The Bobbin and Fly frame

is now the great roving machine of the cotton manufacture; to which may be added, for coarse spinning, the tube roving frame. Of such a complicated machine as the bobbin and fly frame, it is not po ible to give an adequately detailed description in the space due to the subject in this Dictionary. Its mechanical combinations are however so admirable as to require such an account as will make its functions intelligible by the general reader. IMG:4147767755307473660_illo0355a.png:Bobbin and fly frame Fig. 332 enlarged (367 kB) Fig. 332. exhibits a back view of this machine; and fig. 333. a section of some of the parts not very visible in the former figure. The back of the machine is the side at which the cotton is introduced between the drawing rollers. IMG:4147767755307473660_illo0355b.png:Detail of machine The cans, or lap-bobbins filled with slivers at the drawing frame, are placed in the situation marked B , fig. 333. , in rows parallel with the length of the machine. The sliver of each can or the united slivers of two contiguous cans are conducted upwards along the surface of a sloping board f , and through an iron staple or guide e , betwixt the usual triple pair of drawing rollers, the first of which is indicated by a , b . In fig. 332. , for the purpose of simplifying the figure, the greater part of these rollers and their subordinate parts are omitted. After the slivers have been sufficiently extended and attenuated between the rollers, they proceed forwards, towards the spindles i i i , where they receive the twist, and are wound upon the bobbins h . The machine delineated contains thirty spindles, but many bobbin and fly frames contain double or even four times that number. Only a few of the spindles are shown in fig. 332. , for fear of confusing the drawing. IMG:4147767755307473660_illo0356a.png:Fluted rollers With regard to the drawing functions of this machine, I have already given abundant explanation, so far as the properties and operation of the rollers are concerned. The frame-work of this part of the machine, called the roller-beam , is a cast iron bench, upon which nine bearers c , are mounted for carrying the rollers. The fluted rollers a a a , fig. 334. , are constructed in four pieces for the whole length, which are parted from each other by thinner smooth cylindric portions z , called necks. Seven such partings for four rollers, and one parting for two rollers, constitute together the 30 fluted rollers of which the whole series consists. The coupling of these roller subdivisions into one cylinder, is secured by the square holes x , and square pins y , fig. 334. , which fit into the holes of the adjoining subdivision. The top or pre ure rollers b , are two-fold over the whole set; and the weighted saddle pre es upon the neck w , which connects every pair, as was already explained under fig. 329. These weights g , g , fig. 333. , are applied in this as in the drawing frame ; d , are the bars faced with flannel for cleaning the top rollers. A similar bar is applied beneath the rollers, to keep the flutings clean. IMG:4147767755307473660_illo0356b.png:Spindle The structure and operation of the spindles i , may be best understood by examining the section fig. 335. They are made of iron, are cylindrical from the top down to a 2 , but from this part down to the steel tipt rounded points they are conical. Upon this conical portion there is a pulley k , furnished with two grooves in its circumference, in which the cord runs that causes the spindle to revolve. The wooden bobbin h , is slid upon the cylindrical part, which must move freely upon it, as will be presently explained. To the bobbin another two-grooved pulley or whorl q is made fast by means of a pin r , which pa es through it; by removing this pin, the bobbin can be instantly taken off the spindle. The upper end of the spindle bears a fork s t , which may be taken off at pleasure by means of its left-handed screw; this fork or flyer, has a funnel-formed hole at v . One arm of the fork is a tube s , u , open at top and bottom; the leg t , is added merely as a counterpoise to the other. In fig. 333. , for the sake of clearne , the forks or flyers of the two spindles here represented are left out; and in fig. 332. only one is portrayed for the same reason. It is likewise manifest from a comparison of these two figures that the spindles are alternately placed in two rows, so that each spindle of the back range stands opposite the interval between two in the front range. The object of this distribution is economy of space, as the machine would need to be greatly longer if the spindles stood all in one line. If we suppose the spindles and the bobbins (both of which have independent motions) to revolve simultaneously and in the same direction, their operation will be as follows: The sliver properly drawn by the fluted rollers, enters the opening of the funnel v , proceeds thence downwards through the hole in the arm of the fork, runs along its tube u , s , and then winds round the bobbin. This path is marked in fig. 335. by a dotted line. The revolution of the spindles in the above circumstances effects the twisting of the sliver into a soft cord; and the flyer s , t , or particularly its tubular arm s , lays this cord upon the bobbin. Were the speed of the bobbins equal to that of the spindles, that is, did the bobbin and spindle make the same number of turns in the same time, the proce would be limited to mere twisting. But the bobbin anticipates the flyers a little, that is, it makes in a given time a somewhat greater number of revolutions than the spindle, and thereby effects the continuous winding of the cord upon itself. Suppose the bobbin to make 40 revolutions, while the spindle completes only 30; 30 of these revolutions of the bobbin will be inoperative towards the winding-on, because the flyers follow at that rate, so that the cord or twisted sliver will only be coiled 10 times round the bobbin, and the result as to the winding-on will be the same as if the spindle had stood still, and the bobbin had made 40 - 30 = 10 turns. The 30 turns of the spindles serve, therefore, merely the purpose of communicating twist. The mounting and operation of the spindles are obviously the same as they are upon the household flax wheel. In the bobbin and fly frame there are some circumstances which render the construction and the winding-on somewhat difficult, and the mechanism not a little complicated. It may be remarked in the first place, that as the cord is wound on, the diameter of the bobbin increases very rapidly, and therefore every turn made round it causes a greater length of roving to be taken up in succe ion. Were the motions of the bobbins to continue unchanged in this predicament, the increased velocity of the winding-on would require an increased degree of extension, or it would occasion the rupture of the cord, because the front fluted rollers move with uniform speed, and therefore deliver always the same length of sliver in the same time. It is therefore nece ary to diminish the velocity of the bobbins, or the number of their turns, in the same proportion as their diameter increases, in order that the primary velocity may remain unchanged. Moreover, it is requisite for the proper distribution of the cord upon the bobbin, and the regular increase of its diameter, that two of its succe ive convolutions should not be applied over each other, but that they should be laid close side by side. This object is attained by the up and down sliding motion of the bobbin upon the spindle, to the same extent as the length of the bobbin barrel. This up and down motion must become progre ively slower, since it increases the diameter of the bobbin at each range, by a quantity equal to the diameter of the sliver. What has now been stated generally, will become more intelligible by an example. Let it be a umed that the drawing rollers deliver, in 10 seconds, 45 inches of roving, and that this length receives 30 twists. The spindles must, in consequence, make 30 revolutions in 10 seconds, and the bobbins must turn with such speed, that they wind up the 45 inches in 10 seconds. The diameter of the bobbin barrels being 1 1 ⁄ 2 inches, their circumference of course 4 1 ⁄ 2 inches, they must make 10 revolutions more in the same time than the spindles. The effective speed of the bobbins will be thus 30 + 10 = 40 turns in 10 seconds. Should the bobbins increase to 3 inches diameter, by the winding-on of the sliver, they will take up 9 inches at each turn, and consequently 45 inches in 5 turns. Their speed should therefore be reduced to 30 + 5 = 35 turns in 10 seconds. In general, the exce in number of revolutions, which the bobbins must make over the spindles, is inversely as the diameter of the bobbins. The speed of the bobbins must remain uniform during the period of one ascent or descent upon the spindle, and must diminish at the instant of changing the direction of their up and down motion; because a fresh range of convolutions then begins with a greater diameter. When, for example, 30 coils of the sliver or roove are laid in one length of the bobbin barrel, the bobbin must complete its vertical movement up or down, within 30 seconds in the first case above mentioned, and within 60 seconds in the second case. The motions of the drawing rollers, the spindles, and bobbins, are produced in the following manner:—A