Fly frameThis cylindrical box pulley is made in two parts,kandl, and slipped upon the axle with a toothed wheelm, intervening between them. The box and wheel are shewn detached infig.343., and partly in section atfig.344.That portion of the box with its pulley markedl, is fixed to the shaftg; but the other part of the box and its pulleyk, and the toothed wheelm, slide loosely round upon the shaftg, and when brought in contact and confined by a fixed collarn, as in the machine shewn atfig.342., they constitute two distinct pullies, one being intended to actuate the spindles, and the other the bobbins.In the web of the wheelm, a small bevel piniono, is mounted upon an axle standing at right angles to the shaftg, which pinion is intended to take into the two bevel pinionspandq, respectively fixed upon bosses, embracing the shaft in the interior of the boxeskandl. Now it being remembered that the pinionq, and its boxl, are fixed to the shaftg, and turn with it, if the loose wheelmbe independently turned upon the shaft, with a different velocity, its piniono, taking intoq, will be made to revolve upon its axle, and to drive the pinionp, and pulley boxk, in the same direction as the wheelm; and this rotatory movement of the boxkand wheelm, may be faster or slower than the shaftg, and boxl, according to the velocity with which the wheelmis turned.Having explained the construction of the box pullieskandl, 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 shaftg, being turned by the band and riggerA, as above said, the train of wheelsh, connected with it, drives the shafti, which at its reverse end has a pinion (not seen in the figure,) that actuates the whole series of drawing rollersa. Upon the shaftithere is a sliding pulleyr, carrying a bands, which passes down to a tension pulleyt, and is kept distended by a weight. This bands, in its descent, comes in contact with the surface of the coneu, and causes the cone to revolve by the friction of the band running against it. The pulleyris progressively slidden along the shafti, 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 progressively shifting the bandsfrom 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 coneua small pinionvis fixed, which takes into the teeth of the loose wheelm, and, as the cone turns, drives the wheelmround upon the shaftg, with a speed dependent always upon the rapidity of the rotation of the cone. Now the box pulleyl, being fixed to the main shaftg, turns with one uniform speed, and by cords passing from it over guides to the whorlsf, drives all the spindles and flyers, which twist the yarns with one continued uniform velocity; but the box pulleyk,being loose upon the shaft, and actuated by the bevel pinions within, as described, is made to revolve by the rotation of the wheelm, independent of the shaft, and with a different speed from the pulley boxl; cords passing from this pulley boxk, over guides to small pullies under the bobbins, communicate the motion, whatever it may be, of the pulley boxk, 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 pinionv, for one with a different number of teeth, which will cause the wheelm, and the pulley boxk, 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 less tenuity, made on the bobbin and fly, or tube roving frame, are either spun immediately into firm cohesive yarn, or receive a further preparation process 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.Thefinishing machinesof a cotton mill, which spin the cohesive yarn, are of two classes; 1. the water-twist or throstle, in which the twisting and winding are performed simultaneously upon progressive 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.ThrostleThe water-twist frame, so called by its inventor, Sir R. Arkwright, 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 essentially 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, possessing 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 creela 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 fineness, upon the principles already explained. At its escape from the front rollers, every thread runs through a guide eyeleteof wire, which gives it the vertical direction down towards the spindlesf,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 atgin steps, pass atvthrough a brass bush or collet which keeps them upright, and revolve with remarkable speed upon their axes. The bobbinsh, 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 beaml, 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 atfis tubular, to allow the thread to pass 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 eyeleti, it proceeds directly to the bobbin. By the twirling of the spindle, the twisting of the portion of thread between the front rollerd, and the nozzlef, 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 motionless, 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 rollerd, 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 rollersd, deliver, for example, one inch of yarn. The inertia or weight of the bobbin, and its friction upon the copping beaml, 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 flyi, 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 process in spinning is essentially 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 employmentof this tension is impossible, because the roving has too little cohesion to bear the strain; and hence it is necessary 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 raill, is made fast to a barm, and this, which slides in a vertical groove or slot at the end of the frame, is connected by a rodn, with an equal-armed, moveable levero. The rodpcarries a weightr, suspended from this lever; another rodq, connects the great leverowith a smaller ones,t, upon which a heart-shaped disc or pulleyu, works from below att. By the rotation of the discu, the armt, being pressed constantly down upon it by the reaction, the weightrmust alternately rise and fall; and thus the copping raillmust obviously move with the bobbinshup 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 smallness 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 successively 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 endless bandsx x. Each spindle is mounted with a small pulley or wharfw, at its lower part, and a particular band, which goes round that wharf or whorl, and the drumy. 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 pressure 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 : 11⁄2: 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 41⁄2, 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 71⁄2times, whence the number of the yarn would come out 32 = 71⁄2× 41⁄2. 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 pulleyu,fig.345.The driving pulley makes about 600 turns in a minute; and as the diameter of the drumy,fig.345., is six times the diameter of the spindle wharvesw, 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 less twist goes into a given length of yarn. If, for example, the front rollersd, 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 offig.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 pressed by its top rollers with a weight of ten ortwelve 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 pressure in one line.For the service of 240 spindles, in two double frames, one young woman, and an assistant 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 30′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 Danforth’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.Mule-spinning.