US2713837A - Apparatus for assembling fastener elements - Google Patents

Description

July 26, 1955 L. M. RABINOWITZ 2,713,837

APPARATUS FOR ASSEMBLING FASTENER ELEMENTS Filed Jan- 3, 1952 2 Sheets-Sheet l EN TOR.

l- BYM: 11 A g L. M. RABINOWITZ 2,713,837

APPARATUS FOR ASSEMBLING FASTENER ELEMENTS July 26, 1955 2 Sheets-Sheet 2 Filed Jan. 5, 1952 2 m IN VN TOR. BY

4 TERA/E APPARATUS FOR ASSEMBLING FASTENER ELEMENTS Louis M. Rabinowitz, Brooklyn, N. Y., assignor to Louis M. Rabrnowrtz Foundation, Inc., Dover, Del., a corporation of Delaware Application January 3, 1952, Serial No. 264,787

7 Claims. (Cl. 112-105) This invention relates to a method of and apparatus for assembling fastener elements, such as eyelets, in longitudinally spaced groups along an elongated fabric strip. More particularly, the invention method and apparatus are directed to providing a novel stitching arrangement for the fasteners, and which is cyclically repeated along the strip.

These elongated strips containing fastener elements are widely used in the clothing art, particularly in the manufacture of lingerie items such as brassieres. As presently manufactured, the eyelets are arranged in groups of two, or sometimes three, along the strip. A space'equal to twice the distance between the eyelets of a pair is left between each pair. An operator can then sever the strip midway between each pair to provide shorter strips, each of which is secured to the free end of a brassiere for cooperation with hooks on a similar strip secured to the other free end.

in the usual method of assembling the eyelets to the strip, the latter is fedlongitudinally relative to a sewing head which sews a uniform line of stitches along the strip. At predetermined spaced and uniform intervals, an eyelet is stitched to the strip, the motion of the strip being halted, stepped, and again halted during attachment of the two legs of the eyelet to the strip. To provide the larger spacing between the sets or pairs of eyelets, no eyelet is attached to the strip at every third location (when the eyelets are arranged in pairs). By severing the strip at these blank locations, shorter strips, each containing a uniformly spaced set of eyelets, are provided.

However, this arrangement has certain disadvantages. In the first place, the location of the cut is not definitely marked, so that the cutter must visually estimate the midpoint between eyelet sets. This frequently results in the short, cut strips being unequal in length, or with the eyelet set not centered therealong. Consequently, there is a possible mismating of the eyelets with their cooperating hooks when the strips are assembled to a garment. I

More importantly, the amount of material remaining on each strip on each side of the eyelet set is far more than is needed either for structural support of the attached eyelets or for adequate attachment of the strip to a garment.

The present invention overcomes these disadvantages in a novel manner by providing a predetermined sequence involving stitches of differing lengths and relative orientations. Intermediate the sets of eyelets, the seam is composed of a series of stitches characterized by a group of stitches at the cutting point including a pair of stitches of one character separated by a single stitch of a different character, thus providing a well-defined marker for the subsequent cut. The series of stitches between eyelet sets is preferably greater in length than the series of stitches securing the eyelets of each set to the strip, but substantially less than twice the spacing of the individual eyelets of each set.

nited States Patent ice The invention arrangement thus provides the distinct advantages of first, providing a definite marker for the subsequent cutting and which is distinct and outstanding from the immediately adjacent stitches, and, second, greatly reducing the length of fabric needed for a given number of eyelet sets. All this is effected solely by the stitching operation by varying the character of the stitches at preset intervals along the strip.

For an understanding of the invention principles, reference is made to the following detailed description of a typical embodiment thereof as illustrated in the accompanying drawing.

