Numbered Polygonal Razor Blades
Patent US1872721
Invention Safety Razor Blade and Razor
Filed Wednesday, 8th July 1931
Published Tuesday, 23rd August 1932
Inventor Albert Frank Ford
Language English
CPC Classification:B26B21/20
- B26B21/20
Safety razors with one or more blades arranged transversely to the handle involving blades with more than two cutting edges; involving disc blades - B
Performing Operations; Transporting - B26
Hand Cutting Tools; Cutting; Severing - B26B
Hand-Held Cutting Tools Not Otherwise Provided For - B26B21/00
Razors of the open or knife type; Safety razors or other shaving implements of the planing type; Hair-trimming devices involving a razor-blade; Equipment therefor - B26B21/08
Razors of the open or knife type; Safety razors or other shaving implements of the planing type; Hair-trimming devices involving a razor-blade; Equipment therefor involving changeable blades - B26B21/14
Safety razors with one or more blades arranged transversely to the handle - B
Performing Operations; Transporting - B26
Hand Cutting Tools; Cutting; Severing - B26B
Hand-Held Cutting Tools Not Otherwise Provided For - B26B21/00
Razors of the open or knife type; Safety razors or other shaving implements of the planing type; Hair-trimming devices involving a razor-blade; Equipment therefor - B26B21/54
Razor-blades - B26B21/56
Razor-blades characterised by the shape
For a full resolution version of the images click here
A PDF version of the original patent can be found here.
Parts not referenced in the text: None
Parts not referenced in the images: None
It is well known that razors give better service if the blade after being used is given a rest. Such a rest should exceed one day in length, and better service is forth-coming if the edge has three, four or more days rest between each use.
It is known that safety razor blades with more than
Besides, the various kinds of polygonal blades heretofore proposed for this purpose do not have a sufficient number of alternately usable edges to provide for a sufficient rest period for each edge to recover before it is to be used again.
The main object of this invention is to provide a polygonal razor blade of the wafer type which carries indicia designating the successive days of the month so that the user, in order to determine which edge to use on any particular date, may only have to know wheat particular day of the month it is and not need to remember otherwise which of the edges of the blade has previously been used.
Another object of this invention is to provide such a blade with a sufficient number of edges and with such a method of placing with indicia thereon that there will be provided sufficient length of rest period between successive uses of the same edge.
A still further object of the invention is to provide suitable means in such blades, in conjunction with suitably constructed holders, to properly distribute the stresses arising in the blade from the necessary clamping action, so as to stiffen the working edge in a satisfactory manner.
An object of this invention is also to provide a holder for such blades as above described in which ordinary
With these and other objects in view which will hereinafter appear, the invention consists in a razor blade with multiple cutting edges provided with indicia designating the successive days of the month and a suitable holder for the same.
In carrying out this invention, a razor blade of the wafer type with at least 3, but preferably more, cutting edges is provided, having numbers applied to these cutting edges in various sequences, such numbers being identical with the number of days in a month, preferably from 1 to 31, but it is understood that they may run from say 1 to 15, 16 to 31 or any other sub-division of a month, as will hereinafter be further described.
With the ordinary wafer blade the surface of the holder to which the blade is clamped is cambered so that when clamped in position the blade is flexed. This flexing gives the blade as a whole an arched form, and such form no doubt stiffens up to
According to the present invention the flexture
The holder which I provide for these blades, preferably has a convex or dome-like surface to which the blade is clamped by the guard or cover part and in which apertures or notches are provided through which the date numbers may be seen.
The razor blades according to this invention preferably have the corners between their contiguous sides removed and notches formed in these corners in order to give the cutting edges greater flexibility when bent while being clamped in the holder.
When the said razor blade is triangular in shape the date numbers
In this case in order to avoid a multiplicity of numbers on each edge the numbers may be divided and part placed on one side of the blade and the rest on the other side. For example a triangular blade may have the dates
Where the blade is one having four sharpened edges the dates
In this case again alternate date numbers on each edge may be divided, half being on one side of the blade and the other half on the other side of the blade.
Where the razor blade has six cutting edges the dates
Where the razor blade has eight cutting edges it may have the dates
If preferred the alternate dates on any particular edge may be divided, one half being on one side of the blade along said edge, the other half being on the other side of the blade.
Where the number dates marked on a razor blade edge are divided, some of the dates being on one side of the blade and others on the other side, the dates on the one side may be arranged to read as a series in a clockwise manner, and those on the other side, the alternate dates thereto, as a series in the anti-clockwise manner.
The razor blades according to this invention have a number of positioning holes provided therein, corresponding to the number of their cutting edges, and a center hole for the passage therethrough of the stem of the holder. The holder is provided with a corresponding number of studs for engaging the positioning holes. The notches in the corners of the blades may be cut through to the positioning holes and continued at the diametrically opposite side of the holes to near the center of the blade for the purpose of greater flexibility of the blade and its adaptability to the shape to which it is deformed when clamped in the holder.
In the modification wherein the blade has four cutting edges the invention includes the combination of a holder with a blade with four positioning holes punched through the blade, the size of the holder and of its normal blade and the position of said positioning holes in the blade and of the positioning studs on the holder being such that ordinary two-edged blades with the standard spacing of positioning apertures therein may, if desired, be clamped.in said holder and be used as a make-shift if the proper blades therefor are not available.
The invention will now be described with reference to the accompanying drawing, in which :—
In
To give flexibility the corners are removed and notched at
It will be noted the numerals on the edges of the blade indicate the dates on which the particular edge should be used. Considering edge
In
This has four nicks
A blade as shown in
In these various figures the date numbers on the blade are the numbers on the one side of the blade, whilst the date numbers outside the blade surface represent dates stamped on the other side of the blade.
The notching shown comprises the removal of the corners as shown at
Referring now to
In
In
It is important to be able to see the date numbers on the blade when clamped in the holder.
The holder therefore may be notched or apertured in any convenient manner to expose the date figures.
In
This shows a square blade such as that shown in
This
The blade
The central portion of the bent surface of diameter
In
It will be understood that by varying the distance to which the slots
It should be noted that where in this specification reference is made to dome-like stresses it does not necessarily mean stresses such as are developed in a masonry dome but to stresses which are developed in a thin metal sheet or plate when it is buckled or is forced to assume a saucer-like form from its original state in which it was flat. These stresses are very different from those developed in the standard type of razor blade which is bent in a direction perpendicular to its cutting edges into what has been referred to herein as the arch form in which the convex side of the blade is in pure tension and the concave side in pure compression and the edges are stiffened up by the deformation.
Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is :—
1. A safety razor comprising a holder, a blade having a plurality of cutting edges, identifying numbers corresponding to certain days of the month on said blade adjacent each edge thereof, a guard plate having a plurality of teeth along its edges, the spaces between certain adjacent teeth along the edges of said guard plate terminating in circular apertures to expose said identifying numbers on the blade.
2. A safety razor comprising a holder, a multisided blade having indicia numbers from 1 to 31 corresponding to the days of the month adjacent the edges of said blade, a toothed guard having the spaces between adjacent teeth further indented at spaced intervals to reveal said indicia numbers thereby to facilitate the successive use of the edges of the blade upon successive days of the month.
In testimony whereof I hereto affix my signature this 4th day of June, 1931.
Albert Frank Ford.