US613537A - E norbis peters co - Google Patents

Description

No. 6l3,537. Patented Nov. I, I898. H. R. TRACY.

SEWING MACHINE.

(Application filed. Apr. 10, 1896. Renewed. Mar. 31, 1898.)

2 Sheets-Sheat I.

(No Model.)

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No. 68,537. Patented Nov. I, I898. H. R. TRACY.

SEWING MACHINE.

(Application filed Apr. 16, 1896. Renewed Mar. 31, 1898.) (No Model.) 2 Sheets-Sheet 2.

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HARRIET RUTH TRACY, OF NEWV YORK, N. Y.

SEWING-MACHINE.

SPECIFICATION forming part of Letters Patent No. 613,537, dated November 1, 1898.

Application filed April 10, 1896. Renewed March 31, 1898- Serial No- 676,008- [No model.)

To all whom it may concern.-

Be it known that I, HARRIET RUTH TRACY, a citizen of the United States, residing at New York, (New Brighton,) in the county of Richmond and State of New York, have invented certain new and useful Improvements in Sewing-Machines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

This invention relates to sewing-machines, and particularly to that class in which a loop of the needle-thread is engaged by a looptaker and carried around the latter to produce a loop to inclose a lower thread to form a lock-stitch.

In Letters Patent of the United States issued to me March 15, 1892, and numbered 471,035, I have shown and described a looptaker or shuttle having three loop-engaging hooks. In practical operation I find that a shuttle having this number of hooks will operate satisfactorily where thin or medium thick fabric is sewed; but where heavy thick cloth or other fabric is sewed I find that the loops of the needle-thread will not be drawn up tightly against the under side of the fabric, owing to the fact that the needle enters the fabric before the loop is properly taken up and binds or looks the thread in the needle-opening, resulting in the formation of a succession of loose stitches or loops depending from the under side of the fabric. If, to overcome this defect, the tension is increased, the result will be either that the thread will break orthat more thread will be drawn from the spool, the latter result tending to increase the size of these loose loops. The cause of this defect in the proper taking up of the loop of the needle-thread is due to the fact that the needle reciprocates too rapidly with relation to the rotation of the shuttle, or, in other words, the shuttle does not rotate a sufficient distance between the formation of the stitches to allow adequate time for the proper taking up of the successive stitches. It will be seen by reference to the patent of which mention has been made that the shuttle makes but two-thirds of a revolution to complete a stitch, so that the loop of the needle-thread does not have time to pass the vertical diameter of the shuttle before the needle again be= gins to descend to make a succeeding stitch, thereby leaving the loop on the shuttle in a relaxed condition when this succeeding stitch is begun, resulting in the formation of the loose stitches or loops on the under side of the cloth before referred to. It will be obvious if the needle is so timed with reference to the shuttle that the latter will have rotated sufficiently to take up the slack of the loop of the needle-thread before the needle enters the fabric to make a succeeding stitch and to draw su fficient thread from the upper spool to make the stitch in any thickness of cloth that the formation of the loose loops will be entirely overcome, whether the fabric be thick or thin.

To this end, therefore, my invention has for its object to effect the proper and complete taking up of the loop of the needle=thread before a succeeding stitch is formed.

With this object in view the invention con sists in the novel details of construction herein described and claimed.

In the accompanying drawings, forming a part of this specification, and in which like letters of reference indicate corresponding parts, I have illustrated a form of embodiment of my invention, although other forms of embodiment thereof may be employed without departing from the spirit of the same, and in the drawings- Figure 1 is a view in front elevation, showingasewing-machine embodying my improvements, portions being broken away more clearly to display certain parts. 4 view in end elevation,taken from the left hand of Fig. 1. Fig. 3 is a view in side elevation of a loop-taker constructed in accordance with my invention, showing a work-plate, a piece of cloth upon which sewing is to be done, and a needle arranged adjacent to the loop in proper operative position, the parts being shown in the position assumed after the first loop of the needle-thread is engaged by one of the hooks of the loop-taker. Fig. 4: is a View corresponding. to Fig. 3, the loop shown in Fig. 3 having been carried approximately three-fourths around the loop-taker, a second loop of the needle-thread being shown as engaged by the loop-taker, the needle having been drawn up through the cloth and the cloth fed to form a second loop; and Fig 5 is Fig. 2 is a a view corresponding to the previous figures, showing a completed stitch, the second about to be drawn up into the cloth, and the third loop shown as just engaged by the loop-taker.

