US2359945A - Shoe sewing machine - Google Patents

Description

Oct. 10, 1944. H. F. SMITH SHOE SEWING MACHINE Filed June 3, 1942 4 Sheets-Sheet 1 Out. 10,1944. L. F, M H 2,359,945

SHOE SEWING MACHINE Filed Julie 3, 1942 4 SheetsSheet 2 Oct. 10, 1944. H. F. SMITH SHOE SEWING MACHINE Filed June 3, 1942 4 Sheets-Sheet 3 Oct. 10, 1944. H. F. SMITH 4 SHOE SEWING MACHINE I Filed June 3, 1942 4 Sheets-Shegt 4 53 5 il/W Patented Oct. 10, 1944 SHOE SEWING MACHINE Homer F. Smith, Chicago, 111., assignor to United Shoe Machinery Corporation,

Flemington,

N. J a corporation of New Jersey Application June 3, 1942, Serial No. 445,548

12 Claims. (C

The present invention relates primarily to improvements in shoe sewing machines and more particularly to curved hook needle machines constructed and arranged to insert stitches with a zig-zag pattern.

With light weight shoes and sandals, the sole and upper materials being of relatively thin gage and of flexible nature are best attached to each other with stitches passing through widely spaced perforations in order to distribute the strains imparted by the stitches over larger areas than with thick work. To obtain essential strength with widely spaced perforations, it has been the practice to employ a seam having a double line of perforations comprising either two parallel rows of stitching separate from each other or composed of one or more common threads. Two parallel rows of stitching with common thread are inserted at the same time in a double line of widely spaced perforations in the machine disclosed in U. S. Letters Patent to Bates No. 2,033,674, of March 10, 1936. One difficulty with the use of the two row stitching of the patent is that the seam has an unconventional appearance at one surface of the parts operated upon. A further difliculty with the use of machines of the type disclosed in the patent is that with shoes constructed according to Goodyear methods, the marginal portions of the sole often roject beyond the contour outline at the bottom of the shoe upper to a less extent along the shank of the sole than about the forepart, The projecting marginal portions of the sole along the shank frequently are of insufl'lcient width to accommodate a double line of stitch receiving perforations, particularly when common thread Stitching in opposite lines is inserted simultaneously as by two needles in the patented machine. The shank portions of the outsole, if relatively narrow, must therefore be sewed subsequently in a separate operation with a single line seam. In order to sew a narrow shank on a Goodyear shoe, it is thus necessary to perform two sewing operations either on the same machine where two parallel row separate seams are inserted about the forepart or on separate machines, one of which is provided with two needles to form a seam with a double line of spaced perforations about the forepart and the other of which is provided with a single needle to form a conventional straight line seam in the shank of the shoe. Separate sewing operations not only cause loss of time but add to the cost of the shoe and require extra care and effort in handling the shoe. Furthermore, when sewed on separate ma.-

of par s hereinafter described and claimed, f

chines or in separate sewing operations on the same machine, the threads of the seams will not be continuous about the shoe but will present one or more points of weakness caused by breaks in the threads.

An important object of the present invention is to improve the construction of a shoe sewing machine and to enable it to sew a zig-zag seam without complicated and expensive additions to the stitch forming devices. Another object is to provide means in a shoe sewing machine for enabling a seam to be inserted which consists of stitching extending through a double line of spaced perforations in the projecting marginal portion of a sole about the forepart of a light weight shoe or sandal and with single line stitching along the shank of the shoe without the objectionable results ordinarily encountered in doing this type of work.

With these and other objects in view, one feature of the present invention is embodied in a curved hook needle lockstitch sewing machine having means for clamping and feeding the marginal portions of a shoe sole lengthwise of the sole edge and means for moving the shoe transversely of the edge between stitches to form a zig-zag seam. This feature of the invention also contemplates the provision of a machine for inserting stitching in a double line of relatively widely spaced perforations with a single needle along the projecting marginal portions of the sole whether the seam assumes a zig-zag or other double line pattern. By providing a machine of this nature, a seam may be inserted which is both ornamental and effective in securing together the relatively thin materials of a light weight shoe. Another advantage of using a single needle, according to this feature, is that the machine may easily be adjusted even during sewing from an operation in which double line perforation stitching is inserted about the forepart of the shoe into one in which a single straight line seam is inserted along the shank. Preferably, inechanism for shifting the shoe transversely of the sole edge is provided to act on the work support and presser foot of the machine while clamping the work and by the use of such mechanism, a single line of stitching may be inserted merely by throwing the shifting mechanism out of operation or a double line perforation seam inserted by rendering the shifting mechanism again active.

