US1475859A

US1475859A - Plaited cable sling

Info

Publication number: US1475859A
Application number: US585824A
Authority: US
Inventors: Nyman Charles
Original assignee: Individual
Current assignee: Individual
Priority date: 1922-09-01
Filing date: 1922-09-01
Publication date: 1923-11-27
Anticipated expiration: 1940-11-27

Description

Nv. 27 1923A JL (Il C. NYMAN LAITED CABLE sLING Filled sept. 1. 1922 3 Sheets-Sheet 1 Nov. 27,1923 l1,475,859

C. NYMAN PLAITED CABLE SLING Filed Sept. l, 1922 3 Sheets-Sheet 2 Nov. 27 1923 gal-'2.

1,475,859 c. NYMAN PLAITED CABLE SLING 3 Sheets-Sheet 5 Filed Sept. l 1922 Patented Nov. 27 1923.

lUNITI-:D STATES- CHARLES NYMAN, or rrr'rs BURGH, PENNSYLVAA, AssIGNon or ONE-RALF 'ro DONALD MURRAY, OF WILKINSBURG, PENNSYLVANIA.

PLAITED CABLE sLING.

Application led September 1, 1922. Serial `No. 585,824.

To all whom t may concern:

Be it known that I, CHARLES NYMAN, a citizen of the United States, residing lat Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Plaited Cable Slings, of which the following is a full, clear, and exact description.

This invention relates to slings, such as W are used, for example, in handling struc- .turallsteel by cranes.

ln handling structural steel members,

bundles of pipe and articles of a similar nature, slings are commonl employed.

These slings comprisea cable-hke body portion of sufficient length and tensile strength to accommodate the load and have at each end an eye for engaging the crane hook.

In use, the sling is placed around. the article to be raised 'and the eyes are put over the crane hook. Sometimes shackles are carried by one or both eyes.

Slings are 'generally made in a number of sizes for handling different weights of material, since they must be as flexible as possible to facilitate theiruse. The slings are 'in-.constant use around manufacturing plants and on buildings in process of erection, and suffer considerable wear and abuse. They are frequently subjected to excessive strains, since a light sling will generally be .used in reference to a heavier one on account of its greater flexibility.

Slings -of chain have been found dangerous in use because of the liabilityof alink to suddenly break.

Ordinary slings -made lof twisted cable have been found objectionable in use on account of their tendency to twist upon themselves.f If a sling made of twisted cable is stretched by a ,heavy load and allowed to hang doubled, as is the case when it hangs idle with Iboth eyes over the crane hook, 1t will twist upon itselflinstead of hanging free and open as is desired.'

rTwisted slings have also been found objectionable because when they wear, the

small strands of wire of which they arecomposed are likely to break and untwist.

This results in a rough sling that is likely to cut or tear the hands of the workmen when it is being used.

- My invention provides a sling vthat is plait/ed instead of being twisted and is therefore free from any tendency to twist upon itself. Moreover, if a wire strand parts, it can only unravel a very short distance before a crossing strand prevents fur- -ther loosening.

By using a plaited construction I am enabled to utilize a core or body, such as a hemp cable, of considerable diameter. This core forms a pad for the strands and minimizes cutting and chafing. It alsol gives more body manipulate.

The forming of eyes in the ends of the sling is generally accomplished by splicing. rFliese splices are hard to make, are not always dependable, and make bulky and unsightly ends on the sling. I have found it possible to plait an entire sling from a single strand, which may be of small cable. It is thereforenecessary to splice only the two ends of this elementary strand, the eyes being formed from loops left at the ends of the sling during the plaiting. ln this way, the objectionab e splices are eleminated.

In the accompanying drawings, illustrating the preferred embodiment of this invention:

Figures yluto 7 illustrate diagrammat- Ilflsally my preferredwmanner of making a s 1n f Fgiggure" 8 is a diagrammatic view of the plait used in making a sling;

Figure 9 is aview, partly broken away, showing the manner of fo-rmingan eye in the end of the sling;

Figure 10 shows the finished eye;

Ffiguie l1 is a view of a sling made according'to my invention; i

to the sling, making it'easier to Figures 12. to 16 illustrate diagrammatically, the manner of making a sling according to my invention when no" rope core is used; and v Figure l? is a view of a partially plaited sling when plaited as shown in Figures 12 to 16. l

In the preferred form of my invention, a

single elementary strand of suitable length has its ends ,spliced together to form an endless strand which is formed into an even number of loops as shown in Figure 1. This elementary strand may, if desired, be formed of vtwo or more pieces spliced at their ends into an endless strand. `For purposes of illustration, a sling formed from There may bc any even number ot loops, and the strength ot' its sling may be varled shown in Figure 3.

either by using more loops or a larger size cable. 'l he loops are termed a little longer than the finished sling, since they are shortf cned somewhat by the plaiting.

yThe {ieXible elementary strand trom which the loops are formed may be a single Wireor cord, but is preferably a small cable, since this gives greater flexibility. The two ends of the strand. are spliced togethenleaving six loops at each end. The splice is not necessarily at a lobp, as shown in Figure 1 by dotted lilies, but may be made any- Where in the doubled strands it it is desired to keep the splice away trom the eye of the sling.

