US2409604A - Method of manufacturing safety razor blades - Google Patents

Description

L. A. YQUNG 2,409,304V METHOD 0F MANUFACTURING SAFETY RAZOR BLADS origml med Feb, 14, 1942 NVENTOR. ea/yard H ya' 201g.

Oct. 15, 14946. l L. A. YoUNG 2,409,604

METHOD oF MANUFACTURING SAFETY nAzon BLADES original Filed Feb. 1,4, 1942 2 sheets-sheet 2 za f 3 f; x/ idd 17. EE. ,z5 20 22 v 1 Y Hmmm v//////// E- En.'

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?mw M :L E. i y a Patented Oct. 15, 1946 METHOD OF MANUFACTURING SAFETY RAZOR BLADES Leonard A. Young, Detroit, Mich.

Original application February 14, 1942, Serial No. 430,895. Divided and this application August 2, 1944, Serial No. 547,738

(Cl. 'Z6-104) 3 Claims. 1

This invention relates to a method or process and/or apparatus for manufacturing safety razor blades. The present application is a division of my co-pending application Serial No. 430,895, filed February 14, 1942, Y

One of the objects of the present invention is to provide a method of manufacturing an improved safety razor blade of skeleton form and of the double edge type formed from steel wire of round or other cross section or from a relatively flat or ribbon-like length or piece of steel and having a pair of cutting members or edges of either like size and formation, or one in which one of the cutting members or edges is relatively thinner and more flexible than the other cutting member or edge.

Another object of the invention is to provide a method of manufacturing an improvedsafety razor blade of skeleton form and of the double edge type formed from steel wire or from relatively flat ribbon-like steel stock, in which the blade is capable of fitting a standard safety razor such, for example, as a "Gil1ette type razor.

Another object of the present invention is to provide a method of manufacturing an improved safety razor blade of skeleton form and of the double edge type formed from-steel wire which is capable of tting the standard safety razor such, for example, as a Gillette type razor, and

Another object of the present invention is to provide an improved method and/or apparatus for producing safety razor blades of the foregoing character in which the cutting edges of the blades and the cross members or struts for interconnecting them are formed or fashioned from a single piece of steel wire stock or from a continuous length of flat ribbon-like stock.

Another object` of the present invention is to provide an improved method and/or apparatus for shaping or forming the blade stock into a skeleton type of safety razor blade in which the cutting members or cutting edges thereof are formed or provided in the stock during the step of forming or shaping saidstock into the ultimate blade size, shape and contour.

A further object of the present invention'is to provide improved blades of the foregoing character which are capable of being manufactured according to the present method by quantity production methods at relatively low cost due to the substantial savings in materials over previously known Gillette types of safety razor blades in which solid blanks of steel were employed to make the blades and from which blanks a considerable quantity of the steel was removed by stamping operations, such steel being entirely waste material.

Another object of the present invention is to one in which one of the cutting edges of the 30, provide an improved method and/or apparatus blade is relatively thinner and more flexible than the other cutting edge thereof.

A further object of the invention is to provide a method of manufacturing an improved safety rabor blade of the foregoing type having one j relatively thick and stiff cutting edge and another relatively thinner and more flexible cutting edge whereby` to .provide in one safety razor assembly a relatively stiff cutting member for performing the preliminary or first-over" shavingor cut- 40` ting operation and a relatively thinner and more flexible cutting member or edge for performing the .so-called clean-up or final shaving or cutting operation.

Another object of the present invention is to for manufacturing skeleton type blades of the foregoing character either from steel wire stock of round or other cross section or from relatively flat ribbon-like lengths of steelstock, in which all of the stock is employed in the manufacture ofthe blade with no waste of material dueto punching or stamping out operations resulting in useless scrap.

A further .object of the invention is to provide a method of manufacturing a safety razor blade having a resilient body portion and a contoured cutting edge having a cross-sectional contour comparable tothe cross-sectional contour of a hollow ground blade.

Another object of the invention is to provide an improved method for the manufacture of safety razor blades, in which a blank formed from steel wire stock or from a ribbon-like strip or blank of steel stock is utilized to form the outline and the cutting edge or edges of the blade and in which the cutting edge or edges are formed only inthe work-hardened surface of the steel wire and the blank formed therefrom.

A further object of the present invention is to D provide an improved method of manufacturing safety razor blades which provides a blade which is economical to manufacture and one which is also of superior performance in use.

