US3747211A

US3747211A - Safety handle for knives

Info

Publication number: US3747211A
Application number: US00120480A
Authority: US
Inventors: S Hutchinson
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-03-03
Filing date: 1971-03-03
Publication date: 1973-07-24
Anticipated expiration: 1990-07-24

Abstract

A knife of either a fixed blade or folding blade type has an elongated protrusion disposed outwardly from the generally flat back of the handle portion thereof. If the knife is placed on a surface with the sharp edge of its blade dangerously disposed upwardly, with the elongated protrusion from the back of the handle causes the knife to roll onto its side, thereby obviating the dangerous condition. In a folding knife wherein the handle and blade housing are constructed of laminated metal plates, cantalever springs, and spring spacer shims, the protrusion may comprise an enlarged spring spacer shim generally centrally located at the back of the handle. In a fixed blade knife wherein the handle is formed by securing wood, plastic, or the like on both sides of the rearward extension of the blade, the protrusion may comprise an enlargement of the portion of the blade clamped in the handle portin of the knife.

Description

United States Patent 11 1 Calabrese SAFETY HANDLE FOR KNIVES [76] Inventor: Suzanne Hutchinson Calabrese,

19605 SW. 117 Ct., Miami, Fla. 33157 221 Filed: Mar. 3, 1971 21 Appl. No.: 120,480

[52] U.S. Cl. 30/155, 30/296 R [51] Int. Cl. B26b H02 [58] Field of Search 30/155, 286, 290, 30/296 R, 296 A, 156-161, 340

[56] References Cited UNITED STATES PATENTS 701,878 6/1902 Harrison 30/155 2,036,640 4/1936 Lipic 30/155 2,045,192 6/1936 Kuhar..... 30/296 A 2,520,355 8/1950 Bell 30/296 R 3,064,352 11/1962 Koe 30/296 R 903,709 1111908 Guthrie 30/157 1,822,828 9/1931 Stueckman 30/340 X FOREIGN PATENTS 0R APPLICATIONS 8/1966 France .l 30/296 R 1 51 July 24,1973

Primary ExaminerRobert C. Riordon Assistant Examiner-J. C. Peters Att0rney'Mattern, Ware &-Davis [57] ABSTRACT A knife of either a fixed blade or folding blade type has an elongated protrusion disposed outwardly from the generally flat back of the handle portion thereof. 1f the knife is placed on a surface with the sharp edge of its blade dangerously disposed upwardly, with the elongated protrusion from the back of the handle causes the knife to roll onto its side, thereby obviating the dangerous condition.

ln a folding knife wherein the handle and blade housing are constructed of laminated metal plates, cantalever springs, and spring spacer shims, the protrusion may comprise an enlarged spring spacer shim generally centrally located at the back of the handle. In a fixed blade knife wherein the handle is formed by securing wood, plastic, or the like on both sides of the rearward extension of the blade, the protrusion may comprise an enlargement of the portion of the blade clamped in the handle portin of the knife.

4 Claims, 7 Drawing Figures PATENTEU M24373 3. 747. 21 1 INVENTOR. SUZANNE HUTCHINSON CALABRESE MATTERN WARE AND DAVIS ATTORNEYS.

SUMMARY OF THE INVENTION This invention relates to a safety handle for knives,

and more particularly to an improvement in the handle portion of either folding knives or fixed blade knives wherein the knife is provided with an elongated protrusion from the back of the handle portion preventing the knife from resting on a surface with the sharp edge of its blade dangerously disposed upwardly.

Many folding knives, or pocket knives currently in widespread manufacture and use are inherently unsafe. The handle portion of these pocket knives is generally constructed of first two outside handle portions. One or more blades or other tools are pivotally mounted between the outside handle portions at the ends thereof, and the central portion of the handle is hollow to accommodate the blades or tools in their folded positions. The back of the handle, comprising cantalever springs and spring spacer shims is generally flat. This flat portion of the knife handle may be rested upon a flat surface, such as a table, floor, or even a level surface area of ground. When the knife is opened, resting the knife on the flat back surface of the handle portion results in the sharp edge of the blade being dangerously disposed upwardly. If for instance, the knife were placed on the floor or ground, a person could accidently step on the upwardly disposed blade and severly slash the bottom of his foot. Likewise, if the knife is placed on a counter top or work bench in this position, a person could accidently lean on or fall on the exposed blade, again severly cutting his arm or hand.