In the drawing:

Fig. l is a partial plan view of cyclical control apparatus for effecting the invention;

Fig. 2 is a vertical sectional view of the apparatus, on the line 2-2 of Fig. 1;

Fig. 3 is a partial elevation view of mechanism, synchronized with the apparatus of Fig. l, for laterally shifting a needle or sewing head relative to the strip and at timed intervals;

Fig. 4 is a partial plan view of an eyelet strip formed by the invention method and apparatus and before cutting; and

Fig. 5 is an axial sectional view through a brake mechanism for a strip driving roll included in the apparatus of Figs. 1 and 2.

In accordance with the invention method, as applied to a strip 10, such as shown in Fig. 4, in which the eyelets are arranged in spaced pairs inserted laterally between overlappingedges, the sequence of stitching is as follows. Beginning with the leading leg 13 of the first eyelet 15 inserted between the lapped strip edges, the strip or tape is held fixed against longitudinal movement while the sewing head is reciprocated twice laterally of the strip to make a dual lateral or tack stitch 16 in advance of leg 13 to fix the eyelet against movement in one direction longitudinally of the strip. The sewing head then remains laterally fixed while the strip is stepped longitudinally in a sequence involving a long step, a short step substantially one-half the long step, and a second long step. This forms a long stitch 17 binding leg 13 to the strip, a short stitch 18 between leg 13 and trailing leg 14 and a long stitch 21 binding leg 14 to the strip.

'Next, the tape remains stationary while the sewing head is reciprocated twice laterally of the strip to form another dual tack stitch 22 fixing the eyelet against movement in the opposite direction along strip 10.

With the sewing head laterally fixed, the strip is now advanced, in a series of short steps, to the position of the leading leg 13 of the next eyelet, and the next eyelet is positioned in the strip. For example, eight short steps may be given the strip in a typical practical embodiment. This forms a seam comprising a series of short stitches 23 uniting the lapped strip edges between the eyelets of one pair. The second eyelet is then stitched to the strip in the same sequence of lateral and longitudinal stitching as described in the immediately preceding paragraph, primed corresponding reference characters being used.

The novel cut line marking is now provided in the following manner and following the formation of the tack stitching securing the trailing leg 14' of the second eyelet 15' to the strip. The sewing head is maintained fixed in alignment with the seam. The strip is advanced three short steps to form three short stitches 24 (a different number of short stitches may be used if desired). Next, the strip is given a long step, followed by a short step and a second long step. This forms two long stitches 26, 27 separated by a short stitch 20. The strip is then advanced three short steps to the position of the leading,

leg ofthe first eyelet of the next pair, forming three short.

stitches 2S, and the described cycle of steps is repeated.

The cutting line is thus clearly indicated by a short stitch intermediate two pairs of eyelets. This short stitch is easily located, as it has a long stitch 26, 27 on each side, and the long stitches are made prominent by the series of short stitches 24 and 28 separating each long stitch from the adjacent pair of eyelets.

Figs. 1, 2 and 3 illustrate a preferred cycle control and strip stepping apparatus, according to the invention, for drawing strip 10 past a sewing head (not shown). The eyelet feeding mechanism may be of a conventional type known to the art, and has not been illustrated as it forms no part of the present invention.

Strip 10 is drawn past the sewing head by a knurled roller fixed to a shaft 31 rotatably mounted in a frame 30. An idler roller 32 is rotatably mounted on a spring biased arm 33 having a hub 34 oscillatable on a stub shaft 36 secured to frame 30. Roller 32 presses the tape 10 against stepping roller 25 for frictional drawing of strip 10. Shaft 31 and drive roller 25 are stepped by a ratchet and pawl mechanism, generally indicated at 35, and including a ratchet wheel 37 fixed to shaft 31 and driven by the cycle control and stepping mechanism.

The latter includes a main driving pinion 41, rotated by a driving motor (not shown) and driving a gear 42 pinned to one end of a shaft 43 rotatable in frame 30. The opposite end of shaft 43 has fixed thereon a pinion 44 driving a gear 46 secured on one end of a short shaft 47 rotatable in a bearing 48 on frame 30. The opposite end of shaft 47 has fixed thereon a gear driving a gear pinned to a control cam 50 freely rotatable on shaft 43.

