Non-Uniform Cellular Knee Padding for Even Pressure Distribution

Solution Overview

Problem

Existing protective equipment, such as knee pads, often suffer from uneven pressure distribution and high pressure zones, leading to discomfort and potential damage to the wearer's knees, while conventional padding materials are bulky and inefficient in load deflection.

Innovation Solution

A knee pad design featuring a single, integral padding layer with a cellular structure and non-uniform cell sizes and angles, optimized through a packing algorithm to distribute pressure evenly and minimize high-pressure zones, using a thinner polymer material with a zig-zag cell profile.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If conventional padding materials are used, then protection is provided, but the padding becomes bulky and creates high pressure zones

Engineering Contradiction:

Improveprotection capabilityVSAvoidpadding thickness

Core Design Contradiction:

StrengthVSVolume of moving object

Solution Approach 1:

The patent employs a foam material with a cellular structure containing numerous cells with varying sizes and shapes. This porous structure allows the padding to provide adequate protection through energy absorption while reducing overall material volume and eliminating bulky characteristics. The cells collapse progressively under load, distributing pressure evenly without creating high-pressure zones.

Inventive Principle:

Principle #31Porous materials

Solution Approach 2:

The foam material features non-uniform cell structure where cell sizes, shapes, and densities vary throughout the padding layer. This local variation in material properties allows different regions to provide appropriate protection levels while maintaining overall compactness. Areas requiring higher protection have denser or larger cells, while other areas use lighter structures.

Inventive Principle:

Principle #3Local quality

2Strength

If conventional padding materials are used, then protection is provided, but uneven pressure distribution and high pressure zones occur

Engineering Contradiction:

Improveprotection capabilityVSAvoidcomfort and pressure distribution

Core Design Contradiction:

StrengthVSEase of operation

Solution Approach 1:

The foam material features non-uniform cell structure where cell sizes, shapes, and densities vary throughout the padding layer. This local variation in material properties allows different regions to provide appropriate protection levels while maintaining overall compactness. Areas requiring higher protection have denser or larger cells, while other areas use lighter structures.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent varies key parameters of the foam structure including cell size, cell shape, cell density, and wall thickness throughout the padding material. These parameter changes enable the padding to adapt to different pressure requirements across the contact surface, distributing loads evenly and preventing high-pressure zones that cause discomfort.

Inventive Principle:

Principle #35Parameter changes

3Strength

If thicker padding material is used, then protection is improved, but the equipment becomes bulkier and less efficient

Engineering Contradiction:

Improveprotection capabilityVSAvoidequipment bulk and efficiency

Core Design Contradiction:

StrengthVSDevice complexity

Solution Approach 1:

The patent employs a foam material with a cellular structure containing numerous cells with varying sizes and shapes. This porous structure allows the padding to provide adequate protection through energy absorption while reducing overall material volume and eliminating bulky characteristics. The cells collapse progressively under load, distributing pressure evenly without creating high-pressure zones.

Inventive Principle:

Principle #31Porous materials

Solution Approach 2:

The foam material represents a composite structure combining polymer matrix with gas-filled cells, creating a material with superior protection-to-volume ratio. The cellular architecture provides both mechanical protection and compactness, eliminating the need for thick solid material layers.

Inventive Principle:

Principle #40Composite 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

The design achieves a relatively linear load deflection response, reducing thickness and pressure concentration, enhancing comfort and protection by distributing pressure more evenly across the knee pad.

Implementation Method 1

Each of the plurality of cells includes a channel connecting the outer surface and the inner surface, a longitudinal axis extending along the channel, and a cell wall enclosing the channel. The cell wall includes a plurality of segments angled relative the longitudinal axis.

Methodology Applied

Scientific EffectElastic deformation: Elasticity

Implementation Method 2

The padding layer includes an outer surface that interfaces against the shell, an inner surface, and a plurality of cells. Each of the plurality of cells extends between the outer surface and the inner surface.

Methodology Applied

Scientific EffectEnergy absorption through cell collapse: Compression

Data Source

PatentUS20250221476A1Padding Material for Protective Equipment

Publication Date: 2025.07.10 MILWAUKEE ELECTRIC TOOL CORP

AI summary

A padding material for protective equipment is provided. The padding material is formed from a single, integral piece of material with a cellular structure. The size and/or shape of the cellular structure is non-uniform to provide support and reduce pressure in chosen areas. One embodiment of the protective equipment includes knee pad with a shell, padding disposed in front of the knee of the wearer, the padding including a non-uniform stiffness.