Power Toothbrush Eccentric Brushhead Design

Solution Overview

Problem

Existing power toothbrushes with multiple motions require additional mechanical linkages, increasing size, noise, wear, and assembly complexity, which detract from the brushing experience and increase costs.

Innovation Solution

A power toothbrush with a brushhead assembly featuring a primary oscillating motion and a secondary spinning motion achieved through an eccentric bristle field mounted on a bristle base plate, eliminating the need for separate mechanical linkages by using a single drive assembly to impart both motions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If additional mechanical linkages are used to create secondary motion, then multiple motion oral care is achieved, but device size increases

Engineering Contradiction:

Improvemultiple motion oral careVSAvoidbrushhead assembly size

Core Design Contradiction:

Adaptability or versatilityVSVolume of moving object

Solution Approach 1:

The patent combines the drive mechanisms for primary and secondary motions into a single integrated drive assembly. The drive assembly includes an eccentric mechanism that generates both the oscillating primary motion of the brush member and the spinning secondary motion of the secondary bristle field, eliminating the need for separate mechanical linkages and reducing brushhead size.

Inventive Principle:

Principle #5Merging (Combining)

Solution Approach 2:

The drive assembly serves multiple functions simultaneously: it generates the primary oscillating motion, creates the secondary spinning motion through its eccentric mechanism, and transmits both motions to the appropriate brush fields. This multi-functionality eliminates the need for separate dedicated mechanisms for each motion type.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Adaptability or versatility

If additional mechanical linkages are used to create secondary motion, then multiple motion oral care is achieved, but noise increases

Engineering Contradiction:

Improvemultiple motion oral careVSAvoidnoise

Core Design Contradiction:

Adaptability or versatilityVSObject-generated harmful factors

Solution Approach 1:

The patent combines the drive mechanisms for primary and secondary motions into a single integrated drive assembly. The drive assembly includes an eccentric mechanism that generates both the oscillating primary motion of the brush member and the spinning secondary motion of the secondary bristle field, eliminating the need for separate mechanical linkages and reducing brushhead size.

Inventive Principle:

Principle #5Merging (Combining)

3Adaptability or versatility

If additional mechanical linkages are used to create secondary motion, then multiple motion oral care is achieved, but wear increases

Engineering Contradiction:

Improvemultiple motion oral careVSAvoidcomponent wear

Core Design Contradiction:

Adaptability or versatilityVSReliability

Solution Approach 1:

The patent combines the drive mechanisms for primary and secondary motions into a single integrated drive assembly. The drive assembly includes an eccentric mechanism that generates both the oscillating primary motion of the brush member and the spinning secondary motion of the secondary bristle field, eliminating the need for separate mechanical linkages and reducing brushhead size.

Inventive Principle:

Principle #5Merging (Combining)

4Adaptability or versatility

If additional mechanical linkages are used to create secondary motion, then multiple motion oral care is achieved, but device complexity increases

Engineering Contradiction:

Improvemultiple motion oral careVSAvoidassembly complexity

Core Design Contradiction:

Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent combines the drive mechanisms for primary and secondary motions into a single integrated drive assembly. The drive assembly includes an eccentric mechanism that generates both the oscillating primary motion of the brush member and the spinning secondary motion of the secondary bristle field, eliminating the need for separate mechanical linkages and reducing brushhead size.

Inventive Principle:

Principle #5Merging (Combining)

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 solution allows for effective multi-motion oral care without the drawbacks of additional mechanical linkages, reducing size, noise, and assembly complexity while maintaining the advantages of multiple motions in cleaning.

Implementation Method 1

the drive assembly moves the brush member and the first bristle field in a selected oscillating or other oral care motion

Methodology Applied

Scientific EffectOscillating motion: Vibration

Implementation Method 2

an eccentric, mounted for rotation on the bristle base plate, wherein the motion of the brush member imparts a spinning motion to the eccentric and an eccentric bristle field mounted thereon

Methodology Applied

Scientific EffectEccentric mechanism: Eccentric

Data Source

PatentEP2654614B1A power toothbrush and brushhead therefor, with multiple motion brush member

Publication Date: 2021.09.22 KONINKLIJKE PHILIPS NV

Figure 1~3
Figure 4A~4E

AI summary

The brushhead (14) includes a neck portion (15) which connects at a proximal end thereof to a handle portion (12) of a power toothbrush (10). At the distal end of the neck portion is a brush member (16, 28) which includes a bristle base plate (18, 34) and a bristle field (20, 36) mounted thereon. An eccentric (30) is mounted for spinning action on the bristle base plate, positioned in the midst of the bristle field. An eccentric bristle field (38) is mounted on the eccentric. The motion of the brush member produced by a toothbrush drive assembly creates a spinning motion of the eccentric and the eccentric bristle field mounted thereon, resulting in additional oral cleaning action.