Sewing Machine, a mechanical contrivance for uniting fabrics by means of needle and thread. The earliest inventions for this purpose were attempts to imitate hand sewing, making a running through-and-through stitch with but a needleful of thread. This being impracticable in consequence, among other defects, of the wearing of the thread, it was sought to produce the old crochet stitch by means of machinery. The first needle suitable for use in sewing machines was introduced by Charles F. Weisenthal, to whom a patent was granted in England June 24, 1755. It was pointed at both ends, with an eye in the middle, for passing each way through the cloth without being turned around; but it was only used for hand embroidery. The first application of machinery was contained in. a patent to Robert Alsop in England, dated March 22, 1770, for embroidering in a loom with one, two, or more shuttles. Machine embroidery with a large number of needles was patented by John Duncan, May 30, 1804. He used hooked needles, attached in a straight line to a horizontal bar, the forward motion of which carried all the hooked ends through the cloth, when, on being supplied with thread by a feeding needle, the reverse motion carried back loops which passed through and secured those of the previous stitch.
Patterns were worked by a sliding motion of the fabric with its vertical frame. This was the first important step in embroidering machinery, which was carried to great perfection in the machine of Heil-mann. This however used Weisenthal's two-pointed needle with the eye in the middle, and also nippers to pull the needle through, afterward used by Greenough. There has lately been found in the archives of the English patent office a patent for a sewing machine made by Thomas Saint, dated July 17, 1790, which has excited considerable interest and surprise in consequence of its possessing many of the elements of successful modern sewing machines. This might have been used to some extent for sewing leather, but could not have succeeded with woven fabrics containing fibres, for they would have been caught in the forked needle by which the thread was pushed through. It was intended, as the patent states, "for quilting, stitching, and making shoes and other articles by means of tools and other machines." It had an arm, upon the overhanging end of which there was a vertically reciprocating straight needle. The arm also supported a spool which gave out its thread continuously. It had a horizontal cloth plate, made a chain or crochet stitch, and had thread tighteners above and below.
In fig. 1, representing this machine, a is the bed plate, b an upright post bearing a horizontal overhanging arm, upon the end of which are placed a needle f and an awl g, which were adjusted by means of set screws, and moved by cams h and i, on the shaft k. The needle was notched at its lower end, to push the thread through the hole made by the awl, and thus form a loop. The work was supported on a box l, sliding between guides m, m, and moved by a screw n turned by a toothed wheel o, which in turn was moved by an arm upon the shaft k. One loop was carried over the other by the bent point of the spindle d in a manner similar to that which has been employed in some chain-stitch machines. The screw r adjusted the box l on the guide plate. In 1830 B. Thimo-nier patented a sewing machine in France, 80 of which, made of wood, were in use in 1841 for sewing army clothing at a shop in Paris. They were destroyed by a mob, as the Jac-quard loom and Hargreaves spinning jenny had been years before; but during the revolution of 1848 Thimonier was again at work with other machines capable of making 200 stitches a minute.
The mob again broke up his establishment, threatened his life, and defeated his enterprise, and he died in poverty in 1857. Like that of Saint, his machine had a vertical needle descending from an overhanging arm, the fabric being fed upon a horizontal table by hand. The needle was driven by a treadle instead of a crank as in Saint's machine, and was carried back by a spring. It had the form of a crochet hook, and being driven through the fabric caught a lower thread from a thread carrier and looper beneath, and brought a loop which it laid upon the upper surface, and at the next passage brought up another and passed it over the loop previously made, thus making a double loop or chain stitch, with the loops on the upper side. The Thimonier machine which was patented in France Aug. 5, 1848, and in the United States Sept. 3, 1850, was an improvement upon that of 1830, but retained its principal features, the needle being still worked by a treadle and spring. It is said that between 1832 and 1834 Walter Hunt of New York made a sewing machine in which he used an eye-pointed needle, attached to the end of a vibrating arm, which carried a thread through the fabric and made a loop which was pierced by a shuttle carrying another thread, making what is known as the lock stitch.