—The general principles of the mule have been already stated. This machine is so named because it is the offspring, so to speak, of two older machines, the jenny and the water-frame. A mule is mounted with from 240 to 1000 spindles, and spins of course as many threads.Hargreaves's jennyFig.346.represents the originaljennyof Hargreaves, by which one person was enabled to spin from 16 to 40 threads at once. The soft cords of rovings wound in double conical cops upon skewers were placed in the inclined frame atC; the spindles for first twisting and then winding-on the spun yarn were set upright in steps and bushes atA, being furnished near their lower ends with whorls, and endless cords, which were driven by passing round the long-revolving drum of tin plateE.Dis the clasp or clove, having a handle for lifting its upper jaw a little way, in order to allow a few inches of the soft roving to be introduced. The compound cloveDbeing now pushed forward upon its friction wheels toA, was next gradually drawn backward, while the spindles were made to revolve with proper speed by the right hand of the operative turning the flywheelB. Whenever onestretchwas thereby spun, the clove frame was slid home towardsA; the spindles being simultaneously whirled slowly to take up the yarn, which was laid on in a conical cop by the due depression of the faller wire atAwith the spinner’s left hand.Arkwright's water frameFig.347.is a diagram of Arkwright’s originalwater-framespinning machine, called afterwards thewater-twistframe. The rovings mounted upon bobbins in the creelA A, have their ends led through between the three sets of twin rollers belowB B, thence down through the eyelet hooks upon the end of the flyers of the spindlesC, and finally attached to their bobbins. The spindles being driven by the bandD Dupon their lower part, continuously twist and wind the finished yarn upon the bobbins; constituting the first unremitting automatic machine for spinning which the world ever saw.Hindostan spinsterContrast with the above admirable system, the primitive cotton wheel of India, as represented in the annexedfigure 348. By the aid of mechanical fingers, one Englishman at his mule can turn off daily more yarn and of far finer quality than 200 of the most diligent spinsters of Hindostan.MuleFig. 349 enlarged(195 kB)Fig.349., is a transverse section of the mule, in which its principal parts are shown.The machine consists of two main parts; a fixed one corresponding in some measure to the water-frame or throstle, and a moveable one corresponding to the jenny. The first contains in a suitable frame the drawing roller-beam and the chief moving machinery: the second, is called the carriage, in which the remainder of the moving mechanism and the spindles are mounted.The frame of the fixed part consists of two upright sides, and two or more intermediate parallel bearings, upon which the horizontal roller beama, the basis of the drawing rollers is supported,b,c,d, are the three ranges of fluted iron rollers;e,f,g, are the upper iron rollers covered with leather;h, the wooden wiper-rollers covered with flannel, which being occasionally rubbed with chalk, imparts some of it to the pressure rollers beneath, so as to prevent the cotton filaments adhering to them. The rollers are made throughoutthe whole length of the mule in portions containing six flutings, which are coupled together by squared ends fitted into square holes.The skewers upon which the bobbins containing the rovings from the bobbin and fly or stretching frame, are set up, are seen ata1,a1,a1, arranged in three rows in the creelz. The soft threads unwound from these bobbins, in their way to the drawing rollers, pass first through eyelets in the ends of the wire armsb1, then through the rings or eyes of the guide barw, and enter between the back pair of rollers. The number of these bobbins is equal to the number of spindles in the mule, and twice as great as the number of fluted portions of the rollers; for two threads are assigned to each portion.The carriage consists of two cast-iron side pieces, and several cast-iron intermediate similar pieces, such asf2, which all together are made fast to the planksb2,c2,d2. The top is covered in with the plankk2. The carriage runs by means of its cast-iron grooved wheels, upon the cast-iron railwayl2, which is fixed level on the floor.The spindles stand upon the carriage in a frame, which consists of two slant railsx2,x2, connected by two slender rodsy2, and which frame may be set more or less obliquely. The lower rail carries the brass steps for the points of the spindlesb3; upon the upper rail brass slips are fixed pierced with holes through which the tops of the spindles play. The spindles are as usual made of steel, perfectly straight, turned truly round, and are all arranged in one plane. To each of them a small wooden or cast-iron whorlg2is made fast. They are distributed into groups of 24, and the whorls are arranged at such different heights, that only two of them in each group are upon a level with each other. A small brass headh2, which every spindle has beneath the upper slant rail of the framex2, prevents their sitting down into the step, during their rotation, or sliding off their cop of yarn.c3are drums, mounted in the carriage in a plane at right angles to the plane in which the spindles are placed. At top they have a double groove for a cord to run in, and the motion which they receive from the great fly wheel, or rim of the mule (not visible in this view) they impart to the spindles. Such a drum is assigned to every 24 spindles; and therefore a mule of 480 spindles contains 20 drums. In the middle of the carriage is seen the horizontal pulleyk3, furnished with three grooves, which stands in a line with the drumsc3.The motion is given to the drumsc3, upon the right hand half of the carriage by a single endless band or cord which proceeds from the middle groove of the pulleyk3. The rotation of the spindles is produced by a slender cord, of which there are 12 upon each drumc3; because every such cord goes round the drum, and also every two wharves which stand at the same level upon the spindles. It is obvious that the drums, and consequently the spindles, must continue to revolve as long as the main rim of the mule is turned, whether the carriage be at rest or in motion upon its railway.If we suppose the carriage to be run in to its standing point, or to be pushed home to the spot from which it starts in spinning, its back plankd2will strike the postq3upon the fixed frame, and the points of the spindles will be close in front of the roller beam. The rollers now begin to turn and to deliver threads, which receive immediately a portion of their twist from the spindles; the carriage retires from the roller beam with somewhat greater speed than the surface speed of the front rollers, whereby the threads receive a certain degree of stretching, which affects most their thicker and less twisted portions, and thereby contributes greatly to the levelness of the yarn. When the carriage has run out to the end of its course, or has completed a stretch, the fluted rollers suddenly cease to revolve (and sometimes even beforehand, when a second stretch is to be made), but the spindles continue to whirl till the fully extended threads have received the proper seconder after-twist. Then the carriage must be put up, or run back towards the rollers, and the threads must be wound upon the spindles.This is the order of movements which belong to the mule. It has been shown how the rotation of the spindles is produced.For winding-on the yarn the carriage has a peculiar apparatus, which we shall now describe. In front of it, through the whole extent to the right hand as well as the left, a slender iron rod,d5, runs horizontally along, in a line somewhat higher than the middle of the copping portion of the spindles, and is supported by several props, such ase5. Upon each end of the two rods,d5, there is an arm,g5; and betwixt these arms