US3378922A

US3378922A - Disposable safety razor

Info

Publication number: US3378922A
Application number: US463189A
Authority: US
Inventors: Clarence O Schrader; James L Marcotte
Original assignee: Eversharp Inc
Current assignee: Eversharp Inc
Priority date: 1965-06-11
Filing date: 1965-06-11
Publication date: 1968-04-23
Anticipated expiration: 1985-04-23
Also published as: GB1130977A; BE682340A; DK119915B; NL6608092A; SE308460B; NO119974B

Description

c. o. SCHRADER ET AL 3,378,922

April 23, 1968 DI SPOSABLE SAFTY RAZOR 2 Sheets-Sheet 1 Filed June 11, 1965 INVENTORS T W s AC W MM T CM 1A h m mm M "U M {or C April 23, 1968 c. SCHRADER ET AL 3,378,922

DISPOSABLE SAFTY RAZOR Filed June 11, 1965 2 Sheets-Sheet 2 Q 26 33 INVENTORS 1: CLARE/216k; 0. SCHgADERg 7: 3o M L.MA COTT %wsl BY 23%}, W

32 M @wg; ATT'YS.

United States Patent 3,378,922 DISPOSABLE SAFETY RAZOR (Ilarence O. Schrader, Sherman Oaks, and James L. Marcotte. Torrance, Calif., assignors to Eversharp, Inc., Milford, Conn., a corporation of Delaware Filed June 11, 1965, Ser. No. 463,189

12 Claims. (Cl. 30-66) ABSTRACT OF THE DISCLOSURE A disposable plastic razor of the double edge type formed from three molded pieces consisting of a handle, frame and cap. The frame has guard bars and a blade seat which supports a conventional double edge razor blade. The clamped condition of the blade may be visually determined because the cap is formed of clear plastic. The parts are assembled by placing the blade seat in the handle and then inserting an integral stem on the cap into the handle through the frame, causing expansion of a boss on the frame, disposed within the handle to lock the parts together and, if desired, the frame and cap may be also heat staked. The junction of the frame and cap is readily frangible to permit easy destruction of the razor to preclude further use.

This invention relates to safety razors in general and more specificially is directed to a new and improved safety razor of pre-assembled design which may be discarded after use or at such time when the useful life of the razor blade has been completed.

In its broadest sense, the safety razor of the present invention includes a novelly and economically constructed handle, frame and cap assembly which on assembly cooperate to clamp a razor blade of conventional design. Suitable means is provided to retain the parts in assembled relation once assembled, with additional means provided to preclude indestructible disassembly. The razor may be disposed of or discarded when no longer usable and is provided with a frangible area which permits it to be easily fractured or destroyed to preclude further use.

The pre-assembled razor of the present invention finds particular application in hospitals, medical treatment centers and the like where sanitation and sterility of the blade and razor is of utmost importance. Due to the economy of the construction, the present safety razor may also be sold in transportation terminals, used as a guest razor in the home or the like, to mention a few of the many other uses. While the safety razor of the present design is very accurate, it is relatively inexpensive permitting it to be discarded when it has fulfilled its function.

A greater appreciation of the salient features of the present invention may be had by consideration of the objects achieved and a description of a preferred form of the invention.

It is an object of this invention to provide a new and improved safety razor.

It is a further object of this invention to provide a new and improved safety razor of a novel construction which lends itself to economical manufacture and is relatively inexpensive permitting application where the razor may be disposed of after it has served its purpose.

It is a further object of this invention to provide a new and improved pre-assembled razor provided with a frangible area to permit easy destruction before disposal to preclude further use.

It is a still further object of this invention to provide a new and improved razor construction having a novel means to facilitate quick and easy assembly of the cap, frame, razor blade, and handle.

