Brush Head Assembly Shear-Thickening Matrix Bristle Retention

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing brush head assemblies face challenges in retaining bristles securely while maintaining flexibility and conforming to the complex topography of teeth and gums, which affects plaque removal efficiency, particularly at the gum line and interproximal spaces.

Innovation Solution

The brush head assembly incorporates bristle tufts retained within a sandwich of flexible material between two layers of stiffer material or uses a shear-thickening material, with optional retention elements like rings or sleeves, to enhance retention and flexibility, allowing for better adaptation to tooth and gum surfaces.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If anchor-free tufting of bristles is used, then flexibility of bristles is improved, but bristle retention and positioning stability deteriorate

Engineering Contradiction:

Improveflexibility of bristlesVSAvoidbristle retention

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The bristle tufts are nested within a retention structure formed by the flexible matrix material. The matrix encapsulates the proximal ends of the bristles, creating a nested configuration where the bristles are retained within the material structure, preventing them from becoming loose while maintaining flexibility.

Inventive Principle:

Principle #7Nested doll (Nesting)

Solution Approach 2:

The invention uses a composite structure combining flexible matrix material with bristle tufts. The flexible matrix provides both retention through its structural encapsulation and flexibility through its material properties, creating a composite system that resolves the contradiction between retention and flexibility.

Inventive Principle:

Principle #40Composite materials

2Adaptability or versatility

If longer bristles are used, then ability to splay over tooth topography is improved, but brush head bulkiness and manoeuvrability deteriorate

Engineering Contradiction:

Improveability to splay over topographyVSAvoidbrush head bulkiness

Core Design Contradiction:

Adaptability or versatilityVSVolume of moving object

Solution Approach 1:

The flexible matrix acts as a flexible shell that allows the bristle tufts to splay and conform to tooth surfaces. This flexible encapsulation enables longer bristles to adapt to complex topography without requiring excessive brush head volume, as the flexibility is provided by the thin flexible matrix rather than bulkier rigid structures.

Inventive Principle:

Principle #30Flexible shells and thin films

3Adaptability or versatility

If elastomer material is used in brush head, then conformity to tooth surface is improved, but transmission of lateral forces deteriorates

Engineering Contradiction:

Improveconformity to tooth surfaceVSAvoidtransmission of lateral forces

Core Design Contradiction:

Adaptability or versatilityVSForce

Solution Approach 1:

The flexible matrix material creates a composite structure that combines the conformability of elastomeric materials with enhanced force transmission capabilities. The specific formulation and structural configuration of the flexible matrix enable it to provide both surface conformity and adequate lateral force transmission to the bristle tufts.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The invention modifies the physical parameters of the flexible matrix material to achieve optimal balance between conformity and force transmission. By adjusting material properties such as stiffness, density, and structural configuration, the flexible matrix can conform to tooth surfaces while maintaining sufficient rigidity to transmit lateral forces effectively.

Inventive Principle:

Principle #35Parameter changes

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 improves bristle retention and plaque removal efficiency by providing the necessary flexibility and conformity to tooth and gum topography, enabling effective sweeping of bristles across surfaces, even in hard-to-reach areas.

Implementation Method 1

a flexible matrix (30') at least partially comprised of a shear-thickening fluid bonded to and encompassing at least a portion of the hard platen, and the proximal end of the bristle tufts

Methodology Applied

Scientific EffectShear-thickening: Shear Thickening

Data Source

PatentUS11160361B2Brush head assembly

Publication Date: 2021.11.02 KONINKLIJKE PHILIPS NV

AI summary

A brush head assembly comprising: a hard platen; a plurality of bristle tufts, each of which comprises a plurality of bristle strands, each bristle tuft having a proximal end and a free end; and a flexible matrix at least partially comprised of a shear-thickening material for coupling the plurality of bristle tufts to the hard platen, wherein the flexible matrix is arranged such that there is shear-thickening material between the proximal ends of the plurality of bristle tufts and the hard platen. A method of manufacturing the brush head assembly for use with a personal care appliance.