US3325897A - Safety scissors - Google Patents

Description

June 20, 1967 5. c. LUEBKEMAN SAFETY SCISSORS 2 Sheets-Sheet 1 Filed Dec. 2, 1963 Egg? INVENTOR George Clucblfeman J1me 1967 G. c. LUEBKEMAN 3,325,397

SAFETY SCISSORS Filed Dec. 2, 1963 2 Sheets-Sheet 2 INVENTOR. Georye Claehieman ATrY.

United States ?atet1t G 3,325,897 SAFETY SQISSORS George C. Luebheman, 214 Cherokee Ave, incinnati, Ohio 45223 Filed Dec. 2, 1963, Ser. No. 327,255 8 Claims. (Cl. 30-254) The present invention relates to novel safety scissors and is particularly directed to safety scissors provided with automatically operable means that will render the scissors inoperative to cut objects of harder compositions than that of its predetermined, rated capacity.

It is therefore an object of the invention to provide a pair of safety scissors that will normally cut materials having relatively low shear indexes, such as paper, human hair or some light weight, woven, fabrics, and which has a yieldable means in at least one handle portion that will flex to render the scissors inoperative upon the application of a cutting pressure that would cut objects of relatively higher shear indexes such as metal, human skin, and the like.

Another object of the invention is to provide in a safety scissors having the foregoing characteristics, simplified yet rugged yieldable means that will give long and depend able services.

Other objects will become apparent from the following specification taken in conjunction with the accompanying drawings, wherein like reference numerals indicate identical parts throughout the several views:

FIG. 1 is a plan view of one form of my safety scissors, the dotted lines therein illustrating the flexed position of one handle thereof.

FIG. 2 is a greatly enlarged, cross-sectional view taken on line 22 of FIG. 1.

FIG. 3 is a fragmental, plan view of a modified form of fiexbile handle means for my safety scissors.

FIG. 4 is a greatly enlarged section taken on line 44 of FIG. 3.

FIGS. 5 and 6 are fragmental, perspective views of further modifications of flexible handle means for my safety scissors FIG. 7 is a fragmental, plan view of a still further modified form of my safety scissors.

FIG. 8 is an enlarged section taken on line 88 of FIG. 7.

FIG. 9 is a fragmental, plan view of still another modified form of flexible handle means for my safety scissors.

FIG. 10 is a plan view of another modified form of my safety scissors.

FIG. 11 is a greatly enlarged, cross sectional view taken on line 1111 of the FIG. 10.

FIG. 12 is a view similar to FIG. 11, illustrating the spring adjustment in its operative position.

Now with particular reference to FIGS. 1 and 2 of the drawings, the safety scissors illustrated therein comprises two blades 10 and 11 each having a cutting portion 12 and 13, respectively, that are disposed in face-to-face relationship so that the opposed edges may be moved on an object to be cut by the pair of scissors. The cutting portion 13 has an integral first handle portion 14 thereon while a composite second handle portion 15 is associated with the cutting portion 12, said composite handle portion 15 consisting of a tang 16 integral with the cutting portion 12 and a handle 17. Pivot means 18 connects the blades 10 and 11 between the cutting portions 12 and 13 and their respective tang and handle portion. As best shown in FIG. 2 the confronting, adjacent ends of the tang 16 and the handle 17 of the second handle portion 15 are in spaced apart relation, the handle 17 forming an elongation of the tang 16. The tang 16 and the handle 17 are connected together by a yieldable connection which takes the form of a cylindrically shaped, helical spring 19, the inner end coils 20 of the spring being tightly wound on the tang and preferably aflixed to said tang by a plastic cement, or the like. The opposite end coils 21 of the spring 19 are tightly wound on the handle 17 and may be also afiixed to the handle by a suitable plastic cement, or the like.

