US431957A - Stitch-breaking and raveling attachment for machines for sewing looped fabrics - Google Patents

Description

Patented July 8,1890,

A. L. TRAVER. STITCH BREAKING AND RAVELING ATTACHMENT POR MACHINES FOR SEWING LOOIED FABRICS.

(No Model.)

IVE/#T0117` .Adalbert LEE Travel' 'NVZ/@QM ATTORNEY' UNITED STATES I PATENT OFFICE.

ADELBERT LEE TRAVER, OF PIIILMONT, NETV YORK.

STITCH-BREAKING AND RAVELING ATTACHMENT FOR MACHINES FOR SEWING LOOPED FABRICS.

SPECIFICATION forming part of Letters Patent No. 431,957, dated July 8, 1890. Application tiled September 27, 1889. Serial No. 325,272. (No model.)

To LZZ whom 2175 may concern,

Be it known that I, ADELBERT LEE TRAVER, a citizen of the United States, and aresident of Ihilmon t, Columbia county, State of New York, have invented new and useful Improve ments in Stitch -Breaking and Raveling Attachments for Machines for Sewing Iiooped Fabrics, ot' which the following is a specification.

The purpose of my invention is to provide an attachment that may be applied to machines for sewing looped fabric of the class known as turning-.off machines, that will derive its motion from the main shaft of the sewing mechanism, and by a process of stitchbreaking and raveling level to a uniform height and prepare the edges of the fabric to be united after they are impaled upon the pin-plate and are being carried by it to the sewing mechanism. Y

Referring to the drawings, Figure 1 is a top view of my invention, together with a portion of the turning-off machine. Fig. 2 is a section through the line X X, Fig. 1, showing the means for removing the raveled and separated portions of the fabric. Fig. 3 is a section through the line Y Y, Fig. 1, showing the stitch breaking and raveling, mechanism. Fig. et is a section through the line Z Z, Fig. 1, looking in the direction of the arrow a. Fig. 5 shows in perspective view the parts directly concerned in stitch-breaking and raveling, and Fig. G shows in perspective view the parts directly concerned in the removal of the raveled and separated portions of the fabric.

A machine for sewing looped fabric of the class of turning-off machines to which my attachment is applicable consists of the two following elements: first, a` pin-plate 1, Figs. 1 and 2, having on its periphery 4pins that carry the edges 2 and 3, Fig. 2, of the fabric to be united; second, a sewing-machine a, of which 5 is its main shaft, and 6 is its sewingneedle.

The main frame 7 of my attachment is secured to any fixed part of the turning-off machine where the operative parts may be brought in the proper posit-ion to act on the fabric carried by the pin-plate.

In- Figs. 1 and-2 the main frame of my attachment is shown connected to the turningoff machine through the sliding joint 8 and the anglepiece 9. To effect adjustment on this joint, a stud rigid to the frame passes through a slot in this angle-piece and is threaded for a clamping-nut. A thumb-nut 10 passes through the angle-piece and taps into the stud, whereby the frame may be drawn upward and its height above the pinplatethereby accurately adjusted. The preparation of the edges of the fabric for sewing involves two distinct operations. The first is illustrated in Figs. 3 and 5. The fabric impaled on the pin-plate, with its edges project ing more or less above the pins, is to be trimmed to a uniform height. For this purpose it passes between a wedge-shaped piece 13 and a guide 14C. The wedge has two vertical and parallel sides, a horizontal lower and an inclined upper edge. These edges are blunt or rounded, so as not to cut the fabric immediately on coming in contact with it, and it is intended that they shall not be of a shape that will co-operate in the manner of a shear with the edges of the opening in the guide on the opposite side of the fabric. The lower edge is horizontal, as is also the direction of motion with which the wedge is pushed into the fabric, so that this edge may lie close to and parallel with the pins on the pin-plate and serve to hold the fabric down onthe pins against the upward straining action of the inclined edge.

The function of the guide-plate 14, with its slot for the passage of the wedge 13, is to support the fabric while it is being entered by said wedge. In order to properly afford this support, the slot is made narrow, so that itwill be closed on the sides by the parallel sides of the wedge. By introducingthis construction I am enabled to dispense with a.

