Textile fabric for tubing-envelopes
US 532902 A
Description (OCR text may contain errors)
(No mam. I
J. F. PALMER.
TEXTILE FABRIC FOR TUBING E-NVELOPES N0. 532,902. d Patented Jan. 22,1895.
Ziy7? J65. @We72%71 4107272 azvwen Maw W jected to internal pressure, to supply an envelope to constitute the strain-resisting me-' iNrE TATTES ATENT FFl C JOHN F. PALMER, OF RIVERSIDE, ILLINOIS.
SPECIFICATION forming part of Letters Patent No. 532,902, dated January 22, 1895. Application filed January 6, 1894. Serial No. 495.941. (No model.)
To all whom it may concern:
Be it known that I, JOHN F. PALMER, a citizen of the United States, residing at Riverside, in the county of Cook and State of Illinois, have invented a new and useful Improvement in Textile Fabrics for Tubing-Enyelopes, of which the following is a specificaion.
My invention relates to an improvement in textile fabrics and is more particularly dirooted to an improvement in fabrics for use as an envelope for tubing of rubber or the like.
It is well-known that rubber has slight strain-resisting properties in any direction excepting that involving a compressive strain, and it is therefore the uniform practice in making tubing of rubber, or articles of other shape than tubular, when they are to be subdium, of a material which while flexible is substantially non-elastic and sufficiently strong to hold the internal pressure referred to. Heretofore, and until a recent invention of my own presently referred to, buttwo modes of providing a strengthening medium have been practiced, namely, to wrap canvas, in strips or otherwise, about the tube, or to wind spirally about its threads, usually of flexible fibrous material, such as linen, although under some conditions wire has been employed. For many reasons canvas or any woven fabric of a similar nature, unless made to have the special characteristic involved in the inventionhereinafter claimed,is objectionable as an envelope for rubber tubing, especially if the tubing is to be employed under conditions where internal and external pressures are applied, or under conditions where the tubing while under tension by reason of internal pressure is to be subjected to vibration, as in the case of water hose or bicycle pneumatic tires. It is found that the crossing threads of the canvas being under tension in all directions abrade each other with consequent destruction of the fabric. It is found also to be practically impossible to establish a limit of extensibility in the envelope, thereby to limit the distention of the air tube with certainty where a material is employed, which, like canvas, contains strainresisting threads all of which present awavy line;
As a means of overcoming the objections to the use of canvas and at the same time to avoid the inconvenience incident tothe use of threads alone and unprovided with any means for insuring a uniformity in their relation to each other, the invention set forth in Letters Patent of the United States granted to me March 7, 1893, No. 493,220, was contrived, and the product there set forth is found entirely to answer the purposes of its invention. It has gone into extensive use and is found to present a substantially per.- fect envelope for tubing and the like, especially in connection with bicycle pneumatic tires, and to give to the tube a strain-resisting property greater than has heretofore been considered practicable with the same thickness of rubber in the wall of the tube. The essential characteristic of the product set forth in said Letters Patent of March 7,1893, lies in the fact that the strai n-resist-in g threads which constitute the envelope do not contact with each other in such a manner that the tension upon either under the vibration to which the product is subjected will serve to abrade the others, or cause its abrasion by the others; that the strain-resisting threads present a continuous straight as distinguished from a wavy line, so that the utmost limit of their tension can be obtained at all times; that the threads thus constituting the strainresisting medium are applied several at a time and during the application and after application are caused by the interposed rubber to maintain a substantial uniformity in their distance from each other, and, what is much more essential, a substantially parallel relation with each other. As explained in the course of the application for said Letters Patent the fabric there disclosed can be in a measure and for some purposes with advantage produced without the employment of rubber as the medium for holding the threads together and apart, and such an improvement is found in the invention hereinafter claimed, a description of which is as follows, reference being had to the accompanying drawings, in which- Figure 1 is a plan view of a sheet of textile material forming partof my invention,
Fig. 2, a view illustrating the manner of applying two such sheets together to constitute an envelope; and Fig. 3 is a view of a section of hose, or other rubber tubing, showing the manner in which an envelope involving my improvement is applied.
