US 3654701 A
An improved safety razor blade having a cutting edge in the form of a continuous series of substantially sinusoidal micro-waves which provide more cutting surface per unit of length than a smooth- or straight-edged blade and which achieve maximum closeness and comfort of shaving action without angling the blade to the direction of the shaving stroke. The improved blade is adaptable to most of the standard safety razors utilizing either single- or double-edge blades, as well as those of the narrow band or reel type flexible blades. For optimum results, the micro-waves of the cutting edges of the blades are very minute and preferably range in wave depth from crest to trough on the order of between 0.0005 inch minimum depth to about 0.0050 inch maximum depth, and the waves numbering on the order from between about 100 or 200 per inch to about 20 per inch of blade length.
Claims available in
Description (OCR text may contain errors)
United States Patent Hastings, Sr. Apr. 11, 19 72 54] SAFETY RAZOR BLADE Primary Examiner-Andrew R. .luhasz 72 Inventor: Donald M. Hastings, Sr., PO. Box 4088,
Atlanta, Ga. 30302 Attorney-Robb & Robb  ABSTRACT An improved safety razor blade having a cutting edge in the form of a continuous series of substantially sinusoidal microof the narrow band or reel type flexible blades. For optimum results, the micro-waves of the cutting edges of the blades are very minute and preferably range in wave depth from crest to trough on the order of between 0.0005 inch minimum depth to about 00050 inch maximum depth, and the waves numbering on the order from between about 100 or 200 per inch to about 20 per inch of blade length.
1 Claims, Drawing Figures PATENTEBAPR 1 1 I972 INVENTOR D. M. HASTINGS,Sr.
ATTORNEY) SAFETY RAZOR BLADE The present invention relates to improved safety razor blades, and more particularly, to more effective and efficient cutting edges for such blades.
The primary object of the invention is to provide an improved razor blade having a cutting edge which presents a greater effective cutting edge per unit of length than conventional smooth-edged or straight-edged blades and which achieves an optimum closeness and comfort of its shaving action without the necessity of slanting or angling the blade to the direction of the shaving strokes.
In its preferred embodiment, the cutting edge of my improved razor blade has the form of a continuous series of substantially sinusoidal micro-waves consisting of extremely minute scallops. While serrated or scalloped cutting edges have heretofore been utilized in some tonsorial and other cutting implements, the serrations or scallops thereof have usually been relatively coarse and/or otherwise improperly shaped and have therefore been unsatisfactory for razor blades as used in shaving the face. I have found that a commercially feasible and highly satisfactory shaving action can be achieved by forming the cutting edge of the razor blade with a continuous series of micro-waves in a critical range of between about 100 and 200 per inch but no fewer than about 20 per inch of blade length, with the depth of each wave from crest to trough being selected within the critical range of from about 0.0005 inch and 0.0050 inch.
A further object of my invention is to provide a safety razor blade having an improved cutting edge of the aforementioned type and which can be utilized for most standard type razors, including those designed for the newer type narrow blades of the flexible band or reel types.
Other and further objects of my invention will be hereinafter described or will be apparent from the following description and the accompanying drawing and the novel features defined in the appended claims.
In the drawing:
FIG. 1 is a top plan view of a conventional safety razor as equipped with my improved type of blade;
FIG. 2 is a fragmentary view of the razor of FIG. 1 as primarily depicted in transverse cross-section and with portions shown in elevation;
FIG. 3 is a plan view of one illustrative double-edged razor blade embodying my invention.
FIG. 4 is an enlarged fragmentary plan view of the encircled portion of the blade of FIG. 3 to better show the micro-waved form of one cutting edge of the blade;
FIG. 5 is a fragmentary plan view similar to FIG. 4, showing the cutting edge of the blade on a different enlarged scale and having a cutting edge of slightly modified form;
FIG. 6 is a perspective view of a so-called flexible band type razor showing the blade in the form of a narrow band having its cutting edges conforming to my invention; and
FIG. 7 is a perspective detail view of the unmounted blade of FIG. 6.
Like reference characters designate corresponding parts in the several figures of the drawing, wherein I denotes the frame of a conventional safety razor having the usual handle 2 extended therefrom. The razor has the usual clamping guard 3 for clamping the razor blade 4 between the guard and the frame in the usual manner of such conventional safety razors.
In the illustrative embodiment, the blade 4 is shown as being a double-edged type of blade, but it is to be understood that my invention is not confined thereto, but is applicable to single-edged blades as well. My invention is more particularly concerned with the improved form of the cutting edges of the blades, as best seen in FIGS. 3 and 4. As shown, each cutting edge is generally designated 5 and has the form of a continuous series of minute scallops 6 as illustrated on an enlarged scale in FIG. 4, said scallops corresponding to microwaves of substantially sinusoidal shape. The cutting edges of the blade are bevelled as customary to give the same the sharpness of cutting actionas required for shaving, and because of the micro-waved 'form of the cutting edges, a greater effective cutting length per unit of blade length than a smooth or straight edge is provided.
I have found that to achieve optimum closeness and comfort of shaving action, the critical range lies from between and 200 scallops 0r micro-waves per inch of blade length, to no fewer than 20 per inch, while the critical wave depth from crest to trough, designated as D in the drawing, ranges between 0.0005 inch and 0.0050 inch. Various combinations of these factors can be selected according to the sensitiveness of the facial skin to be shaved, as by classifying the blades in several major classes such as fine, extra fine and super fine", or other appropriate denominations.
Referring to FIGS. 6 and 7, another type of razor blade is illustrated as a flexible narrow band or reel type blade and embodying my improved scalloped or micro-wave cutting edges, said blade being generally designated 4', with the cutting edges being designated 5' and the scallops 6, and conforming to the respective cutting edge features of FIGS. 1-4 as described above.
While the specific details of my invention have been herein shown and described, the invention is not confined thereto as changes and alterations may be made without departing from the spirit thereof as defined in the appended claims.
l. A safety razor blade having a cutting edge of minutely scalloped form and conforming to a continuous and uniform series of sinusoidal micro-waves all lying wholly in the plane of the flat blade body, with the troughs between each adjacent pairs of wave crests being of a size approximating the size of an individual human facial hair, said waves ranging in number on the order of between about 100 and 200 per inch of blade length, and the depth from crest to trough ranging on the order of between 0.0005 inch and 0.0050 inch.