Ironless Laminated Sheet Winding for High Density Motor Design

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional iron-cored motors are heavy and inefficient due to low packing densities and increased air gaps when coils are stacked, which is a concern for applications like aircraft where weight is critical, and they do not allow for efficient use of magnetic flux.

Innovation Solution

The development of an ironless core radial flux motor system using laminated sheet windings made from conductive materials like aluminum or copper, where stacked sheets are electrically connected in series to create a dense, thin conductor area with minimal air gaps, allowing for efficient magnetic flux interaction and reduced weight.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If conventional iron-cored windings are used, then motors can be powerful and efficient, but the motors become heavy and have poor packing density

Engineering Contradiction:
Improvemotor powerVSAvoidmotor weight
Core Design Contradiction:
PowerVSWeight of moving object

Solution Approach 1:

The patent removes the iron core from the motor winding structure, extracting the harmful weight component while maintaining the conductive path for magnetic flux interaction. The ironless core design eliminates the heavy ferromagnetic material that traditionally provided magnetic path continuity, replacing it with a lightweight alternative that achieves similar magnetic coupling through direct conductor exposure.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent employs composite construction by stacking multiple thin conductive sheets (such as aluminum or copper) to form the winding structure. These sheets are arranged and connected to create both mechanical strength and electrical continuity without requiring a solid iron core, achieving a composite material solution that balances structural integrity with weight reduction.

Inventive Principle:
Principle #40Composite materials

2Productivity

If coils are stacked together in conventional motors, then windings can be formed, but air gaps increase and packing density decreases

Engineering Contradiction:
Improvepacking densityVSAvoidmagnetic flux efficiency
Core Design Contradiction:
ProductivityVSLoss of energy

Solution Approach 1:

The patent implements a nested stacking arrangement where multiple conductor sheets are positioned one over another with precise alignment, creating a compact layered structure. The conductive sheets are nested within the stator or rotor assembly such that they maximize the use of available space, minimizing air gaps between adjacent windings and improving the overall packing density of the magnetic circuit.

Inventive Principle:
Principle #7Nested doll (Nesting)

Solution Approach 2:

The patent transitions from traditional three-dimensional coil winding to a two-dimensional sheet stacking approach. By laying down thin conductive sheets in parallel layers rather than wrapping volumetric coils, the design achieves better space utilization and reduced air gaps in the radial and axial dimensions, effectively using dimensional reconfiguration to improve packing efficiency.

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

3Force

If iron-cored configurations are used, then motors produce sufficient torque, but rotational inertia increases and responsiveness decreases

Engineering Contradiction:
Improvetorque productionVSAvoidresponsiveness
Core Design Contradiction:
ForceVSSpeed

Solution Approach 1:

The patent extracts the heavy iron core that contributes to rotational inertia while maintaining the essential magnetic flux path through the use of stacked conductive sheets. By removing the ferromagnetic core material, the moment of inertia is significantly reduced, allowing the motor to accelerate and respond more quickly to control signals while still achieving adequate torque through the exposed conductor surfaces interacting with the magnetic field.

Inventive Principle:
Principle #2Taking out (Extraction)

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 design results in a more efficient, lightweight motor with improved packing density and reduced air gaps, enhancing torque production and extending the lifespan of slip rings, while also reducing rotational inertia and increasing responsiveness.

Implementation Method 1

The stacked sheets are electrically connected in series to create a winding

Methodology Applied
Scientific EffectElectrical conduction: Conduction (electrical)

Implementation Method 2

When rotated within a magnetic field or introduced to a rotating magnetic field, the resulting induction motor produces torque

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Data Source

PatentEP3116105B1Laminated sheet winding
Publication Date: 2019.04.24 THE BOEING CO
  • EP3116105B1 patent drawingFigure 1A~1D
  • EP3116105B1 patent drawingFigure 2A~2B
  • EP3116105B1 patent drawingFigure 2C~2D

AI summary

Apparatuses, systems, and methods provide for high density laminated sheet windings in axial and radial flux configurations. According to embodiments described herein, motor components such as a rotor or stator include a number of stacked sheets (114) of conductive material. The stacked sheets (114) are electrically connected in series to create a winding. Each motor component includes a number of conductors (108) spaced apart with apertures between. The motor components are stacked and configured with the conductors (108) of one rotor or stator positioned within the apertures (110) of the other rotor or stator to create a thin, high density conductor. A magnetomotive force is created when the magnetic flux is positioned over the conductors (108).