Additional objects will become apparent when reference is made to the accompanying drawing wherein:

FIG. 1 is a perspective view of the razor of the present invention with the protective sleeve removed and shown in perspective also;

FIG. 2 is a top plan view of the frame which supports the razor blade;

FIG. 3 is a cross sectional view taken generally along the lines 3-3 of FIG. 2;

FIG. 4 is a cross sectional view taken generally along the lines 4-4 of FIG. 2;

FIG. 5 is a side elevational view of the cap;

FIG. 6 is a cross sectional view of the cap, frame and handle shown fragmentarily in an intermediate step of assembly;

FIG. 7 is a view similar to FIG. 6 wherein the component parts have been assembled;

FIG. 8 is a bottom plan view of the frame on a reduced scale taken generally along lines 8-8 of FIG. 7;

FIG. 9 is a fragmentary enlarged cross sectional view taken along the lines 99 of FIG. 8 and showing the heat staked portion of the spider; and

FIG. 10 is a side elevational view of the razor of FIG. 1 with the handle shown in cross section and the razor head fractured along the predetermined frangible area.

The razor assembly 11 includes basic elements consisting of a handle 12, a frame member 13, and cap 14. All of these elements may be formed from known types of plastic by known molding techniques. The cap 14 may be formed of clear transparent plastic, and co-operates with the frame 13 to clamp a razor blade 15 with the marginal edges exposed to permit shaving.

The razor assembly 11 of FIG. 1 is illustrated in the assembled condition ready for marketing. A sleeve-like protective guard 16 has a box-like opening 17 and a V- shaped slot 18 extending inwardly from one edge and terminating in a circular opening larger than the inner end of the slot. This facilitates the easy placement of the sleeve over the razor head 20 to serve as a protective cover during shipment and prior to and after use. The slot 18 at its inner end in the protective sleeve is smaller than the upper part of the handle 12 to retain the sleeve 16 when the razor is not in use.

Referring to FIGS. 2-4, the details of the frame 13 will be described. The frame 13 includes a main body 21 having raised side

marginal portions

22 and 23 which serve to support the razor blade 15 at the appropriate angle when clamped by the cap 14. A longitudinal groove 24 is disposed centrally of the body portion and merges with a generally circular opening 25 at the center of the main body 21 of the frame 13.

Concentrically disposed about the opening 25 is an annular raised boss 26 which projects perpendicularly from the underside of the frame 13. The boss 26 extends upwardly from the main body 21 and necks in forming a radial shoulder 27 which shoulder terminates at an axially extending cylindrical or tubular portion 28 of the boss 26 which is of substantial length. An annular stepped bore 30 is formed within the raised boss 26, and at its outer end merges through a frusto-conical portion 31 into a section of reduced diameter 32 which projects radially inwardly towards the axis of the bore. The shoulder 27 provides a section of reduced diameter or frangible area to permit fracture of the boss to separate the parts when the razor is no longer usable.

A pair of

runner members

33 and 34 are provided on opposite sides of the longitudinal groove 24 for longitudinal rigidity. As seen in FIG. 3, at opposite ends the runner 33 intersects depending flanges v35 and 36 which provide transverse rigidity to the frame along the opposite ends.

Outwardly of the blade supporting marginal

inclined portions

22 and 23 is provided a series of teeth or

serrations

37 and 38 respectively which function as a guard to uniformly align the flesh while the razor is performing a cutting action. The rounded outer margins of the

teeth

37 and 38 serve to assist in guiding the razor in its travel over the cutting area.

Disposed on opposite sides of the longitudinal groove 24 are raised

knobs

40 and 41 which support the razor blade 15 at the center and also serve as a guide to align the cap with the frame during assembly as will be seen.

As seen in FIGS. and 6, the cap 14 is provided with an arcuate top 42 which terminates at opposite margins on the underside in inclined

blade clamping portions

43 and 44. The inclined blade clamping surfaces or

portions

43 and 44 are formed to co-operate with the

blade clamping surfaces

22 and 23 on the frame 13. Centrally of the cap 14 is provided a spindle or stem 45. The free end of the stem 45 is formed with a frusto-conical section 46 tapering inwardly to a reduced diameter portion to provide a guiding surface for use in assembly.