The fabric is produced by weaving through parallel warp threads of asubstantially non extensible material, such as linen, occasional woof threads of a material comparatively easy of destruction by breaking or otherwise and preferably loose, whereby the tension upon the warp threads does not produce at the point of crossing of the woof threads a variation in the direction of the warp threads. With the warp threads of linen the woof threads will ordinarily be of cotton or wool and usually also much thinner than the Warp threads; but the Woof threads may also be of linen but thinner than the warp threads and hence more easily broken, or may be of linen threads of the kind called rotten threads, especially prepared or otherwise. I do not limit my invention to any particular material in this regard, nor to any particular relative dimension, so long as the characteristic remains that the woof threads are so applied as not to interfere with the distention into a straight line of the warp threads and are relatively fragile.
A represents the warp threads and B represents the woof threads, the latter being disposed as indicated in Fig. 1 preferably some distance apart, although the invention is not limited to any particular distance, nor to the specific arrangement illustrated in the drawlngs.
It will be obvious that a fabric constituted as illustrated in Fig. 1 of a single sheet will have great strain-resisting property in the direction longitudinally of the Warp threads, and will have substantially no strain-resisting property in other directions, the amount of strain-resistin g property being merely that found in the woof threads which as explained is preferably very slight. Hence, as an envelope fortubing, when applied in a single sheet such a fabric is of little value. It is necessarily applied in such manner that the threads shall extend diagonally of the tube so that both lateral and longitudinal distention of the tube is readily permitted. In order to limit the distensibility of the tube both radiallyand longitudinally two strips of such fabric are employed, being applied as indicated in Fig. 2 in such a manner that the warp threads of the respective fabrics cross each other at a greater or less angle. The fabric may be made by laying one strip, preferably cut diagonally of the warp fiber, upon another strip similarly cut and in such manner that the fibers of one strip present an angle to the fibers of the other strip, and the double ply of fabric thus obtained placed upon the tube; and in the case of a straight length of tubing and other articles of rubber this mode of procedure may be it in the opposite direction with the edges abutting without overlapping as in the case of the first strip. It is usual to apply the first strip to the inner rubber tube before the latter is vulcanized, then to apply the second strip, and thereupon to apply a second or outer tube of rubber also unvulcanized, the Whole being then placed in the vulcanizing oven where the usual pressure is applied to cause the rubber tubing'to become vulcanized and the threads to become thoroughly united to the rubber. Becoming thus united to the rubber the threads are caused to maintain their relation to each other to the extent permitted by the elasticity of the rubber, and the product thereupon has substantially the attributes found in the fabric which forms the subject of my said Letters Patent granted March 7, 1893. The woof threads, having served their purpose of holding the warp threads in proper relation to each other during the winding of the fabric upon the tube, may be and sometimes are destroyed in vulcanizing; and even if they are not their fragility is such as topermit them to break readily under tensile strain laterally of the Warp threads. This is an advantage rather than otherwise, as it is important that the elasticity of the rubber in all directions, excepting that parallel with the warp threads of the two plies of fabric, shall in no way be materially reduced.
In some cases it is desirable before applying the plies of fabric to the tubing to saturate them with rubber after the manner of the production of binding cloth, and this step is contemplated as part of this invention, although it is not essential. If desired before applying the fabric to the tubing it may be laid upon a sheet usually of thin unvulcanized rubber and pressed therein, thus producing the fabric which forms the subject of my granted Letters Patent; and if desired it may be the practice to apply both plies of fabric separately to strips of rubber, or to opposite sides of a single strip of rubber before applying them to the tube, the fragile woof threads employed serving to maintain the Warp threads in their proper relation to each other when introducing them into the sheet. These procedures when practiced are to be understood as included in the invention herein set forth.
In Fig. 3, 0 represents the inner tube, D the first ply of fabric, E the second ply of fabric and F the outer tube. It will be understood of course that as many plies of fabric D E may be employed as desired, and in making the tube the numbers of plies and outer tubes F may be varied according to the necessity of the case.
What I claim as new, and desire to secure by Letters Patent, is
1. In a fabric for tubing-envelopes, having fibrous warp-threads, relatively fragile woofthreads so applied as not to deflect thewarpthreads when under tension and afiording a temporary or readily destructible medium for holding said warp-threads in position, substantially as described.
2. A fabric for tubing-envelopes, comprising fibrous warp-threads embedded in rubber, and relatively fragile woof-threads affording tension, and embedding the whole in rubber, 25
substantially as described.
JOHN F. PALMER. In presence of M. J. FROST,
W. N. WILLIAMS.