The scissors blades 10 and 11 are provided with a stop means fixing their fully opened position, said means comprising an arcuate slot formed in the tang portion 16 on the radius of the scissors pivot means 18 and a pin anchored in the first handle portion 14 and projecting into the slot 100. When the scissors is in its fully opened position depicted in FIG. 1 the pin 110 will limit further opening movement of the blades by engaging the body of the tang at the left hand end of the slot 100; the pin moving freely in the slot as the blades move from the fully opened positions to their fully closed positions.

When it is desired to cut a material for which the safety scissors was originally designed, the handles 14 and 17 are manipulated back and forth relative to one another in the usual manner which alternately brings the blades 10 and 11 together and moves them apart to thereby cut the material presented between their cutting edges. However, when a foreign object of a harder composition than the material designed to be cut by the safety scissors is presented between the blades 10 and 11 and the handles pressed together in the usual manner, the yield point of the spring 19 will be surpassed, the spring will flex and the handles will move together whilst the blades remain in a stationary, non-cutting position with respect to the foreign object. Thus the yieldable means will preclude operation of the scissors on foreign objects that are harder than the designed cutting capacity of the safety scissors.

My scissors is particularly useful as childrens play scissors in that the scissors may be constructed to cut paper or light textile fabrics but will be incapable of cutting the childs fingers. Also the scissors may be used by either children or adults as hair trimmers in that the spring could be given a yield point which would provide for normal cutting movements of the scissors when used to sever human hair, but would flex when the human flesh was presented between the cutting blades. The cutting portions 12 and 13 may have rounded or blunted ends and 130, respectively, to further increase the safety factor of the pair of scissors.

Referring now to FIGS. 3 and 4 of the drawings there is shown a modified form of yieldable means for the composite second handle portion 15 of my safety scissors, said means comprising a helical spring that has cylindrically shaped inner end coils 200 encircling the tang 16 and aflixed thereto by plastic cement 201. The opposite end coils 210 of the spring are cylindrically shaped and encircle the handle portion 17, said coils being afiixed to the handle by plastic cement 211. The intermediate coils 191 of the spring 190 are elliptically shaped in section and are disposed on the handle 17 such that their long elliptical axes are transverse of the plane of cutting movement of the scissors blades to offer relatively great resistance to spring deformation in that direction whilst the short elliptical axes of the intermediate coils are parallel to the cutting movement of the blades and offer less resistance to deformation in that direction.

With reference to FIG. 5 of the drawings there is shown another modified form of the yieldable means for my safety scissors which comprises a flexible metal strip 22 that has one end 23 press fitted into a slot 24 formed in the end of the tang 16 of a pair of scissors like that shown in FIGS. 1 and 2 of the drawings, the opposed end 25 of said flexible metal strip 22 being press fitted into a slot 26 formed in the adjacent end of the handle 17. This yieldable means has the advantage of being flexible in the direction of the plane of movement of the scissors handles whilst being practically inflexible laterally of said plane of movement.

Now with reference to FIG. 6 of the drawings there is shown a further modified form of my yieldable means for my safety scissors depicted in FIGS. 1 and 2 thereof, said yieldable means consisting of a flexible metal strip 27 having a pair of opposed integral tabs 28-28 formed on one end thereof which are crimped around the end of the tang 16 of the scissors, the opposed end of the strip having an integral pair of opposed tabs ES -29 crimped around the adjacent end of the handle 17 of said scissors. This form of yieldable means may be made from a metal stamping and the central strip portion only tempered, the crimped ends of said strip being additional affixed to the ends of the tang 16 and the handle17 by plastic cement, or the like; if desired.