A bracket 51 mounted on a transverse member 39 of frame 30 supports a stationary arm 52 on which is pivoted a substantially upright arm carrying, intermediate its ends, a roller cam follower 53 engaging cam 50. The upper end of arm 55 is offset laterally, as at 54, roller 53 projecting laterally from this offset portion. In alignment with offset 54 is an adjustable stop 56 mounted on a bracket 57 on frame member 39 adjacent bracket 51. A tension spring 58, extending between the free end of arm 55 and a bolt 59 secured to a part of frame 30, biases arm 55 to maintain roller 53 engaged with cam 50, stop 56 acting as a limit for outward displacement of arm 55.

A slot 61 formed intermediate the ends of arm 55 adjustably receives a bolt 62 securing one end of a connecting arm 63 to arm 55. The opposite end of arm 63 is pivotally connected to a crank 64 freely oscillatable on shaft 31. Crank 64 pivotally supports a pawl 65 biased by a tension spring 69 into engagement with ratchet 37. Oscillation of crank 64 thus drives ratchet 37, shaft 31, and roller 25. vented by a pawl 66 pivotally mounted on frame 30 and biased by a spring 67 to engage ratchet 37.

Back-lash of roller 25 is prevented by the friction drag or brake mechanism shown in Figs. 1 and 5. This mech-,

anism includes a flanged hub 71 having a friction disc 72 secured thereto and engaging the face of roller 25, the disc 72 having an aperture receiving the end of shaft 31 for centering. A second hub 73 is mounted on the end of a stud 74 secured in frame 30, being held against rotation by studs 76 extending through the frame and threaded into the flange of hub 73. Pins 77 secured in hub 71 and extending slidably through hub 73 restrain hub 71 from rotation. A coil spring 78 seated on both hubs biases hub 71 toward roller 25, the frictional drag being adjustable through stud 74.

The motion of roller 25 in drawing strip 10 longitudinally through the sewing head is controlled, as to timing and amount, by the cam 50 which operates pawl and ratchet mechanism 35 through movement of roller 53 and thus of arm 55. For this purpose, cam 50 is provided with a circumferential series of camming surfaces, each either projecting or recessed relative to a median circle concentric with shaft 43. These depressions and recesses extend substantially equal distances from the median circle.

Counter-rotation of ratchet 37 is pre- When cam roller 53 engages a surface of cam 50 coincident with the median circle, no motion is imparted to knurled roller 25 and the strip 10 idles. When the cam follower 53 engages a projecting cam surface, lever 55 is swung counterclockwise, causing pawl 65 to move ratchet 37 through an angle corresponding to one ratchet tooth, the pawl 65 slipping back to engage the next tooth when cam follower 53 returns to the median circle. If, now, follower 53 rides into a recessed cam surface, pawl 65 moves back another tooth. If roller 53 then returns to the median circle, ratchet 37 is advanced the space of one tooth but, if the recess is followed by a projection,

- ratchet 37 is advanced the space of two teeth.

The motion of the drive mechanism is correlated with the reciprocation of the sewing needle so that a one tooth advance of ratchet 37 steps roller 25 sutficiently to move strip 10 the length of a short stitch between successive operations of the needle. A two tooth advance of ratchet median circle of cam 50. At this time, the sewing head is reciprocated laterally of strip 19 by the mechanism shown in Fig. 3. This mechanism includes a worm 81 driven by the same means driving pinion 41 and in synchronism with the pinion.\ Worm 81 drives a worm gear 82 on a shaft 83 and fixed to a face cam 80. Face cam 80 has a generally circular cam groove 84 in which rides a roller cam follower 85 rotatably mounted on an arm 86. The latter is secured by suitable linkage (not shown) to the sewing head. When roller 85 rides on any of the lobes 87a, 87b, 870, or 87a of groove 84, the

- cam 50 completes one cycle.

sewing head is shifted laterally of strip 10, between successive needle strokes, to form the lateral stitches 16, 22. It should be noted that cam rotates twice as fast as cam 50 and thus goes through two cycles while Also, the first and second pairs are much nearer in one direction around cam groove 84 than they are in the opposite direction. The reason for these provisions will be made clear in the following description of the operating cycle.

