US2233445A

US2233445A - Shaving device

Info

Publication number: US2233445A
Application number: US200391A
Authority: US
Inventors: Andis Mathew
Original assignee: Individual
Current assignee: Individual
Priority date: 1938-04-06
Filing date: 1938-04-06
Publication date: 1941-03-04
Anticipated expiration: 1958-03-04

Description

'March 4,1941. M. mms 2233,445

SHAVING DEVICE Filed Apxl 6. 1938 WMM/(W TTO EY- Patented Mar. 4, 1941 2,233,445 sHAvnvG DEVICE Mathew Andis, Racine, Wis.

Application April 6, 1938, Serial No. 200,393.

3 Claims.

'I'his inventionl relates to improvements in shaving devices.

The invention relates more particularly to shaving devices of the type having a reciprocating cutter, driven by an electric motor or other suitable means and movable beneath a slotted face engaging part of fixed blade, whereby the device may be used Without soap or other beardsoftening agent to greatly facilitate the shaving operation.

In devices of this type, shaving is accomplished by a shearing action between the iixed blade and reciprocally movable cutter, and the closeness of the shave depends upon the thinness of the slotted portion of the xed blade. Heretoiore various efforts have been made to obtain the desired thinness at said slotted portion, but several problems have been encountered. First, it is commercially impractical to cut slots in blades formed entirely of extremely thin metal, such as metal of the safety razor blade type; second, even 1 extend inwardly from said edge.

if such slots could be cut, there is the danger of teeth formed in such metal breaking ofi during use; and third there is the difficulty during use, of supporting extremely thin metal against flexing. In the closed type of razor head the metal forming the fixed blade is slotted entirely across the top of the head and is supported against flexing by integral side walls and by the cutter. This permits the use of fairly thin material, but the metal is still too thick to produce the closest type of shave. In other types of shavers a rigid self supporting face engaging membery or fixed blade is employed, and there is therefore no danger of flexing or breaking. However, in this type of construction the metal is usually uniformly tapered to a sharp edge, and the slots This construction is objectionable because unless the hair is cut oil' at the very edge of the member, then it, is not cut off close because of the rapidly increasing thickness of the material which separates the base of the hair from the point of shear. This tapered construction was heretofore considered necessary in a rigid type of blade because with the long slot heretofore employed, the metal had to increase in thickness to furnish the necessary support and to prevent the relatively long teeth from breaking ofi. In all devices where the metal is of uniform thickness throughout the length of the slots, either a desired thinness must be sacrificed or supporting means must be furnished, and as before pointed out even where supporting means is furnished, there is a definite limit to the thinness of material which it is commercially practical to use. For example, in SchickPatentNo. 1,757,978 the thickness is stated as .020 of an inch, whereas this is many times the thickness contemplated and made possible by the present invention.

It is an object of the present invention to provide a shaving device wherein the xed blade is of a rigid self supporting type and wherein said blade departs from standard practice by having an edge ground to uniform Wafer thinness for such a limited distance inwardly that said thin edge cannothex to any objectionable degree,

'there being slots in said edge which preferably terminate approximately at the end of said area of uniform thinness, the material progressively increasing in thickness to furnish support for said extremely thin slotted edge. By having a uniform thinness of material throughout the length of the teeth, a close cut is assured, as distinguished fromfstructures -wherein the thickness of material increases progressively from the edge, and by having the teeth very short, said area of uniform thinness can be obtained without danger of the slotted edge breaking. Furthermore, no extra support is necessary for the teeth because they are too short to flex to any objectionable degree and are well supported by the increased thickness of the remainder of the rigid blade.

While it is preferred to have the teeth of the fixed cutter no longer than the depth of the area of uniform thinness, the results can nevertheless be obtained by other means, such as by having the slots of the reciprocal cutter no longer than the depth of the area of thinness, because with either method cutting must take place at the area of uniform thinness; and the present invention contemplates a very short area of uniform thinness together with means to insure cutting at said area.

A further object of the invention is to provide a shaving device as above described wherein the ends of the slots between teeth in the xed blade terminate at or ahead of the ends of the slots of the reciprocal cutter to hold the hair erect while it is being sheared.

With the above and other objects in view, the invention consists of the improved shaving device and all its parts and combinations as set forth in the claims and all equivalents thereof.

