US2009402A

US2009402A - Safety razor

Info

Publication number: US2009402A
Application number: US629870A
Authority: US
Inventors: Johnston Howard Addison
Original assignee: Individual
Current assignee: Individual
Priority date: 1932-08-22
Filing date: 1932-08-22
Publication date: 1935-07-30
Anticipated expiration: 1952-07-30

Description

July 30, 1935- H. A. .JOHNSTON 2,009,402

' SAFETY RAZOR Filed Aug. 22, 1932 a 422%@ A@ i ml-ll 1i-5.12. i

UT'Ueh for' Joh 5 V011 Patented July 30, 1935 NT oFFicEgf 1 SAFETY-RAZOR Howard Addison Johnston, Toronto, ontario,

Canada Application August 22, 1932, serial No. 629,870 8 Claims. `(Cl. 30V-12) This invention relates to safety razors,.an'd more particularly to that type in which a double edged flexible blade is clamped between a convex base plate and a concave cover plate. My object is to provide a razor in which the blade may be removed or replaced in an instant when so desired, but of such design that the blade cannot become loose accidently by any amount of shaking suchas occurs when the razor is rinsed after using and is shaken to remove the surplus Water. Blades which are gripped by frictional devices holding one end of the blade sometimes loosen and fall out when vigorously shaken, due to the centrifugal forces developed by the movef ment, and the turning moment resulting frornthe gripping of the blade at a point distance from its centre of gravity.`

I attain my object by providing a blade holder with a winged stud, and the blade with a central opening which will .freely admit the stud and the wings when the blade is turned to a transverse position in relation to the holder. When the blade is placed over the stud and rotated about it, the wings engage the central portion of the blade, pressing it toward the holder and retaining it in that position. When the blade has been rotated about ninety degrees it reaches its shaving position and is locked there as follows: I provide openings in the blade at a distance from the cen'- ter, and projections on the holder which enter the openings in the' blade when it has reached the desired position. At the beginning of. rotation of `the blade about the stud the center of the blade is pressed toward the face of the holder by the spiral action of the wings, but the'end portions of the blade are prevented from moving in the same direction because they are riding on the top of the aforesaid projections. These projections are diametrically opposite each other and are provided with a positive stop on the side to which the blade is being rotated and an easy slope on the opposite side.

As the blade is rotated farther about the stud, the openings in it are brought into register with the projections on the holder, whereby the trailin'g'edge of each opening springs into engagement withV the positive stop on the corresponding pro'- jection, thus preventing any further rotation.

The leading edge of the opening, at the same time, engages the adjacent easy slope, and since no Y y y v"l, which projects from the upper surfaceV thereof.

rotation of the blade in the `opposite direction can take-place without springingthe blade upward against the slope, .the trailing edgel of the opening is held closely against the positive stop .until it is intentionally removed. Y

position without the blade;

lwith the free end ofthe base The constructions are hereinafter more fully described and are illustrated inthe accompanying drawing.

In the drawing likeY numbers of reference indicate corresponding parts in the different figures. Fig. 1 is a side elevation of. the razor in'open Fig. 2 a side elevation of the razor in closed Yposition with the blade in shaving position;

l Fig. 3 a section on line 3, 3 in Fig. 2;Y

Fig. 4 a section on

line

4, 4 in Fig. 15; y Fig. 5 an enlarged 'side elevation of blade holder and blade; n

Fig. 6 an enlarged section on

line

6, 6 in Fig. 5; Fig.- 6a an enlarged section on line 6,'6 in Fig. 5, but with the blade-in shaving position; y

' Fig. 7 an enlarged plan view of the blade holder; Fig.8 a longitudinal section of the holder in Fig. 7;v l

Fig 9 an enlarged section on line 9, 9 in Fig. 8,; Fig; 10 a plan view of the preferred form of blade; Y

Figs. 11 and 12 vplan Views of modified forms of my blade; y Y Y Fig. 13 a plan view of another modification of my blade; K v

Fig. 14 an enlarged plan View of the preferred form of blade locked on the holder in shaving position; .and Fig. 15 a section on the longitudinal centerline of the razor in closed position, without the blade,

a handle I which is attached to a base plate `2,0n

which is hingeda cover `plate 3. The blade 4 is carried by a holder 5 which is hingedly'mounted on the pintle of the rst mentioned hinge to lie betweenthe plates 2 and 3. The double hinge connection comprises a pintle carried by spaced lugs 2i o n the base plate 2.Y The blade holder 5 is provided-With two bent down bearing flanges 5f which are 'disposed on the pintle between Vthe lugs 2a, and the cover plate is provided with a hinge knuckle 3a also disposedon the pintle, be- ,s

tween the bearing flanges 5f.t I providea spring latch 8, pivoted at 9 onthe free end of the cover plate 3, adapted to be sprung into engagement plater2, to lock the razor in-shaving position. l Y Y K I provide the blade holder 5 with a short stud vstruction isitoailx` a stamped metal winged cap 'lb to the top of the short stud 1, as shown in Fig. 8. The blade holder 5 is also provided with projections 'c each of which has a substantially perpendicular face 5d on one side and an easy slope 5e on the other side. The blade holder is preferably formed by stampingit from sheet metal, thus providing the bearing and stifening flanges 5f, the projections 5, the short stud 1, and the slightly raised surface 5g with one operation. l