After the doubled strands are formed, the loops at one end are gathered tege-ther over a. thimble 7 and the strands are evenly spaced around a core 8, which may be a hemp cable terminatingadjacent the thiinble 7. A seizing wire 9 temporarily holds the strands in their proper relationship, as

In my preferred-method of plaiting, alternate strands are Worked `in opposite directions, as shown diagrammatically in Figure 8, alternately passing' over and under the strands they` cross.

Figures 4 to 7 Lshow the sling in sect-ion at various points during the plait. 1n Figure 4,

strands

2, 4 and 6 are shown as having been rotated clockwise from their position in Figure 3, passing under strands 3*,

5 and 1, respectively. ln the next ste-p of the plait, shown in Figurer,

strands

1, 3 and 5 are shown as having been rotated counter-clockwise under strands 4. 6 and 2, respectively. Figure 6 shows their relative positions after

strands

2, 4 and 6 have been lifted above

strands

1, 3 and 5 by the maker.

As shown in Figure 7, the even numbered strands, 2, 4 and 6 are again rotated clockwise, this time under

strands

1, 3 and 5, re-` spectively. The steps of rotating odd numbered strands counter-clockwise and even numbered strands clockwise, are alternated through the length vof the sling. This gives in ettect a plait such as shown in developed diagrammatitl form in Figure 8, With siX loops at each end.

lt will be evident that it' desired the seizing wire) may be placed around the double strands at their middle points, and the plaiting carried on in both directions to the end. ln case a shackle link is to be carried by onc eye of the sling, the elementary strand, is threaded the requisite number ot times through the shackle link to form the double loops before its ends are spliced` together, and then the sling is plaited 'from end to end. ln case no shackle is employed, the plaiting may be started at Ithe middle of the sling and pro-gress toward each end, the loops at the ends of the double strands being then served with eyes When the ends of the sling are reached.

' v It will be understood that my invention is not limited to the use of a single elementary strand.

Figure 12 illustrates two strands as they may be placed to form a sling. Here, the two elementary strands are doubled, as shown, to form four

single strands

13, 14, 15 and 16. As mentioned above. the plaiting may start from the middle if desired. In this case, the seizing Wire 9 is placed about the position they occupy when fastened by the seizing Wire 9. lln Figure 14,

strands

14 and 16 are shown as having been rotated clockwise from `their position in Figure 13, passing under strands 15 and'13, respectively. Figure 15 shows

strands

13 and 15 as having been rotated counter-clockwise under the

strands

14 and 16, respectively.

rThe strands

14 and 16 are then rotated clockwise from` their position in Figure 15, passing under

strands

15 and 13, respec tively. It will be apparent that this operation of rotating the even numbered strands clockwise and the odd numbered strands counter-clockwise, is the same as sho\vn in the embodiment of Figures 1 to 11, 1n-

clusive, even tho-ugh no rope core has been used.

It Will be apparent that in order to make the plait shown vin Figures 12 to 17. the ends of the elementary strand cannot be spliced until the plaitI has been completed. Figure 17 sho-Ws strands 13 and l5 as having been joined in a splice 17 to' torm a loop. This loop along `with the

loop ot strands

14 and 16, is served with Wire as betere, to torm an eye in the end of the sling.

, lt will be apparent that the splicing of the so much for the convenience of making the

strands

13 and 15 at one end of the sling, and corresponding splicing of strands 14 and 16Y at the other end of the slin vmakes in efect; a sling comprising two en less elementaryj/ strands. The importance of forming a sling from one or more elementary strands is not sling as in the strength and appearance of the finished sling, the .only splices being in the elementary strands instead of in the body of the sling proper, as is the case with the twisted cable sling. It will be apparent that the entire strain of a sling under load is not carried by the splice.

The cable sling has all the strength of wire'rope, and will not suddenly break like a chain; Individual'wires will break and give Warning of overload or weakening of the sling. The plaited Asling is more flexible and has not the tendency to twist of a twisted wire cable. There are no splices ofthe plaited cable as a whole, so that weakened or bulgy places are obviated. T he only splice or splices are formed in the endless elementary strand from which 4the cable 'is v.plaited lf such elementary strand is spliced at more than a singleA place, the splicesmay be arranged so as not to come at the same place in the completed cable. l While l have described one embodiment of my invention, it will be understood that this does not illustrate thel limits of my invention, as changes may be made in the sling or inthe manner of making it within the scope of the following claims.

l claim: 'Y v l. A plaited cable sling including an` endless elementary strand plaitediso as to form a sling, substantially as described.

