US2985480A

US2985480A - Sling

Info

Publication number: US2985480A
Application number: US714386A
Authority: US
Inventors: John A Otley
Original assignee: Individual
Current assignee: Individual
Priority date: 1958-02-10
Filing date: 1958-02-10
Publication date: 1961-05-23
Anticipated expiration: 1978-05-23

Description

J. A. OTLEY May 23, 1961 SLING 2 Sheets-Sheet I.

Filed Feb. l0, 1958 May 23, 1961 J. A. oTLEY 2,985,480

SLING Filed Feb. lo, 195s 2 sheets-sheet 2 INVENTOR.

JOHN H. O TLEV i@ am@ SLING John A. Otley, 4620 Moran, Detroit 7, Mich.

Filed Feb. 10, 1958, Ser. No. 714,386

13 Claims. (Cl. 294-74) This invention relates to an improved load-carrying sling.

Heretofore slings have been made primarily of rope, such as manila rope, and cable. When slings of this construction are used to lift, for example, copper tubing, or other materials which may be easily marred or defaced, it is diicult if not impossible to altogether prevent defacement of the material without padding the sling.

As a result, it is a primary object of the instant invention to provide a sling which, without additional padding, may be used to handle articles that are easily scratched' marred, or defaced without danger of such occurring.

Another object of the invention is the provision of a sling which has a longer useful life than a comparable rope or cable type of sling.

A further object of the invention is the provision of a sling made from a at band of material such as webbing wherein the webbing or band is folded longitudinally upon itself in a novel fashion to provide eyes at opposite ends, with the construction being such that the plies cornprising the sling Alock themselves against relative shiftable movement tending to unwind the sling when the sling is subjected to a stretching tension. The band may be stitched or otherwise secured together to hold the laminations or plies of the sling together between lifting operations. With ,the construction of the sling being such that the plies of the band tend to lock themselves against relative shifting when a stretching tension is applied to the sling, the stitching need not be relied upon to carry the .load supported by the sling but serves only to integrate the sling between lifting operations.

Still another object of the invention is the provision of a self-locking type of band sling comprising a single band folded to provide two or more plies, the outer plies serving to take the brunt of operation during use of the sling while the inner plies serve to cushion or absorb shock and blows during use of the sling.

A still further object of the invention is the provision of a sling formed of a band wherein the opposite free ends of the band are hidden between laminations or plies of the sling so that they are not subject to catching on the material being lifted or on the floor on which the material normally rests either during the lifting operation, during the insertion of the sling beneath the material, or as the sling is forcibly withdrawn from beneath the material. Opposite free ends of the band are hidden between larninations of the sling by virtue of one ply or lamination being carried by a half turn over another ply or lamination.

Other objects, advantages, and meritorious features will more fully appear fromy the specification, claims, and accompanying drawing, wherein:

Fig. l is a perspective view of one form of a sling ernbodying my invention;

Fig. 2 is a perspective view of another form of the invention;

Fig. 3 is a perspective view of a sling wherein only one end of the barid is tucked inside the sling, the opposite end lying outside the sling.

Fig. 4 is a View of the half turn of one layer or ply Patented May 23, 1951 of the band carrying it over an adjacent ply looking in the direction of arrow 4 in Fig. 1;

Fig. 5 is across sectional view taken on the line 5-5 of Fig. 1;

Fig. 6 is a perspective view of an endless sling with opposite ends of the band being tucked inside the sling;

Fig. 7 is a perspective view of still another form of the sling;

Fig. 8 is a perspective view of another form of the sling made of two pieces of webbing; and

Fig. 9 is an end View looking in the direction of arrow 9 in Fig. 8.

A typical embodiment of the invention is shown in Fig. l. It comprises an elongate band folded longitudinally upon itself to provide a multiply loop (a loop formed of a plurality of plies) which is flattened throughout an intermediate portion of its length to provide eyes at opposite ends. The eyes are indicated at 10 and 12, while .the flattened intermediate portion is designated 14. The plies or layers of the band are secured together, as by stitching 16, to integrate the loop. Each of the eyes includes two plies of the

band

18 and 20.

l have found that a highly suitable material for the yband is webbing made of nylon fibre, such as No. 10 nylon webbing. Obviously the webbing may be of a different grade number and be of various Widths and thicknesses to suit the particular application of the sling. The webbing may also be formed of Dacron, Orlon, or some other synthetic fibrous material.

