US1798448A - Safety razor - Google Patents

Description

Mimh 31,1931. BE RM 1,798,448

SAFETY RAZOR Filed Dec. 23, 1927 IN V EN TOR 17! cwliBe BY M ATTORNEY Patented Mar. 31, 1931 UNITED STATES PATENT OFFICE BIARCUS B. BEHRMAN, OF BROOKLYN, NEW YORK, ASSIGNOR- T0 AMERICAN SfiFETY RAZOR CORPORATION, OF BROOKLYN, NEW YORK, A CORPORATION OF VIRGINIA SAFETY RAZOR Application filed December 23, 1927. Serial No. 242,072.

My present invention relates generally to razors and to blades therefor, and is directed to an arrangement whereby the blade can be associated with the razor so as to have the shaving edge always in that predetermined positional relationship with reference to the guards at which the maximum efficient shaving action is obtainable, and more particularly to such an arrangement in connection with a double-edged blade of the wafer type.

It is a well-recognized fact that where a razor is constructed to have the cutting edge positioned along a certain line across the guard, that any deviation from this position will affect the shaving operation. For example, if the edge of the blade is too far forward the safety factor of the razor will be minimized, if not eliminated, and cutting and slashing of the face result, and, on the other hand, if the shaving edge is positioned to the rear of this line the shaving efficiency will be materially reduced and the shaving action not effective. In fact, I have found by actual experiment that a postional error which results in the cutting edge being as little as .002 inches to the rear of the line along which maximum efficiency is obtainable, will cause the blade to be defective in its operation, regardless of how perfect a cutting edge may have been given to that blade. Where complaints by users are made that one blade of a given manufacturer shaves well, whereas a second blade by the same manufacturer shaves poorly, it will be found that the inefliciency of certain blades is due not to character of the shaving edge but to the fact that this edge is not at the predetermined line intended for that particular razor.

In a razor of the type wherein a doubleedged wafer type blade is employed, and wherein the relation of the cutting edges with reference to the guards is predetermined by means of pins on the razor saddle, these pins engaging through holes in the blade inter mediatethe cutting edges, the following sources of error will necessarily arise: (1) The stamping operation may create an error in the dimension of the blade from edge to edge, or in the position of the holes which should be exactly equidistant between these two edges. (2) Even if the punching and stamping operations of the blanks are assumed to be entirely accurate, so as to provide absolutely uniform blanks provided with holes absolutely uniformly punched and positioned. it is a well-known fact that in the processing of the edges to convert them into cutting edges, errors will necessarily arise. That is, the amount of material taken off one edge in the processing may not be the same as the amount of material taken off the opposite edge; and the amount of material taken off an edge of one blank may not be the same as the amount of material taken off the edge of a different blank. Even assuming, therefore, that in the punching operation thelioles are accurately positioned, there is no assurance that the cutting edges of the completed blade will position themselves along the predetermined line of maximum efiicien In fact, actual tests of blades on the market show a variation between the position of edges of different blades with reference to this predetermined line of maximum efficiency as high as .011 inches; and it is'to be noted that a cutting edge which falls short of this line of maximum efficiency by a factor only as high as .008 inches will be found to be absolutely inefficient for shaving purposes.

In single-edged razors of the type illusrated by the Evercady and the Gem, these errors of manufacture are eliminated as factors in the proper location of the blade by providing blade stops in association with the guard edge which predetermine the proper positioning of the cutting edge along that line which results in maximum shaving efficiency. Patent No. 1,488,907 exemplifies this arrangement, wherein springs or similar elements engaging the unsharpened rear edge of the blade serve to hold the extreme outer portions of the cutting edge in contact with these blade stops.

While an arrangement of the foregoing character results in perfect location of the single-edged blade when the razor is first used, I have found that continual use frequently results in the tendency of the cutting edge, when forced against the blade stops, to out into these stops, and therefore to some extent permits the blade to advance slightly beyond the aforementioned line of maximum etficiency. Furthermore, the employment of what I might term the Eveready principle, i. e., the engagement of the cutting edge by front blade stops and the engagement of the unsharpened edge by blade-advancing members, presents new problems where it is desired to employ a double-edged blade, for the reason that the engagement by spring members or the like with a sharpened edge, as in Patent No. 1,488,907, will necessarily affect that cutting edge adversely.

Furthermore, in the employment of the socalled Eveready principle, there are other important factors which must be considered, among which are the following: T he effective length of the shaving edge must not be materially reduced. (2) The shaving edge when brought up against the front blade stops must be properly aligned so as to be parallel to and in fact coincident with the aforementioned theoretical line of maximum eiiiciency. The blade must be properly centered.