The base plate 2 is made with a longitudinal channel 2b into which the blade holder isY received when the razor is closed. The blade holder is made to t the inside of the channel andso prevent any lateral movement of the holder and blade when in the closed position as shown inv Fig. 3.

The portion of the upper surface/of the bladeholder 5 which is adjacent to the stud 1, is raised` slightly above the surrounding general surface asshown at 5g, Fig. 5,-so that when the center ofV the lblade r#1 ispresseddown by the lower part of the wings '121, the end portions ofthe blade will be engaged. by the sloping face 5S- of the projections -5c before coming into contact with thegeneral vsur'jface ofk the holder as shown in Fig. 6a.

I provide the razor blade 4 with asymmetrical opening 4a, transverse to the longitudinal axis of the blade, which opening may or may not be connected to` other openings extending along the longitudinal 'center line. .The preferred form consists of a small central opening lla and two diametrically opposite openings 4f communicating with-opposite Aends of the central opening 4a which extends transversely across the blade betweenthe openings 4f. The distance between 'the outer edges of the openings flfnon, a line transverse to the longitudinal center line of theblade is greater than the width of the transverse opening 4a. The length of the said openings 4f in a direction parallel to the said longitudinal center line is alsogreater thanthe width of the transverse opening 4e. The preferred form of the opening formedY bythe openings 4b, 4a, 4f may be described as resembling in shape the longitudinal section-of adumbbell, or the central portion and twoopposite wings of a maltese cross. The opening is designed to permit the passage of the stud 1 and the Wings 'lci when the blade is turned transverse to the holder. By reason of the fact that the parts of the opening .distant from the center are larger than the central portion of the. opening, lugs 4 are formed on the blade projecting toward thecenter of the opening. These` lugs are made to terminate at 'equal distances from the center of the' blade, and give a bearing surface on the stud I when the blade isrplaced thereon. l

`Other openings 4b Vare provided lying symmetrically on the longitudinal center line of the blade at a distance from the center.- The opposite sides of these openings, have inwardly directed lingers or

shoulders

4d and 4e projecting towards one another and adapted to engage the vYacesSd and 5e of the projections `5c whenw the blade is in shaving position.

The cover plate3 is provided with a projection -3b on its concave side1 which is adapted to pass Startins with the razor; ingopen. position as shown in Fig. 1 the opening 4a in the blade 4 is passed over the stud 'l and its wings 'la while the blade is held in a position transverse to the holder. The blade is then rotated about the stud 'l in a counter-clockwise direction. The turned up edges of the wings la first make contact with the lugs 4C formed on the blade. As the blade is rotated further the central portion of it is sprung toward the body of the holder by the screw action of the wings le, and the portions of the bladeA distant from the center ride on the projections 5C carried by the holder, whereby the blade is dished longitudinally.

. When the blade has been turned approximately VVninety degrees, that is when its longitudinal cen- 6b followy down the easy slopes 5e of the projections 56 thereby bringing the other shoulders or lingers d on the trailing edges of the opening into contact with the positive stops 5d which prevents further motion in this direction of rotation. The pressure o1 the wings 'la on the central portion of the blade tends to flex the blade longitudinally, whereby the shoulders or lingers 4c are held in yielding engagement with the sloping faces 5e and the .shoulders or iingers id are drawn toward and held in contact with the stops 5d, as long as the blade remains in the holder. By forming the fingers 4d and le as previously described, greater flexibility of these fingers is obtained whereby any inaccuracies in the formationl of the sloping faces 5C will be compensated by the deflection of the flexible fingers without distorting the blade as .a whole. The blade is now in shaving position on the holder as shown in Fig. 14.

The cover plate 3 is now moved to its closed `lifted from the holder.

It will be obvious that the exact form ofthe blade retaining means, and the exact form of the opening in the razor blade is unhniportant in the application of this principle of blade retention. It is necessary only that the opening in the blade and the retaining surfaces be complementary to each other, and that while allowing free passage in one position, no passage is allowed when the blade is rotated. It is of material advantage for ease in placing the blade that the spiral, or screw form of blade retainer be used, but it is not essential. 1t should be understood therefore, that the invention is not limited to the exact details described, as many variations may be made by those skilled in the art without departing from the spirit of the invention.

What I claim as my invention is: 1. A Ysafety razor having a carrier adapted to carry a blade having a non-circular opening therein; a blade retaining device adapted to pass Vthrough the said opening in the blade to engage the' margin thereof `upon a turning movement of the blade relative to the device; anda projection on the carrier having two faces opposite one another, one of the Vsaid faces being substantially normal to the surface ofthe carrier 'and the v other-,fa'.cey being inclined to the s'aid'surface in the direction 'of turning of;the blade, the said faces being adapted to be engaged by two shoulders spaced apart on the blade to tend to hold the blade from turning relative to the device, the engagement of the shoulder and inclined face resulting in the other shoulder being held against the other face.

2. A safety razor having a blade carrier provided with a centrally located raised surface for supporting a blade in spaced relationship to the surfaces underlying the blade at the end portions of the carrier, the blade having a non-circular opening therein; a blade retaining device adapted to pass through the said opening in the blade to engage the margin thereof upon a turning movement of the blade relative to the device; and projections on the end portions of the carrier, each projection having two faces opposite one another, one of the said faces being substantially normal to the aforesaid surface of an end portion and the other face being inclined to the last mentioned surface in the direction of turning of the blade, the said faces on each projection being adapted to be engaged by two shoulders spaced apart on the blade, the shoulders in engagement with the inclined faces being located above the aforesaid surfaces of the end portions of the carrier so that they tend to hold the other shoulders in contact with the normal faces.

3. A safety razor having a carrier adapted to carry a blade having a non-circular opening therein; a blade retaining device adapted to pass through the said opening in the blade to engage the margin thereof upon a turning movement of the blade relative to the device; and projections on the carrier at opposite sides of the retaining device, each projection having two faces opposite one another, one of the said faces being substantially normal to the surface of the carrier and the other face being inclined to the said surface in the direction of turning of the blade, the said faces on each projection being adapted to be engaged by two shoulders spaced apart on the blade, the underside of the retaining device being helically inclined at one end thereof, the bottom of the inclination being below the tops of the projections so that the blade is moved to a position below the tops of the projections and the engagement between the shoulders and the inclined faces tends to hold the other shoulders in contact with the normal faces.

4. A safety razor provided with a blade carrier having a central fixed stud; and two diametrically opposed wings in fixed relationship to the stud and extending lengthwise of the carrier in spaced relation to its adjacent surface, the under surface of each wing being inclined adjacent one side thereof to facilitate the engagement of the wing over a razor blade apertured in correspondence with the stud and wings and which is adapted to be positioned thereover and then rotated.

5. A safety razor provided with a blade carrier having a central fixed stud; two diametrically opposed wings in fixed relationship to the stud and extending lengthwise of the carrier in spaced relation to its adjacent surface, the under surface of leach Wing being inclined adjacent one side thereof to facilitate the engagement of the wing over a razor blade apertured in correspondence with the stud and wings, and which is adapted to be positioned thereover and then rotated; and a. projection from the surface of the carrier adapted to spring into an opening in a razor blade to tend to resist a rotary movement of the blade relative to the holder.

6. The combination with a carrier asset forth in claim 4, of a razor blade having a, central opening formed therein shaped as a double keyhole slot with its axis at right angles to the length of the blade, the central portion of which is shaped to form a bearing for the stud of the carrier while the enlarged portions of the slot are positioned diametrically opposite one another transversely of the blade, the said enlarged portions serving for the passage of the wings only when the blade is substantially at right angles to the carrier.

7. The combination with a. carrier as set forth in claim 4, of a razor blade having a central opening formed therein shaped as a double keyhole slot with its axis at right angles to the length of the blade, the central portion of which is shaped to form a bearing for the stud of the carrier while the enlarged portions of the slot are positioned diametrically opposite one another transversely of the blade, the said enlarged portions serving for the passage of the wings only when the blade is substantially at right angles to the carrier, the blade having a hole formed therein towards one end adapted to engage the projection on the carrier.

8. A safety razor having a, carrier adapted to carry a flexible blade; projections on the carrier having inclined faces on which edges of openings in the blade are adapted to rest; a blade retaining device located between the projections on the carrier and adapted to pass through a non-circular opening in the blade to engage the margin of the said non-circular opening upon a relative turning movement of the blade and device, the underside of the device being helically inclined to ex the blade toward the carrier during said turning movementl while the blade is being passed over the projections, the bottom of the said inclined underside being below the tops of the projections so that the blade will spring into locking engagement with the projections when the said openings are brought into register therewith.

HOWARD ADDISON JOHNSTON.