US2669953A

US2669953A - Shoe sewing machine

Info

Publication number: US2669953A
Application number: US163279A
Authority: US
Inventors: Raymond L Slinkard
Original assignee: United Shoe Machinery Corp
Current assignee: United Shoe Machinery Corp
Priority date: 1950-05-20
Filing date: 1950-05-20
Publication date: 1954-02-23
Anticipated expiration: 1971-02-23

Description

Filed May 20, 1950 Patented Feb. 23, 1954 Raymond. L... slinkard, Cape. Girardeau,, Mo.., as-

signor toUhit'edi Shoe Machinery Cori-9oration, Fl'emington, N2, Jz, a corporation oiNewJersey" Application May 211; 195 Serial N 0;. 163,279;

3; Claims.

' The: present inventionrelates; primarily to. im..- movements in shoe. sole sewing machines. and, more. particularly. to. a sewing: machine arranged to direct a repe: rubber wrapper. strip having. a tacky surface-into a-seamof a. shoe:-

Crepe rubber'imshoe construction ordinarily is used: with cement. to. attach theparts in; place, thecrepe-rubber being: applied by hand. Because of the tacky surfaces or crepe: rubber, considerable d-iiiculty hasheretofore. been; experiencedin leading, such parts progressively intooperative. positicn in a sewing, machine; without manual assistance. Extremely thinap-arts. composed of crepe materiaL are particularly diflicult to: control because'of: their. great-flexibility and tozkeep-separate from other parts, before attachment because of: their lively; resiliency.

A-nobiect' of the-present. invention is toproyide a sewing;- machinewith a. guide.- forv a tackysurfaced wrapper-strip; which. guidawillbe efi'ective directing. the.- strip: with: an abrupt widthwise bend toward; the point 0t operation. of the. machine, in: such a way that: obstruction of. the Work by: reason of. adhesive, contact between the tacky surface: on thestrip and. they guide=isreduced to. a minimum; Another. object. is; to improve machine operationsfor attaching; a-crepe rubber strip to ashoe in. a. particularly desirable manner. with the. border: of the crepe rubber strip brought progressively into; accurateregisten with thefline I;

Inaccordance with the above noted andother objects, the. illustrated machine is arrangedv with a: work clamping presser foot, a. combined work support and: guide formed with an open sided slot. for receiving; one border of awrapper strip bent. abruptly against. the. bulging upper of. the shoeinto. angular relation with the other border, imwhiclr a retaining, channel. is. provided; within the slot for an enlargement along the border of the wrapper strip, the retaining channel acting to prevent adhesive contact between the wrapper strip and the surfaces of the slot in the: guide and being provided with an overlying apron and an inclined gaging surface. To avoid obstruction through adhesive contact of the wrapper strip. in the guide, the enlargement on the strip comprises a nontacky welt secured separately to the. strip and so arranged relatively to the strip that when the welt is directed accurately into the. seam. line the border of. the wrapper strip automatically. follows. With. such. arrangement the. inclination oi the gaging suriaceisadjusted to." induce. widthwise. squeezing; actionon.the. welt,

thetend'ency is to press. the wrapper strip. firmly 2: against. the bulgei'n the: shoe. upper, providing a; desirable: Weather. excluding, construction.

To complete the shoe sewn. on the. machine a crepe. rubber outsole is. secured.- to the. shoe with its. edge face attached to the. outer borderv of the wrapper strip.

These and. other teatures. of the invention. as hereinafter described and claimed will. be apparent iromlthefollowing description taken in. 00.11? nection. with the. accompanying drawin s, in which.

Fig, 1 is. a, view in right side, elevation. and partly. in. section on. an. enlarged scale, or; those portions of. a. shoe. sole sewing. machine. necessary to. illustratethe features. of the present. invention;.

Fig. 2.is. a. detail view infront. elevation of the work support. in the machine. illustrated in. Fig. 1. showing. thapositionof a. Wrapper strip being directed into. the. point; of... operation of the. ma.- chine;

Fig. 3 isja plan view of.the.worlt.suppcrt;,

Fig. i is a. view in. right side. elevation of the Work. support;

Fig 5. is. a sectional viewof a. wrapper strip guide in the worksupport;

Fig. 6. is a perspective view of the. wrapper strip. and enlargement. Welt secured thereto. be,- fore. attachment. to a. shoe;-

Fig', 7. is a sectional. view. of. a shoe. embodying the. features of, the presentinvention; and

Fig. 8: is, a,sectio.nal. view. of. aportion oil a shoe constructed. with. a rectangular welt.

