US2263939A - Sewing machine - Google Patents

Description

w. A. WHEATON 2,263,939 SEWING MACHINE-'- Filed NOV. 13, 1939,

and

Patented Nov. 25, 1941 William A. Wheaten,

United Lynn, Mass, assignor to Shoe Machinery Corporation, Borough of Flemington, N. .L, a, corppration pt New Jersey Application November 12, 1939, Serial n 393 970 The present invention relates to sewing mar .chinesfand more particularly to a simplified and improved machine for securing the welt to the m r i ,Of a a ted upper in e narrator? of what are commonly known as pre-welt shoes In sewing the welt to the margin of an funlast: ed shoe upper, it is desirable'togather or ucker e upper, es a l e he F r o t e sh to facilitate ntting the upper over a last during the subsequent manufacture of the shoe.' T9 effeet ,a substantial puckering of the upper, it has,

heretofore been considerednecess'ary to provide the sewing machine with 'a sefiarate foraddition:- al upper feeding mechanism to .act on the upper during the formation of the stitches of the seam, form a slight told orlpucker in the upper between successive passages of the sewing needle through the work. The addition of this upper feeding mechanism, however, renders the'r'nachine more complicated both in construction and operation and also by occupying a formerly open space in proximity to the sewing point obstructs the view of the operator and increases the difficulty of properly manipulating the work to secure satisfactory results.

The object of the present invention is to provide a sewing machine which does not embody a separate upper feeding mechanism, but which nevertheless is capable of puckering the upper in a satisfactory manner during the sewing of a welt to the margin of the unlasted upper. With this object in View, the invention contemplates the provision, in a sewing machine adapted to sew the welt to the margin of an unlasted shoe upper, and comprising a work feeding instrument which pierces the work, of a tension device constructed and arranged to act on the welt so as to cause a backward displacement of the welt on the upper after each feeding movement, such displacement, in connection with the efiect produced by-the possible contraction of the tensioned welt between successive stitch holes, and the effect possibly produced by the operator in bending the upper over the work support and forcing the margin into the line oflfeed, being suf H ficient .to effect a substantial puckering 'of the upper during the formation of the stitchesof the seam.

Sewing machines adapted tosew a welt to the margin of an unlasted shoe upper usually comprise a work piercing feeding instrument in the form of either an awl or a needle, and a work clamping presser-foot which is lifted during each stitch forming cycle while the workis being fed.

. w ar ng th resen inventi n re ma ma o th s i ara i r has be n provi ed with a t na ange t a t m the melt a d f w I one, ipstmmer ldl fi .in its e i magma? t. 1 d 1 tion of tl'r welt xltending he 1 ns rume t and the ten ion 'li his portiof f the ,weltjemains under tension 11mm n? readin in t ument withq r W5 from the welt at which time, to tough the welt @1 9 uppe a e s i cl mped be ween the Press desser m a s ht apn a m r 1t., te tothe Welt y r ason .or he heavy .t ns gn t ri h i has his b k ard'motmgnt l w l Q v thfiby' nce between the ti'tch hles shor disp a e e Wel t th melt thanlweihe upper ma ita the h re ad connecting ad'acent 'stitch holes is tight;- eped ulch a h th r i a t nden ,20 tosat f e the .ls inlh as th upp ,la tled' 2 nde t nsi n this it. v

x Ti et is ed ee i k es r the no are. ment in the line'o'f feed. The pucke g e a so he ee l ien dsomew at b the an ula n 9 .i el er b h .bp tp 's ii fii the por io o Litsh to gigs .wf lia r a l ir i in? re etitepe 9 a h rifl s it win r u ar lrq si efi- Jnrmbodries th rese tinrent in asew ne d ai ne wel o h'e 1m1a ltefd itlis preferred lto arrange the We a e a; re evise 4 5 Isurf hole in the upper. Also in embodying the pres-' ent invention in a sewing machine adapted to sew the welt to the margin of an unlastedshoe' upper, it is preferred to utilize a sewing machine.

passes a pin 24 projecting from the plate l4, and midway of its ends the plate [6 is provided with a slot 26 through which passes loosely a stud 28 which screws into the plate [4. The plate I6 is forced yieldingly towards the plate M by means of a spring 30 coiled around the stud 28 and interposed between a knurled head 32 at the outer end of the stud and a washer 34 loose on the stud and bearing against the plate j 16. By rotating the screw threaded stud 28, the

spring 30 can be adjusted to cause the desired pressure to be exerted on the welt. The welt passes from the welt tension device through a which forms a chainstitch seam, and to arrange the work supporting and guiding devices in a manner to cause the chain of the seam to be laid on the upper, since it has been found that the chain side of a chainstitch seam has a tendency to gather or pucker to a slight extent the material on that side of the seam. a

, The several features of the present invention will be clearly understood from the following description taken in connection with the accompanying drawing in which a form of the invention is illustrated'as embodied'in 'a sewing machine of well-known construction, so :much only of the machine being shown as is necessary to indicate the connection of the present invention therewith.