One of the features of my invention lies in providing locating means which on the one hand approximate the front stop principle and which on the other hand serve to center the blade. In the illustrated embodiment this takes the form of a wafer-type blade h aving beveled side edges, and a razor holder provided with blade stops adapted to cooperate with said beveled side edges for properly positioning the operative edge over the guard edge. More particularly, it is a feature of my invent-ion to provide beveled blade stops in preeetermined association with the guard edge for receiving the beveled side edges of the blade in wedged relationship therebe- .tween.

Another feature of my invention lies in providing a blade of the foregoing character which is symmetrical about an axis parallel to its front and rear edges, thereby rendering the blade reversible; and in providing a holder so designed as to receivea blade in proper predetermined relationship, resulting in maximum efiiciency, in either normal or reversed position.

More particularly, it is a feature of my invention to provide a razor holder for use with a double-edged wafer-type blade, symmetrical about an axis parallel to the cutting edges, wherein blade stops associated with the guard edge are designed to cooperate with the beveled side edges adjacent to the selected operative cutting edge, and wherein bla le-advancing members are designed to cooperate with the beveled side edges momentarily positioned toward the rear, i. e., adjacent to the momentarily inoperative cutting edge.

Among the objects of my invention, there fore, are the provision in a razor adapted to receive a double-edged blade of bladepositioning means which minimizes as factors any errors arising in the manufacture of the blade; the provision of blade-positioning means which eliminates as a factor any errors due to continued use of the blade or razor; the provision of means for positioning the blade by an approximation of front stops without materially reducing the effective length of the operative cutting edge; the provision of means, in a razor wherein the blade is automatically forced forward against stops, for properly positioning and centering the blade; the provision of an arrangement whereby the socalled Eveready principle may be efliciently employed with a double-edged blade; the provision of an arrangement, in a separable blade and razor holder, intended when associated, to operate with increased eiiiciency, for preventing the use with such razor holder of any blade other than that intended therefor; and the provision in general of a new and improved razor holder, and of a new and improved blade for employment therewith.

While the razor holder and the razor blade herein to be fully illustrated and described each presents certain inherent advantages of its own, yet the efliciency of the razor will be at its maximum when a blade is used therewith which is of a character intended to be associated therewith and herein disclosed. It is accordingly one of the objects of the present invention, in order that the razor may be used most effectively to construct the razor in such a manner that only that type of blade is usable therewith which is herein disclosed and which results in that efficiency.

For the attainment of the foregoing objects and such other objects as may hereinafter appear or be pointed out, I have constructed a device embodying the features of my invention and illustrated in the accompanying drawings, in which Fig. 1 is a plan view of aholder having a pivotal cover, the cover being shown open, and a blade of the present invention being shown in accommodation upon the blade seat;

Fig. 2 is an end view of the device with the cover closed and with a portion thereof broken away to disclose the blade thereunder;

Fig. 3 is a fragmentary cross-sectional view taken substantially along the line 33 of Figure 2;

Fig. 4 is a fragmentary perspective view of the side of the device with the cover closed;

Fig. 5 is a diagrammatic representation, in plan, of a modification; and

Fig. 6 is a view similar to Figure 5 showing a second modification.

The holder illustrated in the accompanying drawings comprises a blade seat or sadconverge towards each cutting edge.

dle 10 having a guard edge 11 and a pivotal cover 12. In the device illustrated, the cover is mounted upon pivot pins 13 arranged at opposite ends of the guard edge 11, the cover 12 being thereby thrown forwardly when it is opened and rearwardly over the blade seat 10 when it is closed. The pivoting of the cover is provided for by extending the sides 14 thereof into engagement with the pins 13; and the top or main portion of the cover terminates in a front edge 15 which is so positioned that it will cover the major portion of the blade when the cover is closed and still leave the forward cutting edge of the blade exposed.

The line of maximum shaving efficiency, i. e., the line along which the cutting edge must lie in order best to achieve both shaving and safety functions, depends of course upon the particular structure of the guard edge 11. In Figure 1, the edge 16 of the blade 17 is shown arranged along this line of maximum efiiciency. Inorder to assure such proper positioning in all cases, I construct the blade and the cooperating portions of the holder in the manner illustrated and now to be described.