While I have described the sling as being formed of nylon webbing, it is to be understood that cotton, and other fibrous materials may be used. Also it is within the purview of the invent-ion to use solid bands 0f nylon, or tapes, such as pressure-sensitive tapes. Any band-like material may be used, if the plies will lock themselves together as hereinafter described.

When .thesling is formed .of nylon webbing and constructed as shown in Fig. l and certain other of the figures, the webbing locks itself together, particularly in the eyes 10 and 12, so that the stitching 16 may be en,- tirely eliminated and still the sling will support as much weight as with the stitching. This results from the peculiar nature of the construction of the sling. `It will be observed that -thefree ends 221 and 24 of the webbing are located at the terminus of inner ply 18 of each eye; the end of the webbing terminating with portions which extend around the inside of each eye. When force is applied within the eyes tending to stretch the sling, the inner ply 18 tends to grip and lock against the outer ply 20 in the area of the eyes and this locking prevents slippage or movement of the plies relative to each other.

Normally, if one were to take a length of webbing and fold it longitudinally upon itself, one end of the webbing would terminate at the outer surface of the loop, such as is shown in Fig. 3 where the end 30* terminates at the outside. Applicant has discovered that if the portion of the webbing near the free end which would normally lie exteriorly of the loop is turned through a one-half turn over an adjacent ply of webbing, and such portion carried around the inside of one of the eyes with the end tucked between juxtaposed plies, the plies of the sling will tend to lock themselves as aforesaid. This locking arises as a result of the outer ply of webbing frictionally binding against the inner pliesand holding the sling intact when tension is applied. This frictional locking will increase as the tension load on the sling increases. This locking action will occur whether the sling is used as a choker, wherein one end of the sling is passed through the eye at the opposite end and the eye at the first end khooked to the hoisting device, or when used asa basket sling or a straight pull hitch. As a result of theplies of webbing locking themselves together when tension is applied to the sling, the construction permits full realization of the tensile strength of the webbing because the stitching is not relied upon to carry the load. InY Fig. 1 the webbing is shown at 26 being carried througha onehalf turn over ply 20. At the point of the turn ply Z1 becomes ply 18A and extends around the inside of eye 10 and terminates at end 22 which, it will be noted, is tucked between juxtaposed

plies

18 and 20 at the neck of eye 10.,

In addition to locking the plies of the sling together, when the sling is placed under tension, so that they will not slip relative to each other, thereby undoing the sling, the half turn 26 permits the concealment or tucking of the free ends of the webbing between adjacent plies of the sling to prevent the free end 22, which normally would terminate exteriorly of the sling, from being accidentally caught upon the floor or upon the goods lifted by the sling, tending to peel the outer ply oif of the sling. If the goods to be raised are resting on the floor, the sling must be pulled beneath the goods and while being so pulled, if the free end 22 is exposed to the goods or to the floor, there is danger of its peeling. Also, if goods have been placed on the floor by the sling and one then attempts to draw the sling from between the goods and the oor, unless free end 22 is concealed as shown in Fig. 1, there is a tendency for it to be peeled from the sling.

A sling constructed according to Fig. 1, and made of 1%" width, `1/s" thick nylon webbing, placed under a straight pulling tension, withstood 13,150 pounds before any sign of failure. Such failure was a breaking of some of the stitching which is used -to integrate the plies of the sling. Upon continuing the stretching tension, the sling withstood 17,800 pounds before the webbing broke. The sling shown in Fig. 1 but without the stitching 16 or 2S withstood 19,200 pounds before the webbing broke.

In Fig. 1 the half turn 26 is shown as being disposed within the length of the intermediate portion 14 of the loop and the free ends of the webbing terminating at the necks of the eyes and 12: within the intermediate portion of the sling. In Fig. 2 the half turn indicated at 26a is disposed within one of the eyes, namely, eye 10a, and the free ends of the

webbing

22a and 24a terminate substantially midway between opposite ends of the intermediate portion 14a. The plies of the sling shown in Fig. 2 will tend to lock themselves together when the sling is placed under tension in the same fashion as will the sling of Fig. l. It will be observed that the intermediate portion 14a of the sling of Fig. 2 of a 4-ply construction except for the interval between the spaced ends 22a and 24a of the webbing.