When he applied for a patent in 1854 he was refused, because the main features which he claimed for his machine had been patented eight years previously by Elias Howe, and it was held that his right to a patent was forfeited by abandonment. A machine for making a through-and-through or shoemaker's stitch was patented Feb. 21, 1842, by J. J. Greenough of Washington. The needle was pointed at both ends, with the eye in the middle, and was drawn through one way and then the other by a pair of pincers travelling on a track and opening and closing automatically. It was designed for sewing leather and other hard material, and an awl pierced the hole in advance of the needle. The leather was held between clamps, which by means of a rack could be moved each way alternately to make a back stitch, or continuously forward to make the shoemaker's stitch. The needle was threaded with a length of thread, and required refilling. The rack, after passing forward its length, was each time set back. Another form of a through-and-through sewing machine employs fluted rollers, between which the cloth is drawn and crimped, and in this condition forced upon the needle and thence on the thread.
In 1844 a patent was granted in England to Fisher and Gibbons for working ornamental designs by machinery, in which two threads were looped together, one passing through the fabric, the other looping with it on the surface without passing through. Curved needles were used beneath the fabric, and other needles with looped guides or retainers above, the several sets being arranged in a row across the machine. When the point of the curved needle ascended through the fabric, the point of the upper needle entered between it and its thread, and when the curved needle descended it left upon the upper needle a loop which was then pressed further on by the guide. The fabric was moved according to the pattern required, when the curved needle again ascended and the upper needle passed its thread around it so as to be withdrawn through the loop previously on its stem. After this the upper needle, again advancing, entered between the curved needle and its thread as before, producing a highly ornamental double chain stitch. - Sewing machines may be divided into four classes, according to the character of the stitch they make: 1, those making the through, either continuous or back stitch; 2, those making the lock stitch; 3, those making a single-thread chain stitch, either the ordinary crochet stitch, or a twisted one called a twisted loop stitch; and 4, those making a double-thread loop or chain stitch.
The through-and-through stitching machines, being no longer in use, will not be further described. The invention of the lock stitch has been claimed for Walter Hunt, but it has been generally conceded by sewing machine inventors that the machine of Elias Howe was independently devised; and as it had a more perfected construction and formed the basis upon which subsequent improvements were made, fitting it for a practically working machine, and obtained the first patent, he has been generally accredited as the originator of the lock-stitch machine. Howe's machine, as patented in 1846, used a grooved and curved eye-pointed needle, carried upon the end of a vibrating arm, which passing through the cloth formed a loop through which a shuttle passed another thread. The needle moved in a horizontal direction, the cloth being held in a vertical position by pins projecting from a baster plate, which was moved intermittingly by a toothed wheel. On reaching the end of the plate, the machine was stopped, the baster plate returned to its original position, and the cloth again attached. This construction prevented the successful use of the machine.
One of its serious wants was a device by which the cloth could be moved along in such a way as not to interfere with the functions of the needle, and this defect was then common to all sewing machines. Such a device is called the "feed," and was sought for a long time before the desired end was accomplished. One of the first steps was to make the needle vibrate vertically, and move the fabric along, or feed it on a horizontal plate, by the action of a notched wheel which rotated with its upper edge just passing through a slot in the horizontal plate. An intermitting motion was given to this wheel, which was sought to be so timed as to alternate with the passage of the needle through the cloth; but this arrangement was far from perfect, although it was for a time used with some success in the early machines made by Mr. I. M. Singer and others. It was not till the device known as the A. B. Wilson "four-motion feed" was introduced that this feature of the sewing machine approached perfection. This device consists in moving a serrated bar, in a slot in the horizontal plate upon which the cloth is fed, in the direction of the four sides of a parallelogram.