This dangerous condition also exists in knives of the fixed blade type wherein the back of the handle is sufficiently flat to permit the knife to be rested on a flat surface with the sharp edge of its blade disposed upwardly.

A safety knife handle according to this invention resists being positioned in this dangerous orientation. An elongated protrusion extends outward from the flat surface on the back of the knife handle so that the knife cannot be placed on a flat surface with its sharp edge disposed upwardly. Instead, the knife will automatically tip over, or roll onto its side, thereby presenting only a safe flat side of the blade to the unwary walker.

Accordingly, it is a principal object of this invention to provide a safety knife.

It is a second object of this invention to provide a safety knife which resists being positioned with the sharp edge of its blade dangerously disposed upwardly.

It is an additional object of the invention to provide a safety knife having an elongated protrusion from the handle thereof.

Yet another object of the invention is to provide a safety knife handle of the above type which is easily and inexpensively manufactured.

Other and more specific objects will be apparent from the features, elements, combinations, and operat ing features disclosed in the following detailed description and shown in the drawings.

THE DRAWINGS FIG. 1 is a perspective view of a folding knife according to the invention showing the blades thereof in their closed position.

FIG. 2 is a perspective view of the folding knife of FIG. 1 showing an elongated protrusion from the back surface of the handle portion thereof.

FIG. 3A is an end elevation view of the folding knife of FIG. I placed on a flat surface with its open blade disposed upwardly.

FIG. 3B is an end elevation view of the folding knife of FIG. 1 partially tipped onto its side.

FIG. 3C is an end elevation view of the folding knife of FIG. 1 resting on its side.

FIG. 4 is a side elevation view of the central spacer shim of the knife of FIG. 1; and

FIG. 5 is a perspective view of a fixed blade knife acspring cording to the invention having an elongated protru sion from the back surface of its handle portion.

DETAILED DESCRIPTION ing to the invention and a pocket knife such as is currently in widespread manufacturing use. The two have a substantial number of identical parts.

FIG. 2 is a perspective view showing an elongated protrusion 12 centrally mounted on the generally flat back portion 14 of pocket knife 10, and extending perpendicularly outward therefrom. In FIG. 2 a blade 15 with a sharp edge 16 is shown open. The central portion of the protrusion extends a distance D outwardly from the back portion of the knife. This distance gradually diminishes approaching the ends of the knife. Thus the elongated protrusion 12 has a keel-like shape which tapers down toward the back portion 14 of the knife 10 at either end thereof.

FIG. 3 illustrates the tilting or rolling action caused by the elongated protrusion 12 when the knife is placed on a flat surface such as surface 17 with the sharp edge 16 of blade 15 dangerously disposed upwardly. The bottom surface 13 of the elongated protrusion 12 does not provide sufficient lateral support to maintain the knife in the upright position of FIG. 3A, and the knife tends to tip over in either direction as indicated by

arrows

18 and 20. The bottom surface of the elongated protrusion 13 may be rounded to afford greater comfort to the user of the knife and to further encourage tipping of the knife.

In FIG. 3B the knife is shown in a partially tipped over position and resting on elongated protrusion 12 and on a point 22 of the rounded outside handle portion 23 of the knife. The center of mass of the knife is also indicated in FIG. 3B at 25. The knife will continue to roll into the position illustrated in FIG. 3C if the center of mass 25 is to the right of a vertical line 24 drawn through point 22. The depth D of the elongated protrusion 12 is chosen such that the knife will be sufficiently tipped to satisy that condition for the center of mass.

In FIG. BC the knife has rolled completely onto its side. Thus the sharp edge 16 of open blade 15 points sideways, and only the flat portion of the blade 15 is presented to the unwary walker.

