US2387813A - Moccasin seam sewing machine - Google Patents

Description

Oct; 30, 1945. F. R. SPEIGHT 2,387,813

MOCCASIN SEAM SEWING MACHINE Filed May 22, 1945 Patented Oct. 30, 1945 MOCCASIN SEAM SEWING MACHINE Francis ,R. Speight, Dedham, Mass, assignor to United Shoe Machinery Corporation, Flemington, N. J., a corporation of New Jersey Application May 22, 1943 Serial No. 488,031

11 Claims.

The present invention relates to moccasin seam sewing machines and more particularly to improvements in edge trimming devices for the types of machines disclosed in United States Letters Patent to Ashworth No. 1,975,914, granted October 9, 1934, and No. 2,221,320, granted November 12, 1940, for sewing together the top piece or tongue and the side piece or vamp of a moccasin or moccasin type shoe upper. v I

After sewing a moccasin or moccasin type shoe upper with one of the patented machines, it is the usual practice to finish the seam by trimming the surplusage of material from the edgesof the parts operated upon to eliminate uneven register between the edges and to smooth rough portions along the edges caused by projecting fins or other irregularities produced while preparing the moccasin parts for sewing. In-most cases, the finishing operation is performed by hand, the edges frequently being waxed to present a pleasing appearance. In some instances, attempts have been made to trim the surplusage along the edges while sewing but, in order to avoid displacement of the edges after being trimmed, the trimming has been performed in a machine along the seam line beyond the point of sewing operations where the moccasin parts are firmly secured together by stitches. One difficulty with this method of trimming and sewing is encountered with moccasins or moccasin type seams having a substantial curvature, as around the toe portions of small-sized moccasin or moccasin type shoe uppers. Where a substantial curvature is met in a moccasin seam with a knife located beyond the sewing point, there is a tendency for the edges of the moccasin parts to be drawn away from the knife so that little or no trimming action takes place, while along the straighter portions of the seam, a deeper cut is made. As a result, irregular appearance may not be avoided entirely in spite of trimming.

Objects of the present invention are to avoid these difficulties and to improve generally the construction and mode of operation of a moccasin type seam sewing machine having an edge trlm-- ming knife so arranged that uniform trimming operations will be secured throughout the length of the seam, regardless of its curvature or the size of the moccasin or of the shoe upper being operated upon.

Another object of the invention is to provide a moccasin seam sewing. machine with an edge trimming and finishing knife which will remove uneven edges uniformly, smooth any roughness along the edges, and also will produce an ornamental effect where such is desirable. Further objects are to simplify the construction of any edge trimming knife for a moccasin seam sewing machine and to so locate the knife that material will be severed from the work in the form of elongated strips which will readily be carried out of the path of the stitch forming and operating chine is provided with a presser cooperating with the work-supporting means and having a tip such as is disclosed in present inventors United states Letters Patent No. 2,304,964, granted December 15, 1942.

The presser tip of that patent is formed with a projection acting along the seam line ahead of the point of needle operation for compressing the material of the work to crowd it into the apex of the work-engaging surfaces of the work-supporting means opposite that portion of the work where the knife acts. The projection on the tip, while compressing the material of the work and crowding it into the angle of the work-supporting means, forms the work into a shape which is more readily trimmedin a uniform manner even though the cutting edge of the knife becomes somewhat dulled. The compression of the parts operated upon ahead of the sewing point also tends to prevent any displacement of the edges between the points where trimming occurs and where the stitches are inserted and is conducive to better register of the edges even when inaccurately assembled in the first place. Thus, the disadvantage of trimming the edges ahead of the sewing point is more than offset by the effects of compression at the trimming point and by numerous other improved results.

One form of this feature of the invention, in which an ornamental as well as improved structural effects are produced, is embodied in a construction in which a knife is employed, formed with angularly disposed cutting edges arranged in parallel relation to' the work-engaging surfaces of the work-supporting means to trim off thin strips from the grain or finished sides of the moccasin parts along the surfaces of the work between the exposed threads of a seam. Trimming on the grain surfaces of the moccasin parts in this way also enables the edges of the parts to be trimmed into accurate register particularly where 'the parts are beveled before the sewing and trimming operations are-performed. Ordinarily, the materials of the moccasin parts are relatively spongy and easily compressible beneath the grain or finished surfaces so that, when these surfaces are removed in advance of the sewing operation, the compression of the parts by the presser tip assists in forming a seam along which the edges are uniformly shaped without wrinkling or tendency towards relative displacement.

These and other features of the invention are embodied in the devices, combinations and arrangements or parts hereinafter described and claimed, the advantages of which will readily be understood from the following description taken in connection with the accompanying drawing, in which:

Fig. 1 is a view in side elevation, looking from the right, of portions surrounding the operating point in a sewing machine embodying the features of the present invention;

Fig. 2 is a plan view on an enlarged scale of the work support of the machine of Fig. 1, indicating the positions, along the line of the seam, of the needle, awl and trimming knife; 7

Fig. 3 is a detail view of a portion of, the work support broken'away, illustrating the action of the trimming knife on the work;

Fig. 4 is a view in side elevation of the workclamping parts of the machine and the trimming knife, showing their relation to the top piece and side of a moccasin;

Fig. 5 is a detail sectional view of a portion of a moccasin seam, after sewing and trimming, in the machine of Fig. 1;

Fig. 6 is a sectional view in side elevation of a modified construction for a portion of the worksupporting parts in a machine embodying the invention; and

Fig. 7 is a sectional plan view of the machine of Fig. 6 taken along the line VII-VII of Fig. 6.

The machine illustrated in Figs. 1 to 4 in its construction and mode of operation is similar to that of Patent No. 2,221,320, above referred to, and is intended to operate on bevel edged moccasin parts comprising a top piece or plug and a vamp or side part, indicated respectively at 2 and 4. Previously formed 30 bevel faces on the parts are held temporarily in register'by a coating of adhesive cement. During sewing operations, the seam is inserted through the registering bevel faces, the stitches of the seam being exposed only at the outer surfaces a short distance from the extreme edges of the parts.

The illustrated machine is provided with a curved hook needle 8, a curved work-penetrating and feeding awl 8, a rotary horn ill, a loop takeror rotary hook l2, which carries loops of needle thread over a locking thread case contained therein, and other stitch forming and thread handling devices of the usual form. The work is fed through the machine by movement of the awl while engaging the work towards a position of alinement with the needle so that the needle will enter the perforation formed by the awl. When the awl withdraws from the work, it is back-fed the length of a stitch and again penetrates the work.

The moccasin parts are clamped in position during formation of each stitch in the machine foot l6 and a rotary disk I8 forming a presser tip for thehorn Ill and having two opposed conical work-engaging surfaces disposed at an angle points of of substantially 60 so as to fit accurately within the angle of the parts operated upon. The work support and presser foot have work-engaging surfaces arranged at substantially the same angle and parallel to adiacent conical portions of the presser disk, thus enabling the work to be gripped firmly over a substantial area without danger of cutting or injuring the surfaces clamped.

If the parts of the moccasin operated upon have been assembled with their edges out of register along any portion of the seam or if, in beveling the parts in preparation for the cementing operation, relatively thin fins or irregular projections, such as indicated at l9, are formed on the extreme edges of the parts, these irregularities will prevent accurate register of the extreme edges during the sewing operations and will require further treatment before an acceptable appearance is presented. To remove the irregularities, it has been the practice either to trim the edges by hand, after the complete seam has been inserted, or to secure a knife to a sewing machine, along the seam line beyond the point of sewing operations where one or more stitches are already inserted. Thus, the edges of the parts heretofore have been trimmed after sewing.

According to a feature of the present invention, the illustrated sewing machine is provided with a work trimming knife 20 located along the seam line in the direction of feed, ahead of the point of sewing operations to trim or otherwise remove surplus material from the work along the edges before the stitches are inserted, relying upon the pressure of the work-supporting, clamping and stitch forming devices to hold the parts securely in proper relative positions so that no displacement of the extreme edges will occur between the trimming and sewing.