In the drawing, Figure 1 is a view in front elei vation of a portion of a sewing machine embodying the present invention; Figure 2is. a detail sectional view of the work done on the machine; Figure 3 is a detail plan view'of the welt V guiding and tensioning device, together with its supporting bracket with which the machine is provided; Figure 4 is a viewin side'elevation of the parts shown in Figure 3, looking towards the right; Figure 5 is a view in side elevation of the same parts looking towards the left; and

The sewing machine, parts of which are illustrated in Figure 1, is provided with a work support 2, a presser-foot 4, a straight awl 6, a straight hook needle 8, a cast-off 10, and a looper l2. These parts, except for changes'in the work support and presser-foot hereinafter referred to, being constructed and arranged to operate as in the well-known Puritan sewing machine. For a full disclosure of the construction and mode of operation of a machine of this type, reference may be had to the pending ,application of Ashworth S. N. 303,522 filed November 9, 1939. f

The welt guiding and' tension device with which the machine has been provided comprises two fiat plates l4 and I6 between which the Welt passes on its way to the sewing point. The plate I4 is stationary and is formed integrally with a supporting bracket I8. The plate l4 projects horizontally from the upper end of the'bracket, the lower end of which extends at an angle to the body portion of the bracket and is secured to the 'bed plate 20 of the sewing machine by bolts passing through slots 22 in the lower end of the bracket. The plate l6 of the welt tension device is mounted upon the plate |4 and'is yieldingly forced towards the plate I4 to exert the desired frictional resistance to the travel of ;the welt between the plates. To support the plate IS on the plate l4, the plate IB is provided with a hole at its rear end through which loosely guiding opening,35 in the presser-foot and, in .order that welts of difierent widths may be properly guided and controlled, the welt tension device is provided with relatively adjustable guiding pins 36 and 38 which engage the side edges'of the welt. The pin 36 is rigid with the plate I 4 and projects through a slot 40 in the plate I6 and the pin 38 is rigid withthe plate l6 and projects through a slot 42 in the plate l4. To permit a relative adjustment of the pins 36 and 38' to accommodate welts of difierent widths, the pin 24 which supports the plate [6 at its rearQend extends through a slot 44 in the plate l4 and is adjustably secured in the slot by means of a nut 46 mounted on the projecting end of the pin and cooperating with a collar 48 on the pin to clamp'the pin in adjusted position. An adjustment of the pin 24 in the slot 44 of the plate [4 moves the plate l6 longitudinally to effect the desired adjustment of the pin 38. on the plate with relation to the, pin 36, this longitudinal movement of the plate l6 being permitted by the slot '40 in the plate l6 and the slot 42 in the plate I 4.

In'utilizing theillustrated machine to sew a vWelt to the margin of an unlasted'upper, the welt is threaded through the welt tension device and through the slot 35 in the presser-foot and the upper, indicated at 5B, is located in. the machine beneath the welt indicated at 52,'the edges of the welt and upper being accurately aligned by an edge gage indicated at 54 in'Figure 1.- During thezsewing operation, the upper is bent over the Work support 2 to cause thewelt and upper to assume as nearly as possible the relative position which they will have in the completed shoe. To facilitate this pending operation, the work support is somewhat narrower than the support ordinarily used in this type of machine, and is rounded off on its upper surface both in front of "and behind the sewing point as clearly indicated in Figure 1'. The machine formsa chainstitch seam, with the chain of the seam laid on the upper. The natural tendency of a chainstitch seam is to compress the materials more upon. the

' chain side of the seamthan on the opposite side and this fact, together with the manipulation of the upper in bending it over the work support tends to facilitate the puckering of the upper,

"especially in' sewing around the toe of the shoe.