shaft c′ , fig. 332. and 333. , extending the whole length of the machine, and mounted with a fly wheel d′ , is set in motion by a band from the running pulley upon the shaft of the mill, which actuates the pulley a′ . b′ is the loose pulley upon which the band is shifted when the machine is set at rest. Within the pulley a′ , but on the outside of the frame, the shaft c′ carries a toothed wheel b 2 with 50 teeth, which by means of the intermediate wheel c 2 turns the wheel d 2 upon the prolonged shaft of the backmost fluted roller ( m 2 , fig. 333. ) This wheel d 2 has usually 54 teeth; but it may be changed when the roove is to receive more or le twist; for as the spindles revolve with uniform velocity, they communicate the more torsion the le length of sliver is delivered by the rollers in a given time. Upon the same shaft with d 2 , a pinion e 2 of 32 teeth is fixed, which works in a wheel f 2 of 72 teeth. Within the frame a change pinion g 2 is made fast to the shaft of f 2 . This pinion, which has usually from 24 to 28 teeth, regulates the drawing, and thereby the finene or number of the roving. It works in a 48-toothed wheel h 2 upon the end of the backmost fluted roller a , fig. 333. The other extremity of the same roller, or, properly speaking, line of rollers, carries a pinion l 2 , furnished with 26 teeth, which, by means of the broad intermediate wheel k 2 , sets in motion the pinion i′ 2 of 22 teeth upon the middle roller. When the diameter of all the drawing rollers is the same, suppose 1 inch, their proportional velocities will be, with the above number of teeth in the wheel work, if g 2 have 24 teeth, as 1: 1·18: 4·5; and the drawn sliver will have 4 1 ⁄ 2 times its original length. The front or delivery roller of the drawing frame is of late years usually made 1 1 ⁄ 4 or 1 3 ⁄ 8 inches in diameter. If 625 feet of the sliver from the drawing frame weighed one pound, 2790 feet of the roving will now go to this weight, and the number will be 1·12; that is, 1 hank and 12 hundredths to the pound. The front pair of fluted rollers makes about 90 revolutions, and delivers 282·6 inches of roving in the minute, when of one inch diameter. The spindles i , ( fig. 332. and 333. ), rest, with their lower ends, in steps l , which are fixed in an immoveable beam or bar m . To protect it from dust and cotton filaments, this beam is furnished with a wooden cover n , in which there are small holes for the pa age of the spindles right over the steps. In fig. 332. , two of the eight covers n , which compose the whole range m , are removed to let the steps be seen. The cylindrical part of each spindle pa es through a bra ring o ; and all these 30 rings, whose centres must be vertically over the steps l , are made fast to the copping beam p . This beam is so called, because it is destined not merely to keep the spindles upright by the rings attached to it, but, at the same time, to raise and lower along the spindles the bobbins which rest on these rings; for which purpose the two racks, or toothed bars m 2 m 2 , made fast to it, are designed, as will be presently explained. To effect the revolution of the spindles, there are attached to the main shaft c′ two whorls or pulleys e′ f′ , each bearing four grooves of equal diameter. Each of these pulleys puts one half of the spindles in motion, by means of a cord, which, after going round the whorls k , turns four times about the pulleys of the shaft c′ . Two guide pulleys h′ , each four-grooved, and two others i′ , with a single groove, which turn independently of the others, upon the above shaft, serve to give the whorl cords the proper direction, as well as to keep them tight. The spindles revolve 200 times or thereby in the minute; and therefore impart two turns or twists to every three inches of the roving. The revolution of the bobbins is independent of that of the spindles, although it likewise proceeds from the shaft c′ , and differs from it in being a continually retarded motion. The simplest method of effecting this motion, is by means of the wooden or tin plate cone k′ ′ , which revolves equally with the shaft c′ , and at the same time slides along it. IMG:4147767755307473660_illo0358.png:Cone to drive bobbin The manner in which this operates is shown in section in fig. 336. Here, we perceive the rod q 2 , which extends from the base towards the narrow end of the truncated cone, and p 2 a forked bearer or carrier made fast to the shaft c′ by a screw, which compels the cone by means of that rod, to obey the movements of c′ . In the large end of the cone there is an aperture, through which the bearer can be got at. The smaller end carries outside a projection o 2 , provided with a groove, which