and non-crossing portions, allowing for adjustable diameter and reduced thickness, enabling efficient power transmission across varying device sizes without unnecessary space.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If multiple coils are arranged side by side in the transmitter to adapt to receivers of different coil diameters, then adaptability is improved, but the transmitter size increases

Engineering Contradiction:
Improveadaptability to different coil diametersVSAvoidtransmitter size
Core Design Contradiction:
Adaptability or versatilityVSArea of stationary object

Solution Approach 1:

The coil is divided into multiple independent winding sections (first winding section, second winding section, third winding section) that can be independently configured. Each section has its own inner circumferential side and outer circumferential side, allowing selective activation based on the receiver's coil diameter, thus providing adaptability without requiring multiple complete coils

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The windings are arranged in a nested configuration where the second winding section is positioned between the first and third winding sections in the axial direction. This nested structure allows multiple winding sections to share the same spatial envelope, reducing the overall transmitter size while maintaining the capability to adapt to different coil diameters

Inventive Principle:
Principle #7Nested doll (Nesting)

2Ease of manufacture

If the other side of the winding wire is drawn forth from the inner circumferential side onto the coil flat surface by the usual winding method, then the winding process is simplified, but the drawing line portion increases in thickness by the winding wire diameter

Engineering Contradiction:
Improvewinding process simplicityVSAvoidthickness uniformity
Core Design Contradiction:
Ease of manufactureVSShape

Solution Approach 1:

Instead of drawing the other side of the winding wire directly onto the coil flat surface (conventional method), the patent inverts the approach by guiding the other side to the outer circumferential side of the same winding section. This reversal eliminates the thickness increase problem while maintaining manufacturing simplicity

Inventive Principle:
Principle #13The other way round (Inversion)

Solution Approach 2:

The patent introduces an intermediary path for the winding wire by using the outer circumferential side of the same winding section as an intermediate destination. This intermediary approach allows the wire to be drawn forth without directly crossing over the coil flat surface, thereby avoiding the thickness increase that would result from such direct crossing

Inventive Principle:
Principle #24Intermediary (Mediator)

3Area of stationary object

If a large-diameter coil and a small-diameter coil are piled up on the same shaft, then the space in the coil diameter direction is reduced, but a larger space is required in the direction of the winding shaft axis

Engineering Contradiction:
Improvespace in coil diameter directionVSAvoidspace in winding shaft axis direction
Core Design Contradiction:
Area of stationary objectVSLength of moving object

Solution Approach 1:

The patent transitions from a radial arrangement (side-by-side coils) to an axial arrangement (piled-up windings). By organizing the first, second, and third winding sections along the axial direction rather than radially, the design reduces the coil diameter direction space while managing the axial space requirement through compact winding section configuration

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

4Stability of the object's composition

If the one side and the other side of the winding wire are drawn forth to the outer circumferential side without applying unnecessary force (α winding method), then the winding structure is improved, but the winding process becomes more complex

Engineering Contradiction:
Improvewinding structureVSAvoidwinding process complexity
Core Design Contradiction:
Stability of the object's compositionVSEase of manufacture

Solution Approach 1:

The coil is segmented into multiple independent winding sections, each capable of being wound using the α winding method. This segmentation allows the complex α winding technique to be applied to individual sections rather than the entire coil, making the manufacturing process more manageable while maintaining the structural benefits of the α winding method

Inventive Principle:
Principle #1Segmentation

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

The coil design allows for flexible diameter adjustment and reduced thickness, enhancing power transmission efficiency while minimizing space requirements, accommodating different device sizes with a single coil configuration.

Implementation Method 1

contactless power transmission designed so that power exchange is performed in a contactless (contact-free) manner by electromagnetic coupling of a coil in a transmitter and a coil in a receiver

Methodology Applied
Scientific EffectElectromagnetic coupling: Electromagnetic Induction

Data Source

PatentEP2413335B1Coil
Publication Date: 2021.06.30 SUMIDA CORP
  • EP2413335B1 patent drawingFigure 1
  • EP2413335B1 patent drawingFigure 2
  • EP2413335B1 patent drawingFigure 3

AI summary

A coil is formed by coaxially winding a second winding so as to be in intimate contact with an outer circumferential portion of a first winding wound about a winding shaft axis, In the first winding, one side of a winding wire is wound from an inner circumferential side to an outer circumferential side, the other side of the winding wire is drawn forth from the inner circumferential side to the outer circumferential side, while crossing the one side of the winding wire, and a thickness in a direction of the winding shaft axis in crossing portions of the one side of the winding wire and the other side of the winding wire is equal to a thickness in other portions.