US1802289A

US1802289A - Razor blade

Info

Publication number: US1802289A
Application number: US460012A
Authority: US
Inventors: Swan Arthur Ernest
Original assignee: Individual
Current assignee: Individual
Priority date: 1930-06-09
Filing date: 1930-06-09
Publication date: 1931-04-21
Anticipated expiration: 1948-04-21

Description

April A N RAZOR BLADE Filed June 9, 1930 Jwomtoz- Patented Apr. 21, 1931 PATENT OFFICE AIR-THUR ERNEST SWAN, OF NEW YORK, N. Y.

RAZOR BLADE Application filed June 9,

The present invention relates to razor blades, and more particularly to that type of razor blades commonly known as the safety razor blades, which are made of sheets of steel. Such blades are of two general types, namely the flexible type which is adapted to be flexed or bowed when mounted in the holder, and the rigid type which is adapted to retain substantially its original position when mounted in the holder. In both of these types, however, the blade must possess a. predetermined amount.

of rigidity and resistance to deformation in order to be capable of use.

Herctofore the rigidity of these blades has been primarily dependent upon their thickness, for steel of givenquality, and

"the minimum thickness of sheet material from which a blade could be made depended primarily upon the rigidity and resistance to deformation of a flat sheet of: such steel having the surface dimensions of the blade.

Double edged blades having a. single groove or ridge running longitudinally of the blade midway between its cutting edges have. been proposed, but the principal purpose of the groove in such blades has been to facilitate the handling of the blade in the course of its manufacture. Such a groove does not act to materially assist the blade in resisting deformation upon application of forces at the corners or along the edges of the blade and a blade provided with such a groove would have to be made of' material of substantially the same thickness as a flat blade. A- general object of the present invention is the provision of a thin type blade having the qualities of resistance to deformation, rigidity, and cutting power heretofore "ob- 40 tainable only in a blade of greater thickness. Another object of the invention is the provision of such a blade which will resist longitudinal Warping along its cutting edges and thus prevent cracking. A further object of the invention is the 1930. Serial No. 46Q,012.

provision of such a blade which will have an increased range of adjnstability when mounted within the holder, and till another object is the provision of such a blade which will be heldsccurely in the holder regardless of its adjustment. 'lhcse and other objects ofthe invention will become more readily apparent upon a. detailed study of theaccompanying drawings and specification in connection with the appended claims. 7

in the drawings, Figs. 1', 2 and 3 are side elevations of various blades formed in accordance with my invention;

Fig. l is an end elevation of the blades shown in Figs. 1, 2 and 3.

Figs. 5 and bare end elevations of modilications of the blades shown in Figs. 1-4;

and

Figs. T and S are side elevations of blades made in accordance with the present invention and mounted in standard type holders.

As shown in Figs. 1, 2 and 2'), the invention may be embodied in blades 2 having any of'the standard type openings 4 "for mounting the blades in conventional holders (5 or 8. Each oi the blades is corrugated as shown in Fig. -l and thereby provided with alternating ridges on either side of the blade. The depressions and ridges of the corrugations run parallel with the cutting edges l2 and lengthwise of the blade. These corrugations preferably extend as closely as possible to the cutting edges in order to strengthen the blade against longitudinal warping at the cutting edges. In the modification shown in Fig. -l, the portions 14; of the blade 2, upon which are formed the cutting edges 12, he in a plane passing between the crests of the alternate ridges 10.

i It will be observed that the blade shown in Fig. 3 has two cutting edge portions, which are separated longitudinally by a slot and are connected at their ends by flexing hinge portions which are located beyond the cutting edge portions. When in a holder, the hinge portions are flexed transversely. The longitudinal corrugations in the hinge portions enable the same to flex readily and without undue stress. The longitudinal corrugations in the cutting edge portions still'en the same against warping and preclude. the presentation of a warped or wavy cutting edge when the blade is clan'iped in a holder. The separation of the cutting edge portions by a longitudinal slot greatly weakens their resistance to deformation during the shaving operation and where ordinary flat blades of'this type are used they are apt to crack it not clamped very tightly in the holder. Thus no or practically no adjustment can be obtained with a flat blade of this type whereas a corrugated one greatly facilitates the range of adjustment even beyond that obtained with a Hat ilexible blade whose cutting portions are not separated by a longitudinal slot. In the case of a flat blade there is a limit to the thickness because of the necessity of preserving the transverse flexibility. \Vhere the blade is longitudinally corrugated, the necessary .transvcrse flexibility can be maintained with much thicker metal.

