CA1202231A - Method and apparatus for manufacturing woven slide fastener stringers and articles produced thereby - Google Patents

Abstract

ABSTRACT

A method and apparatus is disclosed for manufacturing a woven slide fastener stringer having a row of coupling elements woven integrally into a woven stringer tape as the latter is woven. An element-forming filamentary material is displaced away from warp threads of the stringer tape and is coiled by and around a hook which moves remotely from the warp threads without interference therewith. A woven slide fastener stringer produced by the method and apparatus is claimed in the present divisional application. It has a row of coupling elements stably fixed in position to a stringer tape by a binding warp thread system having a pattern similar to a row of sewing stitches.

Description

BACKGROUND OF THE INVENTION
Field of the invention:
The present in~ention relates to an article produced by a method of nd an apparatus for manufacturing a woven slide fastener stringer having a row of continuous filamentary coupling elements woven integrally into a stringer tape.
Prior Art Various methods and apparatus for manufacturing woven slide fastener stringers have been proposed and used. An apparatus disclosed in Japanese Laid-Open Patent Publication No.
50-36,249 published April 5~ 1975 has a rotor for coiling an element-forming filamentary material of synthetic resin in a conical orbital path around a mandrel into a row of coupling elements as they are woven into a stringer tape in synchronism with the weaving of the latter. Th~ known apparatus is complex in construction and hence needs tedious and time-consuming adjustment and maintenance.
According to another known apparatus shown in West German Laid-Open Patent Publica~ion No. 2,221,855 published November 30, 1972, an element-forming filamentary material is coiled into a row of coupling elements without using a rotor and a mandrel, the coupling elements being woven into a stringer tape as the latter is woven. The apparatus includes a rocer arm angularly movabli3 in a plane substantially parallel to the general plane of the stringer tape for moving a hook into and out of a warp shed across warp threads to coi~ the element-forming filamentary material around the hook. The hook thus arranged is likely to interfere or otherwise damage the warp threads, particularly when the apparatus operates at a relatively high speed. A small sized hook may reduce damage ~2~

to the warp threads but is apt to fail to catch the element-forming filamentary material.
SUMMARY OF THE NVENTION
It is an object of the preset invention to provide a method of manufacturing a woven slide fastener stringer having a row of continuous filamentary coupling elements woven into a stringer tape at an increased rate of production without causing warp threads to become damaged.
Another object of the pxesent invention is to provide an appara~us reducing such method to practice, which apparatus is simpie in construction and easy to maintain.
A further object of the present invention to which the present divisional application is specifically directed, is to provide a woven slide fastener stringer produced by the apparatus.
Such fastener stringer has a row of coupling elements fixed to a stringer tape with an increased degree of binding strength by means of a binding warp thread system having patterns similar to sewing stitches.
According to the invention and defining same in general terms, an element-forming filamentary material of synthetic resin, supplied to a fell of a stringer tape being woven along a longitudinal path extending between and substantially parallel to warp threads of the stringer tape, is displaced by an imgularly mo~able pusher arm out of the longitudinal path into a position outside the warp threads. A hook angularly moves alongside the warp threads to hook the element-forming filamentary material at said position and to bring the same into another position adjacent to and aligned with the fell, thereby coiling the filamentary mat~erial around a rectangular nose portion of the hook into a coupling element.

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Many other advantages, features and additional objects of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying drawings in which certain preferred embodi-ments incorporating the principles of the present invention are shown by way of illustrative example.