Other features of the invention reside in certain constructions, arrangements and combinations advantages of which will be apparent from the following description taken in connection with the accompanying drawings, in which Fig. 1 is a view in front elevation of those portions only of a lockstitch outsole shoe sewing machine necessary for a complete understanding of the invention; Fig. 2 is a plan view of some of the parts of the sewing machine illustrated in Fig. 1, together with a portion of a shoe being operated upon; Fig. 3 is a sectional plan View of the work support and shifting mechanism illustrated in Fig. 2; Fig. 4 is a detail plan view illustratinga portion of the control lever for rendering the shifting mechanism inoperative; Fig. 5 is a view in left side elevation of the operating mechanism for actuating the needle and the shoe shifting devices,

indicating the positions of the parts while the needle is retracted from the work; Fig. 6 is a similar View of the same parts in positions assumed whilethe needle engages the work; Fig. 7 is a sectional view taken along the line 11 of, Fig. 5 looking in the direction of the arrows; Fig. 8 is a detail view illustrating the position of the shoe in the machine while stitching along the inner one of a double line of perforations in a shoe sole; Fig. 9 is a similar detail view illustrating the position of the shoe when stitching along the outer one of a double line of perforations; and Fig. 10

is a detail sectional view of a portion of the machine taken along the line l0lli of Fig. 1.

The illustrated machine is a curved hook needle lockstitch outsole shoe sewing machine and except as hereinafter described, is the same in construction and mode of operation as that disclosed in the patent to Ashworth No. 1,169,909 of February 1, 1916. The curved hook needle of the present machine is indicated at 2, a curved awl at 4, a rotary shuttle at 6, a work support at 8 and a presser foot at ID. The machine is also equipped with other stitch forming devices operating as more particularly described in the Ashworth patent referred to. In the operation of the machine, the awl 4 first penetrates the outsole from the under side and moves the outsole a stitch length from right to left lengthwise of the outsole edge to bring the awl perforation into line with the needle. The needle then follows the awl as the awl is retracted from the work, entering the awl perforation and withdrawing from the work with a loop of needle thread which is passed by the shuttle about a supply of locking thread contained therein. The needle, awl and other stitch forming devices are driven from a pair of simultaneously rotating sewing shafts l2 and I4 by cranks on the sewing shafts, the needle actuating crank only being illustrated at l5. The needle actuating crank carries a pitman IS, the lower end of which is pivotally connected to one arm of a bell crank lever l8 fulcrumed on a shaft 2-0 mounted at its ends in the frame of the machine. Another arm on the lever 18 is connected by means of a bent link22 to a needle supporting segment 24 rotatable on a stud 26, which stud is mounted in suitable bearings in the machine frame. The needle 2 is clamped in the segment 24 and operates in the usual manner.

Referring to Figs. 2, 8 and 9, the marginal portion of a o dyear shoe sole is indicated at 28 with an upper 30 supported on a last 32. The outwardly flaring sole attaching flange is in the usual form of a welt 34 connected to the upper and to an insole 36. The outsole 28 is cut with a shape which provides a projecting marginal portion of the extent indicated in Fig. 8 about the forepart of the shoe and a projecting marginal portion of lesser extent along one or both sides the shank of the shoe. When sewing about the forepart of the shoe, it is often desirable when the parts operated upon are of relatively thin gage, to insert stitching within widely spaced awl perforations arranged in two parallel lines, as illustrated by the dot- dash lines 38 and 40 in Fig. 2, the outsole edge being guided by a back gage 46 (Fig. 8) integrally formed on the work support. When sewing along the shank of the shoe with scant projecting marginal portions, there is insufficient space for the double line perforation stitching and accordingly, the stitching is inserted along the single outer line 48 only, theshoe being guided by contact of the upper against the forward surfaces of the work support 8,

The present machine is constructed and ar ranged to insert the double line perforation stitching by shifting the projecting marginal portions of a shoe outsole transversely of the outsole edge between alternate operations to form a zig-zag pattern and to this end, the work support 8, instead of being rigidly secured to the machine frame as in the patented construction, is mounted on a slide 42 supported in a horizontal guideway 44 extending forwardly and rearwardly of the machine. Suitable mechanism, to be described hereinafter, is provided for shifting the work support slide in the manner outlined and to cause the work, particularly When it consists of the projecting marginal portions of a Goodyear shoe outsole, to move with the work support.

