US313801A - Mechanism for making zigzag or irregular stitches - Google Patents

Description

(No Model.)

J. BIGEL'OW. MECHANISM FOR" MAKING ZIGZAG 0R IRREGULAR STITUHES. No. 313,801. Patented Mar. 10,1885.

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NITED STATES PATENT tries.

JOHN BIGELOW, OF PHILADELPHIA, PENNSYLVANIA.

MECHANISM FOR MAKING ZIGZAG OR lRREGULAR STlTCl-lES.

SPECIFICATION forming part of Letters Patent No. 313,80 1, dated March 10, 1885..

Application filed April 19, 1882. (No model.)

To all whom it may concern.-

Be it known that 1, JOHN BIGELOW, a citizen of the United States, residing at Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvementsin 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, reference being had to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this specification.

This invention relates to mechanism for making zigzag or irregular stitches with a sewing-machine and mechanism therefor, and more particularly for reciprocating a small tongue between the presser-foot and the workplate of the machine just in advance of the needle. The material to be sewed is fed over the tongue, between it and the under side of the presser-foot. The tongue, contrary to all other similar mechanism,is reciprocated when the needle is down in and through the work, instead of when the feed is taking place. This allows of half of the revolution of the drivingshaft of the sewing-machine during which to make the tongue movement or reciprocation, consequently my mechanism is capable of high speed. When the needle is in the work, the feed-dog has dropped below the level of the plate. It is at this time the tongue reciprocates. The tongue reciprocates to the right or left just in front of the needle, consequently draws a light flexible material, like knit fabrics, with it, and piles it to the right or left side of the needle. The feed,rising, takes the material thus piled up and moves it forward. When the needle descends, it'will be found not to pass through the fabric in the true line of straight-ahead sewing, but a little to the right or left of its former place in the material, according as the preceding movement of the tongue had been to the right or left.

In the Gritzner Patent N 0. 76,323, April 7,. 1867, and the several patents granted to my self, July 19,1881, for obtaining a zigzag stitch by reciprocating a tongue, the tongue extends beyond the point of penetration by the needle, and its movements extend to the right and left of the needle-line, and occur when the needle is out of the work and the feed is taking place, all of which is quite different from my present mechanism.

In order that my invention and the manner of carrying the same into effect may be fully understood, the same will now be described in connection with the accompanying drawings, in which Figure 1 is a plan view of the bed-plate of a sewing-machine, showing the position of the needle, tongue, feed, and resser-foot. Fig. 2 is a plan view of the under side of the bedplate of a sewing-machine, showing the mechanism by which I actuate my tongue piece. Fig. 3 is a detail view of the needle, presserfoot, feed, tongue piece, and its connection with its actuating device.

I do not show any special sewing mechanism, since any can be used, particularly the new stitch-forming mechanism, for which I have filed herewith an application for Letters Patent.

0, Fig. 1, shows the position of the neck of the machine on the bed-plate A, and D the driving-shaft, which conveys from the main driving-shaft motion to my mechanism.

V, Figs. 1 and 3, shows the position of the prcsser-bar; V, the presserfoot; T, the needle-bar; T. the needle-clamp; E, the feed; H, the needle; S, the tongue, which I have added, and S its connection with the actuating devicenR. 8 5

It will be noticed that the presser-foot at V, Fig. 8, is raised above the feed-surface on the under side nearly as far back as the needlehole in it to allow space for the tongue S, Fig. 1, and to obviate the necessity of raising the foot so much as to prevent the proper action of the feed. The tongue S does not quite reach to the needle-line T, Fig. 1, and vibrates from the position in which it is shown, and is its nearest approach to the feed E away from the same.

The tongue S receives its movements from the cam L, Fig. 2, with which it has a working connection through the yoke N, bar 0, Fig. 2, screw P, block 1?, plate R, and piece S. The cam L, Fig. 2, is attached to the gear K, which gear revolves on the stud M in the bed-plate B, and is in mesh with a smaller gear, J, on the driving-shaft D. The

gear K has twice as many teeth as the gear J, therefore revolves only half as fast. The cam L is of the well known triangular form, adapted to be always in contact with its yoke in the direction of the movement required. As arranged, italternately reciprocates the yokeN forward and back, and through said yoke by the connection described the tongue S during part of the revolution of the shaft D. During the remainder of the revolution of the shaft D the periphery of the cam L is acting on the yoke N in the are of a true circle. Consequently the yoke N remains stationary.

The bar 0 slidesin a groove in the plate B, and is free to move forward and back in the direction required to reciprocate the tongue S, but has no side movement, This last is essential, since it carries the yoke N, which must be held so as onlyto be acted upon by the cam L, and reciprocated forward and back in one direction.

I show in Fig. 2 a feed mechanism which needs no special description, E being the feeddog, F the feed-lever, and Gr the means for adjustment.

The operation of the mechanism is as follows: The material to be seamed having been placed beneath the presserfoot V at V, Fig.

I 3, and over the tongue S, is moved forward by the feed E. The needle H, then descending, pierces the work in its operation of forming a stitch, either by looping or shuttle mechanism. After the needle H has entered the work the cam L, actuated by the gears K and J, begins to act on its yoke N, which is moved forward, we will say. The yoke N, through the bar D and its connections P, P, R, and S,

causes a corresponding movement in the tongue S. At this time the feed has dropped below the surface of the Work-plate and by suitable mechanism is being drawn back preparatory to coming into action, and the space is clear between the work-plate and the bottom of the presser-foot in advance of theneedle for the tongue to act upon the work, which is pressed down upon it by the presser-foot. The movement given the tongue S, as described, is conveyed by it to the fabric which is over it, and the fabric is piled or pressed against the side of the needle. The needle,

during the movements of the tongue, performs its work, and, when the tongue is stationary, because of the true arcs of the cam L, acting on the yoke N, it rises clear from the work and plate, and the feed rises into action andmoves the piled fabric forward, giving it a sort of twist, so that the needle at its next descent will penetrate the fabric one side of the preceding stitch. WVhile the needle is in the work, the cam L again acts upon the yoke N, causing this time a reciprocation backward, which movement is conveyed to the tongue S. The material is piled or twisted in an opposite direction, the result of which when a continuous series of stitches is made is a line of zigzag sewing.

A peculiarity of this mechanism is that the movement of the fabric required to make a zigzag or irregular stitch is confined by that portion of the fabric near the needle. After it has passed beyond proximity to the needle the fabric is fed forward straight. This is of particular advantage to me in making the cut hose covered by my Patent No. 214,354, granted April 15, 187 9, reissued March 9, 1880, No. 9,113, since it allows of the use of a stationary trimming device, and thus lessens any strain on the mechanism when driven at high speed.

I claim- 1. The combination of the under-feed device, the pressure-foot, and the stitch-forming mechanism ofasewing-inachine, with a tongue arranged entirely in front of the needle, and means for reciprocating the same at right angles to the line of feed, substantially as set forth.

2. A tongue arranged entirely in front of the needle and means for reciprocating the same at right angles with the line'of feed, in combination with a pressurefoot cut away on its under side in front of the needle, whereby the tongue can be reciprocated in close proximity to the needle, substantially as described.

In testimony whereof Iaffix my signature in presence of two witnesses.

JOHN BIGELOW.

Witnesses:

G. W. BALLOOH, L. DEANE.

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