The..illustrated. machine. is intended for opera.- tion. on a. stitchdown. type. of. shoe in which an upper 8. is. connected. to. aninsole It by angularly dis-posed thread lasting. stitches. [2i passing through the. marginal flange. of the; shoe. which projects beyond the. bulge ot the upper.. The stitches L2. form, a, thread. lasting, seam. which. is insertedwhilelthe. upper and. insole are supported on-alast, indicatedaat- IA. The. machineisparticularly intended for sewing a, crepe, rubber wrapper strip. to. the. marginal. flange. of the. shoe. Such wrapper strips;- ordinarily, have: extremely tacky surfaces so that adhesive contactbetween them. and. the: surfaces,- oi. the, machine. parts, or 0t. thev shoe. before. the. point. of attachment is reached tend, to render. it, difficult, if not. impossible, to. guide or. feed. the. strip. accurately with relation to the line. of sewing. Accordingly,v it has beenthe practice. with thause. of. a creperuhber wrap-per strip. to attach: one border of the strip-temporarily to..a,. hoeby apreliminary hand cementing operation. Thereafter, the. exposed surfaces oi the. wrapper strip. are covered. with tively thin section to be directed into the point i of operation of the machine in accurate relation to the line of the seam inserted by the machine without the necessity of preliminary hand cement attachment. The guiding action on the crepe rubber wrapper strip H is accomplished by the use of an enlargement along one border of the wrapper strip led into the machine with the strip. As shown in Fig. 6, this enlargement consists of a separate nontacky welt l8 secured by a seam is to the wrapper strip. The welt I8 is of rectangular cross-section with one edge along a corner havin a bevel at an angle of approximately 30 to the sides of the welt.

In directing the wrapper strip into the seam, the enlargement border of the strip passes through a combined work support and guide 2! having an open sided slot 22 inclined upwardly and forwardly toward the point of sewing op erations in the machine. The open side of the slot 22 faces forwardly of the machine so that the wrapper strip extending from the slot is bent downward abruptly against the bulging upper of a shoe, the upper forcing the wrapper strip against the forward face of the work support.

To prevent displacement of the wrapper strip and welt from the guide and to avoid adhesive contact between the strip and the guide, the guide has a retaining channel 24 formed by a rearward gaging surface 25 of the slot 22 inclined relatively to the seam line and a re-entrant lip 25 the edge of which extends into the slot of the guide and enters between the wrapper strip and the bevel 2B of the welt l8, the distance between the lip 25 and the rearward surface 25 of the slot being less than the width of the welt. The inclined surface 25 induces a widthwise squeezing action on the Welt, tending to press the wrapper strip more firmly against the shoe upper as the shoe is fed in the machine. The lip 2-6 acts to hold the extreme edge of the wrapper strip from being raised from the channel during bending action against the bulging upper of the shoe and to retain the welt from displacement otherwise. The pressure of the upper against the wrapper strip in bending it is almost entirely exerted against the forward surface of the work support and does not obstruct movement of the wrapper strip suiiciently to interfere with the operation of the machine, the shoe upper mov ing with the wrapper strip to oifset its tendency to adhere to the work support. Where necessary the operator of the machine may exert a slight widthwise tension on the strip to bring the level on the welt into firm guiding engagement with the lip 26.

As a means for preventing adhesive contact between the upper surface of the wrapper strip and the shoe before the sewing point is reached, the guide which is integral with the work support has a strip overlying apron 28 terminating at the clamping point of a presser foot 29 and the work support 2|. The presser foot 29 acts on the margin of the shoe to clamp it both against the apron 28 before the sewing point is reached and against a raised shelf portion 30 of the work support through which a needle receiving opening 32 passes beyond the sewing point. Thus the work is fixedly clamped at the sewing point with the shoe guided accurately through rearward pressure on the bent down wrapper strip, which in turn is directed by the forward surface of the work support. The wrapper strip and welt also are directed between the lip 26 beneath the apron 28 and the rearward face 25 of the slot 22 which is inclined forwardly and merges with the vertical shoulder behind the shelf 30, the slot face 25 being disposed at an angle to the seam line approaching the vertical shoulder of the shelf as the shoe is fed.