Longitudinally aligned

spider members

47 and 48 are formed on opposite sides of the stem 45 and extend along the underside of the cap 14. The

spider members

47 and 48 have a combined longitudinal dimension which is slightly less than that of the groove 24. The lower edge of each spider member is transversely tapered as at 49 and 50 to enhance the assembly into the groove 24. Straight or untapered areas are provided at 51 and 52 for heat staking the spider members to the frame after assembly.

As seen in FIG. 6, the handle 12 is provided with a stepped bore 52a, generally consisting of an entrance bore 53 joined by a frusto-conical section 54 to an enlarged bore 55 which extends the length of the handle 12.

In assembling the razor, the cylindrical portion 28 on the frame 13 is positioned within the bore 53 and the shoulder 27 brought into engagement with the end 56 of the handle 12. The axial dimension of the cylindrical portion 28 of the boss 26 is such that the end thereof projects beyond the terminal point of the bore 53 in the handle 12.

The razor blade may be assembled onto the cap so that the slotted portion is recevied by the

spiders

47 and 48 and the stem 45 is then inserted into the bore of the raised boss 26. The frusto-conical end 46 on the stem 45 is brought into engagement with the frusto-conical portion 31 at the lower end of the bore 30 and the parts assume the relationship shown in FIG. 6. During this stage of assembly, the knobs 41 not only support the razor blade 15 but also co-operate with the tapered edges of the

spiders

47 and 48 to enhance the ease of alignment of the cap 14, blade 15 and frame 13.

At this step of assembly, all the parts are readily separable. Application of a downward force to the cap 14 and an oppositely directed force to the handle 12 causes the tapered portion 46 on the stem 45 of the cap 14 to enter and expand the lower or radially inwardly projecting shoulder at the lower end of the bore 30. This may cause partial fracture of the circumferential portion 28 or merely cause it to expand. In either event, the parts assume the relationship shown in FIG. 7 with the reduced portion 32 of the bore being radially expanded to the position shown at 58.

During this operation, the knobs and 41 have held the central portion of the razor blade 15 at one elevation while the clamping or

blade engaging surfaces

43 and 44 on the cap have acted against the razor blade 15 to bring the marginal edges down into engagement with the

inclined portions

22 and 23 on the frame 13. The

spider members

47 and 48 enter the longitudinal groove 24 in the frame and the razor blade is tightly clamped with the opposite cutting edges exposed immediately above the

teeth

37 and 38 on the frame. Passage of the stem through the reduced bore 32 causes expansion of the lower end of the circumferential portion 28 into the configuration generally shown at 58 and exerts a reverse gripping or constricting action on the stem to resist withdrawal. The expanded end of the circumferential barrel portion 28 locks the frame to the handle in a very positive manner.

In order to further prevent separation of the cap 14 and frame 13, the

straight sections

50 and 51 on each of the

spiders

47 and 48 may be heat staked as shown in FIG. 8 to form a little button or

enlargement

61 and 62. The approximate form of this button is best seen in the cross sectional view of FIG. 9 overlapping opposite sides of the groove 24. In this manner the cap is precluded from withdrawal from the frame and the frame is held against removal from the handle 12. At this stage, the unitized assembly is incapable of disassembly without damaging at least one of the parts.

As pointed out above, the raised

knobs

40 and 41 on opposite sides of the groove 24 serve to provide a support or fulcrum to engage the razor blade at the center. This reduces the load forces on the frame 13 and cap 14 in the clamping area when the blade is bowed or clamped. Such reduction in force increases the shelf life of the razor which would normally be adversely affected by the cold flow inherent in plastic if the center support or its equivalent were omitted.

Since the cap 14 is formed of clear plastic, the grip or clamping action on the razor blade by the cap along the opposite marginal edges may be visually inspected as the area of contact is readily visible. Continuous clamping action adjacent the blade edges is important if a comfortable shave is to be obtained without injury to the skin. The remaining parts of the razor are also illustrated as being formed of plastic material and it is contemplated that any type of opaque plastic which is conducive to high speed molding techniques may be used. Other materials which will perform equivalent functions may be substituted.

