US1444076A - Alfred e - Google Patents

Description

Patented Feb. 6, 1923.

UNITED STATES PATENT OFFlQE' ALFRED E. JURY, 0F NEWARK, NEW JERSEY. ASSIGNOIL BY MESNE ASSIGNMENTS,

TO MORGAN & WRIGHT, 0F DETROIT, MICHIGAN, A GORPORATIUN OF MICHIGAN.

STRAIN-RESISTING ELEMENT FGR RUBBER ARTICLES.

In Drawing.

To all who r it may concern:

Be it known that I. ALFRED E. JURY, a citizen of the United States residing at Newark, county of Essex, State of New Jersey, have invented certain new and useful Improvements in Strainliesisting Elements for Rubber Articles. of which the following is a full, clear, and exact description.

This invention relates to threads or cords, generically termed strain-resisting-elements, for incorporation with rubber into articles that are completed by vulcanization, such, for instance, and particularly, pneumati ctire casings. The elements may be incorporated either individually or colleetively' in the form of cord, Woven, or weft less, fabric. The objects of the invention among others a peering later are to improve the structure 0 the strain-resistingelements over what has heretofore been employed and to reduce the cost of their manufacture.

My invention is'notjrestricted to any particular kind of fibre, but for the purpose of illustration it will lie-described in connection with threads cords, and the like made from cotton. In t e usual manufacture of cotton thread, cords, etc. the cotton from the bale is loosely opened out and subjected to a course of treatment directed to the removal of the shorter staple, leaf, and other; foreign matter,- and to the. placing of the fibres into substantially parallel directions and to finally drawing out the fibres thus arranged into a uniform strand termed roving. The rovin has a. very slight twist imparted to it in or er to make sure of its maintaining its uniformity and parallelism during the sub sequent recesses which it must be subjected to ,in or er to produce the final cord.

The roving having no appreciable twist, the fibres composing it are in such loose con tact there is iittle or no friction between them and consequently there is no appreciable tensile strength. In order to produce the required frictional contact and conse quent tensile strength the usual practice is to draw the roping, which is of comparw tively large cross-techno. out into a fine filament and to s in it into what is termed a single yarn. .A number of these varns are then twisted together to form a plied yarn and finally a number of the plied yarnsare twisted together to form the cord.

The forming of the single yarn reql. ed'

the libr Application tiled October 16. 1918. Serial No 258,429.

much time and expensive machinery and is in fact the most costly operation in the 11mm ufacture of cord. For instance in the man ufacture of cord fabric for forming the plies of pneumatic tires for motor vehicles the'single yarn is usually formed by drawing out the rovin about. ten times its length I and. simultaneous y giving this finely drawn together by the two subsequent processes of twistin tie single yarns. The fibres are thus se f-retained to ether with a degree of permaneiicy that We ll adapts the'eords for the general Wear and tear of service tending to loosen the fibres. This. however, involves the. necessity, after having carefully formed the roving of uniform cro$-section composing a relatively large number of parallcl fibres, of then taking the backward steps of drawing the roving out until it is reduced in cross-section to a mere thread composed of a comparatively few fibres, and then eombininga number (fifteen) of these yarns together until the cord is again enlarged in section to the desired size to give the required strength.

It will. therefore be seen that if the roving can be used as originally formed, that is to say without resorting to the backward steps of drawing out and'tnen plying up, a material saving will be attained ill time and expensive apparatus employed. Moreover the tightly spun yarn and the plying of the same together by twisting. so tightly holds together that the cord is not of the desired degree of pliahilitv to withstand the required flexing that is necessary for the many uses to 'Wllltii the cords are put and therefore the tightly held fibres are weakened by repeated hr-Ling and prematurely breath.

I have discovered that a cheaper and warp yarn.

Vi ithout intending to limit myself and by way of example, a satisfactory tire fabric may be made with cords or yarns from 4 rovings of between t and a of an inch thick twisted together 5 times to an inch. The number and size of the rovings and the amount they are twisted together may, of course, be varied within wide limits, the essential idea being the utilization of unspun and substantially untwisted fibrous rovings as the base of a strain resisting element for vulcanized rubber articles.