an iron wire, called the copping wire,f5, is stretched, parallel with the rodd5. For the support of this wire, there are several slender bent armsh5extended from the rodd5at several points betwixt the straight armsg5. The rodd5has, besides a wooden handle at the place opposite to where the spinner stands, by which it can be readily grasped. This movement is applied at the left division of the machine, and it is communicated to the right by an apparatus which resembles a crane’s bill. The two arms,g5, in the middle of the machine, project over the rodsd5, and are connected by hinges with two vertical rodsj5, which hang together downwards in like manner with two armsi5, proceeding from a horizontal axisk5.By means of that apparatus the yarn is wound upon the spindles in the following manner. As long as the stretching and twisting go on, the threads form an obtuse angle with the spindles, and thereby slide continually over their smooth rounded tips during their revolution, without the possibility of coiling upon them. When, however, the spinning process is completed, the spinner seizes the carriage with his left hand and pushes it back towards the roller beam, while with his right hand he turns round the handle of the rim or fly wheel, and consequently the spindles. At the same time, by means of the handle upon the rodd5, he moves the copping-wire,f5, so that it presses down all the threads at once, and places them in a direction nearly perpendicular to the spindles; as shown by the dotted liney5. That this movement of the copping wire, however, may take place without injury to the yarn, it is necessary to turn the rim beforehand a little in the opposite direction, so that the threads may get uncoiled from the upper part of the spindles, and become slack; an operation called in technical language, thebacking off. The range upon which the threads should be wound, in order to form a conical cop upon the spindle, is hit by depressing the copping wire to various angles, nicely graduated by an experienced eye. This faller wire alone is not, however, sufficient for the purpose of winding-on a seemly cop, as there are always some loose threads which it cannot reach without breaking others.Another wire called thecounter-faller,l5, must be applied under the threads. It may be raised to an elevation limited by the angular piecep5; and is counterpoised by a very light weightm5, applied through the bent levern5, which turns upon the fulcrumo5. This wire, which applies but a gentle pressure, gives tension to all the threads, and brings them regularly into the height and range of the fallerf5. This wire must be raised once more, whenever the carriage approaches the roller beam. At this instant a new stretch commences; the rollers begin again to revolve, and the carriage resumes its former course. These motions are performed by the automatic machinery.There is a little eccentric pulley mechanism for moving the guide beam to and fro with the soft yarns, as they enter between the back rollers. On the right hand end of the back roller shaft, a worm screw is formed which works into the oblique teeth of a pinion attached to the end of the guide beam, in which there is a series of holes for the passage of the threads, two threads being assigned to each fluted roller. In the flat disc of the pinion, an eccentric pin stands up which takes into the jointed lever upon the end of the guide beam, and as it revolves, pushes that beam alternately to the left and the right by a space equal to its eccentricity. This motion is exceedingly slow, since for each revolution of the back roller, the pinion advances only by one tooth out of the 33 which are cut in its circumference.After counting the number of teeth in the different wheels and pinions of the mule, or measuring their relative diameters, it is easy to compute the extension and twist of the yarns; and when the last fineness is given to ascertain their marketable value. Let the ratio of speed between the three drawing rollers be 1 : 13⁄22: 71⁄2; and the diameter of the back and middle roller three quarters of an inch: that of the front roller one inch; in which case the drawing is thereby increased 11⁄3times, and 71⁄2× 11⁄3= 10. If the rovings in the creel bobbins have been No. 4. the yarn, after passing through the rollers, will be No. 40. By altering the change pinion (not visible in this view) the fineness may be changed within certain limits, by altering the relative speed of the rollers. For one revolution of the great rim or fly wheel of the mule, the front roller makes about 6-tenths of a turn, and delivers therefore 22·6 lines or 12ths of an inch of yarn, which, in consequence of the tenfold draught through the rollers, corresponds to 2·26 lines of roving fed in at the back rollers. The spindles or their whorls make about 66 revolutions for one turn of the rim. The pulleys or grooved wheels on which the carriage runs, perform 0·107 part of a turn while the rim makes one revolution, and move the carriage 24·1 lines upon its rails, the wheels being 6 inches in diameter.The 22·6 lines of soft yarn delivered by the front rollers, will be stretched 11⁄2lines by the carriage advancing 24·1 lines in the same time. Let the length of the railway, or of each stretch be 5 feet, the carriage will complete its course after 30 revolutions of the rim wheel, and the 5 feet length of yarn (of which 561⁄2inches issue from the drawing rollers, and 31⁄2inches proceed from the stretching) is, by the simultaneous whirling of the spindles, twisted 1980 times, being at the rate of 33 twists for every inch. The second twist, which the threads receive after the carriage has come to repose, is regulated according to the quality of the cotton wool, and the purpose for which the yarn is spun. For warp yarn of No. 40 or 50, for example, 6 or 8 turns of the rim wheel, that is, from 396 to 528 whirls of the spindles for the whole stretch, therefore from 7 to 9 twists per inch will be sufficient. The finished yarn thus receives from 40 to 42 twists per inch.One spinner attends to two mules, which face each other, so that he needs merely turn round in the spot where he stands, to find himself in the proper position for the other mule. For this reason the rim wheel and handle, by which he operates, are notplaced in the middle of the length of the machine, but about two fifths of the spindles are to the right hand and three fifths to the left; the rim wheel being towards his right hand. The carriage of the one mule is in the act of going out and spinning, while that of the other is finishing its twist, and being put up by the spinner.The quantity of yarn manufactured by a mule in a given time, depends directly upon the number of the spindles, and upon the time taken to complete every stretch of the carriage. Many circumstances have an indirect influence upon that quantity, and particularly the degree of skill possessed by the spinner. The better the machine, the steadier and softer all its parts revolve, the better and more abundant is its production. When the toothed wheels do not work truly into their pinions, when the spindles shake in their bushes, or are not accurately made, many threads break, and the work is much injured and retarded. The better the staple of the cotton wool, and the more careful has been its preparation in the carding, drawing, and roving processes, the more easy and excellent the spinning will become: warmth, dryness, cold, and moisture have great influence on the ductility, so to speak, of cotton. A temperature of 65° F., with an atmosphere not too arid, is found most suitable to the operations of a spinning mill. The finer the yarn, the slower is the spinning. For numbers from 20 to 36, from 2 to 3 stretches of warp may be made in a minute, and nearly 3 