US122256A - Improvement in presser-foot lifters for sewing-machines - Google Patents

Description

93' T W.-KENNEDY.

Improvement in Presser-Foot Lifter for Sewing Machines.

No. (22,256. PatentdDec. 26,1871.

UNITED STATES PATENT OFFICE' THEODORE W. KENNEDY, OF NEW YORK, N.

IMPROVEMENT IN PRESSER-FOOT LIFTERS FOR SEWlNG-MACHINES. i

Specification forming part of Letters Patent No. 122,256, dated December 26, 1871.

To all whom 'it may concern:

Be it known that I, THEODORE W. KENNEDY, of the city, county, and State of New York, have invented a new and useful Improvement in Presser-Foot Lifters and I do hereby decla-re that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawing formng part of this specification,

and in which- Fig. 3 is a similar View to Fig. 2, but showing an old style of presser-foot lifter, upon which my invention is an improvement.

Similar letters of reference indicate correspon ding parts.

This'invention generally relates to sewing-machines in which the presser-foot has an up-anddown motion in unison with the needle and timely relation to the feeder, as, for instanee, in the Grover and Baker elastic stitch sewing-machine, to which my improvement is particularly applicable. The 'presser-foot lifter of such machines, which is the device that my invention specially relates to, consists of a loose plate-like lever entered within a slot in the top of the presserarm or frame, and fittin g through a perforated a and slotted presser-foot, bar, orslide to provide for the self-adjustment of the presser-foot to different thicknesses of cloth, and, by thro wing back said lever, to hold the presser-foot up from contact with the fabric. Said lifters, however, as heretofore constructed, have been defective in the following respect, namely, they have been so formed or shaped that the presser-foot bar in rising and falling, and which sometimes equals i two hundred and fifty strokes'a minute, has produced a corresponding movement of the lifter, throwing itbaekward and forward each up-anddown movement of the presser-foot, thereby making considerable noise; besides, by its jumping motion in proximity to the work being very annoying to the operator. My improved lifter ob viates this defect by con structin g it with a straight face or edge that serves as a back to the presserfoot bar, whereby it is both motionless and noiseless so far esthe action of said bar upon it is concern ed. Said lifteris also provided with atootl or shoulder arranged to rest against the presserarm or frane to keep the lifter from pitching for ward when the presser-foot is lfted by work of suficient thickness to endanger such` action.

Refer'ing, in the first instance, to Fig. 3 of the drawing, A represents an ordinary presser-foot lifter as heretofore used on a Grover and Baker elastc stitch sewing-nachine, the same being formed with an open eye, b, for its fit over and clip of a liftin g partition, c, that divides an upper orifice, d, from the slot e in the slide or bar f of the presscr-foot B; said slot providing for theadjustment of the presser-foot to different thick- G is the 'presser-arm or frane i nesses of oloth. in a slot, g, at the top of which the lifter A is inserted, and so that on throwin g said lifter back till its rear edge Iz rests on the bottom of said slot or lies parallel therewith or thereabout, the presser-foot is lifted and kept raised by the lifter A from contact with the cloth. The front edge i of this lifter, against which the back of the bar f rests, is of a curved form, and the lifter generi ally of a shape so that every time the presserfoot rises and falls a corresponding movement or backward and forward motion is communicated to the lifter, 'as hereinbefore referred to.

This continuous movement and consequent rattle of the lifter is avoided by constructing it as represented in Figs. 1 and 2, in which" the lifter A' is formed with a straight front edge, 'i', at the back of the presser-foot bar f, of a length equal a to the full stroke of said bar, so that the presserfoot in rising and falling has no action upon the lifter,which remains' motionless and silent. Furthermore, said lifter is formed with a tooth or shoulder, k, arranged to rest against the presser-arm or frame G, and serving to keep the lifter from pitching forward and beconing detached or displaced when the thickness of the material under the presser foot causes the top of the slot e in the bar f to project above the upper outer end of the open eye b of the lifter. The straight edge i' and shoulder k combined make the lifter A' perfect in every respect, both as regards its retention in place and non-interference by the bar f in the working of the presser-foot. V

What is here claimed, and desired to besecured by Letters Patent, is-

1. The -presser-lifter A', constructed with an elongated straight edge, i", in front for operation n relaton With theback -of the presser foot bar tooth o r shoulder I fomed in Or on the preseror of thelatter relatively to it, s bstantially as f'ot' 'lifter A', ubstantially as'shown and despecfied. scribed.

2. The presser-foot lifter A', constructed with a tooth or shoulder, Ic, at its base in front for support of the lifter by the presser-ba' or frame O, witnesses: essent-ally as heren set forth. FRED. HAYNES, i

3. The combination of the straight edge i' and R. ERABEAU. 134:)

THEO. W. KENNEDY.

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