The trimming knife of Figs. 1 to 4 consists of a grooved block forming a lever fulcrumed on a vertical pin 22 secured in the work support. The block is arranged with its groove facing the front of the machine and the cutting edges 23 of the knife are formed by cutting away the corners on a rearwardly inclined face 24 of the knife, the inner sidesof the groove in the block intersecting the cut-away corner surfaces, indicated at 2B. The groove in the block is cut with a V shape, the inner sides of which are disposed at substantially 60 and extend in the direction of feed nearly parallel to the work-engaging surfaces of the work support and presser foot. I

In order to prevent the trimming knife from cutting too deeply into the work and to guide the work accurately with the seam a uniform dis tance from the trimmed extremities of the edges, the points on the knife, which are formed by the intersections of the rearwardly inclined face 24 and the V-shaped groove, are rounded at 21. The rounded portions of the knife comprise blunted work-guiding elements of an adjustable back gage. 'To insure proper cutting action, the knife is so located that its cutting edges project at anangle toward the front of the machine, and

mined position and form work guiding or back faces of the work, therefore. are compressed only and not cut by the rounded points 21 on the knife, and the work is severed after passing the points along those surfaces only engaged by the cutting edges 28 of the knife.

When operating upon moccasin parts presented to the machine, the work-supporting and clamping devices compress the parts and force them into the groove of the knife. In order to insure complete separation of the chip cut of! the work by the knife, the knife is so adjusted that the sides of the groove are either in the same plane or slightly to the rear of the corresponding surfaces of the work support and presser foot.

The knife and back gage are adjustably secured in proper operating position by a set screw 28 passing through a slot in the end of the knife, opposite the cutting edge and extending into threaded relation with the work support. The knife is so located that its cutting edges are inclined forwardly and to the right towards the front of the machine and extend along the line of the seam ahead of the sewing point and between points opposite the needle andthe awl paths. By inclining the cutting edges of the trimming knife and locating them in this way, a cutting action occurs with a uniform outline at the extreme edges, and a sharp apex is formed on the work throughout the length of the seam with a V shape corresponding to the groove in the knife.

movement, before the work is fed, by the awl. After penetrating the work, the awl moves laterally into line with the needle and causes the knife to trim the work. Before the awl withdraws from the work, the moccasin parts are clamped by the action of the presser and presser foot. The awl then withdraws and back-feeds while the work is clamped against displacement. As soon as the awl withdraws from the work in each sewing cycle, the needle follows closely, entering the awl perforation, thus maintaining the proper relationship in the parts until each stitch is comand the knife is adjusted with its cutting edges in the same planes with the work-engaging surfaces of the work support and presser foot, the compression of the work and the curvature of the presser disk l8 being sufiicient to cause the moccasin parts to bulge against the cutting edges of the knife in such a way that thin stripsof material will be trimmed from the outer grain or finished sides of the moccasin parts between the threads of the seam after being inserted by the needle. The appearance of the work after being trimmed and released from compression in this way is indicated in Fig. 5, the extreme edges of the parts being brought into accurate register, and narrow areasof roughened leather, indicated at 29, are exposed. One. advantage of trimming thin strips off the grain surfacebetweenthe edges and-the seam in this way is that less distortion The parts are held securely against relative results in theshape of the completed moccasin.

There is a tendency for the threads in each stitch, when each is set, to compress material of the parts surrounded and to pucker the adjacent materials particularly along the edges. The tendency to pucker is most noticeable along the grain surface since this part of any leather material is stiffer than the softer, spongier underlying material. By trimming off the grain surface, the tendency to pucker is substantially reduced, since the underlying material easily expands or contracts to suit the shapes into which it is formed while sewing, and a pleasing ornamental appearance results.