The presser foot It! also is movabl with the work support while being shifted in the guideway 44 and includes a downwardly extending arm having. a horizontal pivot screw 48 passing through a rectangular bar 50 secured to a presser foot lever 54 constructed as more fully disclosed in the Ashworth patent referred to. The end of the pivot screw 48 is threaded in the arm of the presser foot in and the shank of the screw is of slightly larger diameter than the threaded end so as to provide a shoulder against which the screw may be tightened. The shank of the pivot screw passes loosely through a bearing in the bar 50 to enable the arm to swing freely about the pivot screw, the arm being held rearwardly against the back gage 48 on the work support by a spring 52 stretched between th presser foot and a hooked pin on the bar 50.

The mechanism for shifting the work support acts while the presser foot is clamping the marginal portion of the outsole when the needle and awl are disengaged from the work and comprises a rocker lever 56, best shown in Fig. 3, having an arm with a circular terminal fitting a corresponding recess in a block 58 slidingly mounted in an opening of the work support slide 42. The rocker lever is fulcrumed on a vertical bolt 60 passing through a supporting plate 62 beneath the rocker lever and having its upper end threaded into a block 64 secured by a screw 65 (Fig. 10) at on end and by a brace 66 at the other end to the main frame of the machine. The rocker lever 56 at each side of the bolt 66 is engaged by one of two tappet rods 61 and 68 slidingly mounted in upwardly extending flanges on the plate 6. The tappet rods 6? and 68 also engage surfaces 10 and 12, respectively, on a cam member rotating on a horizontal shaft 74 passing through one of the flanges on th plate 62 at one end and passing through a bearing sleeve [6 in a bracket 18- at the other end bolted to the plate 62. The sleeve 16- not only forms a bearing for the shaft 14, but a ratchet arm 80- oscillates continuously during sewing operations on a portion of the sleeve which extends inside the bracket 18. The ratchet arm is disposed adjacent the exposed surfaces of a circular disk 82' secured to a drum 84 forming the cam member.

The cam surfaces 19 and 12 are arranged on the end face of the drum 84 at different distances from the shaft 14, so that each tappet rod will engage one cam surface only. The cam surfaces are shaped to cause the tappet rods to be shifted alternately, imparting a rocking movement to the lever 56 and a forward and rearward movement to the work support.

To rotate the cam drum, the disk 82 has slidably mounted at 90 intervals about its exposed side surface two sets of spring-pressed plungers 86 and 88, those of each set being disposed alternately with those of the other set and at diametrically opposite sides of the shaft 14. The plungers 86 and 85 project into the oscillating path of the ratchet arm 80 to cause a 90 rotation of the drum for each rearward oscillation of the ratchet arm. The arm Bil has adjustably secured to it a spherically headed pin 90- surrounded by a socket at one end of an adjustable link 92, the other end of which has a socket surrounding the head of a similar pin 94 in an arm of the needle actuating bell crank lever 18. By these connections, the cam drum 84 is rotated a quarter of a revolution after the needle has retracted from the work with the loop of needle thread in each sewing cycle and before the awl penetrates the work.

W'hile sewing about the forepart of a shoe (see Fig. 2), the work support is shifted alternately forwardly and rearwardly, moving the, projecting marginal portions of the shoe outsole at the same time, the presser foot clamping the outsole against the work support while being moved. Directly after forward movement of the outsole, the awl penetrates the outsole to form a perforation for the needle in the outer line of perforations GB and after rearward movement, the awl forms a perforation in the inner line 38. After penetration of the outsol by the awl, the press-er foot releases the outsole and the awl moves it a i stitch length to bring the perforation into line with the needle. To provide clearance for the needle and awl in either forward or rearward positions of the work support and presser foot, th throats of the presser foot and work support are sufficiently enlarged to accommodate this movement.

When the shank of the shoe is reached with relatively narrow projecting marginal portions on the outsole, the forward and rearward movements of the outsole are terminated and the mechanism for shifting the work support is rendered inoperative. The Work support shifting mechanism is rendered inoperative by moving the ratchet arm 80 lengthwis of th shaft M away from the exposed surface of the disk 82 so that during its oscillating movements, the ratchet arm will not rotate the cam drum, the sleeve 16 being constructed with sufficient length to engage the eXposed surface of the disk 82 and hold it in fixed axial position. When the ratchet arm is moved along the sleeve away from the disk 82 (Figs. 4 and 7) certain of the plungers ar no longer engaged by the arm.