It is not necessary that the protrusion be elongated to cause the desirable tipping or rolling of the knife. A

I FIGS. 1 and 2 is constructed of first two facing steel outside handle portions 23 having plastic or wood insert grips 30. Blades and other tools such as blade 15,

conbination can opener and screw driver 36, and smaller blade 38 are pivotally mounted between the two outside handle portions 23 at the ends thereof. Cantalever springs 40 and 42 are also secured between the two outside handle portions 23, and form a portion of the generally flat back portion 14 of the pocket knife 10. Spring spacer shims 43, 44, and 45 separate the cantalever springs 40 and 42 from each other and from the outside handle portions 23.

It is convenient to form the elongated protrusion 12 by enlarging the central spring spacer shim 44. FIG.'4 shows central spring spacer shim 44 separated from the remaining parts of knife 10. The elongated protrusion 12 appears as an enlargement of this spring spacer shim extending outside the remainder of the pocket knife which is shown by dotted lines 47. The spring spacer shim 44 of FIG. 4 could be easily incorporated into the manufacture of pocket knives without any additional retooling or modification of molds, dies, or production techniques.

The invention is also applicable to fixed blade knives, such as knife 50 of FOG. 5. An elongated protrusion 52 may be formed by enlarging the rearward extension 53 of the blade 54 which is clamped between

outside handle portions

55 and 56. The protrusion 52 insures that the fixed blade knife 50 will also tip and roll onto its side in the same manner described above.

The invention is also applicable to dangerous instruments other than knives which can be rendered more safe by resisting orientation in an unsafe position.

It will thus be seen that the objects set forth above, among those made apparent from the preceding description, are efficiently attained and, since certain changes may be made in the above construction without departing from the scope of the invention, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a limiting sense.

Having described my invention, what I claim as new and desire to secure by Letters Patent is:

l. A tool having a sharp edge and a smooth handle surface opposite the sharp edge on which the tool could rest with the sharp edge dangerously disposed upwardly, the tool comprising a protrusion mounted on the tool upstanding from the smooth handle surface of the tool and remote from the sharp edge thereof, said protrusion extending over substantially the entire length of said handle surface and having sufficient height near the center of the handle surface to cause the tool to tip over when positioned on a flat surface with the sharp edge dangerously disposed upwardly.

2. An improved folding knife of the type comprising outside handle portions, blades and other tools pivotally mounted between the outside handle portion at the ends thereof, cantilever spring means for biasing the blades or other tools in eitheran open or closed position, and spring spacer shims mounted between the cantilever spring means, the cantilever spring means and the spring spacer shim forming a generally flat back handle portion of the folding knife wherein the improvement comprises a protrusion fixedly mounted on and extending substantially the entire length of the flat back handle portion and projecting outwardly therefrom, said protrusion prohibiting the knife from being laid on the flat back handle portion by causing the knife to automatically roll onto either of the outside handle portions.

3. The improved folding knife defined in claim 2 wherein the protrusion comprises an enlargement of a spring spacer shim.

4. The improved folding knife defined in claim 3 wherein the protrusion comprises an enlargement of the most centrally located spring spacer shim.

Claims

1. A tool having a sharp edge and a smooth handle surface opposite the sharp edge on which the tool could rest with the sharp edge dangerously disposed upwardly, the tool comprising a protrusion mounted on the tool upstanding from the smooth handle surface of the tool and remote from the sharp edge thereof, said protrusion extending over substantially the entire length of said handle surface and having sufficient height near the center of the handle surface to cause the tool to tip over when positioned on a flat surface with the sharp edge dangerously disposed upwardly.

2. An improved folding knife of the type comprising outside handle portions, blades and other tools pivotally mounted between the outside handle portion at the ends thereof, cantilever spring means for biasing the blades or other tools in either an open or closed position, and spring spacer shims mounted between the cantilever spring means, the cantilever spring means and the spring spacer shim forming a generally flat back handle portion of the folding knife wherein the improvement comprises a protrusion fixedly mounted on and extending substantially the entire length of the flat back handle portion and projecting outwardly therefrom, said protrusion prohibiting the knife from being laid on the flat back handle portion by causing the knife to automatically roll onto either of the outside handle portions.