is embraced by the forked end of a rod q′ , fig. 337. , that serves to shove the cone along upon the shaft c′ . Directly under the cone, there is an upright round pillar p′ , upon which the holder o′ of the two guide pulleys l′ is adjustable. A bar r 2 placed along-side of the holder, prevents its turning round, but allows it to slide along p′ by friction. The weight of the holder and the pulley is sufficient to distend the endle band n′ , which runs from the cone k′ , through under the pulley l′ , and round the small drum m′ on the shaft s 2 . A pulley or whorl t 2 with four grooves, is made fast by means of a tube to this shaft, and slides along it backwards and forwards, without ever ceasing to follow its revolutions. The shaft po e es for this purpose a long fork, and the interior of the tube a corresponding tongue or catch. There is besides upon the tube beneath the pulley, at u 2 , a groove that goes round it, in which the staple or forked end of an arm like v 2 , fig. 333. , made fast to the copping beam p , catches. By the up and down movement of that beam, the pulley t 2 takes along with it the arm that embraces the tube, which therefore rises and falls equally with the bobbins h′ , and their pulleys or whorls q . This is requisite, since the bobbins are made to revolve by the pulleys t 2 , by means of 2 endle cords or bands. IMG:4147767755307473660_illo0359.png:Bobbin adjustment The most intricate part of the mechanism is the adjustment, by which the revolution of the bobbins is continually retarded, and their up and down, or copping motion, along the spindles, is also retarded in like proportion. The vertical pulley f′ , (towards the left end of the shaft c′ ) has at its right side a somewhat larger disc or sheave g′ , with a perfectly uniform, but not a very smooth surface. Upon this sheave, a smaller horizontal pulley x′ rubs, whose upper face is covered with leather to increase the friction. The under end of the shaft y 2 of the pulley x′ turns in a step, which is so connected with the arm v′ of the large bent lever t′ v′ , that it always stands horizontally, whatever direction the arms of that lever may a ume. The shaft y 2 is steadied at top by an annular holder or bush, which embraces the fast arm x 2 with its forked end. Upon its opposite side, this arm carries a pulley y 2 , upon which a cord goes, that is made fast to the holder of the shaft y 2 , and loaded with the weight z′ . The weight pre es the pulley x′ against the surface of g′ , in such wise as to effect the degree of friction nece ary in order that the revolution of g′ may produce an uninterrupted revolution in x′ . A pinion w′ , whose length must be equal at least to the semi-diameter of the sheave g′ , is placed upon the under end of the shaft y 2 . It has 22 teeth, and takes into a 62-toothed horizontal wheel z 2 . Upon the upper end of this wheel the conical pinion a 3 is made fast, which may be changed for changing the speed, but usually has from 28 to 30 teeth. By this pinion the conical wheel b 3 is turned, which has 30 teeth, and whose shaft is c 3 . This shaft carries upon its opposite end a six-leaved pinion, d 3 , which takes into the calender wheel f 3 , formed with cogs like a trundle, upon the long shaft e 3 . In fig. 338. the wheel f 3 is exhibited with its pinion d 3 . Here we may remark that in the circumference of the wheel there is a vacant place, g 3 , void of teeth. When by the motion of the wheel, the pinion comes opposite to this opening, it turns round about the last tooth of the wheel, falls into the inside of the toothed circle marked by the dotted lines, and thus gives now an inverse movement to the wheel f 3 , while itself revolves always in the same direction. This reversed motion continues till the opening g 3 comes once more opposite to the pinion, when this turns round about the last tooth of that side, and begins again to work in the exterior teeth. Thus, by the uniform motion of d 3 and its dependent parts, the wheel f 3 , with its shaft e 3 , revolves alternately to the right hand and the left. That this result may ensue, the shaft c 3 of the pinion must be able to slide endwise, without losing its hold of a 3 and b 3 . This adjustment is effected by placing the end of the said shaft, nearest b 3 , in a box or holder i 3 , in which it can turn, and which forms a vertical tube to this box, as a downward prolongation which is fixed to the tail of the conical pinion a 3 . Fig. 339. shows this construction in section upon an enlarged scale. The second bearer of the shaft nearest d 3 , must po e likewise the means of lateral motion. When therefore the pinion d 3 shifts through the opening of the wheel f 3 outwards or inwards, its