The blade embodies not only the edge 18, but also an opposite cutting edge 18, and the blade is symmetrical around a medial axis parallel and between the edges 16 and 18. The sidesof the blade are beveled so asp 1to 1e blade illustrated is therefore octagonal, although it will be understood that a hexagonal construction would achieve substantially the same purpose. The beveled portions 19 arranged adjacent to the edge 16 converge toward that edge, and the portions 20, symmetrical with the portions 19 about said medial axis, converge toward the opposite edge 18. The blade is therefore reversible, and may be positioned in the same efiicient manner with the edge 18 substituted for the edge 16 in Figure 1.

Essentially, it will be noted that each of the converging portions 19 and 20 constitute a portion of the side of the blade which includes two points defining a line oblique to the cutting edge. Wherever the term beveled or converging is used in this specification or in the appended claims, it will be understood that these terms define a construction wherein at least two points define such an oblique line. On opposite sides of the guard edge 11, I provide the beveled blade stops 21, each of these stops presenting an oblique surface against which the two points referred to may abut. In other words, the blade is adapted to position itself in wedged relationship between the blade stops 21, and needless to say, these stops are so positioned with respect to the guard edge that when the proper blade is applied to the blade seat and against these stops, the front cutting edge of the blade will coincide with the line of maximum efficiency.

The momentarily inoperative converging side portions 20 are utilized, in accordance with my invention, for the purpose of advancing the blade along the seat. More par ticularly, angularly disposed spring members or blade-advancing members 22 are carried by the cover, preferably integral therewith, and are so positioned and arranged that when the cover is closed over the seated blade, the members 22 will bear directly against the momentarily rearward bevels 20 so as to wedge or force the blade forwardly.

Referring to Figures 2, 3, and 4:, it will be noted that the opposite rear corners 'of the blade seat 10 are bent downwardly as at 23 to permit the blade-advancing members 22 to pass downwardly when the cover is closed. It will also be noted that the members 22 may be advantageously provided as integral portions of the sides 14 of the cover by cutting a pair of parallel slits 24 in each side 14 and properly twisting and shaping the material thercbetween. The twisting is accomplished for the purpose of arranging these bladeengaging members obliquely as shown in Figure 1 so as to be directly operable against the obliquely arranged bevels 20. The proper shaping is accomplished for the purpose of rendering the blade-advancing members 22 resilient and yieldable. Reference to Figure 3 will show clearly how the depending portions 23 of the seat are concaved outwardly so as to accommodate the lower ends of the spring members 22 and hold such ends in position. V

When the device is employed, the blade is applied to the seat with the bevels 19 sand.- wiched between the blade stops 21. The cover is then swung rearwardly over the blade and blade seat, and pressed downwardly so as to force the blade-advancing members 22 into engagement with the depending portions 23 as shown in Figures 2, 3, and 4. This pressing down of the cover will cause the bladeadvancing members to bear directly against the bevels 20 and wedge the blade forwardly against the blade stops 21. This advancement will position the cutting edge 16 in proper predetermined relationship over the guard edge 11. hen the blade is to be removed or reversed, the cover is momentarily thrown forwardly, thereby making the blade and blade seat accessible.

In Figure 5, I have diagrammatically represented a blade 25 in proper position upon the blade seat of a holder which embodies a modified construction. The blade 25 has opposite cutting edges 26 and 27, side portions 28 converging toward the edge 26, and symmetrically arranged sid-e portions 29 converging toward the edge 27. Beveled blade stops ill are provided which are so positioned as to cooperate with the forward portions of the bevels 28; and blade-advancing members or springs 31, carried by the cover (not shown) bear directly against the bevels 29, but against relatively different portions of these bevels, i. e., that portion of the bevels 28 which is engaged by the stops 30 remains entirely unengaged when the blade is reversed; and correspondingly, those portions of the bevels 29 which are engaged by the springs 31 remain totally unengaged by the blade stops 30. In this way, the total extent of each bevel 28 and 29 has a specific purpose and function and is essential to the proper operation and association of the blade and holder.

In Figure 6, a construction is shown which is similar to Figure 5 vscept that blade stops 32 engage those portions of the bevels 33 which are nearest the center of the blade; and blade-advancing members ill engaging those portions of the bevels which are nearest to the cutting edge 36.

It will be obvious that changes in the details herein described and illustrated for the purpose of explaining the nature of my invention may be made by those skilled in the art without departing from the spirit and scope of the invention as expressed in the appended claims. It is therefore intended that these details be interpreted as illustrative, and not in a limiting sense.

