The fine bobbin and fly frame

does not differ e entially from the preceding machine. The rovings from the coarse bobbin and fly frame are placed in their bobbins in a frame called the creel , behind and above the roller beam, two bobbins being allowed for one fluted portion of the rollers. These rovings are united into one, so as to increase the uniformity of the slivers. The invention of the beautiful machine above described is due to Me rs. Cocker and Higgins of Manchester, and as lately improved by Henry Houldsworth, junr. Esq., it may be considered the most ingeniously combined apparatus in the whole range of productive industry. In the fine roving frame the sliver is twisted in the contrary direction to that of the coarse roving frame. For this reason the position of the cone is reversed, so as to present in succe ion to the band or strap, diameters continually greater, in order that the rotation of the bobbins may be accelerated in proportion as their size is increased, because here the flyer and the bobbin turn in the same direction, and the winding-on is effected by the prece ion of the bobbin; but if the winding-on took place by its falling behind, as in the coarse bobbin and fly frame, that is, if the flyer turned le quickly than the bobbin, the rotatory speed of the bobbin would be uniformly retarded; in which case the cone would be disposed as in the coarse frame. When by any means whatever an uniform length of thread is delivered by the rollers in a given time, the bobbin must wind it up as it is given out, and must therefore turn with a speed decreasing with the increase of its diameter by succe ive layers of thread. Hence proceeds the proposition, that the velocity of the bobbin must be in the inverse ratio of its diameter, as already explained. With respect to the bobbin and fly frame, the twist is given to the sliver by means of a spindle or flyer which turns in the same direction with the bobbin, but quicker or slower than it, which establishes two predicaments. The first case is where the flyer turns faster than the bobbin. Here the winding-on goes in advance, as in the coarse roving frame, or as in throstle spinning, where the yarn is wound on merely in consequence of the friction of the lower disc or washer of the bobbin upon the copping rail, and of the drag of the yarn. The second case is where the flyer revolves more slowly than the bobbin. Here the winding goes on in arrear, and as the bobbin turns faster, it must receive a peculiar motion, which is uniformly retarded in the ratio of its increase of diameter. This is the case with the fine bobbin and fly frame. When the cone is placed as in fig. 332 , the winding-on, in either the coarse or fine frame, results from the difference, whether greater or le , between the rotatory speed of the flyer and bobbin. The motion of the bobbin and spindle is simultaneous, and takes place in the same direction, with a difference varying more or le with the varying diameters of the bobbins. To render the matter still clearer, suppose for a moment the spindle to be motionle , then the bobbin must revolve with such a speed, as to lap-on the roving as fast as the rollers deliver it. The sliver comes forward uniformly; but the bobbin, by its increase of diameter, must revolve with a speed progre ively slower. Now, suppose the spindle set a-whirling, it is obvious that the bobbin must add to the movement requisite for winding-on the sliver, that of the spindle in the case of winding-on in arrear, or when it follows the flyers, and subtract its own motion from the twisting motion of the spindles, in the case of winding-on in advance, that is, when the bobbin precedes or turns faster than the flyers; for the diameter of the bobbin being 1 1 ⁄ 2 inch, 10 turns will take up 45 inches. Deducting these 10 turns from the 30 made by the spindle in the same time, there will remain for the effective movement of the bobbin only 20 turns; or when the diameter of the bobbin becomes 3 inches, 5 turns will take up the 45 inches, if the spindle be at rest; but if it makes 30 turns in the time, the effective velocity of the bobbin will be 25 turns, = 30 - 5. Hence in the fine bobbin and fly frame, the number of turns of the spindle, minus the number of turns made by the bobbin in equal times, is in the inverse ratio of the diameter of the bobbin. We thus perceive, that in the coarse frame the bobbin should move faster than the spindle, and that its speed should always diminish; whilst in the fine frame the bobbin should move slower than the spindle, but its speed should always increase. It is easy to conceive, therefore, why the cones are placed in reverse directions in the two machines. Not that this inversion is indispensably nece ary; the cone of the fine roving frame might, in fact, be placed like that of the coarse roving frame; but as the torsion of the roving becomes now considerable, and as on that account the bobbin would need to move still faster, which would consume a greater quantity of the moving power, it has been deemed more economical to give its movement an opposite direction. We mentioned that the twist of the sliver in the fine roving frame was the reverse of that in the coarse; this is a habit of the spinners, for which no good reason has been given. The divisions of the rack-bar, and the succe ive diameters of the cone, must be nicely adjusted to each other. The first thing to determine is how much the rack should advance for every layer or range of roving applied to the bobbin, in order that the cone may occupy such a place that the strap which regulates the pulley barrel may be at the proper diameter, and thus fulfil every