shaft c 3 , makes a corresponding small angular motion upon the pivot of a 3 , by means of the tube i 3 ; a 3 and b 3 remain thereby completely in geer with one another. The above-described alternate revolutions of the wheel f 3 serve to produce the up and down motions of the bobbins. The shaft e 3 has for this purpose two pinions n 2 n 2 , which work in the rack teeth m 2 m 2 of the copping rail p , and thus alternately raise and sink it with the bobbins which rest upon it. The weight of the copping beam and all its dependent parts, is poised by two counterweights m 4 , whose cords run over the pulleys o 4 o 4 o 4 , fig. 332. , and have their ends made fast to the frame, so as to make the upwards motion as easy as the downwards. The two upper pulleys out of the three of each weight, are fixed to the frame; the under one, round which the cord first runs, is attached to the copping beam, rising and falling along with it. IMG:4147767755307473660_illo0360.png: Figs. 340 and 341 enlarged (78 kB) As long as the friction disc x′ remains at the same height, the pulley g′ derives its motion from the same circle of the said disc, and the up and down motion of the copping beam is also uniform. But when that disc ascends so as to describe with its edge a small circle upon the face of g′ , its motion must become proportionally more slow. This is the method, or principle of retarding the copping motions of the bobbins. It has been shown, however, that the rotation of the bobbins should be also retarded in a progre ive manner. This object is effected by means of the cone k′ , which, as the band n′ progre ively approaches towards its smaller diameter, drives the pulleys or whorls q of the bobbins with decreasing speed, though itself moves uniformly quick with the shaft c′ . To effect this variation, the cone is shifted lengthwise along its shaft, while the band running upon it remains continually in the same vertical plane, and is kept distended by the weight of the pulley o′ . The following mechanism serves to shift the cone, which may be best understood by the aid of the figures 340. , 341. , and 337. A long cast iron bar m 3 , which bears two horizontal projecting puppets, o 3 o 3 , is made fast to the front upright face of the copping beam A . Through the above puppets a cylindrical rod n 3 pa es freely, which is left out in fig. 337. , that the parts lying behind it may be better seen. Upon this rod there is a kind of fork, p 3 p 3 , to which the alternating rack bars q 3 are made fast. The teeth of these racks are at unequal distances from each other, and are so arranged, that each tooth of the under side corresponds to the space between two teeth in the upper side. Their number depends upon the number of coils of roving that may be required to fill a bobbin; and consists in the usual machines of from 20 to 22. The rod n 3 may be shifted in the puppet o 3 , like the fork p 3 of the rack-rod, upon the rod n 3 , and along the surface of m 3 , where two wings u 3 u 3 are placed, to keep the fork in a straight direction. Upon the bar m 3 , there are the pivots or fulcra of two stop catches w 3 x 3 , of which the uppermost pre es merely by its own weight, but the undermost by means of a counterweight y 3 , against the rack, and causes them thus to fall in between the teeth. In fig. 341. , v 3 shows the pivot of the catch or detent w 3 by itself, the detent itself being omitted, to render the construction plainer. A pushing rod l 3 , upon which there is a pin above at s 3 , that pa es behind the rack rod, between this and the bar m 3 , has for its object to remove at pleasure the one or the other of the two catches; the upper, when the upper end of the rod pushes against it; the under, by means of the above mentioned pin s 3 . Both the catches are never raised at once, but either the under or the upper holds the rack bar fast, by pre ing against one of the teeth. The vertical motion up or down, which the rod l 3 must take to effect the lifting of the catches, is given to it from the copping beam p ; since upon it a horizontal arm v 2 , fig. 341. , is fixed, that lays hold of that rod. Upon the pushing rod are two rings, h 3 and k 3 , each made fast by a screw. When the copping beam is in the act of going up, the arm v 3 at the end of this movement, pushes against the ring h 3 , raises up the rod l 3 , and thus removes the catch w 3 , fig. 337. , from the teeth of the rod q 3 , before which it lies flat. At the descent of the copping rail, v 2 meets the ring k 3 , when the motion in this direction is nearly completed, draws down the rod l 3 a little, by means of the same, and thereby effects the removal of the catch x 3 , fig. 337. , from the rod q 3 . Every time