Shaving Foil With Local Thickness Variation for Dry Shaver
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing shaving foils for dry shavers cause skin irritation due to their thin thickness, which is necessary for close shaving but leads to excessive skin contact and irritation, and they are not effective in guiding hairs smoothly.
Innovation Solution
A shaving foil with alternating thin and thick sections on its surface, where the thin sections cut hairs and raise flattened hairs, while the thick sections provide a smooth skin contact and mechanical strength, allowing for close shaving without irritation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If the shaving foil is made thin for close shaving, then the shaving closeness is improved, but the skin irritation increases
Solution Approach 1:
The shaving foil incorporates both thin sections and thick sections in specific locations. The thin sections (0.03-0.08mm) are positioned at cutting edges to achieve close shaving, while thick sections (0.08-0.15mm) are positioned at skin contact areas to prevent irritation. This spatial variation in thickness allows each region to perform its specific function optimally without compromising the other.
2Manufacturing precision
If the shaving foil is made thin to raise flattened hairs, then the effectiveness of cutting flattened hairs is improved, but the skin contact becomes too aggressive
Solution Approach 1:
The foil uses thin sections strategically positioned to interact with hairs while thick sections contact the skin. The thin sections effectively raise and cut flattened hairs, while the thick sections provide a cushioned skin interface that prevents excessive penetration and irritation.
3Manufacturing precision
If discrete protuberances are used to raise hairs, then the hair raising function is improved, but the skin guiding capability deteriorates
Solution Approach 1:
Instead of discrete protuberances, the invention uses continuous thin sections that extend between perforations. These thin sections provide a smooth surface for guiding skin and hairs, while still maintaining the ability to raise flattened hairs through their reduced thickness and flexibility.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A shaving foil (31) for a dry shaver has a plurality of perforations (32) arranged in an array. The shaving foil is formed in its skin contact surface with a plurality of recesses (130) which define a thin section of reduced thickness at the recesses, while leaving thick sections (132) at the remainder of the foil. Each perforation is configured to have its circumference defined partly by the thin section and partly by the thick section. Both of the thin and thick sections can come into contact with a user's skin for smoothly guiding hairs into the perforations to make close shaving without irritating the skin, while the shaving foil is moved across the skin. Especially, the thin sections act to cut the hairs shorter than the thick section, as well as to raise flattened hairs into the perforations for successfully cutting the flattened hairs.