OTHER PROCESSES IN COTTON SPINNING.
The Ring Spinning Machine.—In a former chapter it was shown how within the space of two decades the three rival spinning machines of Hargreaves, Arkwright and Crompton were introduced, also it was pointed out, that Crompton's machines contained the best points of both of his predecessors. The mule did not immediately become the sole spinning machine. From the outset there was a close contest between the continuous spinning machine of Arkwright and the intermittent spinning machine of Crompton. It was not long, however, before the mule asserted its superiority over the water frame for fine muslin yarns, and for weft yarns. Eventually the water frame was relegated to the production of strong warp yarns, and later still it has come to be largely utilised as a doubling machine. As a matter of fact, it is contended by experts of the present day, that no machine ever made a rounder and more solid thread than the water frame, or flyer-throstle, as it has been called in its improved form.
Fig. 30.—Ring spinning frame.
During the last thirty years, a revolution practically in cotton spinning has been gradually brought about, and even to-day active developments are to be seen. The continuous system of spinning, which for a time had to take a second place, now appears to be again forging ahead, and looks as though it would supersede its more ponderous rival. Especially in countries outside England is this the case, for it is found that the method of ring spinning preponderates, and even in England the number of spindles devoted to continuous spinning is constantly increasing.
This change has chiefly been brought about by what may be termed a revolution in the winding and twisting mechanism of the continuous spinning machine itself.
Arkwright's flyer and spindle, after improvement by subsequent inventors, could not be revolved at anything like the speed of the spindle of the mule, and, in addition to this, the yarn had to be wound always upon the bobbin, very much after the style of the bobbin and fly frames previously described.
Experiments, however, were repeatedly made in the direction of dispensing with the flyer altogether, and some thirty years ago these unique spinning frames had attained very general adoption in the United States of America, where the comparative dearth of skilled mule spinners had furnished an impetus to improvement of the simple machine of Arkwright.
About this time, the attention of certain English makers being directed to the success of the new spinning frames in America, led to their introduction into England. But little time elapsed before they received a fair amount of adoption, but for many years they had a restricted use, viz., for doubling, that is, the twisting of two or more spun threads together, to form a stronger finished thread.
In this way, they were, strictly speaking, rivals of the throstle doubling frame more than the spinning mule.
By and by, however, the time came when the new frames began to be adopted as spinning machines, and to-day there are many English and foreign mills containing nothing else in spinning machines on the continuous system except these. In not a few mills in different countries, both types are found running.
A careful glance at the picture of this rival of the mule, will help in the following description of it:—
The flyer which is to be seen on the old Saxony wheel, and which was perpetuated in the celebrated machine of Arkwright, is entirely dispensed with, and all its functions efficiently performed by apparatus, simple in itself; it is yet capable of high speed and heavy production.
First of all, there is a vastly improved and cleverly constructed form of spindle, by which, in the latest and best makes, any speed can be attained which is likely to be required for spinning purposes.
Perhaps the apparatus which plays the most important part in performing the duties of the displaced flyer, is a tiny "traveller" revolving round a specially made steel ring about 2 inches in diameter.
The use of these two latter gives the distinctive names of "Ring-spinning" to the new system and "Ring Frame" to the machine itself.
In describing this system of spinning the creel of rovings to be operated upon, and the drawing rollers being practically identical with machines already described, little here is required to be said of them, but there is, however, a modification in the arrangement of the rollers which is referred to later on.
After leaving the rollers, a thread of yarn is conducted downwards and passed through the "travellers," which may be seen in the illustration, and then attached to the bobbin. The "traveller" is a tiny ring made of finely tempered steel. It is sprung upon the edge of the ring shown in the frame, and which is specially shaped to receive the tiny ring or traveller referred to.
The bobbin in this case is practically fast to the spindle—unlike any other case in cotton-spinning machinery—and it is therefore carried round by the spindle at the same rate of speed.