After the heat staking is complete, the protective sleeve 16 may be placed on the shaving razor head 20 and the razor is ready for shipment or sale. When the razor is to be used, the protective sleeve 16 may be laterally withdrawn as the inner ends of the V-shaped groove are flexible, and the razor is ready for immediate use. In preparing patients for operations, suturing wounds and the like, the surrounding area of the wound or incision is shaved. After the shaving operation is complete, the present razor may be discarded. If for sanitary reasons, it is desired that the razor is not to be further used, even though usable, application of pressure by the thumb under the frame 13 causes the razor head 20 to fracture at the juncture of the end 56 of the handle adjacent the shoulder 27 on the boss 26. Disposability and destruction of the razor is especially important Where the patient shaved has a contagious disease. The razor head 20 is easily broken away from the handle by force application in the direction of the arrows in FIG. 10 permitting easy and efficient destruction to preclude further use. If desired, the protective sleeve may be replaced to protect against injury.

The minimum number of parts and simplified design of the present razor adds to the ease of manufacture at a reduced cost with the several parts performing multiple functions. Notwithstanding its economical manufacture, the razor may be made to extremely accurate tolerances to provide maximum shaving comfort when assembled with a blade. The protective sleeve permits the razor to be sold without a special case or the like, further reducing the cost to the consumer.

After a consideration of the foregoing it will become obvious to those skilled in the art that various modifications may be made without departing from the inventive concepts embodied herein. Therefore, only such limitations should be imposed as are indicated by the spirit and scope of the appended claims.

We claim:

1. In a safety razor having a handle, frame and cap, and wherein said cap and frame are adapted to clamp a razor blade for shaving, the improvement comprising means to join said handle, frame and cap, said means including a bore in said handle, a boss on said frame said boss including a bore therethrough, said boos being positioned in said bore in said handle, and stem means on said cap extending through said bore in said boss and fastening said boss in place within said bore in said handle and simultaneously clamping said razor blade, thereby to retain said handle, frame and cap in assembled relation.

2. The improvement in safety razors of claim 1 which further includes at least one opening means in said frame, fastener means, including a shank portion extending downwardly through said opening means, said fastener means further including an enlarged head portion of larger diameter than said opening means, thereby fastening said cap means to said frame means.

3. The safety razor of claim 1 wherein said cap is formed of clear plastic to permit visual determination if said cap is in clamping contact with said razor blade.

4. A pre-assembled safety razor comprising a handle with a bore having a step therein, a frame having inclined blade supporting portions on one side and a raised boss on the opposite side, said raised boss on said frame being received in said stepped bore in said handle, said raised boss being provided with a longitudinal bore and with an outwardly extending flange at the outer end thereof, a cap for clamping a razor blade to said inclined portions on said frame, said cap being provided with a stern depending from the underside thereof, said stern being received in said bore in said boss, said stem preventing inward movement of said flange and holding said flange in locked position engaged with said step in said bore thereby to lock said frame and handle together, and means joining said cap to said frame to prevent withdrawal of said stem.

5. The safety razor of claim 4 wherein said means joining said cap to said frame to prevent withdrawal of said stem includes oppositely extending spider members on said cap, said spider members being received in a longitudinal groove in said frame and having a portion thereof deformed to preclude withdrawal of said spider members from said groove.

6. The safety razor of claim 4 wherein said boss is provided with a radial shoulder forming a frangible section to permit fracture separation of said cap and frame from said handle and thereby destroy said safety razor to preclude further use.

7. A safety razor comprising a handle having a bore at one end, a portion of said bore in said handle remote from said end being enlarged relative to that immediately adjacent said end, a blade supporting frame having a longitudinally extending slot in a central portion, said frame having inclined portions adjacent opposite marginal edges to support opposite marginal edges of a razor blade, a raised boss formed centrally of said frame on a side opposite said inclined portions, said raised boss having a longitudinally extending bore therethrough terminating at one end in a portion of reduced diameter relative to the remainder of said bore, said raised boss being receivable in said bore in said handle, and a cap having means thereon to expand the reduced portion of said bore in said boss radially outwardly into the enlarged portion of said bore in said handle to lock said cap means, frame and handle together while simultaneously clamping said razor blade into shaving relation on said frame, said cap being provided with longitudinally extending spiders adapted to project through said longitudinally extending slot in said frame, each of said spiders having a portion thereof deformed to preclude withdrawal from said slot.

