US146505A - Improvement in sewing-machines - Google Patents

Description

Nrrnn STATE-s WILLIAM e. BECKWITH, or NEWARK, NEW JEEsEY.

IMPRovEMENT |N SEWING-MACHINES.

Specification forming part of Letters Patent No. 146,505, dated January 20, 1874 ;i application filed December 31, 1873.

To all whom it may concern:

Be it known that I, WILLIAM GoULD BECK- WITH, of Newark, in the county of Essex and State of New Jersey, have invented certain Improvements in Sewing-Machines, of which the following is a specification:

My invention relates to the mechanism for feeding the material sewed through sewingmachines; and consists in a novel construetion, combination, and arrangement of parts, which have for their object to improve the operation of the nachine, and afford an easy and accurate means of regulating the length'of the stitch, as will be fully hereafter described.

Figure 1 is a side view of the upper extremitymof the needle-arm of a sewing-machine similar to the one shown and described in Letters Patent No. 133,351, granted to me November 26, 187 2, with my improvements attached. Fig. 2 is a reverse view of Fig. 1. Fig. 3 is a diagram illustrating the operation of the stitchregulating mechanism; and Fig. 4 is a section through theline y y, Fig. 1.

A represents the needle-arm of the machine, which receives reciprocating motion by the means described in the Letters` Patent No. 133,351, or any other desired way. 0nA the forward end of this arm is formed a plate, B, on

which plate, at right angles to its outer surface, is cast the flange C. The needle is rigidly `secured to the block D, as described in the above-mentioned patent and shown in Fig. 4 of the drawings accompanying this specification. On the rear side of the plate B, and at its lower extremity, is pivoted the lever E, which is formed into a plate, e, at its lower end. The pin b, rigidly secured to the block D, passes A through a slot in the plate B, and through a hole in the lever-plate e, in which it oseillates, and is retained by the thumb-screw cl; and as the lever E is moved back and forth the block D receives a similar motion, the slot in the plate B allowing the play of the pin b. In the upper part of the lever-plate c is cut a slot, c, through which a screw passes, the purpose of which is to create friction on the lever E to retain it in any desired position. From the upper part ofthe block D projects a pin, a, which serves to keep the spring f, which presses against the rib or flange C on theplate B, in position. F is a screw passing through the lower extremity of the ange C, and against which the spring f has a `tendency to keep the bar D. g is a spring for creating friction on the screw F to prevent itsturnin g'accidentally. The cloth is held on the plate G by a `presserfoot, which is niched or barbed, as shown.

The needle IL, as in my former patents, is tangent to the arc described by the needlearm, or by the point of the needle, and thus, in passing through the cloth, it carries it forward the length of the difference between the radius of the point of the needle and that of the point on the needle at which it (the needle) stops or ceases to be tangent to the arc described by the needle-arm, and, as the needle necessarily performs the same path in ascending as in descending, it would return the cloth from where it withdrew'it 5 but this is obviated by slightly niching or roughenin g the presserfoot to prevent the returnof the cloth, and the needle, in ascending, would cause the cloth to pucker in front of it if it (the needle) were rigidly ixed to the needle-arm; butas `it is pivoted to the lever E through the block D, so as to be capable of receiving an oscillating motion in its ascent, the thread tightens, and, exerting a pull on` the needle, slightly turns it, (the needle,) the spring readily yielding to the pull` of the thread, and thus the needle is withdrawn from the cloth without puckering it or having any tendency to push it backward. As the needle commences to descend the thread slackens, and the spring forces the bar D out and moves the point of the needle some distance over the surface of the cloth prepara-tory to its descending for another stitch.

In my former patent, N o. 133,351, the block D was pivoted directly to the plateB, and the stitch was regulated by the screw, which acted on the lower 'end of the block to throw the needle in or out over the cloth, and thus shorten or lengthen the stitch. This manner of regulating the stitch was imperfect, as the needle entered at a different `point in the cloth-plate each time the stitch was altered, and thus its relation to the looper was changed, making the stitch irregular and uncertain. Thisinvention obviates this difficulty, as, instead of Ichanging the point of the needle, I shift the pivot on which it turns by means of the lever E, in which lever the pivot-pin b has its bear- PA'IENT OFFICE. `N

ings, as before described, and thus either shorten or lengthen the chord of the arc de,- scribed by the needle-point, and changing the angle of the needle. This will be readily understood by referring to the diagram, Fig. 3, in which the heavy line D represents the needle and needle-block pivotecl to the lever E at b, which lever is pivoted at fi to the plate B. The dotted arc j represents the slot in the plate B, in which slot the pin pivoting the block D 'to the plate-lever plays back and forth as the lever is operated. The line F F represents the screw, against which the needle-block is kept by the spring represented by the line ff. The arc 7c shows the lowest point to which the needle descends in the'cloth.

O11 desiring to shorten the stitch, the lever is drawn out, as shown by the dotted line E E. This .will bring the needle, which turns on the screw F as a fulcrum, to the position ofthe broken and dotted lines D2 h2; and, to bring the point of the needle to the point l, the screw must be retracted to the point m, when the needle will assume the position of the dotted line D1 hlrandthe stitch be shortened by the I difference between the two points n o. y

It will be observed that with this means of adjustment the stitch is shortened in the rear of the needle, while in my other patents, where the needle was thrown in by the screw, just the reverse was the case, the stitch being shortened from in front; and that, in this instance, the needle enters at the same point on each alteration.

I claim- 1. The stitch-regulating mechanism consisting of the lever E e, pivoted needle-block D, pin b, screw F, and spring f, constructed and operating substantially in the manner and for the purpose described. y

2. The combination, with a stitch forming and holding mechanism, of a stitch-regulating mechanism, constructed and operating substantially as described and specified.

VILLIAM G. BECKWITH,

Witnesses:

E. H. J oHNsoN, C. C. DURGIN.

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