In both Figs. 1 and 2 the stitching 16 serves to integrate the plies and extends longitudinally of the loop throughout the area of the eyes and the intermediate portion. Additional stitching is also provided in the form of boxes 28. In any event, the stitching is only relied upon for the purpose of integrating the loop between lifting operations and not for the purpose of carrying the load to which the sling is subjected. Y

The construction shown in Fig. 3 differs from that of Figs. l and 2 in that the free end 30 terminates exteriorly of the loop and the stitching 16h and 2gb are relied upon to carry a portion of the Weight supported by the sling. Only the inner ply 18b will tend to lock within eye 12b. However, with sucient overlap of that portion of the webbing terminating at -30 within the length of the intermediate portion, the stitching 16b and 28h serves to impart suiicient strength so that the sling willwithstand considerable forces of tension. The free end 30 is, however, subject to being peeled from the loop.

A sling constructed according to Fig. 3 and made of l1%f widthand 1A Ythick nylon webbing No.l 10 withstood 13,600 pounds of stretching tension before the stitching broke, and upon breakage of the stitching the sling immediately pulled apart.

In Fig. 4 the character of the turn 26 shown in Fig. 1 is more completely illustrated. It will be observed that turn 26 is simply a half-turn carried over an adjacent ply of webbing. The box stitching 2S tends to integrate the turn with the plies.

In Fig. 6 I have shown another modification of th'e sling. This form of sling may be referred to as an endless sling. Both ends of the webbing are concealed or hidden between adjacent plies of the loop as shown at 32 and 34. The sling is stitched longitudinally in the same fashion as mentioned in connection with Fig. 1. However, the intermediate portion of the loop is not flattened together as is the case with Fig. l.

The Fig. 6 sling is a three-ply sling and includes the

plies

31, 35, and 36. Where the opposite ends 32 and 34 of the sling are overlapped, there is a thickness of four plies. Both the

ends

32 and 34 are concealed between juxtaposed plies of the sling and the turn 26h carries the outer ply across the adjacent plies to the inside of the sling with the end 32 being carried underneath such turn and concealed as shown. The inner ply 36 at opposite ends of the loop tends to lock itself against the intermediate ply 35 so that the sling is self-locking as with the slings shown in Figs. l and 2. The stitching serves only to integrate the loop and does not contribute to its strength. That the stitching does not contribute to the strength of the sling is borne out that upon subjecting the sling as constructed as shown in Fig. 6 and made of 1% x Ms No. 10 nylon webbing, the webbing broke at 27,400 pounds when the plies of the sling were stitched together as shown in Fig. 6, while without stitching the webbing did not fail until the tension had reached 33,000 pounds.

One of the advantages of the Fig. 6 sling over those heretofore described is that with three plies of webbing, one ply, viz: the intermediate ply, is always protected and therefore, even though either the inner or the outer ply may be cut accidentally,Y there will still be two plies capable of supporting the load. It will be noted that the Fig. 6 sling might be flattened throughout its intermediate portion as with the Fig. 1 sling with the intermediate portion stitched together, and that if this is done it is somewhat similar tothe Fig. l sling with another ply of webbing.

Fig. 7 is another modification of the sling. Here opposite free ends 3S and 40 terminate between juxtaposed plies and are at the end of portions of the webbing which extend around the inside of the eyes 10c and 12C. It will be observed Vthat the inner ply of either eye extends around the outside of the other eye, and vice versa. In this respect this form of the invention distinguishes primarily-from the other forms.

In Fig. 8 another form of the invention is disclosed. In this form the sling is made up of a plurality of separate lengths of band material, specifically two pieces. The first length has one end 42 which extends around eye 44, throughout the length of the sling and is folded through a half turn at 46 inside of eye 48 to terminate at 50. The other band has an end 52 which extends around eye 48 and over which the rst band is turned at 46, the second band thenV extending the length of the sling and folded inside eye 44 over the iirst band through a half turn 54 Ito terminate inside the sling at 56. As

with the Fig. 7 and the other embodiments, the plies may be secured together as by longitudinal stitching 57, and box stitch-ing 58. The ply constituting the first band is shown at 60 while the ply constituting the second band at 62.

A sling constructed as shown in Figs. 8 and 9 of 1%" x s No. 10 nylon webbing was subjected to tests and failure occurred at 13,200 pounds of tension. The sling of this figure is used for only light loads, and because fabricated of two pieces of webbing, has utility in using up spare pieces of webbing of varying lengths.

In each embodiment the stitching used should be of a material having the same stretching characteristcis as the material from which the bands are formed. For example, if nylon webbing is used as the band material, nylon thread should be used for the stitching. This will prevent the stitching from breaking as the sling stretches under tension.

