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of the net, and tilted down, as if they were going to take up in their usual manner, except that they are drawn more forwards from the warp-threads, and let down at a greater distance therefrom, in order to leave room for the row of gatherers to be let down in front of the warp-threads, by a descending motion of the bar to which they are fixed, which is suspended and moved in the same manner as that described by Mr. Sneath, in his before-mentioned specification. And when the selected bobbincarriages, which are to furnish thread for the spots, are coming through the warp-threads, from the back into the front combs, the gatherers descend, and insert their lower ends amongst their bobbin-threads; there will thus be a gatherer on the left-hand side of each of those bobbin-threads which are to be gathered, and by putting the gatherers a little backwards, their lower ends become inserted amongst the bobbin-threads of the back row or division, as well as those of the front row. At the same time, also, that the bobbin-threads are coming forwards, the front points are moved a short distance backwards, in order to insert the extremities of their prolonged points amongst the threads, both back and front, (without racking the warp-threads); and as the prolonged front points stand on the right-hand side of each pair of selected bobbin-threads, and the gatherers on the left-hand, each pair of those threads are therefore included between a prolonged point and a gatherer.
This situation of the parts being attained, the row of gatherers are racked to the right, and the row of front points as much to the left, by simultaneous motions, so as to bend the pairs of selected bobbin-threads which are included between them, and bring those threads in contact with the left-hand sides of the extremities of the prolonged front points. This being done, the prolonged rising points become inserted between the lower extremities of the row of gatherers, in such a position, that the gatherers will retain the bobbin-threads that are bent across those points, and prevent them from slipping off the pointed extremities therof, as they would otherwise do. The pair of bobbin-threads being thus caught by the prolonged points, with the aid of the gatherers, the front points are raised up, with a tilting motion of the front point bar, similar to their ordinary taking-up motion, only their pointed extremities do not reach back to the warp-threads or gatherers, excepting the pointed extremities of the prolonged points, which act in concert with the gatherers.
The gatherers are raised with the front points, by a corresponding inotion, whereby they draw up the selected bobbin-threads, in loops, across the prolonged points, pulling off a requisite quantity of thread from each bobbin. When the front point bar has been carried up to its resting position, the extremities of its prolonged points (but of those alone) enter and pass throngh the spaces between the back points, at their proper places in the row thereof; and the said extremities of the prolonged points, with the loops of thread across them, rise a very little higher than the extremities of the back points, so as to place the loops exactly in front of the pointed extremities of the back points, the gatherers having hitherto prevented the loops from slipping backwards off the extremities of the prolonged points.
A this period the selected carriages begin to swing backwards, in the usual course of their vibrating motion, and, in so doing, the threads proceeding from them (and which form the said loops) begin to draw backwards, giving an additional tendency to the loops to slip backwards off the extremities of the prolonged points, if the gatherers did not prevent the same; but when the carriages have moved a little way backwards, the gatherers are raised upwards, so as to withdraw them entirely from their lateral contact with the prolonged front points, whereupon the loops of selected bobbin-threads slip suddenly backwards from off the extremities of those prolonged points, and become transferred to, and deposited upon, the pointed extremities of those back points which are on the left-hand sides of each of the prolonged points.
When the loops are so deposited over the back points, the result will be the same as would have been attained by the action of Mr. Sneath's hooks, or by the action of pointed wires, combined with such hooks, according to the present patentee's former patent.
The subsequent portion of the operation, for completing the curls of selected bobbin-threads around the back points, and around behind their corresponding warp-threads, in order to secure the curls, is to be performed according to Mr. Sneath's mode.
Another part of these improvements consists in applying additional taking-up and knocking-out cams, for the front pointbar, with a suitable racking-wheel, to rotary spotting machinery, constructed according to the aforesaid improvements on those of Mr. Sneath. These additional cams are to actuate the front point-bar, whilst the prolonged front points are operating, as above described, in concert with the gatherers, in order to form spots; which motions differ, in some small degree, from the usual takingup motions of the front point-bar, as before stated. The motions given by the said additional cams to the front point-bar, must be repeated at every complete vibration which the selected bobbincarriages make, in passing from the back to the front combs, and then re-passing from the front to the back.
These repetitions being differently timed from the usual takingup action of the front points, the ordinary cams, which actuate the front point-bar, during the making of the plain net, must be disengaged from their connection with that bar, at the instant that the operation of forming a row of spots is to commence. A new connection must, at the same instant, be made with
the additional cams, which are to become operative during the act of spotting ; then, after a row of spots is completed, and the operation of making plain net is to be resumed, the connections of the front point-bar must be changed, by an instantaneous motion, from the additional cams to the ordinary ones.
Another improvement consists in ornamenting bobbin net lace, with spots, formed by accumulated interweavings of two extra threads, which are introduced into the warp, at every place where a longitudinal row of spots are required to be made in the net. These extra threads are included in the twists made by the ordinary bobbin-threads and warp-threads, so as not to shew very perceptibly in the plain net their course from one place to another, and the two extra threads which are to form each longitudinal row of spots, proceed by separate courses along the net, in order to be less visible.
The spots are formed, at the required places, by the said extra threads crossing and re-crossing each other in contrary directions, before and behind three bobbin-threads, and two intermediate warp-threads, so as to form several short zig-zag courses across five adjacent threads, and thus produce flat woven spots. The manner of performing this, on the kind of bobbin net machinery, commonly called “Lever's machinery," is represented in Plate III., at fig. 1.
