US1479865A - Rope structure - Google Patents

Description

im, 8, @924o H. G. METCALF ROPE STRUCTURE Filed June` 18, 1923 Patented dan.; S, i924,

naires? santasN Ld'lt FATN? @FFQM Hannan e. Maronti?, or AUBURN, nnw Yoan.

RCPE STRICTURE.

Application filed June 18, 1923. Serial No,v 646,183.

v drawings, forming part of this specification.

This invention relates to improvements in cordage, particularly applicable to rope structures generally, that is to say, those structures made up of three, four, six, `or nine strands or readies assembled either in regular laid rope, or in cable-laidrope, the object of the invention being to increase the strength of the rope as well as the lasting qualities in the performance of work requiring constant bending or liexure, as well as in Work wherein the rope is subjected to abrasion.

In the production of rope embodying the present invention certain developments made in connection .with the arrangement of the fibers inthe rope structure are utilized with the object first of simplifying and reducing the cost of manufacture and, secondly, of not only increasing the strength of the rope, under tension, but also increasing its flexibility and internal wear resisting qualities.

In accordance with the present invention, the strands or readies from which'rthe rope structure is built up are each composedv of an internal portion wherein the -main strength .of the rope to resist tension strains is found, and an external portion designed 46 to resist wear and abrasion,'but, of course, to a certain extent also adding to the tensile strength o'f the rope. rll`he internal portion of each strand or ready is formed directly of sliver fibers and the fibers occupy substantially parallel relation to each other and are twisted only to a slight degree, usually conforming to the forming twist of the strand or ready, but the degree 50, of twist may be varied in accordance with known practice. Buried within the central sliver ber portion of the strand or ready and preferably axially thereof, there is a yarn or a ply yarn which yarn or ply yarn is lthoroughly covered and impreg. nated with graphite or grease or waterproofing material having water repellant and lubricating qualities. Around the central portion of the rope strand or ready so formed of sliver fiber, there 'is wound in parallelism a covering composed of yarns or ply yarns and there may be one or a plurality of layers vof such yarns or ply yarns to Agive the desired abrasive resisting qualities to the rope, as well as to exert a ,binding action on the central portion, in order to increase the strength of the rope by eliminating any tendencyof the `fibers to slip and separate from each otherwhen subjected to severe tensionstrains, especially where the twist imparted to the sliver center is not in itself suiii'cientto accomplish this result. In'some instances each of a series of slivers has incorporated in it a single yarn or a ply yarn which is thoroughly covered and impregnated with the lubricating and water .resisting material or the lubricating yarn'may be at the center v and surrounded by the series of slivers, but in all cases it is embedded in a relatively large mass of sliver fiber. l

In order that the use of the terms sliver,

"yarn, and ply yarn may be understood herein, such terms may be defined as follows: A sliver is a relatively large body of fibers which have been straightened and doubled the requisite number of times to insure uniformity and parallelism of they fibers, and this sliver fiber is in the rope structure, twisted-onlyisutficiently to hold the fibers together and to prevent them from separating readily by being pulled apart. In some instances this sliver may have its individual fibers held together' inA part or in whole by thepenclosing sheath of yarn or ply yarn. y A single yarn is a relatively small body of libers suitably doubled and straightened and twisted or spunv into a.. structure, which has the relatively hard 'i twisted characteristics of a thread' or cord. A ply yarn is a plurality of single yarns which are twisted together and maintain their form or the characteristics of a cord formed of a plurality of single threads or ,i 6,5 stretched or elongation of the ropatakes lin the drawings: Figure l represents a section of a three strand rope, one strand at the end being opened out to illustrate the internal structure;

Fig. 2 is a cross section of the rope illustrated in Fig. l; and

Fig. 3 is a cross section illustrating a modification wherein a plurality of slivers constitute the center portion of the rope and in each sliver there is embedded a lubricant impregnated single yarn or ply yarn.