Having thus described my invention and illustrated its use, what I claim as new and desire to secure by Letters Patent is 1. In combination with a wafer-type razor blade having a cutting edge andside edges which converge toward said cutting edge, a razor blade holder comprising a blade seat having a guard edge, means for advancing the blade along said seat and toward said guard edge, and blade stops at the opposite ends of the guard edge and adapted to receive said converging side edges of the blade between them in wedged relationship to limit the advancement of the cutting edge of the blade over said guard edge.

2. F or use with a wafer-type razor blade having beveled side edges, a razor blade holdor comprising a blade seat having a guardedge, blade stops at opposite ends of the guard edge and adapted to receive said beveled side edges of the blade between them in wedged relationship to limit the advancement of the front blade edge over the guard edge, and means engaging said beveled side edges of the blade toward the rear thereof for advancing the blade along said blade seat and toward said guard edge.

3. F or use with a wafer-type razor blade having a front blade edge and beveled side edges, a razor blade holder comprising a blade seat having a guard edge, blade stops at opposite ends of the guard edge and inclined at an angle to said guard edge, said stops being encounterable by the forward portions of said beveled side edges of the blade to limit the advancement of the front blade edge, and means engaging the rear portions of said beveled side edges of the blade for advancing the blade toward said stops.

4-. In combination with a wafer-type razor blade having front and rear blade edges and beveled side edges and being symmetrical about an axis parallel to the front and rear edges, a razor blade holder comprising a blade seat having a. guard edge, inclined blade stops at opposite cues of the guard edge and cncounterable by the beveled side edges of the blade on one side of said axis to limit the advancement of the front blade edge over the guard edge, and means engaging the beveled side edges of the blade on the other side of said axis for advancing the blade toward said stops, whereby the blade is reversible, and whereby the advancement and limit of advancement is effected independently of the front and rear edges of the blade.

5. In combination with a wafer-type blade having a front cutting edge and side edges beveled at their rear ends, a razor blade holder comprising a blade seat having a guard edge, blade stops associated with the guard edge to limit the advancement of the cutting edge thereover, and means engaging said beveled rear ends for advancing said cutting edge, said means comprising angularly disposed spring members adapted to bear directly and yieldably upon said beveled rear ends.

6. In combination with a double-edged wafer-type blade having side edges beveled so as to converge toward each cutting edge, a razor blade holder comprising a blade seat having a guard ed. blade stops associated with the guard edge to limit the advancement of a selected cutting edge thereover, said stops cooperating with the beveled side edges adjacent to said selected cutting edge, and means engaging the beveled side edges adjacent to the inoperative cutting edge for advancing the selected cutting edge over the guard edge and the first mentioned beveled side edges against said stops.

7. In combination with a double-edged wafer-type blade having side edges convergi ng toward each cutting edge, said blade being symmetrical about an axis parallel to the cutting edges, a razor blade holder comprising a blade seat having a guard edge, blade stops associated with the guard edge to limit the advancement of a selected cutting edge thereover, said stops cooperating with a portion of the converging side edges adjacent to said selected cutting edge, and means engaging a relatively different portion of the converging side edges adjacent to the inoperative cutting edge for advancing the selected cutting edge over said guard edge.

8. In combination with a double-edged wafer-type blade having side edges which converge toward each cutting edge, a razor blade holder comprising a blade seat having a guardedge, blade stops associated with the guard edge to limit the advancement of a selected cutting edge thereover, said stops cooperating with the converging side edges adjacent to said selected cutting edge, and

means including obliquely arranged springs for engaging the converging side edges adj acent to the inoperative cutting edge for advancing the selected cutting edge over said guard edge.

9. In combination with a razor blade holder comprising a blade seat, a guard edge on said seat, blade stops associated with said guard edge, and blade-advancing means including angularly disposed members on opposite sides of said seat, a double-edged wafertype blade having side edges converging toward each cutting edge, the converging edges adjacent to one cutting edge being adapted to wedge themselves between said blade stops and the conver ing edges adjacent to the other cutting edge being engageable by said angularly disposed members.

10. In combination with a razor blade holder comprising a blade seat, a guard edge on said seat, blade stops associated with said guard edge, and blade-advancing means including angularly disposed members on opposite sides of said seat, a double-edged wafer-type blade symmetrical about an axis parallel to the cutting edges and having side edges which converge toward each cutting edge, the two sets or" converging side edges being selectively wedged between said blade stops or engaged by said angularly disposed members.

In witness whereof I have signed this specification.

MARCUS B. BEHRMAN.

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