In describing the operation of cams 50 and 3f the stitching sequence previously described for Fig. 4 will be used. Just as the lateral stitch 16 is to be formed, cam roller 53 will engage median circle 90 of cam 50 at the point A, cam 50 rotating in the direction of arrow 59.

, At the same time, roller cam follower will be at the point A of groove 84 of cam 80, which latter rotates in the direction of arrow 89.v

As roller 53 moves along circle 90, ratchet 37 and knurled roller 25 are held stationary. During this time,

. roller 85 will ride over lobes 87a, 87b in succession, resulting in the sewing head being reciprocated back and forth laterally of strip 10 twice to make the dual lateral stitch or tack stitch 16. During the latter part of this motion, roller 53 rides into depression 92:: of cam 50, causing pawl 65 to slip back over one tooth of ratchet 37.

Roller 53 now rides up on the double (effective) height projection 93a, causing pawl 65 to advance ratchet 37 two teeth, while roller 85 moves along the circular part of track 84, holding the sewing head laterally fixed. Strip 10 is advanced the length of a long stitch between successive needle strokes to form long stitch 17. Roller 53 then drops back to median circle 96 and then rides up normal height projection 94a, advancing ratchet 37 and roller 25 one step to form short stitch 18. Roller 53 then rides into recess 92b and up double height projection 93b to advance roller 25 and strip 10 two steps to form long stitch 21. Roller 53 then drops back to circle so that pawl 65 slips back over one ratchet tooth.

At this time, roller 85 is about to ride onto lobe 870. Hence, while the strip 10 remains stationary as a result of cam follower 53 riding along median circle 90 of cam 54 the sewing head is again given two reciprocations laterally of the strip to form the tack stitches 22. As roller 85 returns from lobe 87:1, to the circular part of track 84, roller 53 is about to engage the first of a series of eight normal height projections 94b to correspondingly effect stepping of strip to form the series of eight short stitches 23.

As roller 53 returns from the last projection 94b to circle 90, roller 85 again rides onto lobe 87a, and the tack stitch 16' is formed while strip 10 remains idle. Vvhen roller 53 leaves lobe 87b, roller 53 has ridden into depression Me. As'roller 53 rides up onto double height projection 930, long stitch 17' is formed, followed by short stitch 18 as roller 53 rides over projections 940. When roller 53 rides into depression 92d and over projection 9301' to return to circle 90, long stitch 21' is formed. While roller 53 rolls along circle 90, roller 85 again rides over lobes 87c, 87d to form the tack stitch 22.

The apparatus is now about to form the series of stitches separating the first eyelet group from the second eyelet group and providing the cutting line mark or indication. circular part of track 84 from lobe 87d to lobe 87a. As roller 53 successively rides over the three short projections 94d, the three short stitches 24 are formed. Roller 53 now rides into depression 922 and up over projection 932 to form the long stitch 26. Then roller 53 rides over projection 94:: to form the short cut mark stitch 20. The succeeding long stitch 27 is formed as roller 53 rides into depression 92 and over projection 93 The short stitches 28 then are formed as roller 53 successively engages the projections 94 after which the described cycle is repeated.

The invention method and apparatus thus form a novel eyelet strip in which there is a saving in materials as compared to such strips as previously formed. Additionally, a definite and clearly defined cut mark is provided by a short stitch separating two long stitches which are, in turn, separated from each eyelet group by series of short stitches.

While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the invention principles, it will be understood that the invention may be otherwise embodied without departing from such principles.

