Page:The New International Encyclopædia 1st ed. v. 12.djvu/505

* LOOM. 447 LOOM. all his time and money, and, as it did not come into general use until his patents had expired, he received no financial return for his labors. In 1808, however. Parliament voted him £10,000. It was said that he spent fully four times that sum in ])erfecting his loom. During the century after Cartwright's inven- tion the development of the loom received the attention of hundreds of inventors, and at the beginning of the twentieth century wc find a vast number of difi'erent types in operation, all embodying, however, the fundamental principles of the original. . The simplest type of modern power-loom is shown in Fig. 2. The looiU'frame supports two horizontal shafts. A, B, one above and a little back of the other and so geared together that the upper shaft, to which the power is applied, makes two revolutions to one of the lower. The upper shaft is supplied with two cranks, one at each end, near the frame, to which the lathe, 4, is attached with short connecting-rods, and as the shaft revolves it imparts to the lathe a recipro- cating motion as the latter swings on the pivot, 5, 5, at the bottom of the loom-frame. The lower 3 Fig. 2. power-loom. shaft is supplied with certain attachments called cams, near the centre, which work in contact with the loom-treadles, C, D; the latter are con- nected to the harness-frames, J";/, xy. suspended from a roller. 3. 3, above, and as the shaft re- volves first one is depressed and then the other, forming sheds with the warp as in the hand- loom. The lower shaft is also supplied with certain appliances, 6, 6, which act on two special rocker-shafts, 7, 7, one at each end of the loom, placed at right angles to and in a horizontal plane above the lower shaft and each having an arm. !t, to which is connected a picker-stick, g. (J ; these picker-sticks are so arranged that when the lower shaft revolves the action on the short rocker-shafts causes the picker-stick on one side to be jerked quickly toward the wnrp which is beinc woven and to throw tlie shittle from that side of the loom through the shed into the skuttle-hox, H, H, at the opposite end, where it remains until the filling is beaten up by the action of the lathe, and the harness change position, forming a new shed, when the second picker-.stick is acted on as was the first and the shuttle is driven back to its former position and the operation is repeated continuously. In this loom the warp is not stretched directly from the ii:arp-beam, 1, to the cloth-roll, 2, as in the hand-loom, but is carried upward at an angle from the warp-bcam over a support called the uhip-roll, a, from which it is stretched, through the harness and reed — which are held firmly in the lathe by the hand-rail, b — to the hreast-beain, d, over which the cloth passes downward to the cloth roll; it will he seen that by this arrangement the loom is made to take up much less space than it would in any other form. The modern power-loom also combines a number of appliances which were made necessary by the application of power and which make it possible for the weaver to keep a number of looms running, while the hand-weaver could run but one. Of these special attachments may be mentioned the filling-stop motion, which automatically causes the loom to stop, should the filling become exhausted in the shuttle, or break; the shuttle-protector, which is so arranged that should the shuttle for any reason fail to reach its place in the shuttle-box to which it has been driven, the loom is stopped and held so that the lathe will not cause any of the warp- threads to be broken should the shuttle happen to be caught in the shed and the loom not stop; the automatic take-up and let-off motions, which let the warp unroll from the warp-beam at the re- quired speed and wind up the woven cloth automatically, regulating the num- ber of filling-threads to the inch. There has also recently been perfected the warp- stop motion, which is arranged to act on the driving motion of the loom and to cause the loom to stop immediately should one of the threads of the warp become broken. As labor is a large item in the cost of production, much experimenting has been done to perfect a loom which would either change an empty shuttle for a full one automatically, or else furnish a full bobbin of yarn to the empty shuttle with- out the loom stopping. The Xorlhrop loom. Fig. 3, is the only one which has proved practical enough to be installed in any number as yet; there were over 70.000 of these in opera- tion at the beginning of 1003, though the inven- tion only dates from 1894. In this loom the loom-shuttle and one of the shuttle-boxes are made without any bottom, and above this shuttle-box is arranged .a magazine or hopper which is kept supplied with a large number of full bobbins; as the filling in the shuttle nuis out, the mechanism of the loom so acts on one of the fresh bobbins of yarn that it is forced downward into the shuttle and in turn forces the empty bobbin out through the holes in the bottom of the shuttle and the shuttle-box. and the loom continues to run as if no change had been made. The above principle has as yet only been ap- plied to looms weaving the simpler kinds of cot- ton fabrics, and only to weave fabrics when there is to be but one filling in kind or color through- I