US2422048A

US2422048A - Safety-razor blade sharpener

Info

Publication number: US2422048A
Application number: US595137A
Authority: US
Inventors: John W Sharp
Original assignee: Individual
Current assignee: Individual
Priority date: 1945-05-22
Filing date: 1945-05-22
Publication date: 1947-06-10
Anticipated expiration: 1964-06-10

Description

J.W. SHARP SAFETY RAZOR BLADE SHARPENER June 1o, 1947.

Filed.- May 22, 1945 Flq 1 .AT TORNE Y Patented June 10, 1947 UNITED `STATES PATENT OFFICE Y 2,422,048` l. l

SAFETY-Razon BLADE snAnPENEn `John W. sharp, Muncie, Ina.

` Application May 22, 1945, Serial No. 595,137

2 Claims. 1 This invention relates to improvements in implements for facilitating the sharpening of safety razor blades.

By reason of Vthe fact that a blade of the above description is an entity rectangular inplan forz mation and without a handle, and that the longitudinal parallel margins thereof are very thin and extremely flexible, the blade does not lend itself to conventional procedures; experience has taught that the moving of the blade over a Whetstone or hone having a flat or extended surface, even when such a blade may be held by means designed to maintain the margins of the blade against flexing, has been unsatisfactory. Attrition at the edge ofthe margin of the blade is not only too severe, but also, it s notuniform throughout the extent of said margin.

In developing my invention I have kept in mind that the margin of the safety razor blade, as distinguished from the margin of a blade of most every other kind, is extremely thin and unusually flexible; and that it is possessed of a microscopically toothed and keen shaving edge such as may only be afforded by the specialprocedures which are incident to the manufacture of said blade. Also I have considered that whereas after repeated use of such a blade its eiciency as a razor may have become reduced;` it should not be assumed, as so often hasbeen done, in the prior art;` that te recondition the blade, a conventional whetting or honing operation is, necessary or desirable. To the contrary, my experiments have proven that an extremely light and delicate degree of pressure interacting between the abradant element of whatever character, and the edge of thel margin of the blade is essential, if an edge which is uniformly keen and sharp from end to end of the margin of the blade is to be obtained.

-To provide means whereby Vin subjecting the bladefto a sharpening procedure, the attrition imposed on the blade may be of the nature of rubbing or smoothing, rather than of grinding or abrading such asby the use of a conventional whetstone, strop or hone; and that the contacting of the margins of the blade with the abradant element, while being steady and constant, shall at the same time befuniform from end to end of the margins of the blade, is the object, broadly stated, of my invention. l

An abradant body which lends itself especially to the aims of my invention consistsof a slab having a whetting face convex in cross section and of concaveflcurvature longitudinally; it thus being'adapted to engage only the outboard edges of the margins ofthe blade.` My invention consists of a device adapted to be held by one hand of the user to support a slab of the above description in such manner that while holding the blade at its ends by the fingers of the other hand, the slab and the blade may be so manipulated with relation to each other that the contact between the slab and blade is cushioned, and during which said transaction the-yield or flexing of the edge portion `of the margin of the blade immediately at the whetting face of the said slab is uniformly affected.

The said generalobject, as Well as other and more specific aims as will presently appear, are accomplished by and my invention is embodied in the new construction, combination and arrangement of parts described in the following specification and illustrated in the accompanying drawings, in whichi Figure 1 is a side view of the abradant slab.

Figure 2 is a vertical central cross sectionvew, taken on the broken line 2--2 in Figure 1.

Figure 3 is a. fragmentary enlarged view illustrative of a typical curvature of the Whetting face of said abradant slab, and of the position of a conventional safety razor blade, with relation thereto.

Figure 4 is a perspective view indicative of the positions in Vwhich the said abradant slab and the safety razor blade are held by the user preliminary to their being disposed in contacting relation;

' Figure 5 is a perspective view illustrating the flexing of the edge of the margin of the blade as it is passed across the whetting face yof the slab.

Figure 6 is a side view showing the appearance of the abradant body or slab when supported by a mechanical cushioning device, said device being shown mainly in vertical central cross section.

Figure 7 is a view of Figure 6 in the direction of arrow 1.

`Figure 8 is a view of Figure 6 in the direction of arrow 8.

Figure 9 illustrates a slab of modified form.

The slab consists of a slablike structure of hard, ne grained dense material such as whet slate I2 which is of thickness equivalent to not less than twice the distance between the plane of one end of the 'body portion of the blade and the plane of the adjacent ends of the marginal portions of said blade to provide a Whettingface I4. `This Whetting face isconcave from end to end and is transversely convex, as indicated in Figure 1 and in Figure 2. Its degree of curvature, from end to end, for accommodating a blade f the typical example shown is that of an arc struck from a radius of about four inches, and its surface is dressed to a polished finish. The enlarged detail View Figure 3 is illustrative of the border portion of the slab embodying said Wheting face, and it indicates the position of the blade when same will have been disposed in position with the extreme edge ,portionsfof the lmargins of the blade in rubbing engagement with said whetting face.

For supporting the slab I have provided a holder device of construction indicated in yFigures 6, 7, and 8. l

I3 designates a tubular body of the suitable proportions shown and which I designate as a handle. A tonguelike portion sliced longitudinally from, and which is bent inwardly of the upper portion of said handle constitutes a lug I9; and the opening which is incidentfto said slicing constitutes a gap 20.