What is claimed is:

1. For the manufacture of a continuous fastener strip in which fasteners are inserted at spaced intervals along the strip and between overlapped longitudinal portions of the strip and secured in place by a longitudinal stitched seam uniting such overlapped portions, the fasteners being arranged in spaced groups each including at least two fasteners, and the seamed strip being later severed between fastener groups to provide shorter strips each containing one group of fasteners; apparatus for drawing said strip longitudinally relative to a sewing head to form said seam comprising, in combination, a driven element engaged with the strip and operable to draw the same longitudinally past the sewing head, a control cam, dn'ving means for said cam, a cam follower engaged with said cam, and stepping means interconnecting said cam follower and said element and operable to step said element responsive to movement of said cam follower by said cam, said cam having first cam follower moving surfaces constructed to impart a relatively short motion to said follower to correspondingly step said element a relatively short distance to form a relatively short stitch in the seam, second cam follower moving surfaces constructed to impart a relatively long motion to said follower to correspondingly step said element a relatively long distance to form a relatively long stitch in the seam, and cam follower idling surfaces separating said moving surfaces, the surface of said cam engaged by said follower when the sewing head is adjacent a portion of the strip During this time, roller 85 rides along the between fastener groups comprising a series of adjacent follower moving surfaces including a moving surface of one type engaged with the follower when the sewing head is substantially at the mid point between fastener groups and at least one moving surface of the other type on each side of the moving surface of said one type, to form a marking stitch substantially at the mid point between fastener groups with the marking stitch differing substantially in length from the stitches of said series immediately adjacent thereto.

2. For the manufacture of a continuous fastener strip in which fasteners are inserted at spaced intervals along the strip and between overlapped longitudinal portions of the strip and secured in place by a longitudinal stitched seam uniting such overlapped portions, the fasteners being arranged in spaced groups each including at least two fasteners, and the seamed strip being later severed between fastener groups to provide shorter strips each containing one groups of fasteners; apparatus for drawing said strip longitudinally relative to a sewing head to form said seam comprising, in combination, a driven element engaged with the strip and operable to draw the same longitudinally past the sewing head, a control cam, driving means for said earn, a cam follower engaged with said cam, and stepping means interconnecting said cam follower and said element and operable to step said element responsive to movement of said cam follower by said cam, said cam having first cam follower moving surfaces constructed to impart a relatively short motion to said follower to correspondingly step said element a relatively short distance to form a relatively short stitch in the seam, second cam follower moving surfaces constructed to impart a relatively long motion to said follower to correspondingly step said element a relatively long distance to form a relatively long stitch in the seam, and cam follower idling surfaces separating said moving surfaces, the surface of said cam engaged by said follower when the sewing head is adjacent a portion of the strip between fastener groups comprising a series of adjacent follower moving surfaces including a first moving surface engaged with the follower when the sewing head is substantially at the mid point between fastener groups and at least one second moving surface on each side of said first moving surface, to form a relatively short cut marking stitch substantially at the mid point between fastener groups.

3. For the manufacture of a continuous fastener strip in which fasteners are inserted at spaced intervals along the strip and between overlapped longitudinal portions of the strip and secured in place by a longitudinal stitched steam uniting such overlapped portions, the fasteners being arranged in spaced groups each including at least two fasteners, and the seamed strip being later severed between fastener groups to provide shorter strips each containing one group of fasteners; apparatus for drawing said strip longitudinally relative to a sewing head to form said seam comprising, in combination, a driven element engaged with the strip and operable to draw the same longitudinally past the sewing head, a control cam, driving means for said cam, a cam follower engaged with said cam, and stepping means interconnecting said cam follower and said element and operable to step said element responsive to movement of said cam follower by said cam, said cam having first cam follower moving surfaces constructed to impart a relatively short motion to said follower to correspondingly step said element a relatively short distance to form a relatively short stitch in the seam, second cam follower moving surfaces constructed to impart a relatively long motion to said follower to correspondingly step said element a relatively long distance to form a relatively long stitch in the seam, and cam follower idling surfaces separating said moving surfaces, the surface of said cam engaged by said follower when the sewing head is adjacent a portion of the strip between fastener groups comprising a series of adjacent follower moving surfaces including a moving surface of one type engaged with the follower when the sewing head is substantially at the mid point between fastener groups, at least one moving surface of the other type on each side of the moving surface of said one type, and a plurality of moving surfaces of said one type extending from each of said last-named moving surfaces of said other type, to form a marking stitch substantially at the mid point between fastener groups, with the marking stitch differing substantially in length from the stitches of said series immediately adjacent thereto, and with such immediately adjacent stitches differing substantially in length from the remaining stitches of the seam portion between fastener groups.