2. A plaited cable sling comprising an endless elementary strand formed into double strands, and a flexible core, the double strands being plaited over the iiexible core to form a sling, substantially as described.

3. A plaited cable sling comprising a cable-like bodygportion and eyes at the ends thereof, the body portion being plaited from an endless elementary strand, substantially as described.

4.. A plaited cable sling having an eye at one end, the strands extending from the body of the sling around the eyeand back to form the body, the number' of strands immediate'ly beyond the eye being substantially the sameas at a point in the body remote from the' eye, substantially as described.

5. A cable sling having an eye at one end .formed of a plurality of plaited strands extending in a continuous manner back and forth through the body and around the eye, substantially as described. y

6. A cable sling having al body and an eye at one end, said bodyfbeing formed of two ply plaitedy strands, the eye being formed of loops connecting the plies of the strands to each other, substantially as described. A

7. A'cable sling having a lbody and an eye 'at each end, said body being formed of plaited two ply strands, the plies of each strand being connected to each other at one end of the body by open loops which form the eyes, substantially as described. v

8. A cablesling having a body and an eye at each end, said body being formed of plaited two ply strands, theplies of each strandbeing connected to each other at oneA end of the body by open loops which form the eyes, said strands being formed of a single endless element, substantially as described.

9. A sling having an -eye at eachl end of its body, formed of two sets of strands, each set 'being formed of an equal number of pairs of strands, the one set extending in a helical manner about an axis in a clockwise direction, while the other set extends around said axis in av counter-clockwise 'direction to form the body of the sling, alternate pairs of 'one set overlying and underlyingr alternate pairs oi the other set. while 4the other pairs of tlie rst set underlie and overlie the other pairs of the second set, the eyes at the ends of the body being formed of loops con-v necting the strands `to each other, substantially as described.

A 10. A sling having an eye at each end of its body, formed of two sets of strands, each set being formed of an equal number of pairs of strands, the one set extending in a helical manner about an axis in a clockwise direction, while the other set extends around said axis in a counter-clockwise direction to form the body of the sling, alternate pairs of one set overlying and underlying.alter nate pairs of the other set, while the other pairs of the iirst set underlie and overlie the other pairs of the Second set, the eyes at the ends of the body being formed of loops connecting the strands to each other, and a iex- L ible core within the body about which the two sets of strands are wound, substantially as described.

11. A sling having a bod and an eye at each end formed of pairs o plaited strands having cohnecting loops at their ends,.the body being formed by the plaited portions of the strands, while the eyes are formed of the loops, substantially as described.

12. A'sling having a body portion with an eye at -each end formed of a plurality of plaited strands and strand connecting loops, the strands and loops being continuous and endless, substantially as described.

13. The method of making a sling with an eye at one end, the steps of* doubling izo strands to form a loop at one end of two strands', arranging said strands in two sets,

. forming an eye at the other end of the sling bythe loops connecting the strands of each pair, substantially as described.

15,i The method of making a plaited cable sling with eyes at its ends, including the forming of a plurality of double strands and plaiting them into a cable sling, and forming the eyes of loops connecting the'strands to each other, substantially as described.

16. The method of making a plaited sling, including doubling an elementary strand to form a plurality of double strands With loop ends, and plaiting said double strands into a cable sling, and leaving the loop ends open at both ends to form eyes, substantially as described.

17. The method of making a plaited cable sling, including the forming of an endless elementarystrand, doubling the elementary strand to form a plurality of double strands, and plaiting said double strands into a cable sling, substantially as described. i

18. The method of making a plaited cable sling, including splicing the ends of a single strand to form an endless elementary strand, doubling the elementary strand to form a' plurality of double strands, and plaiting said double strands into a cable sling, substantially as described. y

19. The method of making a plaited cable sling, including forming an endless elemening said double strands into a cable sling, and forming loops at the ends of the double strands into eyes at the ends of the sling, substantially asv described.

20. The method of making a plaited cable sling, including the vforming of an endless elementary strand, doubling the elementary strand to form a plurality of double strands, and plaiting said double strands over a flexible core and into a cable sling, substantially as described.

21. The method of making plaited cable slings, including the forming of an endless elementary strand, doubling the elementary strand to form an even number of double strands, rotating alternate double strands in opposite directions around the axis of the sling` and alternately passing the rotated double strands over and under the crossing strands to form a plaited cable, and forming the loops at the ends of the double strands into eyes at the ends of the sling, substantially as described.

22. The method of making a plaited cable sling, including the Jforming of an endless elementary strand, doubling the elementary strand to form an even number of double strands, rotating alternate double strands in opposite directions around a flexible core, alternately passing the rotated double strands over and under the crossing strands to form a plaited cable, and forming the loops at the ends of the double strands into eyes at the ends of the sling, substantially as described. f In testimony whereof I have hereunto set my hand. y

CHARLES NYMAN.

'tary strand, doubling the elementary strand to form a plurality of double strands, plait-y