US2068671A - Sewing machine - Google Patents

Description

Jan. 26, 1937. A. H. GOODWIN SEWING MACHINE Filed NOV. 17, 1934 Patented Jan. 26, 1937 UNITED STATES PATENT OFFICE SEWING MACHINE Application November 1'7, 1934, Serial No. 753,461 In Great Britain November 30, 1933 3 Claims.

This invention relates to sewing by machine and is particularly, but by no means exclusively, concerned with the sewing together of parts of leather or similar material such as those habitu- 5 ally employed in making up the uppers of boots or shoes which will hereinafter, for convenience, be referred to simply as shoes.

It is now well known to produce on the edges of shoe upper parts an effect of finishing by the use of apparatus which sears and shrinks the margin of the material on what is to be the unexposed side, generally the flesh side of a piece of leather.

One particular shoe part that has one edge commonly treated by such searing process is the toe cap, the seared or finished edge being the one that appears across the toe cap from side to side in full view when the shoe is in wear, the toe cap overlying a measurable margin of the vamp or 2 similar part of the upper, and being connected thereto by one or more lines of sewing. For the purpose of illustration only the sewing of a toe cap to a vamp will be the only specific shoe upper part sewing operation dealt with hereinafter. In

25 sewing together toe caps and Vamps of shoe uppers, it is usual to guide the finished edge of the toe cap by a rigid member fixed to the presserfoot of a sewing machine, the main part of the foot pressing upon the toe cap and the guiding 30 member passing over the vamp.

Since shoe toe caps vary considerably in thickness in different types of shoes, and for due control of the work, it is necessary that some pressure should be applied to the toe cap in order a that it may properly be fed through the sewing machine, a practice has grown up of employing upon the presser-foot an edge gauge having a lower part of small thickness which projects below the general surface of the presser-foot only 40 a small distance, which is often less than the thickness of toe caps being dealt with.

This employment of a thin edge gauge results from the fact that if a gauge projecting below the presser-foot a greater distance than the thickness of the toe cap were used, all the pressure of the foot would be taken upon the gauge and transmitted only to the vamp, leaving the toe cap improperly controlled.

When such a thin edge gauge happens to be 50 used with a toe cap that is thicker than the downward projection of the gauge, it has been found that the lower corner of the edge guide is apt to mar the finished edges of the toe caps at the point where such corner contacts therewith, or

55 even to allow the finished edge to pass partially under it, thereby causing the edge of the toe cap in the completed upper to lie out of parallelism with the lines of stitching.

It is an object of the present invention to provide means for avoiding marring of the work in 5 the ways last indicated and a feature amongst the several features of the invention resides in the provision in connection with a presser-foot for a sewing machine of an edge guiding member which is self-adapting to the thickness of 10 work pieces being fed under the presser-foot. The above and other features of the invention will become apparent from a consideration of the following description, given by way of example and with reference to the accompanying drawing of 15 a preferred construction, according to the invention, for a twin-needle shoe upper stitching machine of customary character.

In the drawing:

Figure 1 shows a perspective view of the said preferred construction embodying a presser-foot and edge gauge;

Figure 2 is a diagram showing in section the device of Figure 1 operating upon a shoe toe cap and vamp; and

Figure 3 is a similar diagram to Figure 2 showing a condition of affairs likely to occur with a presser-foot and edge gauge as normally heretofore used.