Referring to the drawings, A designates the loop-taker, which is supported for operation adjacent to an ordinary eye-pointed reciprocating needle and receives motion through mechanism hereinafter described. The looptaker is shown in this instance as supported by rollers B, although it is to be understood that it may be supported by other means than that shown.

In the periphery of the loop-taker are formed four loop-engaging hooks, each comprising a too a, (L (L5, and a and aheel a a a, and 61,7, respectively, the toe being designed to engage the loop of the needle-thread as the same is broughtdown through the cloth and the work-plate of the machine and the heel to retain the loop until the same is carried around the loop-taker to inclose a lower or shuttle thread to form a lock-stitch. In order that each succeeding loop of the needle-thread may properly set each preceding loop or stitch, the loop-taker is so timed with relation to the needle that the former makes three-quarters of a revolution between two successive descents of the needle and a preceding loop of the needle-thread is substantially taken up before the needle enters the fabric to make a succeeding stitch. This timing of the needle with reference to the rotation of the loop-taker is of great value in that it allows ample time for the majority of each loop to be taken up before a succeeding loop is taken, the action of the loop-taker upon the latter setting the stitch by drawing up the residue of the preceding loop, thereby preventing the formation of loops or loose stitches on the under side of the fabric.

The mechanism for operating the loop-taker comprises a loop-taker driver 0, having arms 0 for engaging sockets in the back plate of the loop taker. This driver is operated by a shaft 1), which is driven from a vertical shaft E, the latter shaft being driven by the needle-bar-actuating shaft F through the mediu m of miter-gears e and f, carried by the needlebar-actuating shaft F and vertical shaft E, respectively. The lower end of this vertical shaft carries a miter-gear e adapted to engage a similar gear d on the shaft D, by which motion is imparted to the latter shaft. The

train of gears herein shown is so timed as to give to the needle two complete reciprocations to a single rotation of the loop-taker, or, in other words, the train has a timing that will establish a ratio of movement between the needle and the loop-taker as two to one.

The fabric-feeding mechanism is operated directly from the shaft E and may be of any suitable construction and organization and is here shown as consisting of a feed-dog supported in any suitable manner for reciprocation between the needle-bar and the looptaker, a feed-dog carrier or feed-lever G, pivotally carried for vertical and horizontal oscillations by a bracket 9 a link 9 connecting the feed-lever carrier and feed-dog and adapted for insuring a right-line movement to said feed-dogduring operation, and the feed-leveractuating cam g, in adjustable rotatable connection with the shaft E of the train of gears and in operative connection with the feedlever and adapted through the medium of the shaft E and its connections for imparting alternate vertical and horizontal oscillations to the feed-lever.

The needle-actuating shaft F is journaled at or near its opposite ends in suitable bearingsf in the arm 11 of the machine and is operatively connected with the needle-bar I by means of a crank f and a connecting-link or connecting-rod f after the usual manner of making crank connections between reciprocating parts.

The take-up J may be of any preferred construction and operates partially to draw up the loop of the needle-thread, the loose loop left in the formation of each stitch being taken up and set by the loop-taker in the making of a succeeding stitch.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is

The herein-described sewing-machine comprising a reciprocatory eye-pointed needle, a revoluble loop-taker having four loop-engaging hooks, and means for actuating the needle and the loop-taker to give to the former two complete reciprocations to a single rotation of the latter, and giving to each hook a threequarter revolution between two successive descents of the needle, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

HARRIET RUTH TRACY.

Witnesses:

E. H. PARRY, R. M. ELLIOTT.

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