In the accompanying drawing illustrating one complete embodiment of the preferred form of the invention in which the same reference numerals designate the same parts in all of the views:

Fig. l is a side View of a shaving device embodying the improved invention, part of the handle being broken away;

Fig. 2 is a top view of the head showing part Vof the handle attached' thereto;

a hair held erect by the end 60 of the Yslot of the fixed blade by which it is being cut; andv Fig. 6 is a view similar to Fig. 5 showing' an alternative method of insuringfcuttingat the area of uniform thinness. v I

Referring more particularly to the drawing, the numeralV designates a hollow handle portion" formed of any suitable material and forming a. housing 'for an electric motor and associated mechanism utilized to cause reciprocation of a movable cutter 26. The mechanism for driving,

the cutter may be of the type illustrated in copending application Serial No. 124,417, illed February 6, 1937. The handle portion may be closed by a removable cover 21, which cover has its end edgerecessed throughout its length to receive *an elongated strip of felt or other material 28.

The felt may be held in position in the cover by adhesives or any other suitable means. As il lustrated in the drawing, Vthe felt is of suiilcient width so that kit may be bent outwardly beneath the movable cutter 26 to frictionally engage the,

bottom of the same. A seal is thus formed to prevent cut hair from working beneath the cut-v ter into the handle portion.

The xed blade or face engaging member 29 is generally of rectangular outline and is formed for the most part of relatively thick metal whereby the blade is of a rigid self supporting'type.

'Ihe rear portion of the blade is lprovided with a Apair of counter-sunk bolt holes 30 whereby ther member may be secured to the handle by bolts 3|. Intermediate its length the face engaging member is preferably formed with an offset 32, but

' beyond said offset the outer surface is substantially hat as at 33, and slightly converging with respect to the corresponding lower surface 3'4.

Referring now more particularly t0 Fig. 4

which shows on an exaggerated scale the forward portion of the fixed blade, the lower surfaceof i. theblade is ground at an 'angle from'the point to the free edge of the blade. The upper surface is preferably concavely ground from. the

point 36 to the point 31. From the point 31 to the edge the upper surface -is so ground asv to provide a uniform thinness of materialfrom the a point31 to theedge. Said area of uniform thin ness has adepth equal lto the distance (a) and it isV referred that said 'distance be a roxip 'pp i whereby the guard may be adjustably moved to mately .025 of an Yinch and not greater than ..050 of an inch. This uniformly thin area ad-j jacent the edge has teeth 38 cut therein, which teeth are separated by slots 39 which end-at 4Q.: The teeth end approximately at the endiof-fthev area of uniform thinness, and the distance (a) must extend inwardly for such a limited distance' that the very thin edge canlnot flex toyany objectionable degree. By having a uniform thinness of material throughout the length of .the area at which the` hair is cut, acloseout is asp sured as distinguished from structures wherein' the thickness of material increases progressively from lthe edge, and by having the teeth very.

any objectionable degree and are well supported by the increased thickness of the remainder of the rigid blade.

In order to obtain the desired results, the metal at the area (a) has a thickness ofapproximately .0025 of an inch and not greater than .003 of an inch. The pitch of the teeth is approximatelyy .030 of an inch to obtain best results.

The free edge of the movable cutter 28 is formed with a plurality of spaced teeth 4| vseparated by slots which, in the preferred form of the invention, terminate at or behind the ends oi' the slots of the fixed blade as at 42. The teeth 4 1 ofthe cutter are` movable below the teeth 38 of the xed blade 29 and adjacent the free edge thereof. When theelectric motoris energized the movable cutter 26 -is reciprocated at a very rapid rate to cause vshearing of hair extending through the slots 39 of the face engaging member. By having the slots 39 of the fixed blade e at `42' (see Fig. 6) to provide a length nogreater than the depth of the area of uniform thinness of the xed Iblade, the ends 42 serving to holdthe hair erectwhile in the area of uniform thinness and while shearing is taking place.

In orderv to guardl the face from the free edge of the face engaging member and from the movable cutter, it is desirable to` utilize a guard or comb member 44 in advance of the free edge of the face engaging member. A This comb member presents a smooth surface to the face and is preferably slotted as vat 45 by slots which are substantially the same width as the slots 39 of the xedblade and which serve to pick upV and straighten out the hair on the face and guide the same into the slots 39. The teeth between the slots .01" the: comb member have their ends rounded as at 46 to present a. smooth surface to the face. Extending atfsubstantially right angles tend to secure the guard to the handle.' 'I'he openings 48 areof slightly larger 'diameterthan the stemsof the` bolts 49 a's set forth in co-pending application y183,599, flled January 6, 1933,

vary the width ofthe gap between the guard and the edge ofthe xedblade ,and to vary the posttion of the upper edge of the guard with respect,

to the-line b. .The guardgis otherwise formed and constructed in the same manner asset forth in said col-pending application.

n is apparent that .by having the nxed blade"- provided with an edge groundin the manner heretofore described, that extreme thinness may :"be obtainedthroughout the length-of the teeth in va structure utllizingarigid type, self supporting iixed blade. As/a result gf-the wafer thln` ness of the material separating the base of the hair from the point of shear, throughout the length of the teeth of the fixed blade, an extremely close cut is assured.'

This construction may be utilized inconnection with a single edge shaving device as illustrated, or in connection with double edge shaving device such as the one shown in Figs. 11 to 22 of copending application 185,599.

While the teeth 38 of the fixedv blade may extend inwardly beyond Lthe area of uniform thinness, such greater length would serve no useful purpose, it being the concept of thepresent invention to have an area of uniform thinness which extends inwardly for such a limited distance that the material cannot flex, in combination with a shearing cooperation between the teeth of the cutter and the ilxed blade which lnsures cutting only at said area of uniform thinness, and this can be accomplished either by having the slots of the fixed blade of no greater length than the depth of the area of uniform thinness as in Fig. 5, or by having the slots of the cutter of no greater length than the depth of said area as in Fig. 6.

Although only two forms of the invention have been shown and described, it is obvious that various changes and modifications may be made without departing from the spirit of the invention, and all of such changes are contemplated as may come within the scope of the claims.

What I claim is:

1. In a shaving device having a reciprocally movable cutter member provided with slots, an outer blade member mounted above said cutter, means connected to a portion oi' said blade for supporting the blade against movement, said blade having a free edge portion. projecting beyond the supporting means, and said projecting portion being of suillcient thickness and rigidity throughout the major portion of its length to support itself against flexing, said outer blade member having an outer surface portion adjacent said free edge ground concavely to gradually ta' per the thickness of the metal to not greater than .003 of an inch and having a portion of uniform thinness not greater than .003 of an inch extending outwardly from said concavely ground portion, said portion of uniform thinness having slots positioned over the slots of the cutter member and extending over such a limited distance 'toward the free edge of the blade, not greater than .050 of an inch, that the teeth of said uniformly thin slotted portion will not break during normal use in spite of the thinness of said portion.

2. In a shaving device having a-reciprocally movable cutter member provided with slots, an

outer blade member mounted above said cutter, means connected to a portion of said blade for supporting the Vblade against movement, said blade having a free edge portion projecting beyond the supporting means, and said projecting portion being of sufficient thickness and rigidity throughout the major portion of its length to support itself against iiexing, said outer blade member having' an outer surface portion adiacent said free edge ground concavely to gradually taper the thickness of the metal to not greater than .003 of an inch and having a portion of uniform thinness not greater than .003 oi an inch extending outwardly from said concavely ground portion, said portion of uniform thinness having slots positioned over the slots of the cutter member and extending over such a limited distance toward the free edge of the blade, not greater than .050 of an inch, that the teeth of said uniformly thin slotted portion will not break during normal use in spite of the thinness of said portion, the slots of said outer blade member being of no greater length than the depth of said area of uniform thinness to insure' all shearing of hair taking place in said area.

3. In a shaving device having a reciprocally movable cutter member provided with slots, an outer blade member mounted above said cutter, means connected to a portion of said blade for supporting the blade against movement, said blade having a free edge portion projecting beyond the supporting means, and said projecting portion being of sufiicient thickness and rigidity throughout the major portion of its length to support itself against flexing, said outer blade member having an outer surface portion adjacent said iree edge ground concavely and having a lower surface portion ground on a plane disposed at an angle to gradually taper the thickness oi.' thefmetal to minimum thinness and having a portion of uniform thinness equal to said minimum extending outwardly from said concavely ground portion,v the upper surface of said