As the spindle and bobbin revolve, they pull the traveller round by the yarn which passes through it, being connected at one end to the bobbin and the rollers above forming another point of attachment. If the reader will look carefully at the illustration he will see how twist is put in the yarn. The joint action, then, of bobbin, traveller and fixed ring, is to put the necessary twist in the yarn which gives it its proper degree of strength. If no fresh roving from the rollers were issuing for the moment, the small portion of thread reaching from the rollers to the bobbins would simply be twisted without any "winding-on" taking place. As a matter of fact, the roving always is issuing from the rollers, and "winding-on" of the twisted roving is performed by the traveller lagging behind the bobbin in speed, to a degree equal to the delivery of roving by the rollers. It will be remembered that in the old flyer-throstle "winding-on" was performed by the bobbin lagging behind the spindle, a procedure which is impossible on the ring frame.
There is also an arrangement of the mechanism for guiding and shaping the yarn upon the bobbins in suitable form, the action being as nearly as possible an imitation of the mule.
For a number of years after the introduction of these frames, it was found that the threads often broke down owing to the twist not extending through the roving to the point where it issued from the rollers. This was eventually remedied by placing the drawing rollers in a different position, thus causing the thread running from the rollers to the traveller to approach more to the vertical; this constituting the modification which has just been referred to previously.
Another difficulty was experienced in the fact that during spinning the threads would sometimes fly outwards to such an extent that adjacent threads came in contact with each other, causing excessive breakage. This was technically termed "ballooning," and has been very satisfactorily restricted by the invention of special apparatus.
At the present time, therefore, a contest between the two rival systems of continuous spinning which were in bitter antagonism over a century ago, is waging a more fiercely contested fight than at any previous time.
As the case stands to-day, the mule is retained for nearly all the best and finest yarns as yet found; the most suitable for them, just as it was when Crompton got 25s. per pound for spinning fine muslin yarns on his first mule.
In many cases, also, yarn is specially required to be spun upon the bare spindle as on a mule, as for instance when used as weft and put into the shuttle of a loom. It is probably the very greatest defect of the ring frame that it can only, with great difficulty, be made to form a good cop of yarn on the bare spindle, although thousands of pounds have been spent on experimenting in that direction. How soon it may be accomplished with commercial success cannot be known, as a great number of individuals are constantly working in that direction. If it does come about, there can be no doubt that the ring frame will receive a still further impetus.
Even now, for medium counts of yarn it is much more productive than the mule, owing to its being a continuous spinner. Another vast advantage that it possesses is the extreme simplicity of its parts and work as compared with the mule. Because of this, women and girls are invariably employed on the ring frames, whereas it requires skilled and well-paid workmen for the mules.
The Combing Machine.—As compared with the Scutcher, the Carding Engine and Mule, the Comber is a much more modern machine. Combing may be defined as being the most highly perfected application of the carding principle.
The chief objects aimed at by the comber are:—To extract all fibres below a certain length; to make the fibres parallel; and to extract any fine impurities that may have escaped the scutching and carding processes.
It is worthy of note that although nearly all the great inventions relating to cotton-spinning have been brought out by Englishmen, the combing machine is a notable exception. It was invented a few years prior to 1851 by Joshua Heilman, who was born at Mulhouse, the principal seat of the Alsace cotton manufacture, in 1796.
Like Samuel Crompton—the inventor of the mule—Joshua Heilman appears to have possessed the inventive faculty in a high degree, and he received an excellent training in mathematics, mechanical drawing, practical mechanics, and other subjects calculated to assist him in his career as an inventor.
Heilman was the inventor of several useful improvements in connection with spinning and weaving machinery, but the invention of the comber was undoubtedly his greatest achievement.
He was brought up in comparatively easy circumstances, and married a wife possessing a considerable amount of money; but all that both of them possessed was swallowed up by Heilman's expenses in connection with his inventions, and he himself was only raised from poverty again by the success of the comber shortly before his death, his wife having died in the midst of their poverty many years previously.
After Heilman became possessed of the idea of inventing a combing machine, he laboured incessantly at the project for several years, first in his native country and subsequently in England. The firm of Sharpe & Roberts, formerly so famous in connection with the self-actor mule, made him a model, which, however, did not perform what Heilman required.