The teeth carry the cloth forward while moving horizontally a short space above the surface of the plate; the bar then drops (the second motion), then passes backward horizontally beneath the plate (the third motion), and rising brings the teeth through the slot and above the surface (the fourth motion). The directions of these motions are indicated in fig. 2. The motion which carries the cloth forward is so timed by cams upon a wheel, or by eccentrics or other devices, as to take place while the needle is raised above the cloth, and never to interfere with its passage. The four motions are obtained in the Willcox and Gibbs machine by a single eccentric, and the number of stitches to the inch may be determined by a device which employs a dial with numbers upon it, showing through an opening in the cloth plate. Most of the sewing machines now in use are lockstitch machines, the stitch being precisely the same in all, and the principle upon which it is formed being nearly the same also. It is always made by passing loops of thread through the fabric by means of an eye-pointed needle, and then passing another thread through these loops, this latter part of the process being usually produced by means of a shuttle which is made to pass through the loops.
When the shuttle thread is pulled back half way through the fabric, the stitch has the construction shown in fig. 3, where the threads are raised from the cloth to give a better view. It will be seen that the position of either thread is the same in relation to either side of the cloth; but when the loops formed by the needle are not drawn into the body of the fabric, the shuttle thread will lie straight on the under side of the cloth, as shown in fig. 4. The manner of making the stitch with the shuttle is shown in fig. 5. In most machines the needle vibrates in a right line, being carried by a vertically moving needle bar which slides in grooves. A shuttle bar carrying a shuttle underneath the cloth plate is made to pass through the loop, which opens to receive it when the needle begins to retract. The two bars, the needle bar and the shuttle bar, being actuated by the same motor, are so adjusted that their times of motion exactly correspond to each other. The shuttle, passing backward with its bobbin while the loop is drawn up into the cloth, only carries its thread through the loops in one direction, and unwinds just as much thread at each passage as corresponds to the curved length of the thread necessary to form a stitch.
It is prevented from unwinding more than this by having the thread held by a device called a tension. The thread which is delivered by the needle is also held in the same way, in consequence of which the loop is retracted when the needle is drawn upward, the degree of retraction depending upon the tension, or the tightness with which the thread is held. The celebrated Singer and Howe machines are of this class, as also the well known Weed, Domestic, Florence, Remington, Wilson, American, Secor, and others. The Florence machine differs from the other lock-stitch machines in having a curved needle attached to the end of a vibrating arm, instead of being carried by a needle bar moving vertically in guides; and there are various ways of actuating the needle bars in all of them. Another form of lockstitch machine, instead of causing a shuttle or movable bobbin to pass through the loop formed by the needle, catches this loop by means of a rotary hook and passes it over a stationary bobbin, which answers to the movable shuttle, and may be regarded as a stationary shuttle.
The lock stitch of the Wheeler and Wilson machine may be made by hand, and its formation explained by reference to fig. 6. Take a piece of fabric, c, an ordinary needle, h, threaded with e, and a small ball of thread, f; tie the ends of the two threads together, thrust the needle threaded head first through the fabric, and instead of passing the ball of thread through the loop e, hold the ball and pass the loop around it; withdraw the needle and draw the interlocked portion of the threads, e and z, into the fabric. A succession of stitches thus made will form a seam. The lock stitch is formed by the machine in an analogous manner. The upper thread e is carried by an eye-pointed needle (35, fig. 7), and a loop of it is thrust through the fabric by the needle; the loop is then entered by the point a of the rotating hook. The lower thread z is carried upon a thin metallic bobbin lying in the concavity of the hook, where it is held by a concave ring (not shown). The bobbin has no axis, so that a loop of thread can be freely passed around it.
The loop of the upper thread is enlarged by the hook (fig. 8), and carried forward and around the bobbin containing the lower thread, as in fig. 9, and being drawn up as in fig. 8, in the process of enlarging the next loop, interlocks with it, and the point of interlocking is drawn into the fabric and forms a stitch. Wheeler and Wilson have made another form of lock-stitch machine, the invention of Mr. James A. House, which also employs a rotary hook, but completes a stitch at each revolution, drawing it up by a separate arm known as an independent "take-up." An eccentric attachment causes the hook to rotate more rapidly during one part of its revolution, and there is a "pad" or projection of steel on the revolving hook, or rather the wheel that carries it, by which the under thread is held firmly during a short period, which assists in the completion of the stitch. This produces the "tension," which can be regulated while the machine is in motion, and differs therefore from that just described in the family machine, which depends upon the friction of the revolving hook against the bobbin. The new machine is made of different sizes, some very large and strong, for heavy manufacturing work. The needle, being straight, is capable of penetrating stout leather.