stretches of weft; for numbers above 50 up to 100, about 2 stretches; and for numbers from 100 to 150, one stretch in the minute. Still finer yarns are spun more slowly, which is not wonderful, since in the fine spinning mills of England, the mules usually contain upwards of 500 spindles each, in order that one operative may manage a great number of them, and thereby earn such high wages as shall fully remunerate his assiduity and skill.In spinning fine numbers, the second speed is given before the carriage is run out to the end of its railway; during which course of about six inches, it is made to move very slowly. This is called the second stretch, and is of use in making the yarn level by drawing down the thicker parts of it, which take on the twist less readily than the thinner, and therefore remain softer and more extensible. The stretch may therefore be divided into three stages. The carriage first moves steadily out for about 4 feet, while the drawing rollers and spindles are in full play; now the rollers stop, but the spindles go on whirling with accelerated speed, and the carriage advances slowly, about 6 inches more; then it also comes to rest, while the spindles continue to revolve for a little longer, to give the final degree of twist. The acceleration of the spindles in the second and third stages, which has no other object but to save time, is effected by a mechanism called thecounter, which shifts the driving band, at the proper time, upon the loose pulley, and, moreover, a second band, which had, till now, lain upon its loose pulley, upon a small driving pulley of the rim-shaft. At length, both bands are shifted upon their loose pulleys, and the mule comes to a state of quiescence.TheSELF-ACTOR MULE, or theIRON MAN, as it has been called in Lancashire, is an invention to which the combinations among the operative spinners obliged the masters to have recourse. It now spins good yarn up to 40 s with great uniformity and promptitude, and requires only juvenile hands to conduct it, to piece the broken yarns, to replace the bobbins of rovings in the creel, and to remove the finished cops from the spindles.The self-acting mules were first constructed, I believe, by Messrs. Eaton, formerly of Manchester, who mounted ten or twelve of them in that town, four at Wiln, in Derbyshire, and a few in France. From their great complexity and small productiveness, the whole were soon relinquished, except those at Wiln. M. de Jong obtained two patents for self-acting mules, and put twelve of them in operation in a mill at Warrington, of which he was part proprietor; but with an unsuccessful result. I saw thedébrisof one of M. de Jong’s self-actors in the factory of M. Nicolas Schlumberger, at Guebwiller, in Alsace, where the machine had been worked for three months, without advantage, under the care of the inventor, who is a native of that valley.The first approximation to a successful accomplishment of the objects in view, was an invention of a self-acting mule, by Mr. Roberts, of Manchester; one of the principal points of which was the mode of governing the winding-on of the yarn into the form of a cop; the entire novelty and great ingenuity of which invention was universally admitted, and proved the main step to the final accomplishment of what had so long been a desideratum. For that invention a patent was obtained in 1825, and several headstocks upon the principle were made, which are still working successfully.In 1830, Mr. Roberts obtained a patent for the invention of certain improvements; and by a combination of both his inventions, he produced a self-acting mule, which is generally admitted to have exceeded the most sanguine expectations, and which has been extensively adopted. There are, probably, at present, upwards of half a million of spindles of Messrs. Sharp, Roberts, and Co.’s construction, at work in the United Kingdom, and giving great satisfaction to their possessors. The advantages of these self-actors are the following:—The saving of a spinner’s wages to each pair of mules, piecers only being required, as one overlooker is sufficient to manage six or eight pairs of mules. The production of a greater quantity of yarn, in the ratio of from 15 to 20 per cent. The yarn possesses a more uniform degree of twist, and is not liable to be strained during the spinning, or in winding-on, to form the cop; consequently fewer threads are broken in these processes, and the yarn, from having fewer piecings is more regular.The cops are made firmer, of better shape, and with undeviating uniformity; and, from being more regularly and firmly wound, contain from one third to one half more yarn than cops of equal bulk wound by hand; they are consequently less liable to injury in packing or in carriage, and the expense of packages and freight (when charged by measurement) is considerably reduced.From the cops being more regularly and firmly wound, combined with their superior formation, the yarn intended for warps less frequently breaks in winding or reeling, consequently there is a considerable saving of waste in those processes.Secondly, the advantages connected with weaving.The cops being more regularly and firmly wound, the yarn, when used as weft, seldom breaks in weaving; and as the cops also contain a greater quantity of weft, there are fewer bottoms, consequently there is a very material saving of waste in the process of weaving.From those combined circumstances, the quality of the cloth is improved, by being more free from defects caused by the breakage of the warp or weft, as well as the selvages being more regular.The looms can also be worked at greater speed; and, from there being fewer stoppages, a greater quantity of cloth may be produced.That the advantages thus enumerated, as derivable from the use of self-acting mules, have not been overrated, but, in many instances, have been considerably exceeded, I have, by extensive personal inquiry and observation, had ample opportunity of ascertaining.Statement of the quantity of yarn produced on Messrs. Sharp, Roberts, and Co.’s self-acting mules, in twelve working hours, including the usual stoppages connected with spinning, estimated on the average of upwards of twenty mills:—No. of Yarn.No. of Twist.No. of Weft.1641⁄2hanks47⁄8hanks per spindle.2441⁄4—45⁄8—324—43⁄8—4033⁄4—41⁄8—Of the intermediate numbers the quantities are proportionate.Results of trials made by Messrs. Sharp, Roberts, and Co., at various mills, to ascertain the comparative power required to work self-acting mules, in reference to hand-mules, during the spinning, up to the period of backing off.Particulars of the trials referred to, and their results:—At what Mill, and theDescription of Mule.No.and kindof Yarn.DiameterofPulleyorRimWheel.Revo-lutionsofPulleyorRimWheel.Re-quiredForceforMotion.TotalForceEmployedinSpinning.Messrs. Birley and Kirk.Weft.Ins.lbs.lbs.Self-acting mule, 360 sps.30 to 341258305463[20]Hand mule, 180 sps.ditto1536263669-× 2 =7338Messrs. Leech and Vandrey.Twist.[21]Self-acting mule, 324 sps.361270367912Hand mules, 324 sps.362958161⁄27273Messrs. Duckworth & Co.Twist.Self-acting mule, 324 sps.401262336421Hand mule, 324 sps.404736151⁄26646
Fly frame
This cylindrical box pulley is made in two parts,kandl, and slipped upon the axle with a toothed wheelm, intervening between them. The box and wheel are shewn detached infig.343., and partly in section atfig.344.That portion of the box with its pulley markedl, is fixed to the shaftg; but the other part of the box and its pulleyk, and the toothed wheelm, slide loosely round upon the shaftg, and when brought in contact and confined by a fixed collarn, as in the machine shewn atfig.342., they constitute two distinct pullies, one being intended to actuate the spindles, and the other the bobbins.