T he cord or warp yarns may be built into the rubber articles before curing as thus completed or they ma be woven into fabrics or otherwise rendere manipulatable for incorporation in rubber articles. They ma be utilized for both the warp: and we t threads of a plain woven fabric, or as the ivarp threads of what is known as cord fabric. The latter is largely used in the manufacture of tires and consists of close 1 ing warp threads held together by fine filing threads of say No. 20 at intervalsof of an inch. Phe weft threads of cord fabric for tires may be made as fine as desired and their spacing may be varied, the sole function of these filling threads being to hold the cords together during the subsequent mani ulation of the fabric. Obviously also, tie cords or warp yarns in close parallel relation may be united by intermediate webs of rubber connecting them and forming what is called weftlem fabric.

Whatever form the cord or warp yarn may be put into for incorporation in the rubber article, the next step is to bind its fibres together with one or more coats of rubber or a vulcanizablerubber composition. This may be done in any suitable manner as by the usual friction or skim coating methods. Without a binding material the fibres of the several unspun and loose rovings com- 'posing the strain resisting elements are easily disarranged when subjected to abrasion. While in their bare or uncoated condition the warp threads or varns are therefore commercially useless, it has been discovered that they function very satisfactorily as strain resisting elements when imbedded in rubber composition and vulcanlzed. The loose fibres of the rovings in each element seem to be held in their loose relation without liability of abrasion on (meanother and the elements possess the requisite tensile strength. At the same time they are more flexible and less liable to heat than previously used hard twisted cords or strain resisting elements.

It is obviously not essential that the binding material, relied upon to give permanency to the twists of the cord, be applied to the cords individually for in many cases such for instance as the manufacture o pneumatic tires, the cords may be woven into cord fabric or the usual fabric, or otherwise combined and the twisting of the strands together may be relied upon to impart sufficient permanency to the cord to permit of such and similar manipulation, so that after the cords have been formed into a fabric or otherwise formed into a layer or ply they'may be treated with the binding rubber in any of the usual or preferred ways of rubber coating fabric. It is also obvious that some degree of twist may be given to the individual strands if desired providing this does not materially detract from the flexibility of the cord and also that one or more strands without twist may be combined with one or more twisted-strands, or yarns, or plied yarns, making what may be termed a combination cord. It is also with- ,in the spirit of my invention to twist a single strand, element or roving which may be of enlarged cross-section until a maximum tensile strength'consistent with maximum flexibility is attained and then associating the strand thus formed with a binding material in any of the ways above described. As therefore many apparently widely different embodiments of the invention may be made without departing from the spirit thereof, it is to be understood that I do not intend to limit myself to the specific form of the invention as set forth except as indlcated in'the appended claims.

Vulcanized rubber articles having strain resisting elements of the character above specified are more pliable and durable and are less expensive than previously known elements for the same purpose. The soft non-compacted arrangement of the fibres iii the cords diminishes their abrasive or cut ting action on one another and lessens tlie heating. These last named features are highly desirable in tires, blow-outs being attributed to fibre cutting and heating being ascribed to the rubbing of the fibres upon one another. The strain resisting elements of the present invention require less fibrous material to furnish the required tensile t ength than rior cords or warp yarns, shorter staple cotton may be used. and in their manufacture expensive and time consuming operations are eliminated. In short, the present invention provides a better strain Twi ting vlemvn't for vulcanized runner arti: le at lens Post.

llm'liig thus lli'fit'l'lllttl my invention What l ('llllil! nml desire to pron-wt lay Letters Put-- em i z l. A l'nlirilreintnrccnimt for rubber tires having v4min resisting: elements consisting of a plurality of unspun roviugs twisted lmmely together.

vulcanized rubber article the strain resisting elements of which consist of loosely twisted fibres.

:3. A vulcanized rubber article the strain resisting elements of which consist of :1 pin rality of soft fibrous strands twisted loosely together.

4. A \lllfllnlZt'tl rulilier article thestrain res l ting elements of which consist of a plu- I'Ptlit:, of substantially untwisted rovings.

5., A vulcanized rubber articlethe strain resisting: elements of which consist of a pinrality ol' unspun rovings twisted loosely t0- getiier.

Signed at New York county of New York, State of New York. this 11th day of Octoher, 1918;

ALFRED E. JURY.