Referring now to Figure 1, the presser-foot embodies a plate l0 which has a leading edge l2 at right angles to the direction of feed and slightly upturned in the usual way to allow work pieces to lead easily under it, and an upstanding stem portion I4 adapted to embrace and be fixed to the lower end of the usual presser-foot bar of a twin-needle sewing machine of the character referred to. Attached to the upper surface of the plate I0 is an edge guide I6. This edge guide has one slotted arm which lies on the upper sur- 4Q face of the plate ID, the slot allowing the guide to be adjusted so that its actual work guiding edge, which is formed upon a flat portion I8, is at the required distance from the lines of sewing produced by the needles which respectively pass through holes 20 and 22 in the plate Ill. The part l8 of the edge guide is connected by a thin curved springy portion 24 to the portion Hi. This springy portion 24 extends from the slotted arm forwardly beyond the front edge of the plate I0 of the presser-foot and then curves downwardly and rearwardly to join the guiding portion I8. The fiat work guiding portion I8 is thus supported so that its upper surface is always below the work engaging surface of plate l0 and can extend directly beneath the plate, if desired. It can therefore be adjusted to bring its work guiding edge at any desired distance from the lines of sewing. To prevent the work guiding portion of the edge guide from taking the full pressure of the presser-foot off the materials being sewed, it is made thinner than the top layer of material operated upon. Work is presented to a machine carrying a presser-foot and edge gauge as above described with the toe cap or similar part that is to overlie another part of the work under the plate I with its edge against what is the rear edge of the portion 18, as seen in Figure l, and with the other part of the work under the part I8, as shown by Figure 2, in which the work part 26 represents a shoe upper vamp and the part 23 a toe cap which is being sewn to the vamp by the lines of stitching indicated at 36. The plate Ill rides upon the upper surface of the toe cap and presses it upon the vamp which lies upon the usual work table of the sewing machine. The part l8 of the edge gauge, by reason of its springy nature provided by the portion 24, rides with a light pressure upon the vamp 26 so that there is no space between the lower face of the part l8 and the vamp into which the extreme edge of a toe cap finished-by searing, as aforementioned, could project.

Referring now to Figure 3, this shows what can occur when a toe cap 28 finished as just referred to is being sewn to a vamp 2'6 with edge guiding devices as heretofore commonly used.

The portion H8 of the edge gauge is unyieldingly connected with the upper portion I Hi thereof and, as shown, projects below the presser plate 16 to a less distance than the thickness of the toe cap illustrated. The lower edge or corner I20 of the portion H8 then bears against or upon the rounded portion of the finished edge of the cap and is apt, in commercial practice, to form an indented line therein, spoiling its appearance. Furthermore, it occurs sometimes that such a finished edge of a toe cap has a considerably larger radius of curvature than the example shown in the diagram and in such event the extreme edge of the toe cap is likely to become pressed sideways by the worker of the sewing machine partly under the portion H8, causing the edge to project further over the vamp than is desired, and thus causing misalignment between the cap edge and the line of stitching.

The disadvantageous conditions just referred to manifestly cannot occur with the construction illustrated by Figures 1 and 2 in which the springy character of the guide ensures that the part i8 is kept down in contact with the vamp 26 throughout an operation of sewing a vamp and toe cap together. The presser-foot I0 will, in the usual working of a sewing machine, be lifted slightly in each cycle of operations, that is, for each stitch, to relieve the pressure of the foot on the work in order that the latter may be fed forward for the next stitch. This lifting of the presser-foot will not usually or necessarily lift the part l8 entirely out of contact with the vamp which will then press lightly upon the vamp when the presser-foot is raised and more heavily when the foot is down.

The invention having been thus described, what is claimed is:

1. In a sewing machine the combination with a presser-foot having a horizontally arranged work engaging plate of an edge guide comprising a work guiding portion arranged to bear upon the work below the plane of the work engaging surface of the presser-foot, an arm secured upon the upper surface of said plate so as to permit an adjustment of the work guiding portion of the edge guide transversely of the line of stitching, and a thin curved springy portion connecting the arm and work guiding portion and extending over the leading edge of said plate to permit the location of the work guiding portion beneath the plate. 7

2. In a sewing machine for joining the edges of materials extending in opposite directions having their margins overlying each other, the combination with a presser-foot having a horizontally arranged work plate for engaging the top layer or" material, of an edge guide comprising a fiat work guiding portion arranged with its upper surface below the work engaging surface of the presser-foot plate and with a thin springy portion curved about an edge at right angles to the direction of feed of the presser-foot plate and adjustably secured to the upper surface of the plate to permit movement of the guide within the space between the work engaging surface of the plate and the under layer of the material transversely of the line of stitching.

3. In a sewing machine for joining the edges of materials extending in opposite directions with their margins overlying each other, the combination with a presser-foot having a horizontally arranged work engaging plate, of an edge guide comprising a fiat work guiding portion thinner than the top layer of material being sewn arranged with its upper surface below the work engaging surface of said plate, means connected with the presser-foot for yieldingly forcing the work guiding portion of the edge guide against the under layer of material being sewn, and an adjustable mounting on the presser-foot for permitting movement of the work guiding portion of the edge guide at right angles to the seam line to any position within the space between the presser-foot and the under layer of the material.

ALBERT HOWARD GOODWIN.

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