The puckering effect resulting from the location 'of the chain of the. seam and the manipulation of the upper is, however, very slight, and the principal and substantial puckering effect produced by the machine is due to the action of the In theoperation of the pending application above referred to, the-work is fed-by the needle, which enters the work from below, passing upwardly, first through the upper and then through the welt, into the position in- 'dicated in Figure 1. At this time the work is clamped between the presser-foot and the work support, After the needle passes upwardly through the work, the presser-foot .is raised-and the needle is moved to :the left, as viewed in Figure 1, the distance of a stitch length. During this movement, the portion of the welt between the needle and the welt tension device is tensioned, the amount of tension being considerable on account of the heavy pressure exerted upon the welt by the plates of the tension device. At the end of the feeding movement, the presserfoot descends to clamp the work against the work support. The needle now withdraws and as it passes downwardly through the welt and upper, the welt is first released, and while the upper is momentarily held from movement in the line of feed by the needle, the tension to which the welt has been subjected, causes the welt to move backwardly slightly, thereby tending to displace the hole in the welt with relation to the hole in the upper. As the needle completes its downward movement, the upper as well as the welt is released, and although the welt and upper are still clamped between the presser-foot and the work support, the tension to which the welt continues to be subjected causes a further backward movement of the welt carrying the upper with it. The backward movement of the upper is, however, resisted by the friction exerted on the upper by the surface of the work support so that the welt moves further than the upper, and a slight fold is made in the upper between the last needle hole and the point where the needle next pierces the work. The work remains clamped between the presser-foot and the work support during the backward feeding movement of the needle and until the needle again passes upwardly through the work to the position indicated in Figure 1. At this time the portion of the welt between the preceding needle hole and the needle is still under some degree of tension and, as the presser-foot rises to permit the work to be fed, this portion of the welt is released and if it has been stretched to any extent, it is allowed to contract to its original condition, thereby still further shortening the distance between the last two needle holes and augmenting the puckering effect on the upper. The effect of the contraction of this portion of the welt is in any event, however, extremely slight, the substantial puckering effect on the upper being produced by reason of the strong pull exerted on the welt during the feeding movement of the needle against the resistance offered by the welt tension device, which resistance must be sufiicient to produce an appreciable backward displacement of the welt with relation to the upper during the formation of each stitch.

The nature and scope of the present invention having been indicated, and a machine embodying the invention having been specifically described, what is claimed is:

l. A sewing machine for attaching the welt to the unlasted upper of a pre-welt shoe having, in combination, a work support and a presser foot to receive between them a superposed welt and upper, the presser foot being constructed, arranged and operated to clamp, release and again clamp the work during each stitch forming and work feeding cycle, work feeding and stitch forming devices comprising a work piercing feeding instrument constructed, arranged and operated to pierce the work while clamped, to feed the work while released and to withdraw from the work after the work is again clamped, and means for effecting a substantial puckering of the upper during the formation of the stitches of the seam comprising a :tension device acting .on the welt constructed and arranged :to cooperate with the work piercing feeding instrument to produce suflicient tension on the welt during each work feeding movement to cause a backward displacement .of the welt on the upper as the piercing feeding instrument leaves the work.

2. A sewing machine for attaching the welt to the unlasted upper of a pre-welt shoe having, in combination, a work support and a presser foot to receive between them a superposed welt and upper, the presser foot being constructed, arranged and operated to clamp, release and again clamp the work during each stitch forming and work feeding cycle, work feeding and stitch forming devices comprising a work piercing feeding instrument constructed, arranged and operated to pierce the work while clamped, to feed the work while released and to withdraw from the work after the work is again clamped, and means for effecting a substantial puckering of the upper during the formation of the stitches of the seam comprising a tension device acting on the welt constructed and arranged to cooperate with the work piercing feeding instrument to produce sufiicient tension on the welt during each work feeding movement to cause a backward displacement of the welt on the upper as the piercing feeding instrument leaves the work, said work feeding instrument being arranged to enter the work from the side opposite to that on which the tension device is located.

3. A sewing machine for attaching the welt to the unlasted upper of a pre-welt shoe having, in combination, a work support and a presser foot to receive between them a superposed welt and upper, the presser foot being constructed, arranged and operated to clamp, release and again clamp the work during each stitch forming and work feeding cycle, work feeding and stitch forming devices comprising a work piercing feeding instrument constructed, arranged and operated to pierce the work while clamped, to feed the work while released and to withdraw from the work after the work is again clamped, and means for effecting a substantial puckering of the upper during the formation of the stitches of the seam comprising a tension device acting on the welt constructed and arranged to cooperate with the work piercing feeding instrument to produce sufficient tension on the welt during each work feeding movement to cause a backward displacement of the welt on the upper as the piercing feeding instrument leaves the work, said stitch forming devices being constructed and arranged to form a chainstitch seam with the chain laid on the upper.

4. A sewing machine for attaching thewelt to the unlasted upper of a pre-welt shoe having, in combination, a work support and a presser foot to receive between them a superposed welt and upper, the presser foot being constructed, arranged and operated to clamp, release and again clamp the work during each stitch forming and work feeding cycle, work feeding and stitch forming devices comprising a work piercing feeding instrument constructed, arranged and operated to pierce the work while clamped, to feed the work while released and to withdraw from the work after the work is again clamped, and means for effecting a substantial puckering of the upper during the formation of the stitches of the seam comprising a tension device acting on the welt devices cooperating therewith to form a chainstitch, and means for guiding the welt and upper with the upper at the needle side of the work whereby the chain of the seam is laid on the 5 upper.

WILLIAM A. WHEATON.

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