condition. The extent of this progre ive movement of the rack depends upon the greater or le taper of the cone, and the increase which the diameter of the bobbin receives with every traverse, that is, every layer of roving laid on. But care should be taken not to taper the cone too rapidly, especially in the fine roving frame, because in its progre towards the smaller end, the strap would not slide with certainty and ease. We have already shown that the number of effective turns of the bobbin is inversely, as the diameter of the bobbin, or directly, as the succe ive diameters of the different points of the cone. H. Houldsworth, jun. Esq. has introduced a capital improvement into the bobbin and fly frame, by his differential or equation-box mechanism, and by his spring fingers, which, by pre ing the soft sliver upon the bobbin, cause at least a double quantity to be wound upon its barrel. With the description of his patent equation-box, I shall conclude the description of the bobbin and fly frame. Fig. 342. represents a portion of a fly frame with Mr. Houldsworth’s invention. a a a are the front drawing rollers, turning upon bearings in the top of the machine, and worked by a train of toothed wheels, in the way that drawing rollers are usually actuated. From the drawing rollers, the filaments of cotton or other material, b b , are brought down to, and pa ed through the arms of the flyers c c , mounted on the tops of the spindles d d , which spindles also carry the loose bobbins e e . In the ordinary mode of constructing such machines, the spindles are turned by cords or bands pa ing from a rotatory drum round their respective pulleys or whirls f , and the loose bobbins e , turn with them by the friction of their slight contact to the spindle, as before said; in the improved machine, however, the movements of the spindles and the bobbins are independent and distinct from each other, being actuated from different sources. The main shaft of the engine g , turned by a band and rigger A as usual, communicates motion by a train of wheels h , through the shaft i , to the drawing rollers at the reverse end of the machine, and causes them to deliver the filaments to be twisted. Upon the main shaft g , is mounted a cylindrical hollow box or drum-pulley, whence one cord pa es to drive the whirls and spindles f and d , and another to drive the bobbins e . IMG:4147767755307473660_illo0363.png:Fly frame This cylindrical box pulley is made in two parts, k and l , and slipped upon the axle with a toothed wheel m , intervening between them. The box and wheel are shewn detached in fig. 343. , and partly in section at fig. 344. That portion of the box with its pulley marked l , is fixed to the shaft g ; but the other part of the box and its pulley k , and the toothed wheel m , slide loosely round upon the shaft g , and when brought in contact and confined by a fixed collar n , as in the machine shewn at fig. 342. , they constitute two distinct pullies, one being intended to actuate the spindles, and the other the bobbins. In the web of the wheel m , a small bevel pinion o , is mounted upon an axle standing at right angles to the shaft g , which pinion is intended to take into the two bevel pinions p and q , respectively fixed upon bo es, embracing the shaft in the interior of the boxes k and l . Now it being remembered that the pinion q , and its box l , are fixed to the shaft g , and turn with it, if the loose wheel m be independently turned upon the shaft, with a different velocity, its pinion o , taking into q , will be made to revolve upon its axle, and to drive the pinion p , and pulley box k , in the same direction as the wheel m ; and this rotatory movement of the box k and wheel m , may be faster or slower than the shaft g , and box l , according to the velocity with which the wheel m is turned. Having explained the construction of the box pullies k and l , which are the peculiar features of novelty claimed under this patent, their office and advantage will be seen by describing the general movements of the machine. The main shaft g , being turned by the band and rigger A , as above said, the train of wheels h , connected with it, drives the shaft i , which at its reverse end has a pinion (not seen in the figure,) that actuates the whole series of drawing rollers a . Upon the shaft i there is a sliding pulley r , carrying a band s , which pa es down to a tension pulley t , and is kept distended by a weight. This band s , in its descent, comes in contact with the surface of the cone u , and causes the cone to revolve by the friction of the band running against it. The pulley r is progre ively slidden along the shaft i , by means of a rack and weight not shewn, but well understood as common in these kind of machines, and which movement of the pulley is for the purpose of progre ively shifting the band s from the smaller to the larger diameter of the cone, in order that the speed of its rotation may gradually diminish as the bobbins fill by the winding-on of the yarns. At the end of the axle of the cone u a small pinion v is fixed, which takes into the teeth of the loose wheel m , and, as the cone turns, drives the wheel m round upon the shaft g , with a speed dependent always upon the rapidity of the rotation of the cone. Now the box pulley l , being fixed to the main shaft g , turns with one uniform speed, and by cords pa ing from it over guides to the whorls f , drives all the spindles and flyers, which twist the yarns with one continued uniform velocity; but the box pulley k , being loose upon the shaft, and actuated by the bevel pinions within, as described, is made to revolve by the rotation of the wheel