Besides the work support 2! and the presser foot 29, the sewing machine in which the invention is embodied comprises the usual curved hook needle 34, a curved awl 36, a shuttle 38, a locking thread case 40, a needle looper 42, a thread finger 44, and other devices similar to those disclosed in United States Letters Patent No. 1,169,909, granted February 1, 1916 upon application of Fred Ashworth. The machine is intended for operation upon shoe soles, the parts operated upon being clamped between the work support 2 l and the presser foot 29 during stitch formation. After the completion of each stitch the parts operated upon are fed a stitch length by the awl 35 while engaging the work, the work being released from the clamping action of the presser foot at this time. Upon release of the work from the presser foot, the parts are raised slightly from the engaging surfaces of the work support so that adhesion between the crepe rubber wrapper strip and the Work support is substantially avoided. Furthermore, the principle clamping pressure of the presser foot is transmitted downwardly upon the nontacky welt i8 which shields the work support in a large degree from contact with the tacky surfaced wrapper strip.

The bevel at on the welt I8 has two purposes, namely, to enable it and the wrapper strip border to which it is attached to be retained in the guide and to provide an improved shoe construction. After sewing the wrapper strip to the outfianked upper and insole, the margins of the upper and insole are trimmed to register with the welt and the unattached border of the wrapper strip is carried about the welt into lasted relation with the edges of the upper and insole. The welt l8 and its attaching stitches also are enclosed by the wrapper strip. To secure the wrapper strip in lasted over position, the shoe is completed with the attachment of a crepe rubber outsole 46 (see Fig. 7) all of the parts having been disposed with their edge surfaces in registry to provide a smooth surface over which the wrapper strip is lasted. I The wrapper strip is brought into contact with the edge face of the outsole and cemented thereto.

By reason of its accurate and uniform location the wrapper strip may be of such width that it reaches exactly to the lower tread surface of the outsole 45 and the thickness of the material from which the wrapper strip is composed may be much thinner than heretofore employed for similar purposes. The enlargement welt [3 provides an ample stitch retaining reinforcement to'the sewed border of the wrapper strip and prevents expansion. or distortion of the wrapper strip along its attached border during sewing operations.

With reference to Fig. 7 of the drawings it will be noted that the seam; indicated at 48, inserted by the machine, passes through the welt I8, one border of the wrapper strip IS, the outiianged margin of the upper 8 and the insole ID. The upper threads of the stitches, however, are concealed by the folded over wrapper strip and the lower threads by the outsole 46. In this way a weatherproof construction is provided.

The nature and scope of the invention having been indicated and a particular embodiment having been described what is claimed is:

1. A shoe sewing machine for attaching a wrapper strip having a tacky surfac to the marginal flange on a shoe projecting beyond the bulge of the upper, having a needle and a presser foot for clamping the work in sewing position, in combination with a work support provided with an integral confining guide for a nontacky welt, to one edge of which the wrapper strip is secured, an overlying apron on the work support terminating at the point of operation of the needle to prevent contact between the wrapper strip and the shoe flange until the sewing point is reached and a gaging surface on said guide inclined relatively to the seam line toward the shoe in the direction of work feed to induce widthwise squeezing action on the welt tending to press the wrapper strip against the bulge of the upper as the shoe is fed.

2. A sewing machine for attaching a wrapper strip having a tacky surface to the marginal flange on a shoe projecting beyond the bulge of the upper, having a needle and a presser foot for clamping the work in sewing position, in combination with a work support provided with an integral confining guide for a nontacky welt to one edge of which the wrapper strip is secured, an overlying apron on the work support terminating at the point of operation of the needle to prevent contact between the wrapper strip and the shoe flange until the sewing point is reached and a re-entrant lip in the guide beneath the apron to enter between the wrapper strip and the welt to retain the welt from displacement.

3. A sewing machine for attaching a wrapper strip having a tacky surface to the marginal flang on a shoe projecting beyond the bulge of the upper, having a needle and a presser foot for clamping the work in sewing position, in combination with a work support provided with an integral confining guide for a nontacky welt to one edge of which the wrapper stri is secured, an overlying apron on the work support terminating at the point of operation of the needle to prevent contact between the wrapper strip and the shoe flange until the sewing point is reached and a re-entrant lip in the guide beneath the apron to enter between the Wrapper strip and the welt to retain the welt from displacement, the wrapper strip projecting from the guide between the apron and a raised welt supporting shelf on the work support against which the work is clamped by the presser foot.

RAYMOND L. SLINKARD.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 644,634 Pittrofi Mar. 6, 1900 1,723,994 Boatman et a1 Aug. 13, 1929 2,428,431 Murphy Oct. 7, 1947 2,505,158 Stritter Apr. 25, 1950 2,514,265 Spatola July 4, 1950 2,521,464 Lathan Sept. 5, 1950 FOREIGN PATENTS Number Country Date 845,776 France May 22, 1939