902 



THE INDIA RUBBER WORLD 



Seitember 1, 1921 



Circular Looms for \\^eaving Tubular Fabrics' 



CIRCULAR or tubular weaving is a manufacturing process con- 

 ducted in mechanical rubber goiKls factories as well as in 

 those devoted to the manufacture of cotton and linen fire 

 hose only. A hose protected by a heavy woven jacket is proof 

 against heavier bursting pressure and more severe external 

 abuse than one not so protected. The method of circular weaving 

 is employed in the manufacture, in continuous lengths, not only 

 of fire hose, but of steam, air, garden, and suction hose, and as 

 an outer cover to reinforce heavy-duty hose for various purposes. 



A circular loom is a very compact and ingenious mechanism 

 and the process of weaving is interesting and fascinating. The 

 installation usually constitutes a distinct department in a rubber 

 plant, with looms and creels set either on the same floor level, 

 as seen in Fig. 1, or with looms on a gallery or mezzanine floor 

 above t!-.e creels. 



Two sizes of circular looms are manufactured, the larger hav- 

 ing a range of output extending from the smallest diameters of 

 fabric hose jacket up to eight inches, while the smaller has a 

 capacity up to two inches in diameter. Within the limit of its 

 capacitj-, either loom will weave hose jackets of varying fineness 

 of weave, depending upon the yarn used and the number of picks 

 of weft per inch. In each machine is a spacious central tubular 

 column through the weaving center of which such articles as steam 

 or air hose, electric cables, etc., may be passed for insulat- 

 ing or covering purposes. In a similar manner the outer jacket 

 of double-jacket fire hose may be woven over the inner one in 

 continuous lengths, one jacket being woven right-hand, and the 

 other left-hand, to prevent twisting of the hose under pressure. 

 DESCRIPTION OF LOOM AND PARTS 



The plan of a circular loom, and arrangement of its principal 

 parts is approximately circular. A side view shows a heavy iron 

 base plate with upright columns supporting a series of four 

 circular platforms or galleries. The lowest platform carries a 

 cam-actuated mechanism for operating the heddles, the second 

 and third platforms carry the shuttles and shuttle guides, while 

 the top plate completes the framework, supporting the take-off 

 bridge, and protecting the operator from contact with the moving 

 parts. All of the mechanism is arranged compactly and as near 

 the base as possible to give stability, make the shuttle and weaving 



Fig. 1. Circular Loom Equipped with Creels, Motor-Urive, 

 Off Rolls and Production Indicator, for Weaving 

 Small-Diameter Hose 



pin readily accessible to the operator, and bring the whole weav- 

 ing operation into full view. 



^The information and illustrations used in this article were obtained 

 from John Royle & Sons, Patcrson, New Jersey. 



CAM-OPERATED HEDDLE MOTION 

 The sheds of warp are reversed at each heddle section in 

 precise conformity with the travel of the shuttles around their 

 circular track, through mechanism controlled by the action of a 

 large horizontal cam revolving about the central axis of the loom 

 in unison with the travel of the shuttles. On the under side of 

 this cam a smoothly-machined channel engages, at each heddle 

 section, a hardened-steel roller. Each roller is attached to a rack- 

 and-pinion unit, which in turn operates a rocking-arm mechanism 

 imparting the up-and-down motion to the two frames of its heddle 

 section. 



A distinctive feature ot 

 the heddle motion is its 

 gentleness in opening the 

 warp sheds. The sheds 

 move rapidly at the middle 

 of their travel, but start 

 and stop very slowly, 

 thereby avoiding shock to 

 working parts, and pre- 

 serving the original tensile 

 strength of the warp yarn. 

 HEDDLES 



Each warp thread en- 

 ters the loom through the 

 eye of a separate heddle 

 and the number of warp 

 threads that can be woven 

 into a fabric jacket is 

 limited by the number of 

 heddles provided. Each 

 heddle section comprises 

 two rectangular metal 

 frames, one inner and one 

 outer — see Fig, 2 — which are given an opposed up-and-down 

 motion by the cam-operated mechanism described below. The 

 warp is thus divided at each heddle section into two sheds 

 which reverse their positions following the passage of one shuttle, 

 and preceding the arrival of the other. 



WARP TENSION EQUALIZER 

 The entire body of warp, after leaving the creels, 

 is separated into 16 equal divisions corresponding to 

 the number of heddle sections. At the base of the 

 loom every thread is passed one or more times around 

 a friction surfaced roll, one roll for each section of 

 warp. These 16 rolls encircle the base of the machine 

 and are suitably geared together to insure precise 

 uniformity of rotation, thereby imparting even degree 

 of tension and even rate of feed to all of the warp 

 threads. A friction drum, geared to the train of rolls, 

 permits the operator to control the tension of all the 

 warp threads from a single adjusting device. 

 TAKE-UPS 

 After leaving the tension-equalizers the warp threads 

 pass vertically upward through the take-up levers be- 

 fore entering the heddles. There is a take-up section 

 for every heddle section, and each is a complete unit 

 secured to the loom frame by a pivoted construction that 

 permits its being dropped bodily downward from its 

 normal position shown in Fig. 3, to that illustrated in 

 When a cop is to be renewed, two or more take-up 

 sections are lowered, thereby slackening as many warp threads as 

 may be necessary to permit easy withdrawal of the empty spindle, 

 and insertion of the full cop. 



Fig. 2. Heddles in Frame 



Take- 



Fig. 4. 



