GB1580250A

GB1580250A - Folded tape slide fastener stringer with securing stitches

Info

Publication number: GB1580250A
Application number: GB5366777A
Authority: GB
Original assignee: Textron Inc
Current assignee: Textron Inc
Priority date: 1976-12-28
Filing date: 1977-12-23
Publication date: 1980-11-26
Also published as: JPS5383846A; CA1074536A; DE2758355A1; BE862401A

Description

(54) FOLDED TAPE SLIDE FASTENER STRINGER WITH SECURING STITCHES (71) We, TEXTRON INC., a corporation organized and existing under the laws of the State of Delaware, United States of America, of 40 Westminster Street, Providence, Rhode Island, United States of America, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: This invention relates to slide fasteners having stringers comprising continuous coup ling elements secured between folds at the edges of tape-like supports, the interengageable head portions of the coupling elements protruding through slits in the folds.

The invention provides a stringer which includes a support member including a strip longitudinally folded at one edge and having a longitudinal row of spaced transverse slits defining looped strap portions on the one edge, said folded strip having opposite overlapping strip portions interconnected by the looped strap portions; a continuous coupling element having successive sections each including a head portion extending from a com responding slit of the slits in the one edge of the support member, and an interconnecting portion extending through a corresponding looped strap portion of the strap portions of the support member and joined with an adjacent section; and overedge stitch means on the one edge of the support member extending around the interconnecting portions and securing the opposite strip portions together adjacent the coupling element.

There may thus be provided a low cost and reliable slide fastener having a continuous coupling element in a folded edge of a carrier tape with increased strength and stability.

A slide fastener comprising such stringers can avoid the difficulty that the continuous coupling element is pushed within the fold by the slider during operation of the slider.

It will be appreciated that the stitches securing the opposite folded portions of a carrier tape together strengthen the slide fastener as well as distributing local stresses throughout the slide fastener, and that the overedge stitching substantially reinforces the strap portions of the folded tape.

The coupling element conveniently is a spiral coupling element formed from a continuous filament into successive convolutions, each convolution having one of the head per- tions and a pair of leg portions extending from the opposite sides of the head portion through the respective slit in the one edge, the interconnecting portion interconnecting one of the pair of leg portions to a leg portion of an adjacent convolution; wherein the slits are formed in the support member at an oblique angle such that opposite halves of each slit receive one of the respective pair of leg portions. The overedge stitching means may include threads passing over a folded edge d a carrier tape at an oblique angle in the same direction as the oblique angle of the slits thereby to reinforce the securement of a coupling element within the folded edge.

According to another feature of the invention, there may be provided an inner reinforcing strip between the folded halves of the carrier tape to provide reinforcement of the support tape, and this strip may itself be folded and provided with slits through which the head portions projects.

Other objects, advantages and features of the invention will be apparent from the following description of preferred embodiments as shown in the accompanying drawings.

Fig. 1 is a plan view of a slide fastener constructed in accordance with the invention.

Fig. 2 is an enlarged plan view d a broken-away portion of one stringer of the fastener of Fig. 1.

Fig. 3 is a cross-section view of the slide fastener stringer portion of Fig. 2.

Fig. 4 is a side view of the stringer portion of Figs. 2 and 3 with parts broken away.

Fig. 5 is a plan view of a section of tape used in forming the stringer of Figs. 2, 3 and 4.

Fig. 6 is an enlarged plan view od a broken-away portion of a modified slide fastener stringer.

Fig. 7 is a cross-section view of the modified stringer portion of Fig. 6.

Fig. 8 is a cross-section view similar to Fig. 7 of a variation of the modification of Figs. 6 and 7.

Fig. 9 is a cross-section view of a brokenaway portion of a second modification of the slide fastener stringer.

Fig. 10 is an enlarged cross-section view taken along line 1 1 0 of Fig. 3.

Fig. 11 is a cross-section view of a brokenaway portion of a variation of the modification of Fig. 9.