In the web of the wheelm, a small bevel piniono, is mounted upon an axle standing at right angles to the shaftg, which pinion is intended to take into the two bevel pinionspandq, respectively fixed upon bosses, embracing the shaft in the interior of the boxeskandl. Now it being remembered that the pinionq, and its boxl, are fixed to the shaftg, and turn with it, if the loose wheelmbe independently turned upon the shaft, with a different velocity, its piniono, taking intoq, will be made to revolve upon its axle, and to drive the pinionp, and pulley boxk, in the same direction as the wheelm; and this rotatory movement of the boxkand wheelm, may be faster or slower than the shaftg, and boxl, according to the velocity with which the wheelmis turned.
Having explained the construction of the box pullieskandl, 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 shaftg, being turned by the band and riggerA, as above said, the train of wheelsh, connected with it, drives the shafti, which at its reverse end has a pinion (not seen in the figure,) that actuates the whole series of drawing rollersa. Upon the shaftithere is a sliding pulleyr, carrying a bands, which passes down to a tension pulleyt, and is kept distended by a weight. This bands, in its descent, comes in contact with the surface of the coneu, and causes the cone to revolve by the friction of the band running against it. The pulleyris progressively slidden along the shafti, 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 progressively shifting the bandsfrom 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 coneua small pinionvis fixed, which takes into the teeth of the loose wheelm, and, as the cone turns, drives the wheelmround upon the shaftg, with a speed dependent always upon the rapidity of the rotation of the cone. Now the box pulleyl, being fixed to the main shaftg, turns with one uniform speed, and by cords passing from it over guides to the whorlsf, drives all the spindles and flyers, which twist the yarns with one continued uniform velocity; but the box pulleyk,being loose upon the shaft, and actuated by the bevel pinions within, as described, is made to revolve by the rotation of the wheelm, independent of the shaft, and with a different speed from the pulley boxl; cords passing from this pulley boxk, over guides to small pullies under the bobbins, communicate the motion, whatever it may be, of the pulley boxk, 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 pinionv, for one with a different number of teeth, which will cause the wheelm, and the pulley boxk, 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 less tenuity, made on the bobbin and fly, or tube roving frame, are either spun immediately into firm cohesive yarn, or receive a further preparation process 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.
Thefinishing machinesof a cotton mill, which spin the cohesive yarn, are of two classes; 1. the water-twist or throstle, in which the twisting and winding are performed simultaneously upon progressive 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.
Throstle
The water-twist frame, so called by its inventor, Sir R. Arkwright, 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 essentially 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, possessing 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 creela 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 fineness, upon the principles already explained. At its escape from the front rollers, every thread runs through a guide eyeleteof wire, which gives it the vertical direction down towards the spindlesf,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 atgin steps, pass atvthrough a brass bush or collet which keeps them upright, and revolve with remarkable speed upon their axes. The bobbinsh, 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 beaml, 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 atfis tubular, to allow the thread to pass 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 eyeleti, it proceeds directly to the bobbin. By the twirling of the spindle, the twisting of the portion of thread between the front rollerd, and the nozzlef, 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 motionless, 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 rollerd, 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 rollersd, deliver, for example, one inch of yarn. The inertia or weight of the bobbin, and its friction upon the copping beaml, 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 flyi, 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 process in spinning is essentially 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 employmentof this tension is impossible, because the roving has too little cohesion to bear the strain; and hence it is necessary 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 raill, is made fast to a barm, and this, which slides in a vertical groove or slot at the end of the frame, is connected by a rodn, with an equal-armed, moveable levero. The rodpcarries a weightr, suspended from this lever; another rodq, connects the great leverowith a smaller ones,t, upon which a heart-shaped disc or pulleyu, works from below att. By the rotation of the discu, the armt, being pressed constantly down upon it by the reaction, the weightrmust alternately rise and fall; and thus the copping raillmust obviously move with the bobbinshup 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 smallness 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 successively 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 endless bandsx x. Each spindle is mounted with a small pulley or wharfw, at its lower part, and a particular band, which goes round that wharf or whorl, and the drumy. 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 pressure 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 : 11⁄2: 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 41⁄2, 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 71⁄2times, whence the number of the yarn would come out 32 = 71⁄2× 41⁄2. 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 pulleyu,fig.345.
The driving pulley makes about 600 turns in a minute; and as the diameter of the drumy,fig.345., is six times the diameter of the spindle wharvesw, 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 less twist goes into a given length of yarn. If, for example, the front rollersd, 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 offig.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 pressed by its top rollers with a weight of ten ortwelve 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 pressure in one line.
For the service of 240 spindles, in two double frames, one young woman, and an assistant 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 30′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 Danforth’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.
Mule-spinning.—The general principles of the mule have been already stated. This machine is so named because it is the offspring, so to speak, of two older machines, the jenny and the water-frame. A mule is mounted with from 240 to 1000 spindles, and spins of course as many threads.
