1. Field of the Invention
The present invention is directed to a cutting head for reciprocatory-type shavers, and more particular to the mounting structure of a convexly curved shearing foil on the cutting head.
2. Description of the prior art
Reciprocatory-type shavers include a cutting head in which an outer shearing foil is convexly curved along an arcuate edge of a cooperative inner cutter and is secured at its opposite lower ends to a head frame. Generally, the head frame comprises a pair of opposed side bars between which the inner cutter extends. In the prior cutting heads, the shearing foil is held on the frame in such a manner that the opposite lower end portions of the shearing foil are secured to the inside of the respective side bars, as typically shown in U.S. Pat. No. 4,660,283. Such supporting structure of the shearing foil is found to pose the following problem while the cutting head is manipulated to move across the skin of the user as being pressed against the skin. During this manipulation a deformative force is very likely to act on one side of the shearing foil in the direction perpendicular to the length of the shearing foil. With this consequence, the inner cutter is correspondingly shifted to urge upon the other side of the shearing foil, whereby damaging or at least greatly wearing the portion of the shearing foil.
Further, with the prior structure of securing the lower end portions of the shearing foil to the inside of the frame, the side bars eventually add extra thickness to the lateral dimension of the curved shearing foil, thus leaving the cutting head rather bulky while the shearing foil may be curved into a sharp configuration. Such a bulky cutting head makes it to be difficult to follow a narrow complicated portion of the skin, such as under the chin or around the throat of the user, leaving uncut hairs at that portion.
USPTO Backgrounds
USPTO Backgrounds