4. For the manufacture of a continuous fastener strip in which fasteners are inserted at spaced intervals along the strip and between overlapped longitudinal portions of the strip and secured in place by a longitudinal stitched seam uniting such overlapped portions, the fasteners being arranged in spaced groups each including at least two fasteners, and the seamed strip being later severed between fastener groups to provide shorter strips each containing one group of fasteners; apparatus for drawing said strip longitudinally relative to a sewing head to form said seam comprising, in combination, a driven element engaged with the strip and operable to draw the same longitudinally past the sewing head, a control cam, driving means for said cam, a cam follower engaged with said cam, and stepping means interconnecting said cam follower and said element and operable to step said element responsive to movement of said cam follower by said cam, said cam having first cam follower moving surfaces constructed to impart a relatively short motion to said follower to correspondingly step said element a relatively short distance to form a relatively short stitch in the seam, second cam follower moving surfaces constructed to impart a relatively long motion to said follower to correspondingly step said element a relatively long distance to form a relatively long stitch in the seam, and cam follower idling surfaces separating said moving surfaces, the surface of said cam engaged by said follower when the sewing head is adjacent a portion of the strip between fastener groups comprising a series of adjacent follower moving surfaces including a first moving surface engaged with the follower when the sewing head is substantially at the midpoint between fastener groups, at least one second moving surface on each side of said first moving surface, and a plurality of first moving surfaces extending from each of said last-named second moving surfaces, to form a relatively short cut marking stitch substantially at the midpoint between fastener groups, a relatively long stitch on each side of the marking stitch, and relatively short stitches between each of such relatively long stitches and the adjacent fastener,

5. For the manufacture of a continuous fastener strip in which fasteners are inserted at spaced intervals along the strip and between overlapped longitudinal portions of the strip and secured in place by a longitudinal stitched seam uniting such overlapped portions, the fasteners being arranged in spaced groups each including at least two fasteners, and the seamed strip being later severed between fastener groups to provide shorter strips each containing one group of fasteners; apparatus for drawing said strip longitudinally relative to a sewing head to form said seam comprising, in combination, a driven element engaged with the strip and operable to draw the same longitudinally past the sewing head, a control cam, driving means for said cam, a cam follower engaged with said cam, and stepping means interconnecting said cam follower and said element and operable to step said element responsive to movement of said cam follower by said cam, said cam having first cam follower moving surfaces constructed to impart a relatively short motion to said follower to correspondingly step said element a relatively short distance to form a relatively short stitch in the seam, second cam follower moving surfaces constructed to impart a relatively long motion to said follower to correspondingly step said element a relatively long distance to form a relatively long stitch in the seam, and cam follower idling surfaces separating said moving surfaces, mechanism operable to shift the sewing head laterally of the strip to form a lateral stitch therein, a second cam for operating said mechanism and driven by said driving means in timed relation with said control cam, said second cam having spaced camming surfaces effective to operate said mechanism at spaced intervals and one of said camming surfaces being operably positioned each time the sewing head is adjacent either side of a fastener, said cam follower being engaged with an elongated idling surface each time one of said camming surfaces is so operably positioned, whereby said apparatus is thereupon conditioned to form a lateral stitch on each side of each fastener.

