Shear head of a dry-shaver comprising a shear foil which is clamped so as to be curved
US4621423A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 11, 1984 |
| Grant date | Nov 11, 1986 |
| Priority date | — |
| Expiry date | Oct 11, 2004 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB26B19/04
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A vibratory dry-shaver comprises a shear foil having two longitudinal edges, and respective means to clamp the two longitudinal edges in place to cause the shear foil to assume a natural curvature, the tangents to such curvature at the two clamping means forming an acute angle with each other. A cutter is reciprocatingly movable along and adjacent to the shear foil, the cutting edge of the cutter having a curvature corresponding to that of the clamped, curved shear foil. The curved shear foil and the cutting edge of the cutter each have a hyperbolic cosine curvature according to the formula: EQU y=c.multidot.cosh x/c where y indicates the distances of the individual cutting edge points from the x-axis, x is the coordinate in the direction of the width of the cutter, and c is a constant derived from the width 2b of the clamped shear foil and the height of the curvature h of the clamped shear foil.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.