In FIGS. 7 and 8 of the drawings there is shown a still further modification of my invention wherein the numeral 30 indicates a first handle portion of a pair of scissors which is integral with a cutting portion 31, the other cutting portion 32 being integral with a tang 33. A second composite handle portion 34 has a handle 35 that forms an elongation of the tang 33 and has its end spaced away from the end of the tang. A yieldable means, such as a coil spring 36 has one end 37 encircling and aflixed to the end of the tang 33, while the other end 38 of the spring encircles and is afiixed to the adjacent end of the handle 35. The end 37 of the spring 36 is formed to provide a hook 39 (FIG. 8) which projects laterally from the tang and engages the first handle portion 30 when the scissors is in fully opened position. The first handle portion therefore moves freely of the hook 36; said hook providing a stop means limiting relative opening movement of the scissors handles and also its cutting blades. The handle portions for my safety scissors are relatively long as compared to at least the cutting portions of the blades that are adjacent the pivot thus giving the scissors handles a long leverage or mechanical advantage with respect to said cutting portions that materially increases the shearing force exerted by the handles on said cutting portions. My yieldable means is therefore combined with a means that limits the maximum shearing force which can be exerted by the handles on the cutting portions of the blades by the provision of a positive stop means limiting relative opening movement of the scissors blades.

Referring to FIG. 9 of the drawing there is shown still another modification of a yieldable means for the second handle portion of my safety scissors, such means comprising a pivotal connection 40 between the overlapping ends of the tang 16 and the handle 17 of the scissors. A straight piece of spring wire 41 extends across the pivotal connection 40 and has its inner end 43 tightly wound or otherwise affixed to the tang whilst its opposed end 44 is tightly wound on the handle 17 FIGS. 10l2, inclusive, of the drawings depict another modified form of my yieldable means for safety scissors wherein said means is made adjustable to provide several cutting capacities for a single pair of scissors. The safety scissors shown in said figures has two cutting blades 50 and 51 that are disposed in face-to-face relation whereby the opposed edges may be moved on an object to be cut by the pair of scissors. The cutting blade 51 has an integral first handle portion 52 while a composite second handle portion 53 is connected with the cutting blade 50; said composite handle portion 53 having a tang 54 integral with the cutting blade 50 and a handle 55. Pivot means 540 connects the cutting blade 50 and and with particular reference to FIG. 1] the confronting, adjacent end portions of the tang 54 and the handle 55 are in spaced apart relationship and are each provided with external threads 56 and 570, respectively. The tang 54,

and the handle 55 are connected together by a yieldable connection which takes the form of a cylindrically shaped,

helical spring 57, the inner end coils of the spring being tightly engaged in the thread 56 on the tang 54 and preferably affixed to said tang by a plastic cement, or the like. The opposite end coils of the spring 57 are tightly engaged in the thread 57a on the handle 55 and are also affixed to the handle by suitable cement, or the like.

An auxiliary, cylindrically shaped helical spring 58, having a greater diameter than the connecting spring 57, is adapted for threaded engagement in the spiral trough formed externally on the spring 57, said spring 58 having its inner end turned outwardly at 5 to provide a tab that may be manually grasped for rotating said spring 58 around the connecting spring 57.

With particular reference to FIG. 11 of the drawings it will be noted that the auxiliary spring 58 has its inner end engaged only around the inner portion of the spring 57 so that the effective length of the spring 58 does not span the gap between the tang 54 and the handle 55 of the scissors. When the scissors is used with the said auxiliary spring in its retracted position only the connecting spring 57 will yield when a foreign object is inserted between the blades and 51 of the scissors, whereby an object of relatively low shear index may be cut by the scissors without operation of the yieldable means. When an object with a higher shear index is to be cut by the scissors the tab 59 is grasped and the auxiliary spring 58 threaded onto the spring 57 to the position indicated in FIG. 12 so that both springs span the gap between the tang 54 and handle of the scissors. Thus the object of higher shear index may be cut with the scissors but said scissors will still yield to foreign objects which may come between the blades 50 and 51 that have a shear index harder than the combined capacity of the two springs.

Having thus described my invention what I claim as new is:

1. A pair of safety scissors comprising two blades, each having a cutting portion, a first handle portion integral with the cutting portion of one blade, a tang integral on the other blade, pivot means connecting the blades between the cutting portions and their respective tang and handle portion, a second handle portion forming an elongation of the tang, and a yieldable connection between the adjacent ends of the tang and the second handle portion, said yieldable connection being adapted to operatively connect the tang to the second handle portion for normal cutting operations of the scissors and flexible upon the application of abnormal cutting pressures on said handles.