Hargreaves's jenny
Fig.346.represents the originaljennyof Hargreaves, by which one person was enabled to spin from 16 to 40 threads at once. The soft cords of rovings wound in double conical cops upon skewers were placed in the inclined frame atC; the spindles for first twisting and then winding-on the spun yarn were set upright in steps and bushes atA, being furnished near their lower ends with whorls, and endless cords, which were driven by passing round the long-revolving drum of tin plateE.Dis the clasp or clove, having a handle for lifting its upper jaw a little way, in order to allow a few inches of the soft roving to be introduced. The compound cloveDbeing now pushed forward upon its friction wheels toA, was next gradually drawn backward, while the spindles were made to revolve with proper speed by the right hand of the operative turning the flywheelB. Whenever onestretchwas thereby spun, the clove frame was slid home towardsA; the spindles being simultaneously whirled slowly to take up the yarn, which was laid on in a conical cop by the due depression of the faller wire atAwith the spinner’s left hand.
Arkwright's water frame
Fig.347.is a diagram of Arkwright’s originalwater-framespinning machine, called afterwards thewater-twistframe. The rovings mounted upon bobbins in the creelA A, have their ends led through between the three sets of twin rollers belowB B, thence down through the eyelet hooks upon the end of the flyers of the spindlesC, and finally attached to their bobbins. The spindles being driven by the bandD Dupon their lower part, continuously twist and wind the finished yarn upon the bobbins; constituting the first unremitting automatic machine for spinning which the world ever saw.
Hindostan spinster
Contrast with the above admirable system, the primitive cotton wheel of India, as represented in the annexedfigure 348. By the aid of mechanical fingers, one Englishman at his mule can turn off daily more yarn and of far finer quality than 200 of the most diligent spinsters of Hindostan.
MuleFig. 349 enlarged(195 kB)
Fig. 349 enlarged(195 kB)
Fig.349., is a transverse section of the mule, in which its principal parts are shown.
The machine consists of two main parts; a fixed one corresponding in some measure to the water-frame or throstle, and a moveable one corresponding to the jenny. The first contains in a suitable frame the drawing roller-beam and the chief moving machinery: the second, is called the carriage, in which the remainder of the moving mechanism and the spindles are mounted.
The frame of the fixed part consists of two upright sides, and two or more intermediate parallel bearings, upon which the horizontal roller beama, the basis of the drawing rollers is supported,b,c,d, are the three ranges of fluted iron rollers;e,f,g, are the upper iron rollers covered with leather;h, the wooden wiper-rollers covered with flannel, which being occasionally rubbed with chalk, imparts some of it to the pressure rollers beneath, so as to prevent the cotton filaments adhering to them. The rollers are made throughoutthe whole length of the mule in portions containing six flutings, which are coupled together by squared ends fitted into square holes.
The skewers upon which the bobbins containing the rovings from the bobbin and fly or stretching frame, are set up, are seen ata1,a1,a1, arranged in three rows in the creelz. The soft threads unwound from these bobbins, in their way to the drawing rollers, pass first through eyelets in the ends of the wire armsb1, then through the rings or eyes of the guide barw, and enter between the back pair of rollers. The number of these bobbins is equal to the number of spindles in the mule, and twice as great as the number of fluted portions of the rollers; for two threads are assigned to each portion.
The carriage consists of two cast-iron side pieces, and several cast-iron intermediate similar pieces, such asf2, which all together are made fast to the planksb2,c2,d2. The top is covered in with the plankk2. The carriage runs by means of its cast-iron grooved wheels, upon the cast-iron railwayl2, which is fixed level on the floor.
The spindles stand upon the carriage in a frame, which consists of two slant railsx2,x2, connected by two slender rodsy2, and which frame may be set more or less obliquely. The lower rail carries the brass steps for the points of the spindlesb3; upon the upper rail brass slips are fixed pierced with holes through which the tops of the spindles play. The spindles are as usual made of steel, perfectly straight, turned truly round, and are all arranged in one plane. To each of them a small wooden or cast-iron whorlg2is made fast. They are distributed into groups of 24, and the whorls are arranged at such different heights, that only two of them in each group are upon a level with each other. A small brass headh2, which every spindle has beneath the upper slant rail of the framex2, prevents their sitting down into the step, during their rotation, or sliding off their cop of yarn.
c3are drums, mounted in the carriage in a plane at right angles to the plane in which the spindles are placed. At top they have a double groove for a cord to run in, and the motion which they receive from the great fly wheel, or rim of the mule (not visible in this view) they impart to the spindles. Such a drum is assigned to every 24 spindles; and therefore a mule of 480 spindles contains 20 drums. In the middle of the carriage is seen the horizontal pulleyk3, furnished with three grooves, which stands in a line with the drumsc3.
The motion is given to the drumsc3, upon the right hand half of the carriage by a single endless band or cord which proceeds from the middle groove of the pulleyk3. The rotation of the spindles is produced by a slender cord, of which there are 12 upon each drumc3; because every such cord goes round the drum, and also every two wharves which stand at the same level upon the spindles. It is obvious that the drums, and consequently the spindles, must continue to revolve as long as the main rim of the mule is turned, whether the carriage be at rest or in motion upon its railway.
If we suppose the carriage to be run in to its standing point, or to be pushed home to the spot from which it starts in spinning, its back plankd2will strike the postq3upon the fixed frame, and the points of the spindles will be close in front of the roller beam. The rollers now begin to turn and to deliver threads, which receive immediately a portion of their twist from the spindles; the carriage retires from the roller beam with somewhat greater speed than the surface speed of the front rollers, whereby the threads receive a certain degree of stretching, which affects most their thicker and less twisted portions, and thereby contributes greatly to the levelness of the yarn. When the carriage has run out to the end of its course, or has completed a stretch, the fluted rollers suddenly cease to revolve (and sometimes even beforehand, when a second stretch is to be made), but the spindles continue to whirl till the fully extended threads have received the proper seconder after-twist. Then the carriage must be put up, or run back towards the rollers, and the threads must be wound upon the spindles.
This is the order of movements which belong to the mule. It has been shown how the rotation of the spindles is produced.