that one of the catches is lifted, the rack recovers its freedom to advance a little bit in the direction of the arrow; so far, namely, till the other catch lays hold upon the tooth that next meets it. The reason is thus manifest why the teeth of the upper and under sides of the bar q 3 are not right opposite to each other, but in an alternate position. From the rack-bar, the sliding of the cone k′ , and the raising of the shaft y 2 , each by minute steps at a time, is produced as follows :— A large rectangular lever t 1 , v 1 , whose centre of motion is at p 4 , has at the upper end of its long arm t 1 , a long slot through which a stud r 3 upon the rack q 3 goes ( fig. 340. , 341. , 337. ,) so that the lever must follow the motions of the rack bar. The end of the short arm of the lever bears, as already mentioned, the step of the shaft y 2 ; hence the friction disc x 1 will be raised in proportion as the rack bar advances, and will come nearer to the middle point of g 1 ; consequently, its revolution and the shifting of the bobbins will become slower. Upon the cylindrical rod n 3 , the piece s 1 s 1 furnished with a long slot is made fast, by means of a tube z 3 , ( fig. 337. ) and a screw. A fork u u , which by means of the screw nut a 4 is made fast in the slot, embraces the arm t 1 of the bent lever; and a tube r 1 rivetted to the surface of s 1 , is destined to take up the draw rod q 1 of the cone k 1 , fig. 337. A weight f 4 , whose cord b 4 is made fast to the cylindrical rod n 3 , endeavours to draw this rod continually in the direction of the arrow. In consequence of this arrangement, every time that the pushing bar l 3 lifts up one of the catches, the cone k 1 , the lever t 1 v 1 , and by it the rack bar q 3 , are set in motion. It is obvious, that the motion of the cone may be made greater or le , according as the fork u u is fixed further up or down in the slot of s 1 . The number of the teeth upon the bar q 3 is so ordered, that the bobbins are quite full when the last tooth has reached the catch and is released by it. The rack bar, being restrained by nothing, immediately slides onwards, in consequence of the traction of the weight f 4 and brings the machine to repose by this very movement, for which purpose the following construction is employed. A rectangular lever which has its centre of motion in g 4 is attached to the side face of the beam A , and has at the end of its horizontal arm a pulley d 4 , over which the cord b 4 of the counterweight f 4 is pa ed. The end of the perpendicular arm is forked and embraces the long and thin rod k 4 , to whose opposite end the fork l 4 is made fast. Through this fork the band which puts the machine in motion pa es down to the pulley a 1 . With the bent lever another rod c 4 is connected at h 4 , which lies upon the puppet e 3 with a slot at e 4 , and hereby keeps the lever g 4 in its upright position notwithstanding the weight f 4 . In the moment when, as above stated, the rack bar q 3 becomes free, the arm p 3 of its fork pushes in its rapid advance against the under oblique side of e 4 , raises this rod, and thereby sets the lever g 4 free, whose upright arm bends down by the traction of the weight, drives the rod k 4 before it into the ring i 4 fastened to it, and thus by means of the fork l 4 shifts the band upon the loose pulley b 1 . But the machine may be brought to repose or put out of geer at any time merely by shifting the rod k 4 with the hand. The operation of the bobbin and fly frame may be fully understood from the preceding description. A few observations remain to be made upon the cone k 1 , the rack-bar q 3 , and the speed of the work. When we know the diameter of the empty bobbins, and how many turns they should make in a given time in order to wind-on the sliver delivered by the fluted rollers and the spindles; when we consider the diameters of the spindle pullies q , and t 2 , as also the drum. m 1 , fig. 332. , we may easily find the diameter which the cone must have for producing that number of turns. This is the diameter for the greatest periphery of the base. The diameter of the smaller is obtained in the same way, when the diameter of the bobbins before the last winding-on, as well as the number of turns nece ary in a given time, are known. A bobbin and fly frame of the construction just described delivers from each spindle in a day of twelve hours, from 6 to 8 lbs of roving of the finene of 1 1 ⁄ 2 English counts. One person can superintend two frames, piece the broken slivers, and replace the full bobbins by empty ones. The lo of cotton wool in this machine consists in the portions carried off from the torn slivers, and must be returned to the lapping machine.