US427026A - Thread-controlling device for sewing-machines - Google Patents

Description

[ i (No Model.)-

R. G. WOODWARD. Y THREAD CONTROLLING DEVICE FOR SEWING MACHINES.

No. 427,026. Patented Apr. 29, 1890.

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RUSSEL G. IVCODIVARD, OF IVAUKEGAN, ASSIGNOR TO THE UNION SPECIAL SEW'ING MACHINE COMPANY, OF CHICAGO, ILLINOIS.

THREAD-CONTROLLING DEVICE FOR SEWING-MACHINES.

SPECIFICATION forming part of Letters Patent No. 427,026, dated April 29, 1890.

Application filed March 30, 1889. Serial No. 305,362. (No model.)

To aZZ whom, it may concern.-

Be it known that 1, Russian G. W OODWARD, of \Vaukegan, county of Lake, State of Illinois, have invented an Improvement in Take- Up for Sewing-Machines, of which the followin g description, in connection with the accompanying drawings, is a specification, like letters on the drawings representing like parts.

This invention has for its object to provide a sewing-machine with a thread-controller which shall have its position varied automaticallyto provide for variations in thickness of the cloth or other material under the presserfoot, and thus give to the needle and stitchforming devices sufficient slack thread to accord with the thickness of the material.

In this invention the presser-bar has an attached rack which rises and falls in unison with it, the teeth of the said rack engaging with teeth at the end of a thread-controlling lever, having a long arm which is extended from its fulcrum backwardly toward the tension device, where it is provided withan eye to receive the thread.

To make the thread-controlling lever light, so that but little power is required to move it, the said lever has been constructed of a plate and a wire.

My invention consists, essentially, in the combination, with the work-support, presserfoot, presser-bar, and rack attached thereto and rising and falling with the presser-ba1',ot a thread-controlling lever having teeth at one end and an eye at the other end, and it being adapted to act upon the thread on its way to the eye of the needle and cause more slack thread to be given to the needle as the thickness of the material under the presser-foot varies, and vice versa.

Figure l in side elevation represents a suificient portion of a sewing-machine to enable my invention to be understood, the needle-bar being partially broken out to show the presserbar and rack attached thereto behind it, the thread-controlling lever being shown by clotted lines in the position it would occupy if the thickness of the material should be increased, as shown by dotted lines under the presser-foot; and Fig. 2 is a detail to be referred to.

The bed-plate A, the overhanging arm A,

containing the usual bearings for the needle and presser bars, the needle-actuating arm B, the link B, connected to a block secured to the needle-bar B are partially broken out in Fig. 1. The said needle-bar and the presserbar C and presser-foot C are and may be all of usual construction. The presser-bar C has applied to it the collarC ,forming part of the rack C, having teeth 2, the said hub having a projection c, the collar being held in adjusted position on the presser-bar by a setscrew 0. The pin or projection c is in practice acted upon by a suitable strong spring 0 attached at its opposite end to the overhanging arm A, the said spring normally acting to keep the presser-foot down upon the material under it. The spring 0 is of common use in sewing-machines.

The overhanging arm A has a stud-screw D, which constitutes the fulcrum for the thread-controlling lever D,havin g at one end a series of teeth 3, to be engaged by the teeth 2 of the rack C, which, as described, is connected to and rises and falls in unison with the presser-bar, according to the thickness of the material under the presser-foot.

The lever D, to make it light and yet sufficientlysti'ff, has a part of it composed of wire, as at 4, the said wire being bent at its outer end to form a socket for the reception of a stud-screw 5, to secure to the end of the threadcontroller the eye (3, through which the needlethread 15 is passed after leaving the usual tension device it, the said needle-thread being represented as carried through an ordinary loop or eye Z) at the upper end of the needlebar, and thence through the eye of the usual eye-pointed needle.

The tension device may and in practice will 0 be substantially the same as in United States Patent No. 3%,493, dated June 29, 1886.

In operation, as the material varies in thickness-say, for instance, as the material increases in thickness-the presser-foot rises 5 and causes the eye 6 to descend, as represented by dotted lines, and effect the production of more slack in the needlethread, so that when the needle descends more slack will be given up to the formation of the stitch than I00 when the material under the presser-foot is thinner. By extending the lever D well back 5 as described.

toward the tension device a slight movement of the resser-bar gives considerable movement to the lever between the tension device and its point of support on the needlebar.

I claim- 1. The COIllbli ;LLlOil,\\lilll the work-sn1r)port, needle bar, presser foot, presser bar, rackplate connected to and rising and falling with the resser-bar, and a tension device, of the pivoted threadcontrolling lever having teeth engaged by the said rack and extended horizontallytoward the tension device and acting on the needle-thread between the tension device and needle-bar, to operate substantially 2. The n'esser-har, its attached toothed

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