To move the ratchet arm lengthwise of the shaft M, the hub of the arm is formed with a radial" slot 96 into which i received a pin 98 mounted in one arm of a handle lever I fulcrumed on a pivot bolt 32 secured in an arm of the bracket 18. To hold the handle lever I00 in the position to which it is moved, the bolt I02 is surrounded by a spring washer Hi4 (see Fig. 5) acting between the arm of the bracket and a check nut I05 on the bolt. During oscillation of the ratchet arm, a bevel surface I08 on the arm, during its forward movement, depresses one ofthe spring-pressed plungers 86 or 88. During rearward movement of the ratchet arm, a cut-away portion on the arm engages the side of the plunger and rotates the cam drum. To hold the drum from rotation during forward movement of the ratchet arm and to prevent rotation when the shifting mechanism is rendered inoperative, the drum is surrounded by a brake band HE}, one end of which is secured to the bracket 18 and theother end of which is connected to a tension spring H2 stretched between the brake band and the bracket 18.

In order to prevent the work support shifting mechanism from being rendered inoperative while the work support is in its forward position, so that the narrow projecting marginal portion of the outsole along the shank of a shoe will not be held out of the path of the stitch forming devices, the plungers 86 are made longer than the plungers 88. The ratchet arm, when moved away from the disk 82, will not be disengaged from these plungers (see Fig. 7). If the handle lever I0!) is operated at a time when the work support is in its forward position, the ratchet arm will, during its forward movement, depress one of the longer plungers 86 and rotate the drum during its rearward movement to bring the work support into rearward position. Thereafter, during forward movement of the ratchet arm, the shorter plungers 88 being of insufficient length to engage the ratchet arm when moved away from the disk 82, no further rotation of the drum will occur.

It is within the concept of the invention to employ seams other than those having a zig- Zag pattern. Different patterns of continuous thread stitching may readily be inserted when the seam'is applied to the double line of perforations by making slight changes in the work support shifting mechanism of the machine, or by changing the timing of the shifting mechanism with relation to the feeding movements of the awl. It is of definite advantage to insert a seam formed in part by single-line stitching and in part by double-line stitching in order to bring the threads together along certain parts of the work and to distribute them along other parts, if continuous threads are employed so that no break occurs in the threads at a position where weakness in construction may develop during subsequent use of the work.

The nature and scope of the invention having been indicated, and a particular embodiment of the invention having been specifically described,

what is claimed is:

1. A shoe sewing machine having, in combination, stitch forming devices including a curved hook needle, a work support and a presser foot for clamping the projecting marginal portions of a shoe sole, means for causing the shoe to be fed lengthwise of the sole edge relatively to the needle, and mechanism for actuating the work support and presser foot while clamping the projecting marginal portions transversely to the sole edge to cause the needle to insert zigzag stitching along the projecting marginal portions of the sole.

2. A shoe sewing machine having, in'combination, stitch forming devices including a curved hook needle, means for clamping and feeding the projecting marginal portions of a shoe sole lengthwise of the sole edge, mechanism for relatively moving the shoe and the stitch forming devices transversely to the edge of the shoe sole between stitches to insert stitching within a double line of perforations along the projecting marginal portions of the sole, and means actuable during sewing for preventing transverse movement of the work support and presser foot to cause the stitching to change from a double line pattern into a single line seam.

3. A shoe sewing machine having, in combination, stitch forming devices including a needle, means for feeding the projecting marginal portions of a shoe sole lengthwise of the sole edge, a work support and a presser foot for clamping the projecting marginal portions of the sole, a cam drum for actuating the work support and presser foot transversely of the sole edge, and an oscillating ratchet arm for rotating the cam drum to cause the work support and presser foot to be moved first in one transverse direction and then in the other;

4, A shoe sewing machine having, in combination, stitch forming devices including a needle, means for feeding the projecting marginal portions of a shoe sole lengthwise of the sole edge, a work support and a presser foot for clamping the projecting marginal portions of the sole, a cam drum for actuating the work support and presser foot transversely of the sole edge, an oscillating ratchet arm for rotating the cam drum to cause the work support and presser foot to be moved first in one transverse direction and then in the other, and means for preventing rotation of the cam drum while the ratchet arm continues to oscillate.

