US2979982A - Buoyant cordage - Google Patents

Description

April 18, 1961 E. w. WEITZEL' 2,979,982

BUOYANT CORDAGE Filed Feb. 29. 1956 EDWARD W 14 5/7254 BY ait-nfidLw-kldigm ATTORNEYS INVENTOR. I

BUOYANT CORDAGE Edward w. Weitzel, Hickory NC. assignor to Shuford lglillsi Inc., Hickory, N.C:, a cbrporation of ;North aro ma Filed Feb. 29, 1956, Ser. No. 568,490 6 Claims. .(Cl. 87-.6)

This invention relates to cordage products such as ropes or lines and, more particularly,-to a corda-ge product particularly constructed to be used in connection withaquatic sports, such as water skiing and yachting, and in connection with safety devices, such as lifesavinglines and the like.

It is a primary object of this invention to provide a buoyant cordage producthaving a specific-gravity of less than one to permit the same to float on water for an indefinite period of time.

It is also an object of this invention to providea buoyant cordage product which has a high degree of' flexibility which readily permits the same to'be' easily handled a'nd manipulated as, for'example, to tie knots in the same.

It is a further object of this-invention to provide'a cordage product having a high resistance to abrasiomby forming the outer cover of the product-from nylonf-which greatly prolongs the life of theproduct.

It is a more specific object of this invention to 'provide a cordage product having a specific gravity of less than one and wherein the product comprises a braided. nylon covering and a flexible polyethylene jcore surrounded by said covering, said core being so formed'as toentrap air pockets therein to add to the buoyancy of the product and the nylon covering providing a high degree of resistance to abrasion.

Some of the objects of the invention having been stated, other objects will appear as the description proceeds when United States Patent taken in connection with the accompanying drawings, in

which Figure 1 is an enlarged side elevational view of the first form of the cordage product, with part of the covering removed and the core cut on a bias for the purpose of clarity;

Figure 2 is a greatly enlarged trans-verse sectional view taken on line 2-2 of Figure 1 and showing the manner in which the sheet material forming the core is folded to provide or entrap a plurality of air pockets therein;

Figure 3 is a view similar to Figure 1 showing the second form of the invention wherein the core is formed of a foam polyethylene rod;

Figure 4 is a view similar to Figure 1 showing the third form of the invention wherein the core comprises a tubular film material folded to entrap pockets of air therein.

Referring more specifically to the drawings, particularly Figures 1 and 2, wherein the first form of the invention is shown, reference numeral 10 broadly indicates the covering or wrapping of the cordage product and is shown as being in the form of a tubular braided construction formed from a plurality of strands 11, preferably nylon, which has a water absorbency of only about 6% when immersed, or other suitable material having high strength, good resistance to abrasion and low water absorbency. A core broadly indicated at 12 is surrounded by the covering or wrapping 10 and comprises a flat sheet or film 13 of polyethylene material which has been folded upon itself to provide a plurality of longitudinally extending product.

2,979,982 Patented Apr. 18, 1961 :pas'sageways ior'airi pockets 14, as clearly shown in Figure 2, which entrap air to add to the buoyancy of the It will be observed in Figures 1 and 2 that the opposite ends 13a, 13b of the film or sheet material 13 have been *turnediinwardly to increase the sealing effect of the core 12 to prevent the escapementof the air from the pockets 14.

The sheet material 13 is formed of polyethylene which has 'a water absorbency of less than .01% and which has aspecific gravity of .92 as compared to 1.14 for nylon and, therefore, will float on water indefinitely. The construction-of the cordage product is such that the combined specific gravity of the nylon braided covering 10 and the polyethylene sheet 13 is equal to less than one to present a cordage product that is inherently buoyant. This construction is accomplished by the core 12 having a diameter greater than half the diameter of the product,'thus permitting the lower specific gravity of the core to olfset the higher specific gravity of the covering. The air entrapped by the-sheet material 13 in the pockets 14 greatly'increasesthe buoyancy of the product and thus presents acordagesproduct that will float indefinitely on water.

An example of a constructionof'a product formed in accordance with the first invention comprises a core formed-of a six (6) inch wide sheet of polyethylene film havinga thickness-of 1 /2 mil or .0015 of an inch which is folded upon itself an innumerable number of times. The coreis surrounded by a braided jacket formed from 16 ends of 840 denier nylon to present a finished product having an overall diameter of .183 inch.