Another object of the invention is to provide an improved method of makin.Ct safety razor blades in accordance with which each blade may be built up from a plurality of separate pieces but by a process of manufacture which is continuous or substantially continuous.

A further object of the present invention is to provide an improved method of making safety razor blades which eliminates waste of expensive high-grade steel stock caused in conventional methods by the steps of punching or piercing out relatively large portions from the body of the blade.

A further object of the present invention is to provide improved apparatus with the aid of which my improved method may be successfully carried out or executed.

A further object of the present invention is to provide an improved method of making safety razor blades, enabling production of skeleton type blades made from several different kinds of steel in which the cutting edge or edges of the blades are made from high grade steel stock and the cross struts or connecting members are made from relatively low grade steel.

The foregoing and other objects and advantages of the present invention will appear from the following description and appended claims, reference being had to the accompanying drawings forming a part of this specification, wherein like reference characters designate corresponding parts in the several views.

By virtue of the present invention it is possible to form cutting implements, such as safety razor blades, utilizing a metal blank containing a relatively small amount of metal in that the outline of the cutting implement or blade is formed by a wire or ribbon of the metal. As is known, wire contains a work-hardened outer skin which is of more uniform porosity and is harder than the inner or core portion of the wire. the present invention the wire is formed into a blank in any suitable manner, as by means of a press so that the wire, that is the blank into which it is formed, is comparable in shape to the outside rim or outline of the nished blade. The blank is then put through press operations or rolling operations to flatten it out and in one form of the present invention as will be seen hereinafter, one side of the blank can be flattened more than the other side so as to produce a relatively thin and flexible blade portion at one side and a relatively thicker and less iiexible blade or cutting portion at the opposite side. If desired, the wire may be formed into a blank which is thereafter coined or swedged in such a f manner that a work-hardened surface of appreciable thickness is provided on the blank at the thinnest part which forms the final cutting edge of the blade. rlhe cutting edge of the blade is then formed or nished by a honing operation which sharpens the edge thus formed in the work-hardened surface portion of the metal blank.

The improved razor blades and improved processes or methods for manufacturing the same as well as suitable apparatus for producing them are disclosed in the accompanying drawings, in which:

Fig. 1 is a plan view illustrating a part of an improved process or method embodying the pres,-

According to y ent invention and some of the apparatus for carrying out said method.

Fig. 2 is a continuation of Fig. 1; the righthand end of Fig. 1 and the left-hand end of Fig. 2 should be joined to show a continuous method or process. Separation of the method or process into Figs. 1 and 2 was done so as to reduce the length of the figure which could not have been placed in desirable scale on the drawings in a single figure only.

Fig. 3 is an enlarged section taken substantially along the line 3--3 of Fig. l, looking in the direction of the arrows and showing the divided 0r separated blade portions.

Fig. 4 is an enlarged transverse sectional view taken substantially along the line d-fi of Fig. 16, looking in the direction of the arrows.

Fig. 5 is a plan view illustrating a part of another improved process or method embodying the present invention and some of the apparatus for carrying out said method.

Fig. 6 is a plan view illustrating another step in the improved process or method whose preceding steps are illustrated in Fig, 5.

Fig. 7 is a plan view of an improved doubleedged blade embodying one form of the present invention and manufactured by an improved method and/or apparatus embodying said invention.

Fig. 8 is a View similar to Fig. 7 illustrating the preformed or shaped blank as it appears at one stage in the manufacture of the blade of Fig. '7.

Fig. 9 is an enlarged section taken substantially along the line 9 9 of Fig. 8 looking in the direction of the arrows.

Fig. 10 is a transverse sectional view taken substantially along the line l-l of Fig. 7 looking in the direction of the arrows.

Fig. 11 illustrates suitable die apparatus for carrying out one of the steps of an improved method of manufacturing the blade of the preceding views.

Fig. l2 is a plan view of a finished razor blade produced by a further improved method embody ing the present invention.

Fig. 13 is an enlarged transverse section taken substantially along the line iS-ES of Fig. 12, looking in the direction of the arrows.

Fig. 14 is a view similar to Fig. 12 showing the razor blade blank at one stage of the present method or process; and

Fig. 15 illustrates suitable die apparatus for performing a step in the process or method of manufacturing the blade of Figs. 12 and 13.

Figs. 16 and 17 are plan views of razor blades made according to the process shown in Figs. 2 and 5, respectively.

Before explaining in detail the present invention it is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts illustrated in the accompanying drawings, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation, and it is not intended to limit the invention claimed herein beyond the requirements of the prior art.