6. For the manufacture of a continuous fastener strip in which fasteners are inserted at spaced intervals along the strip and between overlapped longitudinal portions of the strip and secured in place by a longitudinal stitched seam uniting such overlapped portions, the fasteners being arranged in spaced groups each including at least two fasteners, and the seamed strip being later severed between fastener groups to provide shorter strips each containing one group of fasteners; apparatus for drawing said strip longitudinally relative to a sewing head to form said seam comprising, in combination, a driven element engaged with the strip and operable to draw the same longitudinally past the sewing head, a control cam, driving means for said cam, a cam follower engaged with said cam, and stepping means interconnecting said cam follower and said element and operable to step said element responsive to movement of said cam follower by said cam, said cam having first cam follower moving surfaces constructed to impart a relatively short motion to said follower to correspondingly step said element a relatively short distance to form a relatively short stitch in the seam, second cam follower moving surfaces constructed to impart a relatively long motion to said follower to correspondingly step said element a relatively long distance to form a relatively long stitch in the seam, and cam follower idling surfaces separating said moving surfaces, mechanism operable to shift the sewing head laterally of the strip to form a lateral stitch therein, a second cam for operating said mechanism and driven by said driving means in timed relation with said control cam, said second cam having spaced camming surfaces effective to operate said mechanism at spaced intervals and one of said camming surfaces being operably positioned each time the sewing head is adjacent either side of a fastener, said cam follower being engaged with an elongated idling surface each time one of said camming surfaces is so operably positioned, whereby said apparatus is thereupon conditioned to form a lateral stitch on each side of each fastener, the surface of said control cam engaged by said follower when the sewing head is adjacent a portion of the strip between fastener groups comprising a series of adjacent follower moving surfaces including a first moving surface engaged with the follower when the sewing head is substantially at the mid point between fastener groups and at least one second moving surface on each side of said first moving surface,

to form a relatively short cut marking stitch substantially at the mid point between fastener groups and a relatively long stitch on each side of the marking stitch.

7. For the manufacture of a continuous fastener strip in which fasteners are inserted at spaced intervals along the strip and between overlapped longitudinal portions of the strip and secured in place by a longitudinal stitched seam uniting such overlapped portions, the fasteners being arranged in spaced groups each including at least two fasteners, and the seamed strip being later severed between fastener groups to provide shorter strips each containing one group of fasteners; apparatus for drawing said strip longitudinally relative to a sewing head to form said seam comprising, in combination, a driven element engaged with the strip and operable to draw the same longitudinally past the sewing head, a control cam, driving means for said earn, a cam follower engaged with said cam, and stepping means interconnecting said cam follower and said element and operable to step said element responsive to movement of said cam follower by said cam, said cam having first cam follower moving surfaces constructed to impart a relatively short motion to said follower to correspondingly step said element a relatively short distance to form a relatively short stitch in the seam, second cam follower moving surfaces constructed to impart a relatively long motion to said follower to correspondingly step said element a relatively long distance to form a relatively long stitch in the seam, and cam follower idling surfaces separating said moving surfaces, mechanism operable to shift the sewing head laterally of the strip to form a lateral stitch therein, a second cam for operating said mechanism and driven by said driving means in timed relation with said control cam, said second cam having spaced camming surfaces effee tive to operate said mechanism at spaced intervals and one of said camming surfaces being operably positioned each time the sewing head is adjacent either side of a fastener, said cam follower being engaged with an elongated idling surface each time one of said camming surfaces is so operably positioned, whereby said apparatus is thereupon conditioned to form a lateral stitch on each side of each fastener, the surface of said control cam engaged by said follower when the sewing head is adjacent a portion of the strip between fastener groups comprising a series of adjacent follower moving surfaces including a first moving surface engaged with the follower when the sewing head is substantially at the mid point between References Cited in the file of this patent UNITED STATES PATENTS 1,259,996 Kinder Mar. 19, 1918 1,742,221 Roseman Jan. 7, 1930 1,801,570 Roseman Apr. 21, 1931 1,905,504 Roseman Apr. 25, 1933 2,034,689 Alberts Mar. 24, 1936 2,067,371 Allis Jan. 12, 1937 2,089,551 Hand Aug. 10, 1937

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