Abstract: A cutter assembly for a dry shaver, comprising an elongate carrier member (221); and a cutter element (1210) having a plurality of turns forming a helix, each having an arcuate cutting portion (1211) and an arcuate mounting portion following sequentially along the helix; said carrier member being disposed substantially parallel to the axis (D-D) of said cutter element; and said carrier member contacting and supporting the mounting portions of the turns and leaving the cutting portions as free-span arches.

Abstract: A cutter assembly for a dry shaver, comprising an elongate carrier member (221); and a cutter element (1210) having a plurality of turns forming a helix, each having an arcuate cutting portion (1211) and an arcuate mounting portion following sequentially along the helix; said carrier member being disposed substantially parallel to the axis (D-D) of said cutter element; and said carrier member contacting and supporting the mounting portions of the turns and leaving the cutting portions as free-span arches.

Abstract: This invention employs a serrated or scalloped edge (7) on the undercutter of an electric razor to enhance the shaving performance. This improvement is achieved by promoting hair capture and retention and reducing the cutting forces required to sever the hair. The serrations and/or scallops (9) help retain the captured hair, thereby increasing hair cutting efficiency. They also reduce the tendency for the hair to “roll” along the edge of the foil aperture until it is trapped in the aperture angle; this promotes a closer shave. A serrated edge can be generated by various methods. In this disclosure, several possible methods are described. The preferred method of fabrication is to generate a weld bead on the outer surface of an undercutter blade and grind back the bead to generate sharp edges along the weld bead. In doing so, the weld bead produces a serrated pattern. The geometry of the serration is determined by the geometry of the weld bead.

Abstract: A shaving cutter (111) comprises a skin-engaging surface (116) having both a convex elliptic region (116a) and a hyperbolic region (116b). The elliptic region merges with the hyperbolic region along a parabolic transition region (117). Preferably, at least one of the surface regions is perforate. In addition, a concave parabolic skirt region (114) may depend from the hyperbolic region, while a convex parabolic skirt region (115) depends from the elliptic region. Methods of manufacturing the shaving cutter are also described.

Abstract: Foils are manufactured by creating a pattern on a substrate and then thickening the patterned film. The foil may then be peeled away from the substrate and/or pattern. The patterning step may include use of a laser or use of a photoresist, and may include deposition of a further layer. The thickening step may be performed by electrodeposition or electroless methods. The foils produced may be employed for dry shavers, sieves or filters.