Method or process a Referring now to Figs. 7 to 11 inclusive of the drawings and in accordance with method or process A, the finished razor blade of double-edged skeleton type, is shown vas a whole at 2B. This blade, as shown, is provided with curved cross struts or interconnecting members 20a. It will be seen that the ends of the original blank have been secured together at 2| by means of welding, or in any other suitable manner, as seen in Fig. 7. As clearly shown, the blade 20 is provided with a cutting edge or member 22 which is relatively thinner and more exible than the opposite cutting edge, member or portion 23, the member 23 being somewhat thicker and less flexible than the blade member 22. This can be seen clearly in Fig. 10.

The process in the present instance, identiiied for convenience as process A, comprises forming the blank 24 from a length of wire of circular or round cross section, which wirey may be passed through, for example, a press (not shown) so as to produce the blank shown in Fig. 8 which is comparable in size to the outline and general contour of the nished blade 20. The blank may be preshaped or formed in other ways, however. After the blank shown in Fig. 8 has been formed, the ends of the wire are secured together at 2li by welding, or in any' other suitable manner. rI'he blank is then placed in a suitable die apparatus such, for example, as the die apparatus comprising a lower die member 21 and an upper die member 28, as shown in Fig. 11. The die members are brought together and the blank of Fig. 8 is transformed into the blank shown in Fig. 10, said blank having a cutting edge or portion at one side, namely the edge 23 which is relatively thicker and less flexible than the cutting edge or portion 22 at the opposite side which is thinner and more flexible than the opposite edge or blade portion 23.

After the finished razor of the form shown at 2U in Fig. 7 is removed from the die apparatus, the cutting edges of the blade are given their final form by a honing operation (not shown) which sharpens the edges thus formed in the work-hardened surface portion of the blank. Thus it will be seen that the method or process A, illustrated in Figs. '7 to 11 of the drawings, constitutes the steps of forming from a length of preferably circular or round cross section wire, a blank which is comparable in shape to the outside rim, outline or contour of the iinished blade, securing the ends of the wire formed blank together after the shaping or forming operation,

attening the wire formed product into a flat shaving blade of skeleton form having two cutting edges, one of the cutting edges being deformed or flattened to a greater extent than the other cutting edge so as to produce a doublei edged razor blade in which one of the cutting edges is thinner and more flexible than the other cutting edge thereof.

Method or process b Referring now particularly to Figs. 1 to4 inclusive of the drawings, there is shown in these figures a somewhat modified and improved method or process and suitable apparatus for carrying out said method, the present method or process being referred to for convenience, as method IIB.

In carrying out the present method I prefer to use stock of high-grade steel in the form of wire, since wire, particularly wire of round cross section, is the cheapest standard stock. The wire which is preferably annealed is fed into `the apparatus continuously from a suitabledrum or reel of wire (not shown). Referring particularly to Fig. 1, the wire stock is indicated as a Whole by the numeral 30 and it is fed from left to right in the schematic illustration of Figs. l and 2. The wire rst passes between a pair of superimposed guide and pressure rollers 40, one such roller being shown. The cross section of the wire 30 is somewhat reduced during its passage between the lrollers 4U and this reduced cross section of the Ytop roller and formed or shaped by the rollers 42 to produce a pair of separated strips or portions 33 and 34. It will be understood that the combined flattening and cutting and shaping rollers 42, one of which is shown, are so ccn-4 structed and arranged as to produce divided strips one of which is thicker and less flexible than the other. For example, the strip or section 33 is relatively thicker and less -iiexible than the strip 34. It will be understood that the shape and size of the divided strips 33 and 34, as well as their diffeernces in flexibility, etc., are determined by the character, size and formation of the rollers 42, as also by the location of the peripheral cutter on the upper roller. Moreover, while I have illustrated rollers 42 for producing strips of different width, thickness and exibility, the rollers can be modified to produce identical strips, if and when desired. l

The divided strips 33 and 34 are thenseparated further apart by suitable means (not shown) and 1 33 and 34 in any suitable manner, as by welding.

Referring now to Fig. 2 of the drawings, the

separated strips 33 and 34 with their fixed bridge pieces orcurved strut members 35, pass into and through a suitable oven 43 to be continuously annealed therein so as to remove the strains produced in the built-up strip or blank because of the welding operation and to soften the welding flash. The built-up strip or blank comprising the portions 33 and 34 and the bridgerpieces or struts 35 is next fed between a pair of superimposed grinding wheels 44, one only being shown, which grind off or remove the welding flash and smooth out any irregularities or burrs which may be present on blank.