Fig. 12 is a plan view of a section of an inner strip of the modification of Fig. 9.

Fig. 13 is a cross-section view of a brokenaway portion of a third modification of the slide fastener stringer.

Fig. 14 is a cross-section view of a brokenaway portion of a variation of the modification of Fig. 13.

Fig. 15 is a cross-section view of a brokenaway portion of another variation of the modification of Fig. 13.

Fig. 16 is an enlarged plan view of a broken-away portion of a further modification of the slide fastener stringer.

Fig. 17 is a cross-section view of the stringer portion of Fig. 16.

Fig. 18 is a cross-section view of a variation of the modified stringer portion shown in Figs. 16 and 17.

As illustrated in Fig. 1, the invention is embodied in a slide fastener having planarly disposed support members, such as a carrier tape indicated generally at 30 and 32, and having continuous coupling elements, such as a spiral coupling elements indicated generally at 34 and 36, along with a slider indicated generally at 38 which is slidable along the coupling elements 34 and 36 for opening and closing the slide fastener. The tape 30 and the coupling element 34, as view in Fig. 1, form a left stringer for the slide fastener while the tape 32 and the coupling element 36 form a right stringer. The right stringer is substantially a mirror image of the left stringer; therefore only the left stringer will be described in detail hereafter.

As shown in Figs. 2, 3 and 4, the spiral coupling element 34 is formed into successive convolutions or sections from a continuous filament, such as a nylon or polyester filament, which has an oblong cross section, such as a D-shape cross section. Each convolution of the coupling element 34 includes a head por tion 40, an upper leg portion 42 extending from the upper side of the head portion 40, a lower leg portion 44 extending from the lower side of the head portion 40, and a connecting or heel portion 46 interconnecting the lower leg portion 44 to the upper leg portion of an adjoining convolution.

The support member 30 is formed from a strip 48, Fig. 5, which has a longitudinal row of transverse slits 50 formed in an intermediate section thereof to define strap portions 52 extending between opposite strip portions or halves 54 and 56 of the strip 48. As shown in Figs. 2, 3 and 4, the strip is longitudinally folded along the row of transverse slits with the coupling element 34 assembled inside of the fold such that the head portions 40 and the leg portions 42 and 44 protrude from the respective slits 50 with the interconnecting portions 46 extending within the fold beneath of the strap portions 52. The strip 48 forming the support member 30 is preferable a low cost material such as a polymer resin, paper, or the like.

The slits 50 are formed at an oblique angle of the folded edge of the tape 30 so that the leg portions 42 and 44 of each section extend from opposite halves of the respective slit 50 at points spaced longitudinally along the folded edges of the tape 30. The monofilament forming the spiral coupling element 34 is twisted such that the longest dimensions of the oblong cross section of each pair of leg portions 42 and 44 are substantially aligned with each other and with the slit 50 where the leg portions 42 and 44 exit from the slit 50. The strap portions 52 are substantially wider than slits 50 and extend generally perpendicular to the interconnecting portions 46 at an oblique angle to the folded edge of the tape 30.

Stitching means indicated generally at 58 is formed through the opposite folded halves 54 and 56 d the tape 30 adjacent to the interconnecting portions 46 of the coupling elements 34. The stitching means 58 may be any conventional stitch such as an overedge stitch formed from two threads 60 and 62 with the thread 60 passing through the strip halves 54 and 56 and around the interconnecting portion 46. The thread 60, where extending over the interconnecting portion 46, extends at an oblique angle to the folded edge of the tape 30 at about the same oblique angle that the strap portion 52 forms with the edge of the tape. The stitching means 58 can be formed through the tape halves 54 and 56 adjacent to the interconnecting portion 46 from about the middle of the tape 30 to as close as possible to the interconnecting portion 46; adjacent positions contiguous the bead formed in the folded edge of the tape by the connecting portions 46 are preferred.

The stitching means 58 securely joins the tape halves 54 and 56 together adjacent to the coupling element 34 which prevents withdrawal of the coil 34 through the slots 50 in between the tape halves by the action of the slider 38 engaging the head portions 40. With the stitch means 58 joining the tape halves 54 and 56 contiguous the bead of the tape 30 containing the interconnecting portions 46, the stitches greatly improve the performance of the slide fastener by distributing local stresses more broadly throughout the fastener body and reinforcing the longitudinal stability of coupling element. For the overedge stitching the thread 60 passing over the interconnectng portions 46 substantially reinforces the strap portions 52, thereby reducing any chance that the strap portions 52 will be torn.

Additionally, the overedge stitches offer an additional advantage in that they make operation of the slider 38 easier, particularly for slide fasteners with synthetic polymer resin tapes. As illustrated in Fig. 3 the slider flanges 64 and 66 engage the thread 60 as the slider 38 is moved in the slide fastener. The thread 60 is formed from a plurality of fibers, Fig.

10, which as the slider flanges move tend to roll making the operation of the slider easier.

In a modification shown in Figs. 6 and 7, a cord 70 is disposed within the bead at the folded edge of the tape 30 engaging the outside ob the curvatures of the interconnecting portions 46 of the coupling element 34.

Preferably the cord 70 is formed from a resilient material such as a textile thus deforming to form suitable seats 72 for the heel portions 46. The cord 70 is also held within the fold by the stitching means 58 with the thread 60 passing through the folded halves adjacent the cord 70 and connecting portions 46. The cord 70 adds to the stability of the coupling element 34 and allows the strap portions 52 to more securely hold the heel portions 46 to the tape 30 due to the resilience ob the cord 70.

As illustrated in Fig. 8 a variation of the stringer with an internal cord 70 has the planar portion of tape 30 offset and in alignment with the top side of the bead and the coupling element 34. Thus the top surface of the slide fastener is relatively smooth and does not have any beads protruding upward therefrom.

In a second modification as shown in Fig.

9 of the slide fastener, the support member 30 includes an inner strip or layer within the folded outer strip. The inner strip 73 as shown in Fig. 12 includes opposite longitudinal halves or folded portions 74 and 76 connected by strap portions 78 between slits 79 substantially the same as the folded portions 54 and 56 and the strap portions 52 between the slits 50 of the outer strip 48, Fig. 5. The slits in the inner and outer strips are aligned to receive the pairs of leg portions of the coupling element 34 in the same manner as the leg portions 42 and 44 are received in the slits 50 of the stringer portion of Figs.

24. The strap portions 78 and 52 of both the inner and outer strips extend over the interconnecting portions 46 of the coupling element 34, and the folded halves 74 and 76 of the inner strip are secured together with the outer halves 54 and 56 engaged on the outside thereof by the overedge stitching 58.

The thread 60 passes through all four layers 54, 74, 76 and 56 and on the outside of the outer strap portion 52 around the interconnecting portions 46. The double layer strip of synthetic polymer resin or the like forming the support member 30 of Fig. 9 has increased strength without greatly reducing flexibility; in single strips with increased thickness to increase strength, flexibility is greatly reduced.

In a variation shown in Fig. 11 of the double thickness strip forming the support member 30, the cord 70 is included in the folded edge engaging the heels 46 of the coupling element 34 in the manner of the modification of Figs. 6 and 7.

A third modification shown in Fig. 13 has strip portions 54 and 56 of the support member 30 reinforced by a single layer or strip 80 sandwiched between the portions 54 and 56.

The strip 80, of synthetic polymer resin or the like, on the edge adjacent the coupling element 34 abuts the heel portions 46 of the coupling element 34 and has the thread 60 of the overedge stitching 58 passing therethrough to secure the strip 80. Variations, illustrated in Figs. 14 and 15, of the stringer with reinforced strip portions include folded halves 82 and 84 of a longitudinally folded strip of similar material secured by the stitching 58 between the outer strip portions 54 and 56. The folded edge of the inner strip runs along or engages the heel portions 46 of the coupling element 34.In Fig. 15, the cord 70 is included within the folded edge of the inner strip surrounding by the threads 60 and 62; in this variation the cord 70 increases the size of the bead and reinforces the security of the stitching 58 since the cord 70 distributes stress from the thread 60 along the folded edge of the inner tape to prevent tearing of the thread 60 from the support member 30.

In a fourth modification shown in Figs. 16 and 17 of the slide fastener stringer, the strip portions 54 and 56 are secured together by a straight line of stitches 90 running adjacent to the bead formed by the heel portions 46 of the coupling element 34 within the folded edge of the strip. The straight line of stitches 90 reinforces the longitudinal stability of the slide fastener stringer as well as preventing the coupling element 34 from being pushed through the slots 50 into the center between the strip portions 54 and 56. In a variation illustrated in Fig. 18 and 19, the cord 70 is included within the bead engaging the heel portions 46 and is secured by the stitches 90.

A still further modification of the slider fastener stringer as shown in Figs. 20-22, has external textile cords 94 and 96 extending longitudinally along the outside surfaces of the strip portions 54 and 56 contiguous to the bead formed in the folded edge of the tape by the interconnecting portions 46 ob the coupling element. The stitching means 58 secures the external cords 94 and 96 as well as securing the strip portions 54 and 56 together. In Figs. 20 and 21 the thread 60 passes over the outside of the external cords 94 and 96 while in the variation od Fig. 22 the thread 60 passes through the cords 94 and 96. The cords 94 and 96 provide a longitudinal textile bearing surface for the slider flanges resulting in easier slider operation and distributing stress from the slider flanges.

A still further modification of the slide fastener stringer as shown in Figs. 16-18, has external textile cords 94 and 96 extending longitudinally along the outside surfaces of the strip portions 54 and 56 contiguous to the bead formed in the folded edge of the tape by the interconnecting portions 46 od the coupling element. The stitching means 58 secures the external cords 94 and 96 as well as securing the strip portions 54 and 56 together. In Figs. 16 and 17 the thread 60 passes over the outside of the external cords 94 and 96 while in the variation of Fig. 18 the thread 60 passes through the cords 94 and 96. The cords 94 and 96 provide a longitudinal textile bearing surface for the slider flanges resulting in easier slider operation and distributing stress from the slider flanges.

Since the invention is subject to many modifications, variations and changes in detail, it is intended that all matter contained in the foregoing specification or shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense.

WHAT WE CLAIM IS: 1. A stringer for a slide fastener compris- ing a support member including a strip longitudinally folded at one edge and having a longitudinal row of spaced transverse slits defining looped strap portions on the one edge, said folded strip having opposite overlapping strip portions interconnected by the looped strap portions; a continuous coupling element having successive sections each including a head portion extending from a corresponding slit of the slits in the one edge of the support member, and an interconnecting portion extending through a corresponding looped strap portion of the strap portions of the support member and joined with an adjacent section; and overedge stitch means on the one edge of the support member extending around the interconnecting portions and securing the opposite strip portions together adjacent the coupling element.

2. A stringer as claimed in claim 1 wherein the strip is made of a material selected from the group consisting od polymer resin and pauper.

3. A stringer as claimed in claim 1 or claim 2, wherein the coupling element is a spiral coupling element formed from a continuous filament into successive convolutions, each convolution having one of the head portions and a pair of leg portions extending from the opposite sides of the head portion through the respective slit in the one edge, the interconnecting portion interconnecting one of the pair of leg portions to a leg portion of an adjacent convolution; wherein the slits are formed in the support member at an oblique angle such that opposite halves of each slit receive one of the respective pair of leg portions and wherein the overedge stitch means includes thread means extending at an oblique angle to the one edge around the interconnecting portions in the same general direction as the oblique angle formed by the slits in the support member.

4. A stringer as claimed in claim 3 wherein the filament is of oblong cross-section and is twisted so that the longest dimensions of the cross-sections of the leg portions in each convolutions are aligned with each other and with the respective slits.

5. A stringer as claimed in any ob claims 1 to 4 including internal cord means within the folded edge of the tape engaging the interconnecting portions of the spiral coupling element 6. A stringer as claimed in any of claims 1 to 4 wherein the interconnecting portions form a bead in the tape edge, and there is external cord means secured by the overedge stitching against the bead.

7. A stringer as claimed in any of claims 1 to 6, including an inner reinforcing strip extending longitudinally between the opposite overlaying strip portions of the carrier tape and secured therein by the stitch means.

8. A stringer as claimed in claim 7 wherein the inner strip is also longitudinally folded and extends inside the folded overlaying portions of the outer strip.

9. A stringer as claimed in claim 8 wherein the inner stripl also has a longitudinal row of spaced transverse slits defining looped strap portions extending over its folded edge and the head portions of the coupling element extend from corresponding slits of the inner strip.

10. A stringer according to claim 9 when including cord means as set forth in claim 5, the cord means extending longitudinally within the folded edge of the inner strip and engaging the interconnecting portions of the coupling element.

11. A stringer according to any of claims 7 to 10 wherein the inner and outer strips are synthetic polymer strips.

12. A stringer for a slide fastener substantially as hereinbefore described with reference to and as shown in Figs. 2 to 5 and 10, or Figs. 6 to 8, or Fig. 9, or Fig. 11, or Fig. 13, or Fig. 14, or Fig. 15, or Figs. 16 and 17, or Fig. 18 of the drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. bead formed in the folded edge of the tape by the interconnecting portions 46 ob the coupling element. The stitching means 58 secures the external cords 94 and 96 as well as securing the strip portions 54 and 56 together. In Figs. 20 and 21 the thread 60 passes over the outside of the external cords 94 and 96 while in the variation od Fig. 22 the thread 60 passes through the cords 94 and 96. The cords 94 and 96 provide a longitudinal textile bearing surface for the slider flanges resulting in easier slider operation and distributing stress from the slider flanges. A still further modification of the slide fastener stringer as shown in Figs. 16-18, has external textile cords 94 and 96 extending longitudinally along the outside surfaces of the strip portions 54 and 56 contiguous to the bead formed in the folded edge of the tape by the interconnecting portions 46 od the coupling element. The stitching means 58 secures the external cords 94 and 96 as well as securing the strip portions 54 and 56 together. In Figs. 16 and 17 the thread 60 passes over the outside of the external cords 94 and 96 while in the variation of Fig. 18 the thread 60 passes through the cords 94 and 96. The cords 94 and 96 provide a longitudinal textile bearing surface for the slider flanges resulting in easier slider operation and distributing stress from the slider flanges. Since the invention is subject to many modifications, variations and changes in detail, it is intended that all matter contained in the foregoing specification or shown in the accompanying drawings be interpreted as illustrative and not in a limiting sense. WHAT WE CLAIM IS:

1. A stringer for a slide fastener compris- ing a support member including a strip longitudinally folded at one edge and having a longitudinal row of spaced transverse slits defining looped strap portions on the one edge, said folded strip having opposite overlapping strip portions interconnected by the looped strap portions; a continuous coupling element having successive sections each including a head portion extending from a corresponding slit of the slits in the one edge of the support member, and an interconnecting portion extending through a corresponding looped strap portion of the strap portions of the support member and joined with an adjacent section; and overedge stitch means on the one edge of the support member extending around the interconnecting portions and securing the opposite strip portions together adjacent the coupling element.

5. A stringer as claimed in any ob claims 1 to 4 including internal cord means within the folded edge of the tape engaging the interconnecting portions of the spiral coupling element

6. A stringer as claimed in any of claims 1 to 4 wherein the interconnecting portions form a bead in the tape edge, and there is external cord means secured by the overedge stitching against the bead.