Tire Curing Mold with Induction Heating and Phase Change Material

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current tire curing methods face issues such as incomplete and asymmetric bladder structures leading to uneven mass distribution, energy inefficiency due to steam or water usage, inability to control temperature and pressure individually, and uneven heating causing performance degradation in tires.

Innovation Solution

A direct-pressure shaping method using a metal inner mold with a telescoping mechanism and electromagnetic induction heating, where the mold segments expand and contract to fit the tire shape, and electromagnetic coils generate eddy currents for precise temperature control, utilizing phase change materials to manage heat distribution.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If steam or superheated water is used for curing, then heat transfer efficiency is improved, but energy consumption increases significantly due to invalid pipeline loops

Engineering Contradiction:

Improveheat transfer efficiencyVSAvoidenergy waste in pipeline loops

Core Design Contradiction:

Use of energy by moving objectVSLoss of energy

Solution Approach 1:

The patent replaces the traditional steam-based heating system with an electromagnetic induction heating system. The electromagnetic heating device generates eddy currents directly in the tire, converting electromagnetic energy into heat without requiring thermal medium circulation through pipelines. This substitution eliminates energy waste in pipeline loops while maintaining efficient heat transfer.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The electromagnetic induction heating system allows the tire to heat itself through induced eddy currents. The heating energy is generated within the tire structure itself rather than being transferred from an external thermal medium, eliminating the need for extensive heating pipelines and reducing energy loss in the heating system.

Inventive Principle:

Principle #25Self-service

2Stress or pressure

If steam curing is used with suitable curing pressure, then pressure control is achieved, but curing temperature is low and curing time must be prolonged

Engineering Contradiction:

Improvecuring pressureVSAvoidcuring temperature

Core Design Contradiction:

Stress or pressureVSTemperature

Solution Approach 1:

The patent employs electromagnetic induction heating to independently control the temperature parameter during curing. By adjusting the electromagnetic power and frequency, the system can achieve high curing temperatures (typically 140-180°C) while maintaining appropriate curing pressure (0.3-0.6 MPa), eliminating the temperature-pressure coupling limitation of steam curing.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The electromagnetic induction heating uses alternating current at specific frequencies (typically 20-100 kHz) to generate eddy currents in the tire. This periodic electromagnetic action efficiently converts electrical energy to thermal energy, enabling rapid and uniform temperature rise throughout the tire structure during curing.

Inventive Principle:

Principle #19Periodic action

3Temperature

If steam in the bladder transfers heat uniformly to the whole green tire, then heating coverage is improved, but shoulder and bead areas are overcured when crown and sidewall reach optimal temperature

Engineering Contradiction:

Improveheating coverageVSAvoidcuring uniformity

Core Design Contradiction:

TemperatureVSManufacturing precision

Solution Approach 1:

The electromagnetic induction heating system enables localized temperature control by adjusting the distribution and intensity of electromagnetic coils. Different regions of the tire (shoulder, bead, crown, sidewall) can receive different heating intensities, allowing each area to reach its optimal curing temperature simultaneously without overcuring any specific region.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

Replacing the uniform steam heating mechanism with electromagnetic induction heating allows for precise spatial and temporal control of heat input. The electromagnetic field can be selectively applied to different tire regions, enabling differentiated heating patterns that match the specific curing requirements of each tire area.

Inventive Principle:

Principle #28Mechanics substitution (Replace mechanical system)

4Adaptability or versatility

If flexible bladder is used for shaping, then adaptability to tire shape is improved, but mass distribution becomes uneven due to incomplete or asymmetric bladder structure

Engineering Contradiction:

Improvebladder adaptabilityVSAvoidmass distribution uniformity

Core Design Contradiction:

Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The inner mold is divided into multiple rigid segments that can be independently adjusted and positioned. This segmentation allows precise control of each mold segment to ensure symmetric and complete closure, eliminating the deformation and asymmetry issues associated with flexible bladders while maintaining adaptability to tire geometry.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Instead of using a flexible bladder that deforms under pressure, the patent employs rigid mold segments that actively shape the tire through controlled expansion. This inversion of the shaping mechanism provides better structural integrity and more uniform mass distribution while achieving the required adaptability.

Inventive Principle:

Principle #13The other way round (Inversion)

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 method achieves uniform tire distribution, reduces energy consumption, allows individual control of temperature and pressure, and ensures consistent heating across tire parts, improving tire balance, uniformity, and performance.

Implementation Method 1

electromagnetic induction heating

Methodology Applied

Scientific EffectElectromagnetic induction: Electromagnetic Induction

Implementation Method 2

electromagnetic coils generate eddy currents for precise temperature control

Methodology Applied

Scientific EffectEddy currents: Eddy Currents

Implementation Method 3

utilizing phase change materials to manage heat distribution

Methodology Applied

Scientific EffectPhase change: Phase Change

Data Source

PatentUS9827725B2Tire direct-pressure shaping and electromagnetic induction heating curing method and apparatus

Publication Date: 2017.11.28 TRIANGLE TIRE

AI summary

A tire direct-pressure shaping and electromagnetic induction heating curing method uses an inner metal mold including large and small segments, a telescoping mechanism, supporting plates attached to the segments, and induction heating coils. A cavity in the middle of the segments is filled of phase change material. The temperature of the mold rises rapidly by the thermal effect of an eddy current generated on the surface of the segments to heat the green tire. When the middle part of the segment is heated to a certain temperature, the phase change material absorbs and stores the excess heat. Therefore, the temperature of the middle part of the segment differs from one of two ends of the segment. Once the tire is cured, the inner mold in the expanded condition and the outer mold support very high pressure for the green tire together.