From the flash removing cperation at 44, the built-up strip or blank passes toward the right of Fig. 2 until it comes into contact with an automatically operable cutting device 45 which serves to out or sever the iinished blade from the strip.` In Fig. 16 a blade finished or produced in accordance with the method ofFigs. 1 and 2 is shown as a whole at 36, this blade having cutting edges or portions 33 and 34 which are of different degrees of thickness and flexibility as described above. and which are `connected together in Vspaced relation by the iinished bridge `the built-up strip or 7 pieces or cross struts 3l'. After thev blades 36 have issued from the cutting operation, their cutting edges 33 and 3d are given their final form by a suitable honing operation to sharpen these edges which are located in the work-hardened surface portions of the razor blade.

The sectional views of Figs. 3 and 4 relating to method or process B indicate, in somewhat exaggerated manner, the shape and formation of the blade portions 33A and 34 after they issue from the separating and shaping rollers l2 of Fig. 1 and after the blade is separated from the blank as shown at the right of Fig. 2 respectively. Fig. 4 illustrates clearly the differences in the cutting edges 33 and 3d of the nished blade. In Fig. 4 the cutting edge or blade portion 33 is shown as being thicker and narrower than is the opposite cutting blade or portion 3d which, as clearly seen, is wider, thinner and thus more iiexible than the cutting portion or member 33.

With respect to method or process 13, it will be understood that while I have disclosed a certain sequence of steps or operations of my improved method or process, it will be understood that the order of the steps or operations may be changed from that illustrated in the drawings.

Method or process C My improved method. or process designated as process C is illustrated, somewhat schematically, in Figs. 5 andl 6 of the drawings. In accordance with this modied and improved method or process embodying my invention, I conmplate the production of a skeleton type doubleedged razor blade formed from stock of relatively low cost, such as steel wire, preferably of round or circular cross section. One such blade is indicated as a whole by the reference numeral 53 in Fig. 17. The blade 53 comprises cutting edges 55%-, 54, cross struts or bridge pieces 55, 55 which, as shown, are curved to i'lt a standard Gillette type of razor frame, the adjacent end portions of the strut member 55 at the left side of the blade having been secured together by welding, as indicated at E6.

As inY the previously described and illustrated method, designated as method or process B, wire of round cross section shown at Ell in Fig. 5 is fed from a reel or the like (not shown) to a pair of pressure and guide rollers 60. These rollers are preferably superimposed one above the other, only the top roller 69 being illustrated. The wire passes to the right from the pressure and guide rollers 60. During the passage through these rollers the wire 5G is reduced somewhat in cross section, as shown at 5l. The wire 5l then passes through and betwen a pair of superimposed attening rollers El, only the top roller being shown. These rollers serve to flatten the wire, changing its cross section from a circle as Shown at 5l into a rectangle. In other words, the flattening rollers 6l reduce the round Wire 5I to a ilat thin strip 52.

The flat strip of steel stock 52 is now fed into a conventional type of press indicated generally by the reference character 52 in Fig. 5. When the stock issues from the press 62 it will have the shape or formation and outline of the nished razor blade shown in Fig. 17 and designated as a whole by the reference character 52. The step of welding together of the free ends of the left strut or connecting member 55 at point 5S has not been illustrated but it will be understood that this Will likely occur subsequent to the issuance of the shaped blade from the press operation at 62.

The blade 53 is then passed between a pair of superimposed rotating hones 63 and Ell (see Fig. 6) so as to sharpen the cutting edges 54 of the blade. Prior to the sharpening or honing operation and just after the formation of the blade by the press, it will be found that the blade possesses a sharp edge section of work-hardened metal which requires little more than honing and polishing to provide the desired cutting edges thereon. It is not necessary, according to the present invention, to subject the blade 53 to a conventional type of grinding operation which would, in normal operation, remove the workhardened surface portions of the metal. All that is required is a honing and polishing operation which preserves thc Work-hardened surfaces of the metal blank and utilizes it to form the sharp cutting surfaces or edges Ell, 54 of the blade.

After the blades 53 have been honed by the honing members or wheels 63, Gd, they are carried, for example, by an endless conveyor belt 65 into and through a heat treating furnace which is schematically indicated at 66 in Fig. 6 to be continuously heat-treated during their passage through such furnace. The size of the furnace 66 will be determined by the amount of heat treatment to which it is desired to subject the blades 53. After the blades issue from the heat-treating furnace EB, they are in finished form ready to be packaged.