m , independent of the shaft, and with a different speed from the pulley box l ; cords pa ing from this pulley box k , over guides to small pullies under the bobbins, communicate the motion, whatever it may be, of the pulley box k , to the bobbins, and cause them to turn, and to take up or wind the yarn with a speed derived from this source, independent of, and different from, the speed of the spindle and flyer which twist the yarn. It will now be perceived, that these parts being all adjusted to accommodate the taking up movements to the twisting or spinning of any particular quality of yarn intended to be produced, any variations between the velocities of the spinning and taking up, which another quality of yarn may require, can easily be effected, by merely changing the pinion v , for one with a different number of teeth, which will cause the wheel m , and the pulley box k , to drive the bobbins faster or slower, as would be required in winding-on fine or coarse yarn, the speed of the twisting or spinning being the same. The rovings or spongy cords, of greater or le tenuity, made on the bobbin and fly, or tube roving frame, are either spun immediately into firm cohesive yarn, or receive a further preparation proce in the stretching frame, which is, in fact, merely a mule-jenny, without the second draught and second speed, and therefore need not be described at present, as it will be in its place afterwards. The finishing machines of a cotton mill, which spin the cohesive yarn, are of two cla es; 1. the water-twist or throstle, in which the twisting and winding are performed simultaneously upon progre ive portions of the roving; and, 2. the mule, in which the thread is drawn out and stretched, with little twist, till a certain length of about 5 feet is extended, then the torsion is completed, and the finished thread is immediately wound upon the spindles into double conical coils called cops. IMG:4147767755307473660_illo0365.png:Throstle The water-twist frame, so called by its inventor, Sir R. Ark wright, because it was first driven by water, is now generally superseded by the throstle frame, in which the mechanical spinning fingers, so to speak, are e entially the same, but the mode of communicating the motion of the mill-geering to them is somewhat different. Fig. 345. exhibits a vertical section of the throstle. This machine is double, po e ing upon each side of its frame, a row of spindles with all their subsidiary parts. The bobbins, filled with rovings from the bobbin and fly, or the tube frame, are set up in the creel a a , in two ranges, b , c , d , are the three usual pairs of drawing rollers, through which the yarn is attenuated to the proper degree of finene , upon the principles already explained. At its escape from the front rollers, every thread runs through a guide eyelet e of wire, which gives it the vertical direction down towards the spindles f , g . The spindles which perform at once and uninterruptedly the twisting and winding-on of the thread delivered by the rollers, are usually made of steel, and tempered at their lower ends. They stand at g in steps, pa at v through a bra bush or collet which keeps them upright, and revolve with remarkable speed upon their axes. The bobbins h , destined to take up the yarn as it is spun, are stuck loosely upon the spindles, and rest independently of the rotation of the spindles upon the copping beam l , with a leather washer between. Upon the top of the spindles an iron-wire fork, called a fly or flyer, i , k , is made fast by a left-hand screw, and has one of its forks turned round at the end into a little ring. The branch of the flyer at f is tubular, to allow the thread to pa through, and to escape by a little hole at its side, in order to reach the eyelet at the end of that fork. From this eyelet i , it proceeds directly to the bobbin. By the twirling of the spindle, the twisting of the portion of thread between the front roller d , and the nozzle f , is effected. The winding-on takes place in the following way:—Since the bobbin has no other connection with the spindle than that of the thread, it would but for it remain entirely motionle , relatively to the spindle. But the bobbin is pulled after it by the thread, so that it must follow the rotation of the spindle and fly. When we consider that the thread is pinched by the front roller d , and is thereby kept fully upon the stretch, we perceive that the rotation of the bobbin must be the result. Suppose now the tension to be suspended for an instant, while the rollers d , deliver, for example, one inch of yarn. The inertia or weight of the bobbin, and its friction upon the copping beam l , by means of the leather washer, will, under this circumstance, cause the bobbin to hang back in a state of rest, till the said inch of yarn be wound on by the whirling of the fly i , and the former tension be restored. The delivery of the yarn by the drawing rollers, however, does not take place inch after inch, by starts, but at a certain continuous rate; whence results a continuous retardation or loitering, so to speak, of the bobbins behind the spindles, just to such an amount that the delivered yarn is wound up at the same time during the rotation. This proce in spinning is e entially the same as what occurs in the fine bobbin and fly frame, but is here simplified, as the retardation regulates itself according to the diameter of the bobbin by the drag of the thread. In the fly frame the employment of this tension is impo ible, because the roving has too little cohesion to bear the strain; and hence it is nece ary to give the bobbins that independent movement of rotation which so complicates