Afterwards he returned again to his native Alsace still possessed with the idea, and finally it is said that the successful inspiration came to him whilst watching his daughters comb out their long hair. The ultimate result was that he invented a machine which was shown at the great exhibition of London in 1851 and immediately attracted the attention of the textile manufacturers of Lancashire and Yorkshire.
Large sums of money were paid him by certain of the Lancashire cotton spinners for its exclusive use in the cotton trade. Certain of the woollen masters of Yorkshire did the same, for its exclusive application to their trade, and it was also adopted for other textiles, although Heilman himself only lived a short time after his great success.
It must be understood that the comber is only used by a comparatively small proportion of the cotton spinners of the world. For all ordinary purposes a sufficiently good quality of yarn can be made without the comber, and no other machine in cotton spinning adds half as much as the comber to the expense of producing cotton yarn from the raw material.
To show this point with greater force, it may be mentioned that the comber may make about 17 per cent. of waste, which is approximately as much as all the other machines in the mill put together would make.
Its use, however, is indispensable in the production of the finest yarns, since no other machine can extract short fibre like the comber. It is seldom used for counts of yarn below 60's and often as fine yarns as 100's or more are made without the comber. In England its use is chiefly centred in the localities of Bolton, Manchester, and Bollington, although there is a little combing in Preston, Ashton under Lyne, and other places.
Perhaps its greatest value consists in the fact that its use enables fine yarns to be made out of cotton otherwise much too poor in quality for the work; this being rendered possible chiefly by the special virtue possessed by the comber of extracting all fibres of cotton below a certain length. This of course has led to the increased production and consequently reduced price of the better qualities of yarn.
Reverting now to the Heilman Comber as it stands to-day, an excellent idea of the machine as a whole will be gathered from the photograph in [Fig. 31].
There are usually six small laps being operated upon simultaneously in one comber. Each small lap being from 7½ inches to 10½ inches wide, being placed on fluted wooden rollers behind the machine, is slowly unwound by frictional contact therewith, and the sheet of cotton thus unwound is passed down a highly polished convex guide-plate to a pair of small fluted steel rollers.
Both the wooden and the steel rollers have an intermittent motion, as indeed have also all the chief parts of the machine concerned in the actual combing of the cotton. The rollers, during each intermittent movement, may project forward about ⅜ of an inch length of thin cotton lap.
Fig. 31.—Combing machine.
By this forward movement the cotton fibres are passed between a pair of nippers which has been for the instant opened on purpose to allow of this action. Immediately the cotton has passed between the nippers, the feed rollers stop for an instant and the jaws of the nippers shut and hold the longer of the cotton fibres in a very firm manner.
The shorter fibres, however, are not held so firmly, and are now combed away from the main body of the fibres by fine needles being passed through them. The needles are fixed in a revolving cylinder and are graduated in fineness and in closeness of setting, so that while the first rows of needles may be about 20 to the inch, the last rows may contain as many as 80 to the inch, there being from 15 to 17 rows of needles in an ordinary comber.
The short fibres being combed out by the needles are stripped therefrom, and passed by suitable mechanism to the back of the machine to be afterwards used in the production of lower counts of yarn.
The needles of the revolving cylinder having passed through the fibres, the nippers open again and at the same time another row of comb teeth or needles, termed the top comb, descends into the fibres. The fibres now being liberated, certain detaching and attaching mechanism; as it is termed, is brought into action, and the long fibres are taken forward, being pulled through the top comb during this operation. Thus the front ends of the fibres are first combed and immediately afterwards the back ends of the same fibres are combed. During the actual operation of combing each small portion of cotton, the latter is quite separated from the portion previously combed, and it is part of the work of the detaching and attaching mechanism to lay the newly combed portion upon that previously combed. From a mechanical point of view, the detaching and attaching mechanism is more difficult to understand than any other portion of the comber, and it is no part of the purpose of this "story of the Cotton plant" to enter into a description of this intricate mechanism.
