Direct-Molded Motorcycle Helmet Shell and Liner

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Solution Overview

Problem

Conventional motorcycle helmets face issues with weight, ventilation, and structural integrity due to separate manufacturing processes for the outer shell and impact liner, leading to increased weight, potential overheating, and limitations in ventilation design that compromise impact absorption.

Innovation Solution

The direct molding of the impact liner to the outer shell eliminates separate production steps, reduces weight, and integrates larger, more efficient ventilation tunnels within the shell, forming a unitary structure that enhances both safety and airflow.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If the outer shell and impact liner are manufactured separately and then assembled, then the manufacturing process is simpler and more flexible, but the helmet weight increases and structural integrity decreases

Engineering Contradiction:
Improvemanufacturing process flexibilityVSAvoidhelmet weight
Core Design Contradiction:
Ease of manufactureVSWeight of moving object

Solution Approach 1:

The patent merges the outer shell and impact liner into a single integrated component manufactured through one-piece molding. This eliminates the need for separate manufacturing and assembly processes, reducing the number of parts and connection interfaces while maintaining manufacturing simplicity through a unified molding operation.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The integrated helmet structure performs multiple functions simultaneously: the outer shell provides protective rigidity while the integrated impact liner provides shock absorption, all within a single molded component. This multi-functional design eliminates the need for separate assembly of protective and energy-absorbing elements.

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

2Adaptability or versatility

If the outer shell and impact liner are manufactured separately and then assembled, then each component can be optimized independently, but structural integrity and strength decrease

Engineering Contradiction:
Improvecomponent optimization flexibilityVSAvoidstructural integrity
Core Design Contradiction:
Adaptability or versatilityVSStrength

Solution Approach 1:

The patent combines the outer shell and impact liner into a single molded structure, eliminating weak interfaces between separate components. The integration ensures continuous material flow and structural continuity, maximizing strength while allowing design optimization of the entire system as a unified structure.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The integrated helmet utilizes composite material construction where the outer shell and impact liner are formed as one piece using composite molding techniques. This allows the material composition to be optimized for both protective rigidity and shock absorption properties simultaneously, maintaining adaptability in material selection while achieving superior structural integrity.

Inventive Principle:
Principle #40Composite materials

3Strength

If conventional EPS foam is used for the impact liner, then impact absorption is excellent and the material is lightweight, but thermal insulation causes wearer overheating

Engineering Contradiction:
Improveimpact absorption capabilityVSAvoidwearer head temperature
Core Design Contradiction:
StrengthVSTemperature

Solution Approach 1:

The patent employs a porous or cellular structure within the impact liner that maintains the shock-absorbing characteristics of foam materials while creating channels for air circulation. This porous architecture allows thermal management by facilitating heat dissipation and air flow, reducing wearer overheating while preserving impact protection.

Inventive Principle:
Principle #31Porous materials

Solution Approach 2:

The integrated helmet design allows different regions of the impact liner to have different properties: areas requiring maximum impact absorption maintain dense foam structure, while regions near ventilation openings or contact points utilize more open cellular structures for thermal management. This local variation optimizes both protection and comfort.

Inventive Principle:
Principle #3Local quality

4Temperature

If ventilation channels are added to the impact liner to improve airflow, then cooling is enhanced, but the structural integrity and impact absorption capability are compromised

Engineering Contradiction:
Improvewearer cooling efficiencyVSAvoidimpact absorption capability
Core Design Contradiction:
TemperatureVSStrength

Solution Approach 1:

The patent integrates ventilation channels directly into the molding process of the impact liner, combining the structural formation with the creation of airflow pathways. This ensures that the channels are structurally sound and do not create weak points, as the entire structure including channels is formed as one piece with optimized material distribution.

Inventive Principle:
Principle #5Merging (Combining)

Solution Approach 2:

The ventilation system utilizes the porous cellular structure of the impact liner material itself to provide airflow pathways, rather than introducing large separate channels. The natural cell structure of the foam material creates micro-ventilation paths that maintain structural integrity while enabling thermal management through air circulation.

Inventive Principle:
Principle #31Porous materials

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 approach results in a lighter, safer, and more comfortable helmet with improved ventilation and structural reinforcement, reducing production time and costs while eliminating air gaps for better safety and performance.

Implementation Method 1

Heat is introduced into the mold to activate the resin

Methodology Applied
Scientific EffectHeat activation: Heat Treatment

Implementation Method 2

the bladder is inflated with sufficient pressure to force the composite sheet material into the shape of the mold

Methodology Applied
Scientific EffectPressure: Pressure Increase

Implementation Method 3

an inner liner of an impact absorbing material

Methodology Applied
Scientific EffectImpact absorption: Impact Force

Implementation Method 4

the impact liner material, which is typically EPS

Methodology Applied
Scientific EffectCompression: Compression

Implementation Method 5

the impact liners, such as EPS foam and similar material are highly thermally insulating, like a Styrofoam cup

Methodology Applied
Scientific EffectThermal insulation: Thermal Insulation

Data Source

PatentEP2289360B1Molded motorcycle helmet and method of manufacture
Publication Date: 2016.12.07 FOX HEAD INC
  • EP2289360B1 patent drawingFigure 1
  • EP2289360B1 patent drawingFigure 2~4
  • EP2289360B1 patent drawingFigure 5~6

AI summary

Protective structures, such as helmets, and methods for molding the same. In certain respects, one or more tunnels are formed in or integral to an outer shell for a helmet to provide ventilation, for example. In other respects, an impact liner materials, such as EPS, may be directly in-molded to shells suitable for use in motorcycle helmets and other helmets that must meet certain standards. The impact liner may include one or more venting channels that are coupled to a tunnel integral to the shell structure.