5. A shoe sewing machine having, in combination stitch forming devices including a needle, means for feeding the projecting marginal portions of a shOe sole lengthwise of the sole edge, a work support and a presser foot for clamping the projecting marginal portions of the sole, a cam drum for actuating the work support and presser foot transversely of the sole edge, an oscillating ratchet arm, plungers on the cam drum projecting into the oscillating path of the ratchet arm, and means for moving the ratchet arm away from the plungers to prevent rotation of the cam drum.

6. A shoe sewing machine having, in combination, stitch forming devices including a needle, means for feeding the projecting marginal portions of a shoe sole lengthwise of the sole edge, a work support and a presser foot for clamping the projecting marginal portions of the sole, a cam drum for actuating the work support and presser foot transversely of the sole edge, an oscillating ratchet arm, plungers of alternately different lengths n the cam drum, the longer ones of which act with the ratchet arm to bring the work support into a position effective for sewing the shank of the shoe and the shorter ones of which act with the ratchet arm to bring the work support into a position effective for sewing the forepart of a shoe, and means for moving the ratchet arm away from the shorter plungers while still holding the arm in a position where the longer plungers are engaged thereby.

7. A shoe sewing machine having, in combination, stitch forming devices including a needle, mechanism for actuating the needle, means for feeding the projecting marginal portions of a shoe sole lengthwise of the sole edge, a work support and a presser foot for clamping the pro jecting marginal portions of the sole, a cam drum for actuating th work support and presser foot transversely of the sole edge, an oscillating ratchet arm for rotating the cam to cause the work support and presser foot to be moved first in one transverse direction and then in the other, and actuating connections for the ratchet arm between the needle mechanism and the arm.

8. A shoe sewing machine having, in combination, stitch forming devices including a needle, means for feeding the projecting marginal portions of a shoe sole lengthwise of the sole edge, a work support and a presser foot for clamping the projecting marginal portions of the sole, a slide on which the work support is mounted, a back gage on the work support, mechanism for shifting the work support slide transversely of the sole edge, and means for causing the presser foot to be shifted transversely of the sole edge with the back gage.

9. A shoe sewing machine having, in combination, stitch forming devices including a needle, means for feeding the projecting marginal portions of a shoe sole lengthwise of the sole edge, a work support and a presser foot for clamping the projecting marginal portions of the sole, a slide on which the work support is mounted, a back gage on the work support, mechanism for shifting the work support slide transversely of the sole edge, and spring means for holding the presser foot against the back gage to cause the presser foot to be shifted transversely of the sole edge with the work support.

10. A shoe sewing machine having, in combination, stitch forming devices including a needle, means for feeding the projecting marginal portions of a shoe sole lengthwise of the sole edge, a work support and a presser foot for clamping the projecting marginal portions of the sole, a slide on which the Work support is mounted, a back gage on the work support, mechanism for shifting the work support slide transversely of the sole edge comprising a rotating member, and a continuously oscillating ratchet arm for driving the rotating member.

11. A shoe sewing machine having, in combination, stitch forming devices including a needle, means for feeding the projecting marginal portions of a shoe sole lengthwise of the sole edge, a work support and a presser foot for clamping the projecting marginal portions of the sole, a slide on which the work support is mounted, a back gage on the work support, mechanism for shifting the work support slide transversely of the sole edge comprising a rotating member, a continuously oscillating ratchet arm for driving the rotating member, and means for moving the ratchet arm away from the rotating member to prevent transverse shifting of the work support.

12. A shoe sewing machine having, in combination, stitch forming devices including a needle, means for feeding the projecting marginal portions of a shoe sole lengthwise of the sole edge, a work support and a presser foot for clamping the projecting marginal portions of the sole, a slide on which the work support is mounted, a back gage on the work support, mechanism for shifting the work support slide transversely of the sole edge comprising a rotating member, a continuously oscillating ratchet arm, plungers of alternately different length on the rotating membar, the longer ones of which act with the ratchet arm to bring the work support into a position effective for sewing the shank of the shoe and the shorter ones of which act with the ratchet arm to bring the work support into a position effective for sewing the forepart of a shoe, and means for moving the ratchet arm away from the shorter plungers while still retaining the arm in 5 a position to engage the longer plungers.

HOMER F. SMITH.

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