'No'w,'refer'ring'more specifically to Figure 3 wherein the-second form of the invention is illustrated, reference numeral 201 broadly indicates a covering or wrapping formed-in a similar manner as the wrapping in Figure 1 from aplur-ality of nylon cords21 braided together. .The

c'overing20 surrounds a rod-like c0re'22 formed. of foam I float on water for an indefinite period of time.

Now, referring to Figure 4 wherein the third form of the invention is illustrated, reference numeral 30 broadly indicates a covering or wrapping formed of a plurality of braided nylon strands 31 encircling a core formed of a tubular polyethylene sheet 32 which upon being collapsed and folded has a similar appearance in cross section as the polyethylene sheet shown in Figure 2.

The provision of the tubular polyethylene core material 32 instead of the flat sheet material 13 of Figure 1 presents a core material which entraps a greater number of air pockets and yet presents a cordage product having all the desired characteristics of flexibility and resistance to abrasion as the first form of the invention.

The outer end portions of all forms of the finished product may be sealed by applying heat thereto which causes a melting or flowing of the thermoplastic polyethylene and nylon to seal the exposed edges of the materials together. This sealing further entraps air in products shown in Figures 1, 2 and 4 by preventing the escapement of the same from between the folds of the core material and from the inner confines of the enclosed tube of Figure 4.

Accordingly, there have been disclosed three forms of the invention wherein each form is provided with a nylon built-in buoyancy by the provision of a plurality of air pockets therein.

In the drawings and specification there has been set forth a preferred embodiment of the invention and several modified forms thereof and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being defined in the claims.

I claim:

1. A highly flexible and buoyant cordage product com prising a jacket formed of a low water absorbent textile material and a core formed of a loW water absorbent material having a specific gravity of less than one surrounded by said jacket, said core having a plurality of randomly spaced air pockets entrapped therein, and all of said randomly spaced entrapped air pockets being formed by said core forming material having a specific gravity of less than one.

2. A highly flexible and buoyant cordage product comprising a jacket formed of a low Water absorbent textile material and a core formed of polyethylene material surrounded by said jacket, said core having a plurality of randomly spaced air pockets entrapped therein, all of said entrapped randomly spaced air pockets being formed by said polyethylene material, the proportion of the amount of textile material forming said jacket to the amount of polyethylene forming said core being such that the specific gravity of the combined materials is less than one.

3. A highly flexible and buoyant cordage product comprising a braided tubular covering formed of a low water absorbent textile material and a core formed of a low water absorbent sheet material having a specific gravity of less than one positioned in said tubular covering, said sheet material being folded upon itself to form a plurality of randomly spaced, enclosed air pockets within said core.

4. A highly flexible and buoyant cordage product comprising a braided tubular covering formed of a low water absorbent textile material and a core formed of a low water absorbent sheet material having a specific gravity of less than one positioned in said tubular covering, said sheet material being folded upon itself to form a plurality of randomly spaced, substantially parallel, enclosed air pockets within said core, the proportion of the amount of textile material forming said covering to the amount of sheet material forming said core being such that the specific gravity of the combination of materials is less than one.

7 5. A highly flexible and buoyant cordage product comprising a jacket formed of a low Water absorbent textile material and a foam polyethylene core surrounded by said jacket, said core having a plurality of randomly spaced air pockets entrapped therein, and all of said entrapped randomly spaced air pockets being formed by said foam polyethylene.

6. A highly flexible and buoyant cordage product comprising a jacket formed of a low Water absorbent textile material, and a core formed from a tubular film of polyethylene and positioned in said jacket, said tubular film being folded upon itself to form a plurality of randomly spaced, enclosed air pockets within said core, and all of said enclosed randomly spaced air pockets being formed by said folded polyethylene.

References Cited in the file of this patent UNITED STATES PATENTS 2,107,467 Buhler Feb. 8, 1938 2,231,869 Andrews Feb. 18, 1941 2,325,060 Ingersoll July 27, 1943 2,577,077 Forsberg Dec. 4, 1951 2,614,451 Lippey Oct. 21, 1952 2,737,075 Poitier et al Mar. 6, 1956 2,748,525 Volz June 5, 1956 2,759,990 Bean Aug. 21, 1956 2,862,282 Beebe-" Dec. 2, 1958 FOREIGN PATENTS 12,441 Germany Dec. 8, 1955 18,536 Netherlands Aug. 15, 1928

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