Because the slings herein disclosed are made of webbing and thereby expose a fairly -wide area of surface contact with the goods to be hoisted, or the oor, as cornpared with the more nearly line contact of a rope or cable, the life of the slings is materially longer. Also, because of the relatively -wider area of contact between the slings herein disclosed and rope or cable slings, and the use of nylon in weaving the webbing, the slings will not mar or deface the goods.

When the Fig. 1 sling is used to lift objects by connecting the eyes and 12 to the hoisting device and the intermediate portion 14 is passed around and beneath the objects, the outer ply 20 serves to protect the inner plies of the intermediate portion of the sling. Such outer ply may be substantially cut through and yet the sling will be very nearly as strong as it was initially because of the reliance upon the inner plies to carry the load.

I claim:

1. A sling comprising: an elongate band doubled longitudinally upon itself in oppositely extending overlapping end relation to form a closed loop, that free end portion of the band normally terminating on the outside of the loop being folded over an adjacent portion of the loop and terminating within the loop, and means securing opposite sides of said loop together in juxtaposed relation intermediate opposite ends to provide separate eyes one at each end.

2. A sling comprising: an elongate band doubled longitudinally upon itself in oppositely extending overlapping end relation to form a closed loop, said loop being flattened throughout an intermediate portion of its length to juxtapose opposite sides thereof and provide an eye at each end of the attened intermediate portion, that free end portion of the band normally terminating on the outside of the loop being folded over an adjacent portion of the loop and extending around the inside of one of the eyes and terminating interiorly of the loop, and means securing juxtaposed portions of the band together in said intermediate portion to integrate the loop.

3. A sling comprising: -an elongated band folded longitudinally upon itself in oppositely extending overlapping end relation to form a closed loop, said loop being iiattened together throughout an intermediate portion of its length to provide eyes at opposite ends of the attened portion, that end portion of the band normally terminating on the outside of the loop being folded over an adjacent overlapped portion and extending around the inside of one of the eyes and terminating at said attened intermediate portion, the other end portion of the band extending around the inside of the other eye of the loop terminating at said attened intermediate portion, and means securing said flattened intermediate portion of the loop together to integrate the loop.

4. A sling comprising: .a band folded upon itself to provide a closed multiply loop, said loop being attened together throughout an intermediate portion to provide separate eyes one at each end of the intermediate portion, that portion of the band adjacent the free end which would normally terminate exteriorly of the loop being folded through a turn over an adjacent ply and tucked between juxtaposed plies to protect such free end, and means securing juxtaposed plies and said tucked end to gether to integrate the loop.

5. The invention as defined in claim 4 characterized in that said free end is tucked between juxtaposed plies of the band in said intermediate portion.

6. The invention as defined in claim 4 characterized in that the opposite end of the band from that turned across an adjacent ply of the band terminates between juxtaposed plies in said intermediate portion.

7. The invention as defined in claim 4 characterized in that said turn is disposed within one of the eyes at one end of said intermediate portion and each end of the band is concealed between juxtaposed plies within said intermediate portion.

8. The invention as defined in claim 4 characterized in that said turn is a half turn and carries that ply of the band on the outside of the loop across the adjacent ply to the inside of the loop and the free end is tucked between juxtaposed plies within said intermediate portion.

9. A sling comprising: a length of webbing folded longitudinally upon itself to provide a multiply loop, said loop being flattened throughout a portion of its length to provide a multiply eye at each end of the intermedi-ate portion, and that portionl of the webbing which would otherwise terminate outside the loop being turned over an adjacent ply and extending around the inside of one of the eyes and terminating inside of the loop, and means securing together adjacent plies throughout said intermediate portion to integrate the loop.

10. The invention as defined in claim 9 characterized in that the opposite end of the webbing terminates at the end of a portion of the webbing extending around the inside of the other eye of the loop with the end tucked between juxtaposed plies of webbing.

ll. A sling comprising: a band folded upon itself in oppositely extending overlapping end relation to provide a closed multiply loop, an outer ply of the loop normally terminating on the outside of the loop being folded through a half turn over an adjacent inner ply to terminate interiorly of the loop, and means securing the piles together to integrate the loop.

12. The invention as defined in claim 11 characterized in that said folded ply extends completely around the inner periphery of the loop.

13. The invention as defined in claim l2 characterized in that the end of said folded ply which extends cornpletely around the inner periphery of the loop is tucked through said turn to dispose the end between juxtaposed plies.

References Cited in the tile of this patent UNITED STATES PATENTS Re. 22,509 Brandon July 4, 1944 2,771,315 Fenwick Nov. 20, 1956 2,813,745 Frieder et al. Nov. 19, 1957