For winding-on the yarn the carriage has a peculiar apparatus, which we shall now describe. In front of it, through the whole extent to the right hand as well as the left, a slender iron rod,d5, runs horizontally along, in a line somewhat higher than the middle of the copping portion of the spindles, and is supported by several props, such ase5. Upon each end of the two rods,d5, there is an arm,g5; and betwixt these arms an iron wire, called the copping wire,f5, is stretched, parallel with the rodd5. For the support of this wire, there are several slender bent armsh5extended from the rodd5at several points betwixt the straight armsg5. The rodd5has, besides a wooden handle at the place opposite to where the spinner stands, by which it can be readily grasped. This movement is applied at the left division of the machine, and it is communicated to the right by an apparatus which resembles a crane’s bill. The two arms,g5, in the middle of the machine, project over the rodsd5, and are connected by hinges with two vertical rodsj5, which hang together downwards in like manner with two armsi5, proceeding from a horizontal axisk5.
By means of that apparatus the yarn is wound upon the spindles in the following manner. As long as the stretching and twisting go on, the threads form an obtuse angle with the spindles, and thereby slide continually over their smooth rounded tips during their revolution, without the possibility of coiling upon them. When, however, the spinning process is completed, the spinner seizes the carriage with his left hand and pushes it back towards the roller beam, while with his right hand he turns round the handle of the rim or fly wheel, and consequently the spindles. At the same time, by means of the handle upon the rodd5, he moves the copping-wire,f5, so that it presses down all the threads at once, and places them in a direction nearly perpendicular to the spindles; as shown by the dotted liney5. That this movement of the copping wire, however, may take place without injury to the yarn, it is necessary to turn the rim beforehand a little in the opposite direction, so that the threads may get uncoiled from the upper part of the spindles, and become slack; an operation called in technical language, thebacking off. The range upon which the threads should be wound, in order to form a conical cop upon the spindle, is hit by depressing the copping wire to various angles, nicely graduated by an experienced eye. This faller wire alone is not, however, sufficient for the purpose of winding-on a seemly cop, as there are always some loose threads which it cannot reach without breaking others.
Another wire called thecounter-faller,l5, must be applied under the threads. It may be raised to an elevation limited by the angular piecep5; and is counterpoised by a very light weightm5, applied through the bent levern5, which turns upon the fulcrumo5. This wire, which applies but a gentle pressure, gives tension to all the threads, and brings them regularly into the height and range of the fallerf5. This wire must be raised once more, whenever the carriage approaches the roller beam. At this instant a new stretch commences; the rollers begin again to revolve, and the carriage resumes its former course. These motions are performed by the automatic machinery.
There is a little eccentric pulley mechanism for moving the guide beam to and fro with the soft yarns, as they enter between the back rollers. On the right hand end of the back roller shaft, a worm screw is formed which works into the oblique teeth of a pinion attached to the end of the guide beam, in which there is a series of holes for the passage of the threads, two threads being assigned to each fluted roller. In the flat disc of the pinion, an eccentric pin stands up which takes into the jointed lever upon the end of the guide beam, and as it revolves, pushes that beam alternately to the left and the right by a space equal to its eccentricity. This motion is exceedingly slow, since for each revolution of the back roller, the pinion advances only by one tooth out of the 33 which are cut in its circumference.
After counting the number of teeth in the different wheels and pinions of the mule, or measuring their relative diameters, it is easy to compute the extension and twist of the yarns; and when the last fineness is given to ascertain their marketable value. Let the ratio of speed between the three drawing rollers be 1 : 13⁄22: 71⁄2; and the diameter of the back and middle roller three quarters of an inch: that of the front roller one inch; in which case the drawing is thereby increased 11⁄3times, and 71⁄2× 11⁄3= 10. If the rovings in the creel bobbins have been No. 4. the yarn, after passing through the rollers, will be No. 40. By altering the change pinion (not visible in this view) the fineness may be changed within certain limits, by altering the relative speed of the rollers. For one revolution of the great rim or fly wheel of the mule, the front roller makes about 6-tenths of a turn, and delivers therefore 22·6 lines or 12ths of an inch of yarn, which, in consequence of the tenfold draught through the rollers, corresponds to 2·26 lines of roving fed in at the back rollers. The spindles or their whorls make about 66 revolutions for one turn of the rim. The pulleys or grooved wheels on which the carriage runs, perform 0·107 part of a turn while the rim makes one revolution, and move the carriage 24·1 lines upon its rails, the wheels being 6 inches in diameter.
The 22·6 lines of soft yarn delivered by the front rollers, will be stretched 11⁄2lines by the carriage advancing 24·1 lines in the same time. Let the length of the railway, or of each stretch be 5 feet, the carriage will complete its course after 30 revolutions of the rim wheel, and the 5 feet length of yarn (of which 561⁄2inches issue from the drawing rollers, and 31⁄2inches proceed from the stretching) is, by the simultaneous whirling of the spindles, twisted 1980 times, being at the rate of 33 twists for every inch. The second twist, which the threads receive after the carriage has come to repose, is regulated according to the quality of the cotton wool, and the purpose for which the yarn is spun. For warp yarn of No. 40 or 50, for example, 6 or 8 turns of the rim wheel, that is, from 396 to 528 whirls of the spindles for the whole stretch, therefore from 7 to 9 twists per inch will be sufficient. The finished yarn thus receives from 40 to 42 twists per inch.
One spinner attends to two mules, which face each other, so that he needs merely turn round in the spot where he stands, to find himself in the proper position for the other mule. For this reason the rim wheel and handle, by which he operates, are notplaced in the middle of the length of the machine, but about two fifths of the spindles are to the right hand and three fifths to the left; the rim wheel being towards his right hand. The carriage of the one mule is in the act of going out and spinning, while that of the other is finishing its twist, and being put up by the spinner.