Referring to Figs. 6 and 7, a machine is illustrated similar to that disclosed in inventors prior patent. In the machine of these figures, the work is clamped in operating position without the use of a presser foot in addition to the presser for compressing the parts. A work support of this machine is provided with a V-shaped notch and is composed of two parts 30 and 3| secured together by a pair of spaced screws 32. Proper alineinent between the parts is maintained by one or more vertical dowels 34 passing through the parts. In the machine of inventors patent, the two parts of the work support are. separated by a number of spacing plates in order that the distance between the work-engaging surfaces of the work support may be changed when work of different thicknesses is operated upon.

The knife of the present machine, indicated at 36 in Figs. 6 and 7. has a straight cutting edge and acts itself as a spacer between the parts 30 and 3! of the work support so that no full-length spacing plates are required. Near one end of the work support, however, the parts are held separated by a spacing block 38 through which one of the securing screws 32 passes. When the other securing screw is loosened, the position of the knife may be changed to suit the conditions under which the machine is operated. As in the form of the invention described in connection with Figs. 1 to 4, inclusive, the knife 36 is located in a recess between the parts 30 and 3! of the work support at the apex of the angle between intersecting extensions of the work-engaging surfaces.

For the best results, the knife is located with its cutting edge acting in the direction of feed, ahead of the point at which the needle operates where the stitches have not as yet been inserted and between the point where the awl penetrates the work and the point of needle operation. As in the machine of inventors patent, the horn, illustrated at All in Figs. 6 and 7, is provided with work-engaging surfaces extending in the direction of work feed and a notched presser tip 42 having a central projection 44 (Fig, '7) acting between the needle and awl paths. If the cutting edge of the knife is located in the direction of work feed also between the needle and awl paths and opposite to the projection 44, the projection on the presser tip acts to force the work rearwardly into the recess at the apex of the angle between intersecting extensions of the work-engaging surfaces and against the cutting edge of the knife and maintains proper cutting action, even though the knife becomes somewhat dulled. The compression of the work at this 10- cation assists further in the cutting action since it tends to stiffen the work through compression and give it a more nearly permanent shape corresponding to the shape of the work-engaging surfaces on the work support.

The nature and scope of the invention having been indicated and two constructions embodying the invention having been specifically described, what is claimed is:

1. In a machine for sewing moccasin seams, the combination with work-supporting means having work-engaging surfaces extending in the direction of work feed and disposed with relation to each other, to form an angle, stitch-forming devices comprising a needle movable across the angle formed by said surfaces, and a presser having a tip with angularly disposed work-engaging surfaces, of a work-engaging knife located along the seam line ahead of the point of needle operation in the direction of feed.

2. In a machine for sewing moccasin seams, the combination with work-supporting 'means having work-engaging surfaces extending in the direction of work feed and disposed with relation to each other to form an angle, stitch-forming devices comprising a needle movable across the angle formed by said surfaces, and a presser having a tip with angularly disposed work-engaging surfaces, provided with a projection cated/along the line of the seam ahead of the point of needle operation in the direction of feed to compress the material of the work and to crowd it into the [angle of the work-supporting means before each stitch is formed, of a workengaging knife located along the seam line to act on that portion of the work compressed by the presser tip projection.

3. In a machine for sewing moccasin seams, the combination with work-supporting means having work-engaging surfaces extending in the direction of work feed and disposed with relation to each other to form an angle, stitch-forming devices comprising a needle movable across the angle formed by said surfaces, a work-feeding awl acting on the work a stitch length from the needle to form a perforation and to move into line with the needle in feeding the work, and a presser having a tip with angularly disposed work-engaging surfaces extending in the direction of feed provided with a projection entering between the needle and the work-penetrating path of the awl tocompress the material of the work and crowd it into the angle of the work-supporting means,

of a work-engaging knife located along the seam' line opposite the projection on the presser tip.