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BRIEF DE~/~RIPTION OF l'H Dr~AWI~G.S
FIGS. 1 an~ 2 are sc~ematic perspective views of an apparatus according to the present inventionr the views showing parts in different positions while the ap~aratus is in operation to produce a woven slide fastener stringer;
FIG. 3 is an enlarged perspective view of a portion of the apparatus ~hown in FIG. 2;
~ IG. 4 is an enlarged perspective view of a portion of the slide fastener stringer as being produced, the parts not shown being in the position of FIG. l;
FIG. 5 is an enlarged schematic plan view of a woven slide fastener stringer according to the present invention;
FIG. 6 i.s a transverse cross-sectiona~ view taken alonq line VI-~II of FIG. 5;
FIG. 7 is a longitudinal cross-sectional view taken along line VII-~7II of FIG. ~;
FIG. 8 is a view similar to FIG. 5 of another embodiment of the present invention; and FIG. 9 is a longitudinal cross-sectional view taken along line IX-IX of FIG. 8.
DETAILED DESCRIPTIO~
FIGS. 1 and 2 illustrate an ap~aratus for manufacturing a woven slide fastener stringer in accordance with the present invention. The apparatus compri.ses a ~oom 10 for progressively weaving a stringer tape 11 of warp threads 12, 13, la at a fell 15, the loom 10 ~nclu~1ing conventional heddles or a shedding means l5a shown diagrammatically for forming a Dair ~f upper and lower warp she~s 1~, 17 between the war~ threads 12, 13, 14 and for selectively moving the warP threads 12, 13, 14 up and down, a filling carrier or weft inserter 18 disposed at one edge of the warp threads 12, 13, 14 and angularly movable for inserting a ,, weft thread 19 in the upper warp shed 16 bet~een the warp ~hreads 12, 13, a reed 20 movable back and forth for beating the weft thread 1~ inserteA in the ~hea 16 against the fell 1~, an~ a knitting needle 21 reciprocably disposed at the opposite edge of the warp threads 12, 13, 14 for successively knitting loops of the weft thread 19 pro~ecting out the warp shed 1~ to form a tape selvage. The reed 20 has a plurality of longitudinal slots 2~
through which the warp threads 12, 13, 14 extend from the he~dle 15a to the fell 1~. An element-forming filamentary material of synthetic resin 23, which has a plurality of px~spective coupling head portions 47 (FI~S. 5 and 6) formed in advance thereon at equal intervals, is lnb~uced inthe lower warp shed 17 through the secvnd endmost sl~t 22a to the fell along a synthetic resin 2~ is introduced in the lower warp shed 17 through the second endmost slot 22a to the fell along a longitudinal path extending between and substantially parallel to the warp threads 12, 13f 14. The longitud;nal slot 22a through which the filamentary material 23 passes is selected on the basis of the length L (FIG. 5) of a coupling element to be formed.
The apparatus also includes a coiling means operable in synchronism with the loom 10 for coiling the element-forminq filamentary material 23 into a row of coupling elements 24 whereby the row of coupling elements 24 is woven integrallY into the stringer tape 11 as the latter is woven. The coiling means comprises a rocker arm 25 disposed at the one edge of the warp threads 12, 1~, 'L4 and rockingly movable about its one en~. As shown in FIG. 3, the rocker arm 25 has at the opposite or distal end a hook 25 including ~ head portion 26a and a nose portion 26b projecting from the head portion 26a in a direction parallel to the warp threads 12, 13, 14 and hence to the path of the filamentary material 23. The nose portion 26b is n the form of a rectangular block and has a transverse cross section which ,

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defines a space between a pair of upper and lower legs of each Coupling element 24. The head Dortion 2~a has a shape like the frustum o a pYramid defined by four slan~ed ~urfaces 27~ ~, 2~, 30. The slanted surfaces 27-30 enahle the filamen~ary material 23 to slide ~moothly thereon and over ~he no~e portion 2~b. Upon rocking movement o~ ~he rocker arm 25, the hook 26 ~oves, in a plane substantially perpendicular to the general plane of the stringer tape 11, between a first por~ion shown in ~IGS. 2 and 3 in which it is located in alignment with the fell 15 and a second portion shown in FIG. 1 in which it is located remotely from the fell 15.
The coiling means also includes an arcuate pusher arm 31 disposed ~t the opposite edge of the warp thxeads 1~, 13, 14 and angularly movable across the lower warp ~hed 17. The pusher arm 31 has a bifurcated.end portion ~2 for r~ceiving therein the elemPnt-forming filamentary ma~erial 23 having ~he equidistantly spaced prospective coupling head portions 47 tFIGS. 5 and 6).
The pusher arm 31 is actuated in timed relation LO the rockex arm 25 so that while the hook 26 is at its second pos~tion shown in FIG. 1, the bifurcated end portion 32 of the pusher arm 31 engages the element-forming filamentary material 23 and displaces it by pushing the same outside the warp threads 12, 13, 14 beyond the inclined surfac~s 28, 29 of the hook's head portion 26a.
The apparatus operates as ollows. For purpose of illustration, a cycle of the operation of the apparatus begins under the conditions shown in FIG. 1 ln which (1~ the element-forming filamentary ma~erial 23 is displace~ by the pusher arm 31 outside the warp threads 12r 1~, 14 beyond the hook 26 into hooked engagement therewith, (2! the weft ~hread 1~ inserted bY
the filling carrier 18 through the u~per warp shed 16 is ready for hooked engagement with the knitting needle 21, and (3~ the . , ... ,, . ... . , .. . .. _ . ... . ... . . . . , . , . . ~ , 2~

reed 20 is retracted in a position away from the fell 15 of the stringer tape 11 being woven. Then, the r~cker arm ~5 is actuated to move angularly in the direction indicated by the .. . .
arrow in FIG. 1 whereupon the hook 2~ moves rom the se~ond position of FIG. 1 to the first position of FIGS. 2 and 3. At the ~ame time, the reed 20 is ac~uated to move forward to beat the weft thread lg just inserte~ against the ~ell 15. During that time, the element-forming filamentary material 23 is coiled around ~he hook's nose portion 26b substantially in parallel relation to the fell 15 to thereby form a coupling element 24.
Thereafter, while the rocker arm 2~ an~ hence the hook 26 is at rest at the first position shown in FIGS. ~ and 3, the reed 20 is retracted away ~rom the fell 15, then the heddle l5a is actuated to move the warp threads 12, 13, 14 up and down across the warp sheds lh, 17, and the filling carrier 18 is again actuated to insert the weft threaa 1~ in the upper warp shed 16. After the reed 20 has beat the weft thread 19 just inserted against the fell 151 the rocker arm 25 moves angularly away from the fell 15 to bring the hook 26 into the second position shown in ~IG. 1. Simultaneously therewith, the reed 20 is moved back again to its retracte~ position. Finally, the heddle 15a is actuated to chan~e the respective positions of the warp thread~
12, 13, 14 into those shown in FIG. 1, to thereby complete a cycle of operation vf the apparatus.
FIG. 4 shows the structure of a woven slide fastener stringer being woven on the apparatus, the stringer having the row of coupling elements 24 woven integraliy into the stringer tape 11. ~he row of coupling elements 24 is fixed to the stringer tape 11 along a longitudinal edge thereof by the binding warp threads 12a, 14 running respectively along undulated paths in symmetrical patterns in such a manner as to overlie one of the , . . ^ . ..

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legs of the coupling elements ~4 and o interlace with the weft thread 19 under the other of the legs of the coupling elements 24.
With the apparatus thus arranqe~, the warp threads 12, 13, 14 are protected from interfering with or otherwise being damaged by the hook 26 because the movement of the hook ~fi is limited to take place only outside the warp threads 1~, 13, 14, with the result that the apparatus can be o~erateA at a higher speed and hence produces the woven slide fastener stringer at an inc-eased rate ~f production~
FIGS. 5-7 show an example of woven ~lide fastener stringers 33 produced by the apparatus of the present ~.
invention. The slide fastener stringef 33 comprises a ro~ of coiled coupling elements 34 formed of synthetic resin fixed to a slide fastener stringer tape 35 woven of oundation warp threads 36, 37 and a ~ingle foundation weft thread 38, the row of coupling elements 34 extending along a .longitudinal edge portion 3g of the stringer tape 35. The foundation warp threads 36 and the foundation weft thread 3~ ~ointly constitute a web portion 40 of the stringer tape 35, and the foundation warp threads 37 and the foundation weft threaa 38 ~ointly constitute the longitudinal edge portion 39 of the stringer tape 35. The warp threads 3~ are thicker than the warp threads 37. The row of coupling elements , 34 i5 secured to the stringer tape 35 by means of a binding thread system including a pair of first binding warp threads 41, 42 and a plurality of second binding warp threads 43, 44, 4~, 46.
Each of the coupling elements 34 comprises a coupling head 47 projecting transversely beyond the longitudinal edge portion 39 of the ~tringer tape 35, and a pair of uRPer and lower legs 48, 4q (FIGS. 6 and 7) extending from the couplinq head 47 in a common direction and spaced from each other vertically in a direction ~ubstantiallv perpendicular to the general plane of the . ~ ~ ~ ~ ~4 stringer tape 35. The upper and lower legs 48, 4g are blended into and interconnected by a heel portion 50 located remotely from the coupling head 47. ~he lower legs 4~ of the coupling elements 34 are mounted on the longitudinal edge portion 39 of the~stringer tape 35. The founda~tion weft threa~ 38 is inserted in double picks between adjacent coupling elements 34 so that there is a pair of picks of the foundation weft thread 38, one on each side of each of the lower legs 49 of the coupling elements 34 as shown in FIGS. 5 and 7.
The first binding warp threads 41, 42 of the binding thread systemn are disposed on the heel portions ~0 of the coupling elements 34 and are int~rlaced with every other one of the pairs of picks of the foundation ~eft thread 38 in symmetrical relation substantially with respect to the general plane of the stringer tape 35. Likewi~e, the second binding warp threads 43-46 are disposed on the upper legs 48 of the coupling elements 34 and are interlaced with every other one of the pairs of picks of the foundation weft thread 38u The warp threads 43-46 run along undulated paths in staggered relation to one another between a pair of groups of the foundation warp threads 37 spaced laterally from each other. The first bindiny warp threads 41, 42 are preferably made of elastic yarns for neatly binding the coupling elements 34 and are thicker than the warp and weft threads 43-46, 37 in the longitudinal edge portion 39 of the stringer tape 3~.
With the arrangement described above, the binding warp threads 41, 42l 43-4fi secure the row of coupling elements 34 to the longitudinal edge portion 39 of the stringer tape 3~ in substantially ~he same manner as rows of sewing stitches, and there is no weft thread extending between the upper and lower legs 48, 49 of the coupling elements 34 in the space between adjacent coupling ele~ents 34. The coupling elements 34 thus _ g _ ., .. . , .. ..... , . , . .. , _ . .... . . .. . . .. . .

~ ~4 secured have a certain degree of flexibility which is enough to follow the movement of the slide fastener stringer 33, and provide a sufficient degree of co~pling s~rength which enables : opposite rows of coupling elements to mesh with each o~her firmly against the danger of becoming accidentally separated.
Furthermore, the weft thread 38 inser~ed in double picks makes the longitudinal edge portion ~ compact ~nd resilient in struc~ure, and the ~oupling elements 34 are secured ~o ~uch lonyi~udinal edge portion 39 wi~h ~he lower legs 4~ received between respective pairs of picks of the weft thread 38 and the upper leg~ 48 biased by the binding warp threads 43~46 toward the lower legs 49. With this arrangement, the coupling element~ 34 "I .
~are strong enough to withstand not only torsional stre~s but also external forces applied thereto in a direction perpendicular to the general plane of the s~ringer ~ape 35~
Another woven ~lide fastener stringer 51 produce~ on the apparatus of the invention is hown in FIGS. 8 and 9O ~he woven slide fastener ~tringer ~1 is substantially the same as the ~tringer 33 of the foregoing embodiment with the e~eption that two out of four second binding warp threa~s 52, ~3 extend transversely across ad~acent pairs of upper legs ~4 of a row o coupling elements 55 and are interla~ed with one pick of every other one of pairs of picks of a foundation weft thread S5. Each of the binding warp threads 52, S3 has portions 57 extending between the upper legs and corresponding lower legs 5S of the coupling elemenl:s 5~ substantially normal to the general plane of the woven str~nger tape 59 of the stringer ~. With the binding warp threads 52, 53 having t~e ~ortions 57, ~he coupling elements S4 can be secured ~ore p~sitively to a long~tudinal edge port.ion 60 of the stringer tape.
Although various minor modlfi~ations ma~ be suggested by those versed in the art, it ~hould be understood that I wish . . , , . . , ", ..... . . .

to embody within the ~c~pe of the patent warranted hereon, all such embodiments as reasonably and properly ~ome within the scope of my contribution to the art.

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Claims (5)

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows.

1. A woven slide fastener stringer comprising:
(a) a woven stringer tape including a longitudinal edge portion woven of a plurality of foundation warp threads and a single foundation weft thread;
(b) a row of continuous filamentary coupling elements disposed on said longitudinal edge portion and spaced longitudinally from each other, each of said coupling elements including a coupling head projecting transversely beyond said longitudinal edge portion, a pair of first and second legs extending from said coupling head in a common direction and spaced from each other in a direction substantially perpendicular to the general plane of said longitudinal edge portion, and a heel portion located remotely from said coupling head and interconnecting one of said first and second legs to another leg of an adjacent coupling element, said first legs being mounted on said longitudinal edge portion, there being a pair of picks of said foundation weft thread, one on each side of each said first leg; and (c) a binding warp thread system fixing said row of continuous filamentary coupling elements and including at least one pair of first binding warp threads disposed on said heel portions and interlaced with every other one of said pairs of picks of said foundation weft thread in symmetrical relation substantially with respect to the general plane of said longitudinal edge portion, and a plurality of second binding warp threads disposed on said second legs and interlaced with said foundation weft thread in staggered relation to one another.

2. A woven slide fastener stringer according to claim 1, said foundation warp threads being separated into two groups spaced laterally from each other, said second binding warp threads extending between said groups of said foundation warp threads.

3. A woven slide fastener stringer according to claim 1, said second warp binding threads being interlaced with every other one of said pair of picks of said foundation weft thread.

4. A woven slide fastener stringer according to claim 1, including at least four of said second binding warp threads, two of which extend transversely across adjacent pairs of said second legs and which are interlaced with one pick of every other one of said pairs of picks of said foundation weft thread, the other two second binding warp threads being interlaced with every other one of said pairs of picks of said foundation weft thread.

5. A woven slide fastener stringer according to claim 1, said first binding warp threads comprising an elastic yarn thicker than said foundation warp and weft threads and said second binding warp threads.