Referring particularly to Figs. l and 2, the letter A indicates the .enveloping sheath for each of the strands or readies, this enveloping sheath being formed of a single or plural layers of yarns a. These yarns may be, as ordinarily, either 'single or ply yarns, but are preferably single yarns, inasmuch as it is desirable to have the fibers of the yarns twisted together only to that.. degree which is necessary to constitute a good wearing or abrasion resisting cover or sheath, and at the same time to leave the fibers as free as possible from all tendency to cut each other or to shear under the action of bending or tension stresses. The center portion of each strand or ready is formed of sliver ber, a sliver or series of sliverspreferably, though not necessarily, four or more in number, as indicated at B, and these slivers have a twist imparted to them, which, in the preferred structure, substantially corresponds to the twist imparted to the whole ready or strand in laying the sheath or cover thereon,

in the rope machine, to which machine the sliver is preferably fed in a substantially untwisted condition. Embedded in the sliver fiber center so formed is the impregnated yarn or ply yarn C which is illustrated in thev drawings as a black center, indicating that it is impregnated with graphite, grease or other lubricating and water-proong compound.

Insteadof incorporating the lubricating yarn or ply yarn B- in the center or along the axial line of each strand or ready, each of the slivers incorporated in the center may have an impregnated yarn E incorporated therein, as indicated -in Fig. 3 of the drawing, there being thus incorporated ineach ready a plurality-of impregnated yarns separated from each otherbyjthe fiber constituting the adjacent portions of the slivers from which the center is formed, thus distributing the lubricatingand waterLrepellant mal'terialthroughout a greater area of the fiber.l

The impregnated yarns so incorporated in the slivers are twisted to a greater degree than the slivers themselves, and consequently present a greater length Aof ber in a'given length of rope. .linother words, this yarn belng a hard Atwisted portion of the structure will .be capableof lengthening out when By locatingthe lubricating impregnated v' yarn in a vsurrounding body of soft fibers, so to speak, it is found that the distribution of the lubricant is not only such that it is most effective where lubrication is secured, but in use, the lubricant distributes itself to the surrounding fibers and after a brief interval of use the center of the rope has lubricating qualities imparted there-to 'to a greater or less degree throughout, and from the beginning the rope as a whole is flexible to a degree which is practically impossible of 'attainment in ropes heretofore produced and which were made of yarns in the ordinary way.

An additional advantage has become inanifest in ropes of this character, due to the fact that while the fibers constituting the rrope are eiectually clamped together, so to speak, as to prevent slipping with relation to eachother, their entire tensile strength becomes available without that tendency to shear and cut, as in all liard laid ropes heretofore madewith the result that the tensile strength of a rope made in-accordance Awith the present invention, aswell as its capacity for resistingbending stresses and constant usage in bending or external abrasion are greatly increased.

It will be understood, of course, that the 'this art.

-`Whatlclaim is: Y

1. A rope structure comprising a plurality ofstrands or readies laid together in twisted relation tovform the finished rope, each of said strands comprising a twisted yarn or ply yarn impregnated with a lubricating or water repellant substance and embedded in and surrounded by a relatively large body of sliver fibers twisted to a degree less than that of the impregnated yarn to form a relatively soft center, the whole being surrounded by yarns each twisted to a greater degree than the slivers, said yarns being spirally laid about the center and with adjacent yarns in contactwith each other to form an enveloping sheath.

2; A rope Structure comprising a plurality of strands or readies laid together in twisted relation to form theinished rope, each of said Strands comprising an envelope 4or lllilO lill@ las ' laid about a center with adjacent yarns' `1n contact, a relativel large sliver fiber 'center twisted to substantlally conform to the spiralA 5 lay of the envelopin yarns and a yarn or ly yarn of twisted bers impregnated with ubricantv embedded in the sliver center.

3. A rope structure comprising a plurality of strands or' readies laid together in twisted l0 relation'to form the finished rope, each of said strands comprising laid about vaA center with adjacent 4yarns 1n a plurality of slivers twisted to conform to the spiral lay of the enveloping yarns and a yarn or sly arn of twisted fibers impre nated wit v1u ricant'and located centra y between the slivers.

v an envelope or sheath of individually twisted yarns spirally HAROLD G. METCALF.

contact, 'a relatively large center formed of j l5

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