8. A three-piece safety razor adapted to be preassembled to clamp a razor blade for shaving, said safety razor comprising a handle having a longitudinal bore, said longitudinal bore in said handle being of reduced diameter adjacent one end, a frame having a raised boss thereon, said raised boss having a radial shoulder portion and an axially extending cylindrical portion, a longitudinal bore through said boss having one end thereof of a reduced diameter relative to the remainder of said bore, means on said frame for supporting said razor blade, a cap having a spindle thereon of a diameter slightly less than the diameter of said longitudinal bore in said boss but greater than the diameter of said reduced portion of said last mentioned bore, said cylindrical portion of said boss having an outside diameter approximately equal to the diameter of said reduced diameter portion of said longitudinal bore in said handle, said cylindrical portion being radially expanded when said spindle passes through said reduced portion in said longitudinal bore in said boss thereby to join said cap, frame and handle while simultaneously clamping said razor blade for shaving.

9. The safety razor of claim 8 including additional means to join said cap and frame to preclude indestructible disassembly.

10. A safety razor comprising a handle having a bore at one end, a portion of said bore in said handle remote from said end being enlarged relative to that immediately adjacent said end, a blade supporting frame having a longitudinally extending slot in a central portion, said frame having inclined portions adjacent opposite marginal edges to support opposite marginal edges of a razor blade, knob-like means adjacent said slot for supporting a central portion of said razor blade, a raised boss formed centrally of said frame on a side opposite said inclined portions, said raised boss having a longitudinally extending bore therethrough terminating at one end in a portion of reduced diameter relative to the remainder of said bore, said raised boss being receivable in said bore and said handle, and a cap having means thereon to expand the reduced portion of said bore in said boss radially outwardly into the enlarged portion of said bore in said handle to lock said cap means, frame and handle together while simultaneously clamping said razor blade into shaving relation on said frame.

11. A preassembled safety razor adapted to be discarded after use, said razor comprising, in combination, a handle including a first and a second. bore therein, said first bore extending inwardly from the top of said handle and said second bore being a continuation thereof, and having a larger diameter than said first bore, and, communicating with said first bore at a bore step, a frame member having means thereon for supporting a razor blade, boss means on said frame member, said boss means including a bore therethrough and an annular flange at the bottom of said boss, said flange being engaged with said bore step, and cap means for clamping said razor blade to said frame, said cap means including stem means extending through said bore in said boss means and holding said flange outwardly against said bore step and said boss means outwardly against said first bore, whereby said cap and said frame are held in locked position in relation to said handle.

12. The safety razor of claim 11 which further includes at least one opening means in said frame, fastener means, including a shank portion extending downwardly through said opening means, said fastener means further including an enlarged head portion of larger diameter than said opening means, thereby fastening said cap means to said frame means.

References Cited UNITED STATES PATENTS 1,103,904 7/1914 McCain 30-50 1,602,613 10/1926 Hoffman 30-72 X 1,879,900 9/1932 Hofmann 30- 68 X 1,879,961 9/1932 Thompson 30-73 (Gther references on following page) UNITED 7 STATES PATENTS Hueber 3090 Benjamin 30-65 Lewando 3064 X Robinson 3032 Landwehr 30-64 Meohas 3032 Curtis 3090 8 3,229,367 1/1966 Lewis 3069 3,277,571 10/ 1966 Bloomfield 30-90 FOREIGN PATENTS 870,960 1/ 1942 France. 392,701 5/1933 Great Britain. 599,290 3/1948 Great Britain.

MYRON C. KRUSE, Primary Examiner.