The medium sizes may also be used for tailoring as well as light domestic sewing. - The single-thread chain or crochet stitch is shown in fig. 10. It is formed by passing a thread through the fabric and making a loop, then making a second loop and passing it through the first, and again making a third and passing it through the second, and so on. This may be done with an eye-pointed needle and a reciprocating or vibrating hook, but does not form a very durable stitch, from its tendency to ravel. If, however, each loop is twisted, as shown in fig. 11, ravelling is difficult, and when the work is well done not liable to occur, except by design. A mechanism for producing such a twist was patented by J. E. A. Gibbs of Millpoint, Va. A rotating hook causes the relations of the threads on each side to become changed toward each other. The different parts of the hook are shown in fig. 12, in which 18 is the shank, 19 the point of the hook, 20 the "cast-off," and 21 the heel; K K is the shield for protecting the thread from oil. In fig. 13 the needle, having descended to the lowest point, carrying down the thread, has just begun to ascend; and a loop is thrown off on the back side of the needle just in time for the point of the hook to enter it.
As the needle rises, the hook, moving in the direction of the arrow, passes into the loop, drawing it down and spreading it. As the hook advances from this point the loop begins to twist; thread No. 1, fig. 14, moving to the right, slides off the shoulder at the centre of the hook and falls down to the shank, near the shield K, while the heel, 21, catches the back side of the loop 2, and swinging it around passes into the loop which is being reversed. As the hook still advances and the heel passes further into the loop, thread No. 2 slides into the angle at the centre of the hook, as seen in fig. 15. The loop is now completely reversed, thread No. 2 being on this side of the needle, and thread No. 1 on the back side. While the old loop thus twisted and spread out is held open on the body of the hook, the point 19 enters the new loop and carries it into the old one, as seen in fig. 16; and as the hook continues to revolve the cast-off, 20, passes out of the old loop and leaves it to be drawn up to the under side of the fabric, as in fig. 17, which completes the stitch.
One feature of the machine consists in the application of what is called an automatic tension, lately devised and patented by Mr. Charles H. Willcox. Instead of subjecting the thread to a continuous tension produced by partially confining it in a groove or clamp through which the motion of the machine draws it, it is made to pass between two disks held together by a spiral spring firmly enough to hold the thread inflexibly and draw it through the fabric to a definite distance until more is required to make a new loop, when it is instantly relieved by a little piston rod striking against the lower end of a rod attached to the upper disk. A uniformity in the drawing up of each stitch is thus secured, and as the necessity for change in tension when different sizes of thread or thicknesses of cloth are used is done away with, no provision is made for change by the operator. - The Grover and Baker machine makes what is called the double-loop stitch, employing two threads. Instead of passing a single thread through the loop formed by the eye-pointed needle in piercing the cloth, as in the lock-stitch machines, a loop made by a circular horizontally moving needle (fig. 18) below the cloth is passed through the former loop, and the needle at its next descent passes through the loop formed by the lower needle, so that the stitch is really formed by passing a loop of one of the threads through that of the other.
The construction of the stitch thus made will be understood by inspecting fig. 19, where the threads are widely drawn apart for the purpose of showing it. When the loops are properly drawn to their places underneath the cloth, a durable elastic stitch is produced, which is very desirable in elastic as well as other goods, and may be used with advantage in embroidery by using different sized threads. - In this article it has been sought to explain the actions of some of the principal sewing machines, without entering into the details of their construction or a description of the various attachments for hemming, felling, ruffling, cording, etc., or of buttonhole machines, which are either attachments to sewing machines, or made specially for this work, and which are employed with more or less perfection of execution.
Fig. 1. - Saints Sewing Machine, 1790.
Fig. 2. - Four-motion Feed.
Fig. 3. - Lock Stitch.
Fig. 4 - Lock Stitch.
Fig. 5. - Shuttle.
Fig. 10. - Crochet Stitch.
Fig. 11. - Twisted Loop Stitch.