2

1-1 in., the distance of the rise necessary for the formation of the loop, the second roller has also reached the point 2, the radius of which is shortened in., as the shuttle point was at first in. removed from the needle. The path 23 of the first roller is symmetrical with 12, the needle sinking the same distance as it had risen; in the same time the second roller has reached point 3, the radius of which is again shortened the length of the shuttle point as the cylindrical part of the shuttle must then just have reached the needle. The groove of the second roller now continues to approach the centre of the disc to point 4, corresponding with the position of the shuttle after the completion of its stroke. Till this moment, the needle has remained stationary, on which account 34 of the path of the first roller is circular shaped. From 4, the larger groove has only to fulfil the condition that its radius shall diminish as much as requisite, increasing on its return to point 1. The groove can therefore be symmetrical, and the axis of symmetry is found by connecting the centre of the disc with point 2. The point a of the groove, where the smallest radius occurs, must also lie in this axis. When the first roller has reached point 4, the shuttle must stand still till the eye of the needle has reached the sewing plate, this corresponds to the point 5 in the groove of the second roller. The piece 45 of the inner groove consists, therefore, of a concentric curve. The inner curve from 5 having no other condition to fulfil but that its radius should again increase to point 1, may also be made symmetrical. The curve 45 is halved, this central point connected with the centre of the disc, giving the axis of symmetry. The con

centric curve 1e having the radius, 01 is described. The choice of the point 1 is of importance for the size of the exterior curve. It is of course brought as near the inner curve as possible, but only so near that there may be at least in. between the two grooves at their nearest points.

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The disc is screwed on to the shaft which runs on a bearing 2 in. long. The other end of this shaft carries the feed eccentric, pq. Attached to the extreme end of the main shaft is the driving sheave.

The feed eccentric imparts motion to the feeder by means of a two-armed lever, zv, moving in a perpendicular plane, having its fulcrum at z, and a lever shaft, e, Fig. 15, running on screw points. The feeder arm, λ, Fig. 1, runs in a slot in the bracket arm, in. broad and in. deep, and is forked at its upper extremity. A flat spring presses against the feeder from left to right. The front end of the lever vibrating perpendicularly is attached to the feeder, being pressed downwards by a spiral spring attached to and σ. At its hinder end, on a horizontal pin, is a roller travelling on the cylindrical edge of the eccentric, thus effecting the rise and fall of the feeder. The lever shaft, Fig. 15, that is a shaft running parallel with the axis of the machine, has attached to both ends, and perpendicular to it, levers, the one of which, a, carries a rotating roller, c, working on the second screw-shaped surface of the feed eccentric, while the other, b, has affixed to its lower end a horizontal projecting stud, shown in Fig. 12, pressing the feeder from right to left, effecting its backward and forward motion. The stitch regulator acts on the

hinder lever of the lever shaft, and the arrangement is shown clearly in Fig. 8.

The feed motion just described only allows of the material when of a hollow shape, as coat-sleeves, uppers of boots, &c., being sewn round. But it is often necessary to sew these articles also longitudinally, and a second feed motion is therefore introduced, by which the material is advanced from the front towards the hinder part of the machine. This feeder is similarly constructed to the one just described, having for its guide the perpendicular groove, in the head of the bracket. The shape of this feeder is shown in Fig. 11, while that of the first is represented in Fig. 10. A spring presses this feeder towards the front of the machine, and for the purpose of imparting the requisite motion, the front lever of the lever shaft has affixed to its lower end, d, Fig. 12, not only the stud, c, but also a conical piece, e, acting upon the second feeder, and giving it a forward motion. Of course both feeders cannot be employed at the same time.

This machine is especially applicable to saddlers' work, the manufacture of boots, shoes, &c. The feed motion from above allows of very sharp curves being made, which are requisite in ornamenting the fronts of shoes, slippers, &c.

THE QUILTING-STITCH MACHINE WITH FIXED BOBBIN.

The lower part of the machine, Figs. 1, 2, and 3, Plate VII., consists of a cast-iron plate, a, provided with two bearings, b and d, in which the main shaft works, carrying the looper, f, constructed of steel. Between

these bearings is a cast-iron cylindrical piece, s, cast in one piece, with the feed eccentric, y, and the eccentric, r, for imparting motion to the needle by means of the needle lever, q s, working on the screw points, v v.

Close beneath the sewing plate, above and parallel to the main shaft, is the wrought-iron piece, &, working in a guide in the direction of the shaft. This piece (shown in Fig. 21) has a slot in the same direction, in which is a steel tongue, the right end of which is the serrated feeder foot, c, while the left end is fastened by a pin, e, in the slot. The rise of the tongue is effected by the feed eccentric pressing against the projection, b, the descent by its own weight. The forward motion is effected by the eccentric pressing against the carrier, ɛɛ, and the return by a spiral spring. The stitch regulator, &, Figs. 1, 2, 3, and Fig. 6, provided with an index, is inserted in the sewing plate to the left behind the feeder carrier.

The break or drag, Fig. 5, pressing against the cylindrical surface of the looper, consists generally of a small brush, less frequently of a piece of leather, and is attached by the screw, d, to an iron piece in the plate, a, which is screwed on to the right side of the right bearing, so that the brush may act upon the looper as before described.

The spool or the shuttle is fitted in a recess of the looper, and to prevent its falling out, the so-called eyepiece is employed, Fig. 8, consisting of a circular castiron ring having the same axis as the main shaft, attached at right angles to the carrier, d, on the lower surface of which is the guide, c, working in a corresponding slot in the bed-plate. This carrier is affixed

to the bed-plate by a thumb-screw, and has at its hinder end a projection, f, which is also provided with a screw by which the distance of the eye-piece from the looper is regulated.

The spool has a diameter of 14"", which is also that of the periphery of the eye-piece. To facilitate the passage of the thread, the eye-piece is filed flat at the points, b and c; b, the section of which is shown, is the point at which the thread enters between the spool and the eye-piece, while c is the point at which the loop is detained by the drag, and drawn tight.

The eccentric, Fig. 15, attached to the main shaft, actuates by means of a connecting rod the lower end of the perpendicular arm of the needle lever. This arm is not, however, cast on to the lever axis, but so screwed on that it can be lengthened or shortened at will by means of a in. screw, t, Figs. 1, 2, and 3. The rise of the needle can be thus regulated, as also the space between the eye of the needle and the looper point, at the moment of the latter entering the loop of the upper thread.

The needle hole, Fig. 12, has a diameter of in., and is enlarged conically in a downward direction. It is the termination of the slot, ab, in. in breadth, by means of which the lower thread is conducted through the needle hole before commencing to sew.

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The two screw points, on which the needle lever works, serve to keep the needle true to the centre of the needle hole. The needle lever vibrates on the left side of the bracket head, and generally has the tension apparatus, gf, attached to its hinder end close to its fulcrum.

I.