2. A pair of safety scissors as set forth in claim 1 characterized by the fact that the yieldable connection comprises a helical spring having one end encircling and aflixed to the tang and having its opposite end encircling and affixed to the second handle portion.

3. A pair of safety scissors as set forth in claim. 1 characterized by the fact that the yieldable connection comprises a flexible strip having one end press fitted in the body of the tang and its opposed end press fitted in the body of the second handle portion.

4. A pair of safety scissors as set forth in claim I characterized by the fact that the yieldable connection comprises a flexible strip having one end crimped around the tang and the opposite end crirnped around the second handle portion.

5. A pair of safety scissors as set forth in claim 1 characterized by the fact that the second handle portion and the tang are pivoted together and the yieldable connection comprises a flexible wire extending across the pivot and having one end fixed to the tang and the other end fixed to the second handle portion.

6. A pair of safety scissors comprising two blades each having a cutting portion, a first handle portion integral with the cutting portion of one blade, 21 tang integral with the other blade, pivot means connecting the blades between the cutting portions and their respective handle portion and tang, a second handle spaced from and forming an elongation of the tang, a yieldable connection between the adjacent ends of the tang and the second handle portion, said yieldable connection being adapted to operatively connect the tang to the second handle portion for normal opening and closing cutting operations of the scissors blades, said yieldable connection being flexible upon the application of abnormal cutting pressures on the handles, and stop means interposed between the first handle portion and the tang for limiting relative opening movement of the blades.

7. A pair of safety scissors comprising two blades each having a cutting portion, a first handle portion integral with the cutting portion of one blade, a tang integral on the other blade, pivot means connecting the blades between the cutting portions and their respective handle portion and tang, a second handle spaced from and forming an elongation of the tang, a coil spring operatively connecting the tang to the second handle, one end of said spring encircling and aflixed to the tang and the opposed 20 end of the spring encircling and afiixed to the second handle, and a laterally projecting hook formed on the spring and engaging the first handle portion to provide a stop means limiting relative opening movement of the blades.

8. A pair of safety scissors comprising two blades each having a cutting portion, a first handle portion integral with cutting portion of one blade, a tang integral on the other blade, pivot means connecting the blades between the cutting portions and their respective handle portion and tang, a second handle spaced from and forming an elongation of the tang, a coil spring operatively connecting the tang to the second handle, one end of said spring encircling and aflixed to the tang and the opposed end of the spring encircling and affixed to the second handle, and an auxiliary spring threaded on the coil spring and adapted for adjustment between an inoperative position encircling only one end of said coil spring and an operative position encircling and coextensive with said coil spring.

References Cited UNITED STATES PATENTS 371,756 10/1887 Henry 30262 X 2,965,967 12/1960 Wahl 30341 WILLIAM FELDMAN, Primary Examiner.

JAMES L. JONES, Examiner.

25 I. C. PETERS, Assistant Examiner.

Claims (1)

1. A PAIR OF SAFETY SCISSORS COMPRISING TWO BLADES, EACH HAVING A CUTTING PORTION, A FIRST HANDLE PORTION INTEGRAL WITH THE CUTTING PORTION OF ONE BLADE, A TANGE INTEGRAL ON THE OTHER BLADE, PIVOT MEANS CONNECTING THE BLADES BETWEEN THE CUTTING PORTIONS AND THEIR RESPECTIVE TANG AND HANDLE PORTION, A SECOND HANDLE PORTION FORMING AN ELONGATION OF THE TANG, AND A YIELDABLE CONNECTION BETWEEN THE ADJACENT ENDS OF THE TANG AND THE SECOND HANDLE PORTION, SAID YIELDABLE CONNECTION BEING ADAPTED TO OPERATIVELY CONNECT THE TANG TO THE SECOND HANDLE PORTION FOR NORMAL CUTTING OPERATIONS OF THE SCISSORS AND FLEXIBLE UPON THE APPLICATION OF ABNORMAL CUTTING PRESSURES ON SAID HANDLES.

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