The machine has its warp-threads, and main guides, as usual, and two extra guide-bars, for the extra threads, one applied in the front, and the other at the back ; there being one opposite each place in the width of the net, where spots are required to be made. If the spots are to be disposed according to a chequered pattern, then two additional guide-bars a, b, in front, and two more c, d, at the back, will be requisite, the extra threads being held by their guides, in two different planes, from the main warp-threads; viz., one tier of extra threads in front, and the other tier at the back of those threads, so that the extra guides will be capable of shogging, independently thereof. The extra threads are supplied from two or four extra beams or threadrollers e, f, one to each guide-bar; and each roller must have a suitable connection with the usual apparatus of the point-bars, either back or front, for turning the roller round, in order that it may give off the exact quantity of thread required, at each time of taking up the extra threads.
The usual taking-up points must be removed, and a new set applied, with twice as many pins in a given width, the new pins or points being thinner than usual, and cast in leads, cranked downwards from the point-bars, to which they are screwed, so as to enable the points to go down very near to the tops of the carriages in taking up. These points will take up all the twists and crosses as fast as they are made, instead of what is termed “ hugging the twist,” and the Lever's machine will be better adapted
for this purpose, if its comb-bars and landing-bars are spread wider apart than usual at their lower edges, which may be done by bending the arms of the main joints, by which those bars are suspended, outwards, so as to leave more space between them for the extra guide-bars.
The points being so close together, one row cannot pass through the other, as usual, in taking up, with Lever's machinery, but one row must be always over the other row, in two levels, to which each row must be raised in its turn, and therefore suitable moveable pieces are interposed between the stop-screws, for limiting the descent of the tail-poles for each point-bar, in order thereby to limit the ascent of the row of points that took up last, to the lower of the two levels, and keep its points from striking the other row of points which took up previously, and which have reached the higher level; then as soon as the latter are withdrawn from the meshes of the net, their moveable piece is also withdrawn, in order to allow the other points to go quite up to the higher level, ready for those which were withdrawn to ascend, after taking up, without one row of points touching the other row. Or this may be done by prongs, fixed to each point-bar, overlapping each other, in the manner of what are called horns, which are pieces projecting from each point-bar, exactly in the range of the row of points belonging to that bar, and overlapping each other, so as to prevent the two rows of points from coming in contact.
The usual racking-wheels of Lever's machinery, on the upright axis, at the right-hand end of the machine, are to be changed for other racking-wheels, having a ratchet-wheel, of nine teeth, to turn them; and a set of racking-wheels must be suitably formed for racking the front comb-bar, and the main guide-bar, so as to produce all the movements usually given by the bars in Lever's machines, but in nine motions, instead of eight.
The two or four extra guide-bars a, b, c, d, for the extra guides, are to be racked by additional racking-wheels, applied on an upright axis of their own, at the left-hand end of the machine, turned by a distinct chopper, which, by a driver, actuates a large ratchet-wheel of forty-five teeth, fixed on the axis, turning it round one tooth, at the same moment tliat the ordinary racking-wheel is turned. The driver h, (the wheels are not shewn in the drawing) is jointed to one arm of an elbow-lever i, which plays upon an upright centre-pin j, fixed in a bracket, projecting from the frame; the other arm of the lever i, is acted upon by a projection k, affixed to one of those links g, called goose-necks, which is jointed to the front landing-bar, and reaches downwards and backwards beneath the fixed tye-bar, to the lower end of the driving tackle-lever, at the back of the machine. By this means, when the landing-bars are extended, the elbow-lever i, is moved by the projection k, and the driver h, is made to turn the ratchetwheel of forty-five teeth, one tooth, a re-acting spring being applied to pull back the lever i, when the projection k, retreats from it, as the landing-bars are closed.
An additional horizontal axis is placed behind the machine, on which are fixed seven cam-wheels, for producing the changes that are required to be made in the machinery, for ceasing to make plain net, and beginning to make spots, and vice versa. This back axis is caused to revolve by a ratchet--wheel, of forty-five teeth, fixed thereon, which is turned round, one tooth at a time, by a driver, acting on the lower part of it. The driver is jointed to the lower end of a short arm, which projects downward from the middle part of the usual horizontal back axis of the gooseneck or drawing tackle-levers; therefore the driver is put backwards, and turns the ratchet-wheel round one tooth at every time the landing-bars are closed, -this motion being given at the same moment that the ordinary catch-bar wheels are turned round one tooth.
The racking-wheels, on the additional upright axis, and those on the back-shaft, will complete a revolution in the same time, namely,—the racking-wheels and the ratchet-wheel, with nine teeth, on the ordinary upright axis, perform three revolutions, in order to make three complete rows of meshes, which corresponds to a motion of twenty-seven teeth of the forty-five teeth of the additional racking-wheels; after which, the said ratchet-wheel of nine teeth remains stationary, during the time it would take to revolve twice more, the pause being occasioned by the ordinary chopper having being disengaged, and during this pause a row of spots is made.
The point-bars must take up continually, during the making of the spots, so as to gather up and accumulate the extra threads into spots. Those extra threads, back and front, of which a pair are required to form each spot, are racked to the right and left, in contrary directions to each other, previous to the carriages passing and re-passing between the warp-threads, whilst all the other warp-threads remain stationary ; and the carriages are never divided or traversed, during the making of the spots. The points, back and front, alternately, must take up every time that the carriages are passed and re-passed, but as no twists or crosses will have been made, the points will only catch up the extra threads, whereof each pair, back and front, by the contrary racking motions, have been lain across two of the bobbin-threads, which have passed and re-passed, and also across the three warp-threads belonging to those bobbin-threads.
This mode of operating, during the making of the spots, requires that different arrangements of the parts of Lever's machinery should be made, from those by which plain net is made therein, viz., the catch-bar wheels are required to act differently, in order that the carriages may be passed and re-passed, without