US116893A - ceaig - Google Patents

Description

UNITED STATES PATENT GFEICE.

SIDNEY S. TURNER, or wESTB'oEoUGH, AND ISAAC s. CRAIG, or DoSToN, MASSACHUSETTS, ASSIGNCES To I. S. CRAIG.

IMPROVEMENT IN SEWING-MACHINES;

Specification forming part of Letters Patent No. 116,893, dated July ll, 187]..

To 4all whom it may concern:

Be it known that we, SIDNEY S. TURNER,

of Westborough, in the county of Vorcester, and n ISAAC S. CRAIG, of Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Sewing- Machines; and we do hereby declare that the following is a full andfexact description thereof, reference being had to the accompanying drawings and to the letters of reference marked thereon.

The nature of our invention consists: lst, in combining, with the sewing mechanism of a sewing-machine, an auxiliary take-up and devices for operating the same, which, acting upon that portion of the thread which is between the needle and the previous stitch, takes up acertain desired length of the thread, so that when the hooked needle takes the thread it contracts with the said thread at a point which will form, when drawn through the stock, the lower end of the loop, so that the thread does not slip through the hook and thus be chafed, worn, or cut, as

. would be the case if the loop had not been previconstruction and use.

Inthe drawings, Figure lis a perspective view, showing our improvement. Fig. 2 is a plan7 showing the thread-carrier, auxiliary take-up, and pressure-foot. Fig. 3 is a plan, showing the actuating devices. Fig. 4 is a sketch, showing the lower end of the pressure-foot with the threadguard attached.`

In Fig. l, A represents the table of the machine, and A the arm to which the parts are attached. B is the pressure-bar, to the lower end of which the pressure-foot E is attached. M is an arm connected to the bar B by the screw-nut B and so arranged that when the shaft L oscillates -in the direction indicated by the arrow the cam m will strike Ythe lower end of this arm and thus raise it, together with the bar B, but when L oscillates in the opposite direction the cam m, will have no effect upon the arm M except to push it to swing it back. H iS a plate attached to the ba-r B, and extending, as shown, into the annular grooves made in the thread-carrier bar D and in the auxiliaryv take-up bar C, so that when the pressure-foot is raised D and G will also be raised. S is a spring, which serves to keep the pressure-foot down upon the work. L is a wheel attached to the oscillating shalt L, and carries on its periphery the arm L, which serves as an ordinary take-up, and the cam O which serves to operate the bar K K.

The operation of this bar K is best represented in Fig. 3. The head ofthe bar C is provided with teeth, as represented, which mesh into corresponding' teeth made in the bar K so that any longitudinal motion given to the bar K will cause C to revolve on its axis. rlhe bar D is provided with a crankfarin, D', and is connected, by means of a crank-pin, p, and the arm D, to the vibrating bar K, so that a revolving' motion will also be communicated to D by a longitudinal motion of the bar K.

O is a cam attached to the periphery of the oscillating wheel L, and is so arranged, in connection with the vibrating bar K and the pin k, that when it passes in the direction indicated by the arrow onL it will throw the bar K K forward, the spring-S S serving to throw the bar back. The part K of the vibrating bar is free to slip back, leaving the part K unmoved; this is so made to" admit of the return of the 'cani O in front of the peg 7c, as represented by the red lines in Fig 3. f, Figs. 2 and 4, represents a guard attached to the pressure-toot, and serves to prevent the loop which is formed by the auxiliary take-up C and carried under the guard from flying back a-nd getting entangled with the awl.

Our invention has for its primary object the avoiding of abrasion and ultimate breaking of the thread. The thread, as it is being drawn down through the stock, slips in the barb of the needle, and is thus worn or frayed more and more at each movement of the needle until it finally breaks; and, to avoid this, the auxiliary take-up C is arranged and operated in such a manner that it takes the thread held by the thread-carrier D a little way off from the needle so as to measure off a suthcient length to form a loop for the shuttle before the barb of the needle takes hold of the thread, the parts being so adjusted that the barb takes the thread at that point which forms the 'lhe auxiliary take-up C and its operating` devices, all constructed, arranged, and operating substantially as described and shown, for the purpose of measuring off sufcient thread to form a loop for the shuttle, and preventing the Winding of the thread by the impact of the hook, as set forth.

S. S. TURNER. I. S. CRAIG.

Witnesses:

FRANK G. PARKER, CHAs. J. BATEMAN.

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