Internally Cooled Magnetic Rotor to Prevent Heat-Driven Demagnetization

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Magnetic rotors used for heating substrates face issues with heat generation leading to reduced field strength, efficiency, and shortened lifespan due to demagnetization, as existing internally cooled rotor systems are not effectively designed to manage heat during operation.

Innovation Solution

A magnetic rotor system with a rotatable rotor body featuring a chamber for coolant flow, where a coolant supply is in fluid communication with the rotor body to remove heat from the magnets, maintaining magnetic field strength and extending the rotor's usable life by controlling temperature gradients.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Power

If a magnetic rotor with permanent magnets is used to heat a substrate, then heating capability is improved, but heat generated by the magnets reduces field strength and efficiency

Engineering Contradiction:
Improveheating capabilityVSAvoidfield strength
Core Design Contradiction:
PowerVSLoss of energy

Solution Approach 1:

The patent extracts the harmful heat generated by the magnets from the magnetic rotor system by introducing a separate coolant circulation system. The coolant absorbs excess heat from the rotor body and magnets, carrying it away to a heat exchanger, thereby maintaining magnetic field strength while preserving heating capability.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent introduces coolant as an intermediary substance between the heat-generating magnets and the surrounding environment. This intermediary absorbs thermal energy through convection and conduction, transferring it away from the magnetic components to prevent field strength degradation.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Power

If a magnetic rotor with permanent magnets is used to heat a substrate, then heating capability is improved, but the possibility of demagnetization increases

Engineering Contradiction:
Improveheating capabilityVSAvoiddemagnetization risk
Core Design Contradiction:
PowerVSReliability

Solution Approach 1:

The patent extracts harmful heat from the magnetic rotor by implementing an internal coolant circulation system with channels positioned near the magnets. This continuous heat removal prevents temperature from reaching demagnetization thresholds, thereby protecting magnetic properties while maintaining heating function.

Inventive Principle:
Principle #2Taking out (Extraction)

Solution Approach 2:

The patent applies prior cushioning by pre-cooling the rotor body and magnets through continuous coolant circulation before demagnetization can occur. The system proactively manages thermal buildup, creating a thermal buffer that prevents catastrophic demagnetization events.

Inventive Principle:
Principle #11Beforehand cushioning (Prior cushioning)

3Power

If a magnetic rotor with permanent magnets is used to heat a substrate, then heating capability is improved, but the useable life of the magnetic rotor is reduced

Engineering Contradiction:
Improveheating capabilityVSAvoidusable life
Core Design Contradiction:
PowerVSDuration of action of stationary object

Solution Approach 1:

The patent implements continuous cooling action through a circulation system that constantly moves coolant through channels in the rotor body. This uninterrupted thermal management prevents cumulative thermal damage, extending the operational lifespan of the magnetic rotor while maintaining heating capability.

Inventive Principle:
Principle #20Continuity of useful action

Solution Approach 2:

The patent extracts accumulated heat from the magnetic rotor through continuous coolant circulation and external heat exchange. By continuously removing thermal energy that would otherwise degrade materials and magnets over time, the system extends usable life while preserving heating power.

Inventive Principle:
Principle #2Taking out (Extraction)

4Temperature

If an internally cooled rotor system is used, then heat management is improved, but the system complexity increases

Engineering Contradiction:
Improveheat managementVSAvoidsystem complexity
Core Design Contradiction:
TemperatureVSDevice complexity

Solution Approach 1:

The patent merges the cooling function directly into the magnetic rotor structure by integrating coolant channels within the rotor body itself. This combination eliminates the need for separate external cooling apparatus, reducing overall system complexity while maintaining effective temperature control.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The patent applies nesting by placing coolant channels and flow paths inside the rotor body structure. The cooling system is nested within the magnetic rotor, allowing heat management functionality to be embedded without adding external complexity.

Inventive Principle:
Principle #7Nested doll (Nesting)

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 internally cooled magnetic rotor system effectively maintains magnetic field strength, increases operational efficiency, and extends the rotor's lifespan by efficiently managing heat, allowing for higher rotational speeds and the ability to heat thicker or more conductive substrates without premature demagnetization.

Implementation Method 1

The magnetic rotor rotates about an axis to induce a magnetic field into the substrate to heat the substrate

Methodology Applied
Scientific EffectElectromagnetic induction: Electromagnetic Induction

Implementation Method 2

The rotor body defines a coolant flow path within the chamber from the inlet to the outlet, and the rotor body is configured to receive a coolant within the chamber

Methodology Applied
Scientific EffectThermal conduction: Conduction (thermal)

Implementation Method 3

a coolant supply is in fluid communication with the magnetic rotor such that a coolant can be provided into the chamber of the rotor body

Methodology Applied
Scientific EffectConvection: Convection

Data Source

PatentEP4091237B1Internally cooled magnetic rotor for heating a substrate
Publication Date: 2023.12.13 NOVELIS INC(US)
  • EP4091237B1 patent drawingFigure 1
  • EP4091237B1 patent drawingFigure 2
  • EP4091237B1 patent drawingFigure 3

AI summary

Disclosed are magnetic rotors systems and methods for heating a substrate. The magnetic rotor includes a rotor body and at least one magnet supported on the rotor body. The rotor body is rotatable about an axis. The rotor body also defines a chamber that selectively receives a coolant within the chamber.