4. In a machine for sewing moccasin seams, the combination with work-supporting means having work-engaging surfaces extending in the direction of work feed and disposed with relation to each other to form an angle, said surfaces being cut away to provide a recess at the apex of the angle formed thereby, stitch-forming devices comprising a needle movable across the angle,

and a presser having a tip with angularly disposed work-engaging surfaces and acting to compress the material of the work between the work-engaging surfaces of the work-supporting means, and to cause the work to bulge into the recess, of a work-engaging knife having its edge forming an angle, the sides of which are parallel to the workengaging surfaces of the work-supporting means to sever the material bulging from the work within the recess of the work-supporting means,

5. In a machine for sewing moccasin seams, the combination with work-supporting means having work-engaging surfaces extending in the direction of work feed and disposed with relation to each other to form an angle, said surfaces bein cut away to provide a recess at the apex of the angle formed thereby, stitch-forming devices comprising a needle movable across the angle, and a presser having a tip with angularly disposed work-engaging surfaces and acting to compress the material of the work between the workengaging surfaces of the work-supporting means. and to cause the work to bulge into the recess, of a work-engaging knife with angularly disposed cutting edges located along the seam line in advance of the point of needle operation to sever the surface of the bulging work material within the recess of the work-supporting means.

6. In a machine for sewing moccasin seams, the combination with work-supporting means having work-engaging surfaces extending in the direction of work feed and disposed with relation to each other to form an angle, said surfaces being cut away to provide a recess at the apex of the angle formed thereby, stitch-forming devicesi comprising a needle movable across the angle, and a presser having a tip with angularly disposed work-engaging surfaces and acting to compress the material of the work between the workengaging surfaces or the work-supporting means, and to cause the work to bulge into the recess, of a back gage in the recess of the work-supporting means having a V-shaped groove within which the work is compressed by the presser.

'7. In a machine for sewing moccasin seams, the

- combination with work-supporting means having work-engaging surfaces extending in the direction of work feed and disposed with relation to each other to form an angle, said surfaces being cut away to provide a recess at the apex of the angle formed thereby, stitch-forming devices comprising a needle movable across the angle, and a presser having a tip with angularly disposed workengaging surfaces and acting to compress the material of the work between the work-engaging surfaces of the work-supporting means, and to cause the work to bulge into the recess, of a back age in the recess of the work-supporting means having a V-shaped groove within which the work is compressed by the presser, and means for adlusting theback gage towards and from the point of operation of the stitch-forming devices.

8. In a machine for sewing moccasin seams, the combination with work-supporting means having work-engaging surfaces extending in thedirection of work feed and disposed with relation to each other to form anangle, said surfaces being cut away to provide a recess at the apex of the angle formed thereby, stitch-forming device comprising a, needle movable across the angle, and a presser having a tip with angularly disposed workengaging surfaces and acting to compress the material of the work between the work-engaging surfaces of the work-supporting means, and to cause the work to bulge into the recess, of a back gage, and cutting means in the recess of the work-supporting means for guiding and trimming the extreme edges of those portions of the work which are crowded against the back gage and cutting means by the presser.

'9, In a machine for sewing moccasin seams, the combination with work-supporting means havin work-engaging surfaces extending in the direction of work feed and disposed with relation to each other to form an angle, stitch-forming devices comprising a needle movable across the angle formed by said surfaces, of a back gage at the apex of the angle between the surfaces of the work supporting meanaand a knife edge on the back gage, actingadlacent the point of op-. eration of the stitch-forming devices to trim the extremities of the work with a uniform margin.

10. In amachine for sewing moccasin seams, the combination with work-supporting means having work-engaging surfaces extending in the direction of work feed, and disposed with relation to each other to form an angle, stitch-forming devices comprising a needle movable across the angle formed by said surfaces, and a presser having a, tip with angularly disposed work-engaging surfaces extending in the direction of work feed, of a trimming knife at the apex of the angle between the surfaces of the work-supporting means having a V-shaped groove within which the work is crowded by the presser, and work-guiding elements on the knife located along the seam line in advance of the knife edge to prevent trimming an excessive amount from the work being operated upon.

11. In a machine for sewing moccasin seams,.

portion of work compressed by the clampingmeans to trim the extremities on the work pieces with a uniform margin.

' FRANCIS R. SPEIGHT.

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