Masking Foil Securing Elements for Blade Exposure

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing safety razors with masking foils face challenges in maintaining efficient shaving performance due to the assembly of masking foils affecting blade edge exposure and spring stress, and non-conductive masking foils can lose cathodic protection, impacting shaving efficiency and safety.

Innovation Solution

A masking foil design with a securing portion comprising a cross-member and laterally extending securing elements, which provides rigidity and secure assembly without affecting blade edge exposure or spring stress, and can be made of conductive or non-conductive materials, including a lubricating coating for improved skin interaction.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the masking foil is assembled after production with flat and wide securing portions between the blade edges and the retainer, then the masking foil provides skin protection and hair alignment, but the blade edges become less exposed reducing shaving efficiency

Engineering Contradiction:
Improveskin protectionVSAvoidshaving efficiency
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The masking foil is divided into functional zones: a securing portion with cross-members and securing elements for attachment, and a blade coverage portion with ribbons for protection and alignment. This segmentation allows the securing portion to be positioned away from the blade edges, maintaining blade exposure while providing secure attachment.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The securing elements extend laterally outwardly from the cross-member in a direction perpendicular to the blade edges, positioning the securing mechanism in a different spatial dimension that does not interfere with blade edge exposure to the shaving plane.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Reliability

If the masking foil is assembled after production with securing portions between the blade edges and the retainer, then the masking foil can be securely attached, but the spring fingers are more intensely stressed reducing sensitivity to skin shape

Engineering Contradiction:
Improveattachment securityVSAvoidspring sensitivity
Core Design Contradiction:
ReliabilityVSAdaptability or versatility

Solution Approach 1:

The securing function is extracted from the blade-spring interaction zone and placed in a separate location using cross-members and securing elements. This removes the additional stress from the spring fingers while maintaining secure attachment of the masking foil.

Inventive Principle:
Principle #2Taking out (Extraction)

3Object-affected harmful factors

If the masking foil is made of non-conductive material for skin safety, then the masking foil provides electrical insulation, but the cathodic protection offered by the retainer to the blades is lost

Engineering Contradiction:
Improveelectrical safetyVSAvoidcathodic protection
Core Design Contradiction:
Object-affected harmful factorsVSReliability

Solution Approach 1:

The masking foil acts as an intermediary element that can be made of non-conductive material for electrical safety, while the retainer maintains its cathodic protection function for the blades. The securing portion design allows the non-conductive material to be positioned such that it does not interfere with the electrochemical protection mechanism between the retainer and blades.

Inventive Principle:
Principle #24Intermediary (Mediator)

4Reliability

If the masking foil has flat and wide securing portions for secure assembly, then the masking foil is firmly retained, but the device complexity increases

Engineering Contradiction:
Improveretention securityVSAvoidstructure complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The masking foil utilizes a thin film structure with integrated cross-members and securing elements, maintaining firm retention through the geometric configuration of the securing elements rather than increasing overall thickness or complexity of the foil structure.

Inventive Principle:
Principle #30Flexible shells and thin films

Data Source

PatentEP4098414B1Blade masking foil with inter-blade securing elements
Publication Date: 2024.03.06 BIC VIOLEX SINGLE MEMBER SA
  • EP4098414B1 patent drawingFigure 1
  • EP4098414B1 patent drawingFigure 2~3
  • EP4098414B1 patent drawingFigure 4

AI summary

A masking foil (26) for a shaving cartridge comprising a front side (28), a back side (30), a pair of lateral sides (9), at least one ribbon (32) extending along a top side (8) of the masking foil (26) between the front side (28) and the back side (30), and a first securing portion (34) located at one of the pair of lateral sides (9). The first securing portion (34) comprises a cross-member (341) extending along the top side (8) of the masking foil (26) between the front side (28) and the back side (30), and at least two securing elements (342) extending laterally outwardly from the cross-member (341).