Sufficient be it to say that the combed cotton leaves the detaching rollers in a thin silky-looking fleece which is at once gathered up into a round sliver or strand and conducted down a long guide-plate towards the end of the machine. This guide-plate is clearly shown in the photograph of the comber, where also it will be seen that the slivers from the six laps which have been operated upon simultaneously are now laid side by side.
In this form the cotton passes through the "draw-box" at the end of the comber, and being here reduced practically to the dimensions of one sliver it passes through a narrow funnel and is placed in a can in convenient form for the next process.
When the combing is adopted, it precedes the drawing frame, which has previously been described, and the cans of sliver from the comber are taken directly to the draw-frame.
For intricacy and multiplicity of parts of mechanism, the comber is second only in cotton-spinning machinery to the self-acting mule, and is probably less understood, since its use is confined to a section of the trade. The latest development is the duplex comber, which makes the extraordinarily large number of one hundred and twenty nips per minute, as compared with about eighty-five nips per minute for the modern single nip comber. All this is the result of improvement in detail, as the principle of Heilman's Comber remains the same as he left it. It ought to be added that other types of comber have been adopted on the continent with some show of success.
Fig. 32.—Sliver lap machine.
Sliver Lap Machine.—Combing succeeds carding and is practically a continuation of the carding principle to a much finer degree than is possible on the card. The Carding Engine, however, makes slivers or strands of cotton, while the comber requires the cotton to be presented to it in the form of thin sheets. It therefore becomes requisite to employ apparatus for converting a number of the card slivers into a narrow lap for the comber.
The machine universally employed is termed "The Sliver Lap Machine," or, in some cases, "The Derby Doubler," and a modern machine is shown in the photograph forming [Fig. 32].
In this case, eighteen cans are placed behind the machines, and the sliver from each can is conducted through an aperture in the back guide-plate designed to prevent entanglements of sliver from passing forward. Next each sliver passes over a spoon lever forming part of a motion for automatically stopping the machine when an end breaks. The eighteen slivers now pass side by side through three pairs of drawing rollers with a slight draft, and between calender rollers to a wooden "core" or roller. Upon this roller the slivers are wound in the form of a lap, being assimilated to one another by the action of the drawing and calender rollers.
Special Drawing Frame.—In order to have the fibres of cotton in the best possible condition for obtaining the maximum efficiency out of the combing action, it is the common practice to employ a special drawing frame between the card and the sliver lap machine.
As described elsewhere in this little story, the use of the drawing frame is to make the fibres of cotton more parallel to each other by the drawing action of the rollers, and to produce uniformity in the slivers of cotton by doubling about six of them together and reducing the six down to the dimensions of one. In the case under discussion the slivers from the card are taken to the special drawing frame and treated by it, and then passed along to the sliver lap machine as just described.
Fig. 33.—Ribbon lap machine.
Ribbon Machine.—Quite recently a machine has come slightly into use designed to supersede this special drawing frame. This new machine is termed the "Ribbon Lap Machine," and it may be described as a variation of the principle of the machine it is designed to supersede. The difference is this, that, whereas the drawing frame doubles and attenuates slivers of cotton, the Ribbon Machine operates upon small laps formed of ribbons or narrow sheets of cotton. By this treatment, the evening and parallelising benefits of the drawing frame are secured, with the addition of a third advantage, which may be briefly explained. The slivers, which in the sliver lap machine are laid side by side so as to form a lap, have a tendency to show an individuality so as to present a more or less thick and thin sheet to the action of the nippers of the comber. The latter, therefore, hold the cotton somewhat feebly at the thin places, thus allowing the needles of the revolving cylinder to comb out a portion of good cotton. When the Ribbon Lap Machine is employed, the slivers from the card are taken directly to the Sliver Lap Machine and the laps made by this machine are passed through the Ribbon Machine. Six laps being operated upon simultaneously by the rollers, are laid one upon another at the front so that thick and thin places amalgamate to produce a sheet of uniform thickness. The use of the Ribbon Machine is limited at present owing to its possessing certain disadvantages.