this machine. The up and down motion of the bobbins along the spindles, which is required for the equal distribution of the yarn, and must have the same range as the length of the bobbin barrels, is performed by the following mechanism. Every copping rail l , is made fast to a bar m , and this, which slides in a vertical groove or slot at the end of the frame, is connected by a rod n , with an equal-armed, moveable lever o . The rod p carries a weight r , suspended from this lever; another rod q , connects the great lever o with a smaller one s , t , upon which a heart-shaped disc or pulley u , works from below at t . By the rotation of the disc u , the arm t , being pre ed constantly down upon it by the reaction, the weight r must alternately rise and fall; and thus the copping rail l must obviously move with the bobbins h up and down; the bobbins upon one side of the frame rising, as those upon the other sink. Strictly considered, this copping motion should become slower as the winding-on proceeds, as in the fly roving frame; but, on account of the smallne of the finished thread, this construction, which would render the machine complicated, is without inconvenience neglected, with the result merely that the coils of the yarn are succe ively more sparsely laid on, as the diameter of the bobbin increases. The movement of the whole machine proceeds from the shaft of a horizontal drum, which drives the spindles by means of the endle bands x x . Each spindle is mounted with a small pulley or wharf w , at its lower part, and a particular band, which goes round that wharf or whorl, and the drum y . The bands are not drawn tense, but hang down in a somewhat slanting direction, being kept distended only by their own weight. Thus every spindle, when its thread breaks, can readily be stopt alone, by applying a slight pre ure with the hand or knee, the band meanwhile gliding loosely round the whorl. The velocities of rotation of the three drawing rollers are, according to this arrangement, in the proportion of 1: 1 1 ⁄ 2 : 8; and as their diameters are the same, namely, one inch, the elongation of the yarn in spinning is eight-fold. If, for example, the roving was of the number 4 1 ⁄ 2 , the yarn would become No. 36. The extension of the thread may be changed by changing the wheels of the drawing rollers. To perceive the power of this change, let us put, for example, in the place of the 18-toothed wheel of the back rollers, a wheel with 16 teeth; we shall find that the elongation will amount, in that case, only to 7 1 ⁄ 2 times, whence the number of the yarn would come out 32 = 7 1 ⁄ 2  × 4 1 ⁄ 2 . The extension by the throstle is extremely various; it amounts, in some cases, to only 4 times; at others to 10, 12, or even 15. The copping motion of the bobbins is produced in consequence of a bevel pinion working in a small bevel wheel upon an upright shaft; while this wheel gives a slow motion by means of a worm screw to the wheel of the heart-shaped pulley u , fig. 345. The driving pulley makes about 600 turns in a minute; and as the diameter of the drum y , fig. 345. , is six times the diameter of the spindle wharves w , it will give 3600 turns to the spindle in that time. If the pulley be driven faster, for example 700 times in a minute, it will increase the revolutions of the spindles to 4200. The degree of twist which will be thereby imparted to the yarn, depends, with like speed of spindles, upon the rate at which the soft yarn is delivered by the drawing rollers; for the quicker this delivery, the quicker is the winding-on, and the le twist goes into a given length of yarn. If, for example, the front rollers d , turn 24 times in a minute, giving out of course 72 inches of yarn in this time, upon which the 3600 revolutions of the spindle are expended, there will be 50 twists to every inch of yarn. By changing the wheel-work of fig. 345. , or by sticking greater or smaller wharves upon the spindles, the proportion between their velocity and that of the drawing rollers, and thence the degree of twist can be modified at pleasure. The number of spindles in a throstle frame 12 feet long, is about 60 on each side. The drawing rollers are coupled together as in the bobbin and fly frame, so that each row forms one continuous cylinder. There is a complete roller beam on each side; each of the rollers of the front row is pre ed by its top rollers with a weight of ten or twelve pounds; but those of the middle and back rows bear weights of only one pound. In the throstles, there is a guide bar which traverses a small way horizontally to the left and right, in front of the roller beam, to lead the thread along different points of the rollers, and thus prevent the leather of the top ones from being grooved by its constant pre ure in one line. For the service of 240 spindles, in two double frames, one young woman, and an a istant piecer are sufficient. They mend the broken ends, and replace the empty bobbins in the creel with full ones, and the full bobbins of the throstle by empty ones. The average quantity of yarn turned off in a week of 69 hours is about 24 hanks per spindle of 3 0′ s twist. Throstle yarn is of a firm wiry quality, adapted to the warps of fustians and other strong stuffs, as well as to the manufacture of stockings and sewing thread. There are many modifications of the throstle system besides the one above described; the most celebrated of which are Dan forth’s, called the American throstle, Montgomery’s, and Gore’s. I must refer for an account of them to my work entitled “The Cotton Manufacture of Great Britain,” where they are minutely described and illustrated with accurate figures.