US34081A - Improvement in sewing-machines - Google Patents

Description

2 Sheets-Sheet l.

R. WELCH. SEWING MACHINEI No. 34,081. Patented Jan, 1862.

2 Sheets-Sheet 2.

R. WELCH. SEWING MACHINE.

No. 34.081, .Patented Jan. 7, 1862.V

Wnesses,

UNITED STATES PATENT OFFICE.

ROBERT WELCH, OF FRA-NKFORD, PENNSYLVANIA.

'IMPROVEMENT INy SEWINGvMACHINES.

Specilication forming pal-t of Letters Patent No. 34,08 l. dated Jarnlary T, 186') ,'lo all yzr/lo'm, 'it may concern.-

Be it known that I, ROBERT WELCH, of Frankford, in the county ot' Philadelphia and State ot' Pennsylvania, have invented a new and useful Improvementin Seiviiig-lllacliines; and l do hereby declare that the following is a full, clear, and exact description of the same, reference being had totheaccompanying drawings, forming part of this specilication, in which- Figure lis an elevation of that end of a sewingmacl1ine farthest from the needle, Fig. 2 is a vertical section of the machine at right angles to Fig. l.

`Similar letters of reference indicate corresponding parts in both figures.

My invention relates to the use of a threadfceding apparatus for feeding the thread to the performing-needle, so combined with the clothfeeding apparatus that the quantity of thread supplied foreach stitch will always be in proportion to or will correspond with the length 0f that stitch; and the invention particularly consists in a device, hereinafter described, which adapts the improvement to various descriptions of feed in common use and admits of ready adjustment to suit various thicknesses of material being sewed.

To enable those skilled in the art' to make and use my invention, I will proceed to describe its construction and operation.

A is the bed of the machine. B is the stationary arm, U lthe presser, D the needlebar, and E tle needle-operating lever, all constructet. and applied as in many other Wellknown sewing-machines.

F is the main shaft, and Gr the shaft of the cloth-feed wheel H, arranged parallel with each other in bearings below the bed-plate, the main shaft carrying a needle operating` cam, I, a shuttle-operating cam, J, and a cranlror eccentric wrist, a, for producing.,r Vthe feed move ment, and the feed-shaft carrying, besides the feed-wheel, a pulley, K.

L is-a shaft arranged between centers in standards b b, above the bed A, in a position Vparallel with the main and feed shafts for the purpose of carrying a cone, M, having severall grooves, c c, running round its periphery, the said cone being either made of the same piece of metal with the said shaft or being otherwise constructed a'nd secured lirmly to the shaft concentric therewith. This many grooved cone constitutes the principal portieri ofthe thread-feeding apparatus, as will be presently explained. 'lhe shaft L has also formed upon or secured to ita grooved pulley, r1,i'or the reception of a band, e, to run round it and round the pulley K of the feedshaft, and the said shaft L has also secured to it a ratchet-wheel,

f, and has tted loosely to ita lever, N, carrying a pawl, g, which works in the said ratchetwheel. rlhe lever N is connected by a rod, 0, with the crank-wrist a, from which, when. the machine is in operation, the said lever derives an oscillating movement snicient to carryits pawl over one or more teeth of the ratchetwheel, by which means it is made to impart to the shaft L and cone M au intermittent rotary motion, giving them one movement for every operation .of the needle and shuttle, and the shaft L, by means of the pulley d, band e, and pulley K, is made to impart a lcorresponding movement to vthe feed-shaft for the purpose ot feeding the cloth. lt is a slot provided in the lever N for shifting the connection `of' the rod O to vary `the feed.

P is a movable tightening-pulley for tight ening the band e. A pair ofspurgears may be substituted for the bande and pulleys d and K, and in that case it will be desirable to arrange the shaft L nearer to the feed-shaft than is represented in the drawings.

The spool R, carrying the needle .thread, may be arranged in any convenient relation to the cone M for the thread to pass once or more times round the said'cone, in one of the grooves thereof, on its way to the needle n. I have represented the said spool as placed upon a pin, i, secured in the table of the machine. The thread is directed from the said cone to the needle n by guidesj 7c l, arranged in any suit-l able manner, according to the -form and construction of the machine. The thread is represented in red color.

The thread in passing round the cone Ml is subject to such a. degree of friction that it will not slip thereon under any ot' the ordinary circumstances of the operation ot the machine, but will be drawn oli` the spool and fed toward the needle in every movement ot' the said cone produced by the action of the wrist a, rod O, lever N, pawl g, and ratchet-wheelf, as hereinbel'ore described, the quantity thus drawn from the spool being greater or less, according as the movement of the pawl g is greater or less. The said quantity must always correspond with the feed movement of the cloth, for' the shaft G of the cloth-feed wheel is driven by the shaft L of the cone M, and as no thread passes the cone except While thevfeed takes place, the tension of the needlefthread in the several stitches must be uniform if the thickness of the cloth is uniform. y The thread-feed and the cloth feed operating simultaneously causes the quantity to be regulatedfcr every separate stitch, so that if the cloth-feed is altered the thread-feed is altered to accommo-v date the very first stitch made after the alteration.A `In case ot' a sudden increase of the thickness of the cloth, as in the crossing of a seam, the thread will slip on the cone. The several grooves in the cone are to adapt the operation to diierent thicknesses of cloth, rnorelor lessthread being fed, accordingr as it passes round a larger or smaller portion ofthe cone. In a machine which would; always be required to, sew the same thickness of cloth a simple groovedor plain cylindrical roller may be used in place of and would be equivalent to a cone with many grooves.

will remark that, though the sewing-niachine represented is a shuttle-machine, my invention is not limited in its application to that class of machines, but may be used in all kinds of sewing-machines. What I claim as my inventiomand desire to secure by Letters Patent, is-

1. Feeding the thread to the needle of the .sewing-machine by means of a shaft, L, ro-

Images