A tubular sleeve 2i which I designate as a holder is of diameter to be slidingly received and retained within the said handle, and it is provided at its upper portion vwith a central longitudinal bifurcation 22. -The

opposed sides

26 and 28 of said holder are strained slightly toward each other and theyconstitute fork arms, the inner face of each arm being provided with a shallow offset 29. Near the lower end of said holder is an inwardly directed lug 30. A retractile helical spring 32 has its lower end secured to said lug 3B.

To assemble the parts just described, the holder 2| is inserted inthe lower end of the handle I8 and is moved vupwardly to projected position, the bifurcation 22 clearing the lug I9 of the handle. By means of a suitable implement (such as a bent wire hook not shown) inserted either through the upper portion of the holder or through bifurcation 22and gap 2l] the eye of said spring is disposed in connected engagement with the lug I9 of the said handle. The holder now, by the tension 0f the spring 32 is urged upwardly, and by reason of the bottom 23 of bifurcation 22 meeting the lug I9, is retained in thenormal upward status shown. Between the offsets 29and 29 of the fork arms of said holder, is inserted the slab I2 its lower portion being securely gripped by the fork 4rarms of said holder. The bottom of the handle lI8 is suitably finished as by a cap 34.

The retractile spring 32 interacting, as it does', between the lug I9 of the handle I8; and the lug 300i the holder 2|, sustains the holder, as before stated, yieldingly in the raised position. At the same time, it functions as a means to connect the vholder to said handle. Thus, the above construction affords a cushioning and which is a preventive against a too severe contacted c0- engagement of the whetting face I4 of the slab and the blade margins.

To provide for sharpening of a single-edged blade, or of a blade of lesser width than that of the standard conventional blade shown herein, I provide a slab of formation embodying a plurality of Whetting faces vwhich are differentiated in end-to-end contour, as typically illustrated in the modification at Figure 9, each of said faces being identified by a reference character. For example, the curvature dictated by an arc struck from a radius of three and three quarters inches being marked B; and curvatures derived from shorter radii being marked C, D, and E. "Whet slatebeing a stone of fine grained, hard and dense-structure, and lending itself vespecially tothe procedure with which my invention is concerned, it is recommended asy being the material preferred for the abradant body, although other material having the above characteristics may be found practicable.

It will be understood that my invention is capable of minor modifications within the scope of same as it is defined in the claims, without departing from the principle or spirit of the invention or sacrificing any of its advantages.

Procedure in using the invention is as follows llhe slab having been placed between the fork arms of the sleeve 2| the user now, with the handle I8 grasped, say, by his left hand, and while holding the blade at its ends by the thumb and forenger of his other hand, brings the blade and slab into contacted relation, the edge portions I6 of the margins of the blade being intimately coengaged with the Whetting face I4 of the slab, as indicated in Figure 3. The yield of spring 32 .while serving to support the slab prevents a too severe urge toward each other, of the slab and the blade, so that in the transaction of shifting the blade reciprocatively across the Whetting face I4 of the slab, there is obtained a delicate rubbing irictional contactual traversing of the edge portions I6 of the rmargins of said blade, from one end to the other of said margins. The thumb and forenger at the opposite ends of said blade meeting, as they do, the opposite side faces of said slab, the length 0f the stroke of the blade while thus having been limited, will have been suicient for the blade margins to have traversed the whetting face I4 their entire length.

The said whetting face being convex in cross section contour, and the curvature longitudinally of said face being such that the edges only of said blade meet said face, it is obvious that in the transaction of moving the blade, the edge portions IB of the margins, flexible as they are, and yielding as they do, are enabled to be in such frictional engagement with the said whetting face that every particle of said edge portion of the margin is affected. By the above described procedure, the edge portion of said blade margin is worn with such uniformity and nicety that whereas there is accomplished the effective sharpening attrition of the metal, there is no breaking down or impairment of the microscopic teeth thereof. The opposite side surfaces of the slab constitute stops for the thumb at one end of the blade, and for the foreiinger at the other end of the blade, whereby as said thumb and linger meet alternately with the said side surfaces of the slab, the range of each stroke of the blade is limited to the distance necessary for the end of the blade margin to have passed the crest of the whetting face I4 of the slab.

What I claim as my invention, is:

1. In combination with a slab shaped abradant body having a polished whetting face relatively narrow in width, concave from end to end and transversely convex and adapted to be traversed by the opposed longitudinal edge portions of the margins of a safety razor blade, a handle, a holder device consisting of a tubular sleeve provided at its upper portion with a central longitudinal bifurcation in the outboard area of which the said abradant body is made fast, there being provided at the lower end of said sleeve an inturned lug, a

tubular handle within which the said sleeve is slidingly receivedsaid handle having an inturned lug which is received in ythe bifurcation of said sleeve, and a retractile spring having the ends thereof connected with said lugs whereby the sleeve is supported yieldingly in said handle.

2. In combination with an abradant slab having a whetting face convex in cross section and concave from end to end, a holder device therefor consisting of a tubular sleeve provided at its upper portion with a central longitudinal bifurcation the opposed sides thereof being strained toward each other and each having an offset to engage a side of said slab, there being provided at the lower portion of said sleeve an inturned lug, and a tubular handle within which the said sleeve is received, said handle having an inturned lug at its upper portion and which is received in the bifurcation of said sleeve, andra, retractile tension member interconnecting the said lugs.

JOHN W. SHARP.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS