US12577A - Improvement in sewing-machines - Google Patents

Description

T. J. w. ROBERTSON.

5 W Sewing Macihne. No. 12,577. Patented March 20, I855.

N. PKTERS, Phowlimognphw, Washinginn. D. C-

g V v UNITED r STATES,

PATENT OFFIQE.

v r. J. w; nonnarson, on NEW. YORK, N. Y.,' Assionoa 'ro HIMSELF AND A. E. BEACH. I

iMPROVEMENT |N SEWING-MACHINES.

Specificationforming part of Letters Patent No. 2,577, dated March 20, 1855.

' To all whom it may concern:

Be it known that ;I, T. J. W. ROBERTSON, of the city, county, and State of New York, have invented a new anduseful Improvement in the Feed-Motion of Sewing-Machines; and I do hereby declare that the following is a a full, clear, and exact description of the same, a reference being had to the accompanying drawingsyforming part of this specification, in which- Figure 1 is a front view of a portion of a sewing-machine with inyimproved feed-motion applied. Fig. 2 is a plan of the same. Similar letters of reference indicate corresponding parts in both figures.

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

A. in the accompanying drawings is the cloth-table. B is the needle-slider, and O O the slide in which the said slider works. These parts. are all arranged in the same way as the corresponding parts of manywell-known sewing-machines.

D is a spring of the form I propose gener;

ally to employ to confine the cloth to the table. This spring consists of a curved bar of steel attached to theside of the slider O O, or other fixed portion of the machine, and terminating with a broad shoe, E, to bear upon the mate-. rial to be sewed all round the needle, the latter being intended to workthrough the opening a, (see Fig. 2,) made in the shoe for the purpose. Another hole, I), is also .made in the shoe for the feedingdog to work through. The blue line in Fig. 1 represents the material confined to the table by the spring.

f is the feeding-dog, consisting of a piece of steel or other metal having a serrated face, and being attached rigidly to or forming part of a light bar, F, which is suspended from the arm c of a three-armed lever whose fulcrum is a pin, d,which may be either secured in the upper part of the spring D, as represented, or in I some other convenient fixed part of the machine. If the said bar is attached'to the spring D, all the elasticity should be belowthe point of such attachment. The dog worksthrough the opening bin the shoe E, which should be At about as near as possible to the needle. the middle of its length the bed-bar F works within aforked guide, 6, attached to the spring D, and near this guide an adjusting'screw, 9,

(see Fig. 1,) is fitted to the spring D, (which will be pushed aside during the ascent of the needle and the latter during the descent of the needle by a wiper. j, attached to the needle-slider B. The effect of the latter movement is to raise the arm 0, to which the feedbar is attached, and of the former to depress the said arm.

I will now describe the feeding operation,

first supposing the dog to be raised from the surface of thecloth and hanging against the screw 9, as indicatedin red outline in Fig.

l. I will now suppose the needle-slider and the wiper to be rising from the cloth, by which action the wiper j will push aside the arm h of the three-armed lever tothe position in which it is shown in black outline, and in so doing will depress the arm 0. The feed-bar F, during the above operation, will slide along the point of the screw 9 until the dog f bears upon the cloth, after which the dog will be caused to slide the cloth along the table in the direction of the arrow. WVhen the needleslider and wiper j descend, the wiper in pushing aside the arm t will raise the arm 0, and, as the dog is by that means withdrawn from contact with the cloth, the feed-bar will fall back to the screw g.

The screw 9 serves to regulate the length of stitch by controlling the backward movement of the dog; or the length of stitch may be varied by moving the wiper farther in or out to move the dog farther or not so far forward.

In applying the feed-bar care must be taken ing the perpendicular to prevent the dog slid ing easily. I consider an angle of about twenty degrees to be well adapted for the purpose.

In order to prevent a reaction being produced on the dog by any elasticity of the cloth or material being sewed, after the wiperj passes the arm 7 in its upward motion, I attach a spring, k, to the fixed part of the machine, so as to produce friction upon the pin 8, by which I the feed-bar is connected to the arm c of the three-armed lever, or apply some equivalent device to produce sufficient friction on the said pin to prevent the dog being returned by such means.

I have only represented a single toothed feeding-dog5 but I propose to use two united in the form of a fork, one working on one side and the other on the other side of the needle,

which will work within the fork.

Most of the feed-motions now in common use, with a spring to hold or confine the mamotions the dog is arranged under the table and acts against the spring or plate E. If there is any extra resistance to the feeding of the cloth, the spring or shoe is apt to give or rise, and consequently the dog will not act properly upon the cloth. By arranging the dog on the upper side of the cloth, so that it will act against a rigid plate or table, this (10- feet is avoided, and the advantage of the yielding pressure of the springE upon the cloth is retained. There is another advantage in arranging the feeding-dog on the upper side of the table. It gives room and opportunity for forming a forked dog, so that'the needle may work between the forks of the dog, instead of on one side, as heretofore.

I do not claim in itself as new the arrangement of the feeding-dog and spring-clamp separately operating upon the cloth on its one or outside surface, as such. has before been done by the alternate action of these devices. Neither do I claim of itself a separate and constant spring-pressure applied to the outside surface of the cloth when the feeding bar or dog is otherwise arranged to operate in connection with the spring clamp or hold, as specified; but

I do claim as new and useful and desire to Secure by Letters Patent The combination of the spring-clamp D with the feeding bar or dog f, constructed, arranged, and operating together against the cloth on its one side or surface substantially as set forth.

T. J. W. ROBERTSON.

\Vi tnesses WM. DIXEY, A. E. BEACH,

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