The quantity of yarn manufactured by a mule in a given time, depends directly upon the number of the spindles, and upon the time taken to complete every stretch of the carriage. Many circumstances have an indirect influence upon that quantity, and particularly the degree of skill possessed by the spinner. The better the machine, the steadier and softer all its parts revolve, the better and more abundant is its production. When the toothed wheels do not work truly into their pinions, when the spindles shake in their bushes, or are not accurately made, many threads break, and the work is much injured and retarded. The better the staple of the cotton wool, and the more careful has been its preparation in the carding, drawing, and roving processes, the more easy and excellent the spinning will become: warmth, dryness, cold, and moisture have great influence on the ductility, so to speak, of cotton. A temperature of 65° F., with an atmosphere not too arid, is found most suitable to the operations of a spinning mill. The finer the yarn, the slower is the spinning. For numbers from 20 to 36, from 2 to 3 stretches of warp may be made in a minute, and nearly 3 stretches of weft; for numbers above 50 up to 100, about 2 stretches; and for numbers from 100 to 150, one stretch in the minute. Still finer yarns are spun more slowly, which is not wonderful, since in the fine spinning mills of England, the mules usually contain upwards of 500 spindles each, in order that one operative may manage a great number of them, and thereby earn such high wages as shall fully remunerate his assiduity and skill.
In spinning fine numbers, the second speed is given before the carriage is run out to the end of its railway; during which course of about six inches, it is made to move very slowly. This is called the second stretch, and is of use in making the yarn level by drawing down the thicker parts of it, which take on the twist less readily than the thinner, and therefore remain softer and more extensible. The stretch may therefore be divided into three stages. The carriage first moves steadily out for about 4 feet, while the drawing rollers and spindles are in full play; now the rollers stop, but the spindles go on whirling with accelerated speed, and the carriage advances slowly, about 6 inches more; then it also comes to rest, while the spindles continue to revolve for a little longer, to give the final degree of twist. The acceleration of the spindles in the second and third stages, which has no other object but to save time, is effected by a mechanism called thecounter, which shifts the driving band, at the proper time, upon the loose pulley, and, moreover, a second band, which had, till now, lain upon its loose pulley, upon a small driving pulley of the rim-shaft. At length, both bands are shifted upon their loose pulleys, and the mule comes to a state of quiescence.
TheSELF-ACTOR MULE, or theIRON MAN, as it has been called in Lancashire, is an invention to which the combinations among the operative spinners obliged the masters to have recourse. It now spins good yarn up to 40 s with great uniformity and promptitude, and requires only juvenile hands to conduct it, to piece the broken yarns, to replace the bobbins of rovings in the creel, and to remove the finished cops from the spindles.
The self-acting mules were first constructed, I believe, by Messrs. Eaton, formerly of Manchester, who mounted ten or twelve of them in that town, four at Wiln, in Derbyshire, and a few in France. From their great complexity and small productiveness, the whole were soon relinquished, except those at Wiln. M. de Jong obtained two patents for self-acting mules, and put twelve of them in operation in a mill at Warrington, of which he was part proprietor; but with an unsuccessful result. I saw thedébrisof one of M. de Jong’s self-actors in the factory of M. Nicolas Schlumberger, at Guebwiller, in Alsace, where the machine had been worked for three months, without advantage, under the care of the inventor, who is a native of that valley.
The first approximation to a successful accomplishment of the objects in view, was an invention of a self-acting mule, by Mr. Roberts, of Manchester; one of the principal points of which was the mode of governing the winding-on of the yarn into the form of a cop; the entire novelty and great ingenuity of which invention was universally admitted, and proved the main step to the final accomplishment of what had so long been a desideratum. For that invention a patent was obtained in 1825, and several headstocks upon the principle were made, which are still working successfully.
In 1830, Mr. Roberts obtained a patent for the invention of certain improvements; and by a combination of both his inventions, he produced a self-acting mule, which is generally admitted to have exceeded the most sanguine expectations, and which has been extensively adopted. There are, probably, at present, upwards of half a million of spindles of Messrs. Sharp, Roberts, and Co.’s construction, at work in the United Kingdom, and giving great satisfaction to their possessors. The advantages of these self-actors are the following:—
The saving of a spinner’s wages to each pair of mules, piecers only being required, as one overlooker is sufficient to manage six or eight pairs of mules. The production of a greater quantity of yarn, in the ratio of from 15 to 20 per cent. The yarn possesses a more uniform degree of twist, and is not liable to be strained during the spinning, or in winding-on, to form the cop; consequently fewer threads are broken in these processes, and the yarn, from having fewer piecings is more regular.
The cops are made firmer, of better shape, and with undeviating uniformity; and, from being more regularly and firmly wound, contain from one third to one half more yarn than cops of equal bulk wound by hand; they are consequently less liable to injury in packing or in carriage, and the expense of packages and freight (when charged by measurement) is considerably reduced.
From the cops being more regularly and firmly wound, combined with their superior formation, the yarn intended for warps less frequently breaks in winding or reeling, consequently there is a considerable saving of waste in those processes.
Secondly, the advantages connected with weaving.
The cops being more regularly and firmly wound, the yarn, when used as weft, seldom breaks in weaving; and as the cops also contain a greater quantity of weft, there are fewer bottoms, consequently there is a very material saving of waste in the process of weaving.
From those combined circumstances, the quality of the cloth is improved, by being more free from defects caused by the breakage of the warp or weft, as well as the selvages being more regular.
The looms can also be worked at greater speed; and, from there being fewer stoppages, a greater quantity of cloth may be produced.
That the advantages thus enumerated, as derivable from the use of self-acting mules, have not been overrated, but, in many instances, have been considerably exceeded, I have, by extensive personal inquiry and observation, had ample opportunity of ascertaining.
Statement of the quantity of yarn produced on Messrs. Sharp, Roberts, and Co.’s self-acting mules, in twelve working hours, including the usual stoppages connected with spinning, estimated on the average of upwards of twenty mills:—
Of the intermediate numbers the quantities are proportionate.
Results of trials made by Messrs. Sharp, Roberts, and Co., at various mills, to ascertain the comparative power required to work self-acting mules, in reference to hand-mules, during the spinning, up to the period of backing off.
Particulars of the trials referred to, and their results:—