second wedge entering from the opposite side of the fabric and its complementary actuating mechanism, as illustrated in Patent No. 410,720, dated September 10, 1889, issued to me, and effect the severing of the fabric with fewer parts and in a more satisfactory manner. The action of the wedge on entering a loop of the fabric is to enlarge it until it breaks if both ends of the thread forming the loop are fast in the fabric, and to ravel it if IOO either end has been freed by the breaking of an adjoining loop. By thus avoiding a shearing orcutting action the fabric is raveled apart Wherever possible and no shortpieces of thread produced that will clog the machine. The second operation performed by my attachment is for the removal of the raveled and loosened portions of the fabric. After having been acted on by the wedge, as described, the edge of the fabric, in being carried by the pin-plate to the sewing mechanism, passes in front of the jaw 16. The jaw is carried forward till it grips the loosened edges of the fabric against the smooth surface of the guide-plate 14 in the positionin Figs. 2 and 6. Then it rises, carrying the fabric with it, draws away from the plate, and returns to its first position. For the purpose of conveying motion from the sewing mechanism to the above elements, universal joints and connections 17, 18, and 19 communicate motion from the sewing-machine shaft to the cams 2O and 21. These are four-motion cams identical in form, so that one may be considered as a continuation of the cam-surface of the other. They operate on bar 23 and a lever 22, mounted so as to slide and rock on the stud 24. The cam-surfaces on the lever 22 form a square. The cam in its revolution presses successively against these surfaces, so as to impart to the lever a motion iirst toward the fabric to the position shown in Fig. 2, neXt upward, then backward, and downward to the point of starting. Two of the camsurfaces in the bar 22 correspond with those on the lever 22 but on account of the yoke for the cam being elongated this bar 23 receives no oscillating motion upward and downward,- but onlya reciprocating one backward and forward from the cam. A stud 25, fast in the lever 22, plays in a slot 26 in the bar 23, with the upward and downward movement of the former lever. This stud'may be clamped rigidly in the slot, and the bar thus made fast to the lever, so that the two become as one lever operated upon by one four-motion cam. In practice I construct my attachment on this latter plan, with a single lever and cam, as there are then less parts, and the vertical movement imparted to the wedge, though not essential, is not objectionable. For the purpose of broadening my patent I have, however, shown and described the wedge 13 as separately mounted with the bar 23 from the jaw 16, and shown thata simple reciprocating motion is sufficient to enable it to perform its function. The wedge 13 is detachable from the bar 23 for the convenience of renewal. The jaw 16, however, is not rigid with the lever 22, but supported so that it can yield against the spring 27, according to the thickness of the fabric that may lie between this jaw and the guide-plate 14. I iind in practice that a second guide 29 on the same side of the fabric as the wedge 13 and jaw 1G contributes to the successful operation of the machine by guiding the fabric and preventing the accumulation of loose threads on the operating parts.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- 1. A fabric stitch-breaking and raveling attachment combining with the pin-plate of a turning-olf machine a bar having a wedgeshaped end consisting of two parallel sides,a lower edge lying close to and parallel with the pins on said pin-plate, and an inclined upper edge of sufcient length and inclination to give to the wedge-shaped part near its rear end sufficient dimension to draw out or break the loops of the fabric, a guide-plate lying against and supporting the opposite side of said fabric from said bar and wedge and having a slot opposite said wedge, mechanism whereby said bar may be reciprocated in the direction of the lower edge of its wedge-shaped end through said slot in said guideplate,and a frame for supporting and guiding said bar, for supporting said guide-plate and carrying said mechanism, substantially as and for the purpose set forth.

2. A fabric stitch-breaking and raveling attachment combining' with the pin-plate of a turning-olf machine a bar having a wedgeshaped end consisting of two parallel sides,a lower edge lying close to and parallel with the pins on said pin-plate, and an inclined upper edge, a guide-plate having a slot of such width as to just admit said wedge-shaped end and lying against and supporting the opposite side of the fabric carried by said piuplate from said Wedge-shaped end and with its slot opposite thereto, a four-motion cam for imparting motion to said bar by acting upon surfaces thereof at right angles to each other, mechanism for revolving said cam, and a frame for supporting and guiding said bar, for supporting said guide-plate and carrying said mechanism, substantially as and for the purpose set forth.

3. A fabric stitch-breaking and raveling attachment combining with the pin-plate of a turning-off machine a lever bearing a wedgeshaped end forsevering the fabric and a jaw where it can operate on the fabric between said wedge and the sewing mechanism, a guide-plate lying against and supporting the opposite side of said fabric from said wedge and jaw, a slot in said guide-plate opposite said wedge, a cam acting on this lever to slide it toward the fabric and then rock the end bearing the wedge and jaw upward from the pin-plate, mechanism for revolving said cam, and a frame for supporting and guiding said lever, for supporting said guide-plate and carrying said mechanism, substantially as and for the purpose set forth.

ADELBERT LEE TRAVER. lVitnesses:

SAMUEL L. MILLER, D. B. DowNINe.

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