Method or process "D Method or process D embodying the present invention is illustrated in Figs. 12 to 15 inclusive of the drawings. Method or process D is generally similar t0 method or process A previously described, In accordance with process D, it is desirable to produce finished skeleton doubleedged razor blades from steel wire, such as wire of round or circular section. In accordance with the present process, a length of round wire is preferably passed through a press, such as that illustrated at 62 in Fig. 5 of the preceding method or process C, and shaped therein to conform to the outline or finished shape or contour of the finished blade. Such a blank is indicated as a whole at 'lli in Fig. 14. This blank constitutes spaced blade portions in which the cutting edges of the blade are formed, and interconnecting cross struts or bridge pieces 7l. The free ends of the bridge piece 'H at the left of Fig. 14 are secured together at 'l2 by welding, or in any other suitable manner. The blank of Fig. 14 is then placed in a suitable die apparatus such as that shown in Fig. 15 in which the blank is placed between a lower die member 13 and an upper die member 1li, pressure being applied to the blank so as to shape it into the finished blade as indicated as a whole at 'l5 in Figs. 12, 13 and l5. After the blade has been removed from the die apparatus of Fig. 15, all that is necessary to complete it is to subject the cutting edges 'HCS thereof to a honing operation so ,as to produce finished cutting edges in the work-hardened surface metal of the cutting members of the blade.

The purpose of method or process D is to produce a double-edged skeleton type razor blade capable of fitting the Gillette type of razor frame and one in which the cutting edges are identical, and in which said cutting edges are formed in the work hardened surface metal of the blade.

From the foregoing it willbe seen that I have provided several novel methods or processes and suitable apparatus for carrying them out for the purpose of producing skeleton type double-edged razor blades of novel structure. The razor blades produced in accordance with methods or processes identied as A and BV and described above are each provided with a relatively thick and inem'ble cutting edge or portion at one side and a relatively thinner and more flexible cutting edge or portion at the opposite side, The purpose of producing a blade such as that produced by the methods or processes identied as A and 5, is to make available to the users of safety razors, a razor blade which can be used to give, as nearly as possible, the user a shave like he would obtain from a barber. As is well known, the average barber always has used two razors in order to give a customer a clean shave, especially in the event said customer had an unusually tough beard. The barber uses a heavy razor blade for the first shaving operation and then nishes the job with a razor blade which is somewhat lighter and more flexible than the blade of the first mentioned razor. Therefore, by virtue of the present blades of Figs. l and '7, it is possible for the user to employ the heavier and less ilexible cutting edge or blade portion for the first-over shave and then follow up with the opposite cutting edge or blade portion which is relatively thinner and more iiexible for the so-called clean-up shaving operation.

I claim:

1. The method of producing a plurality of razor blades of the double edge type and of skeleton form from a blank of steel wire, which comprises the steps f flattening the wire by rolling continuously into a ribbon-like strip having a thickness substantially corresponding to that of the blades to be produced, longitudinally slitting the strip in two while at the same time forming cutting edge blank portions along the outside edges of the two sections of the strip, separating the strip sections and securing thereto at predetermined points pairs of metal cross struts formed from a lower grade steel, heat treating the attached strips and cross struts, thereafter cutting pieces of predeterthe outside longitudinal edges of the two sections of the strip, moving the strip sections apart and welding pairs of metal cross struts to the separated strip sections at predetermined points, heat treating the attached strips and cross struts, grinding the strip sections and cross struts to remove the welding flash, thereafter severing pieces of predetermined length from the welded together strip sections and struts to provide the nished blades, and thereafter sharpening the said cutting edge blank portions.

3. The method of producing a plurality of razor blades of the double edge type and of skeleton form from a blank of steel wire in which one of the cutting edges of the blade is relatively thicker and stiffer than the other cutting edge, which comprises the steps of rolling the wire continuously to flatten it into a ribbon-like strip, longitudinally slitting the strip into two sections of different widths while at the same time forming cutting edge blank portions along the outside edges of the two sections of the strip in which one cutting portion is relatively thicker and stiffer than the other cutting portion, moving the two strip sections apart, placing pairs of metal cross struts between the separated strip sections and attaching the same to said sections at predetermined points, sharpening the cutting edges on said cutting edge blanks, subjecting the attached strip sections and cross struts to heat treatment, and thereafter severing the sections and cross struts at predetermined points to separate the nished blades from the said strip.

LEONARD A. YOUNG.

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