In the modification shown in Fig. 5, the portions 14.- of the blade 16 lie in a plane passing through the crests of the ridges 10 formed on one side of the blade only, while in Fig. 6 the corrugations are substantially rectangular in shape.

Due to the presence of the corrugations in the blades shown in Figs. 1 to 6, these blades have great ability to resist deformation alon their cutting edges and it is there fore possible to manufacture the blades of thinner sheet material than was heretofore possible. The blades will be found to pos sess ri idity and cutting power of blades heretoibre made of thicker sheet material.

In the conventional holders for blades of the general type disclosed in Figs. 1 to 3, there is a handle member 20 having a head portion 22 and an overlying clamp member 24, the blade being adapted to be secured between the head portion and the clamp member. The blade is. ordinarily adjusted by tightening or loosening the connection be tween the head portion and clamp member, and where the usual type of blade is employed, the holder consequently. does not grip the blade very tightly in some stages of the adjustment.

When blades made in accordance with my invention are inserted in the holder, they otter a resilient resistance to the clamping action of the clamp member due to the presence of the corrugations, and there is therefore a constant grip of the holder on the blade whether the holder be screwed up tifghtly or loosely. Moreover, compression 0 the blade between the members of the holder will result in an elongation of the corrugations and a widening of the blade. Thus it is possible to obtain a wide range of adjustment of the blade by merely tightening and loosening the holder.

It will, of course, be understood that any suitable number of corrugations or channels may be formed in accordance with the particular type of holder in which the blades are adapted to be used, but the corrugations should lie as close to the cutting edges of the blade as is practicably possible.

lVhile I have shown the invention as applied to only a few types of blades and holders, the invention is nevertheless capable of a wide application to any other form of holder and blade.

Having now described my invention, what I claim as new and desire to secure by Letters Patent of the United States is as follows 1. A double edged safety razor blade adapted to be flexed into a position of transverse curvature by the clamping action of a holder, said blade being of sheet metal bent to present in unrestrained position a cross-section in which both cutting edges and their immediately adjacent blade portions are substantially in a single plane and in which the entire central blade portion lying between the blade portions immediately adjacent the cutting edges presents a substantially sinuous curve having a plu rality of crests lying outside the plane of the cutting edges whereby the transverse flexibility and the longitudinal stiffness of the blade are increased.

2. A safety razor blade adapted to be flexed transversely by the clampin action of a holder, said blade being provi ed with reentrant recesses each located at one of .its corner portions and having cutting edge portions separated longitudinally by a slot and connected at their ends by flexing hinge portions which are located beyond the cutting edge portions, said cutting edge portions and said flexing hinge portions being longitudinally corrugated to stiffen the cutting edge portions longitudinally and to increase the transverse flexibility of the hinge portions, whereby said blade is capable of ready transverse flexin Without. longitudinal deformation under t e clamps ing action of a holder.

3. A safety razor blade adapted to be flexed transversely by the clampin action of a holder, said blade being rovi ed with reentrant recesses each locate at one of its corner portions and havin cutting edge portions separated longitudinally by a slot and connected at their ends by flexing hinge portions located beyond the cutting edge portions, said cutting edge portions and the portions of said flexing hinge portions in alignment with the cutting edge portions being longitudinally corrugated to stiffen the cutting edge portions longitudinally and to increase the hinge portions transverse flexibility of the whereby said blade is caset my signatur ERNEST SWAN.