[1]United States Patent Office 3@487@510 3,487,510 SLIDE-FASTENER ASSEMBLY AND METHOD OF MAKING SAME Alfons Friihficb, Essen, Germany, assignor to OptiHolding A.G., Glarus, Switzerland, a corporation 5 of Switzerland Filed Mar. 1, 1967, Ser. No. 619,833 Claims priority, application Germany, Mar. 3, 1966, 0 11,484, 0 11,488 Int. Cl. A44b 19100 10 U.S. Cl. 24-205.1 18 CWms ABS TRACT OF THE DISCLOSURE Met h(>d of making a. slide-fastener assembly and the 1,5 slide -fastener structure made thereby wherein a pair of mati ngly interconnected and separable slide-fastener halv es are each provided with a respective fabric tape and a helic oidal or meandering coupling element disposed along one edge of the tape, whereby the tape is composed at 20 least in part of a shinkable material and bas a row of ope nings receiving the heads of the coupling elements and is thereafter shrunk to hug these heads and anchor the coupling elements to the tapes. Shrinkage is effected by heat (when the fabric is composed of thermoplastic 25 thre ads) and/or by chemical treatment (when natural fiber s are used). Shrinkage in the weft or transverse directi on of the fabric is greater than that in the longitudinal or wrap direction and the weft threads between the openings are provided with formations serving as 30 stops for the warp threads bordering the openings. The ope nings are punched from the fabric or formed by omission of corresponding warp threads in the weavin.- process. A marginal portion of the fabric band adjoining the row of openings is tumed about the coupling eleme,t 35 -and can be stretched thereon to retain the coupling element at least in part by the spring-back force of the heattreat ed thermoplasic threads. 40 My present invention relates to an improved slidefaste ned assembly and method of making same and, more parti cularly, to a slide-fastener arrangement wherein a pair of slide-fastener halves are each provided with a coup ling element, matingly enga.-eable with the coupling 45 elem ent of the other slide-fastener half, extending along one edge of a support tape and affixed thereto, whereby a slider can be &awn along the coupling elements to connect and disconnect them throughout the length of the slide fastener. 50 Slide -fastener assemblies conventionally have been prov ided with couplin.- elements consisting of spacedapart coupling bodies or chains of coupling heads which are attached to the edge of a support tape by one or more secu ring techniques. Thus it is common, when a mean- oa deri n-type coupling element or a helicoidal-coil coupling elem ent is employed, to stitch the couplin.a elements directl y to a fabric or foil tape inwardly of the coupling head s which are adapted to be interleaved with the coupling beads of the metallic slide-fastener element. Other 6( tech niques f(>r attaching the coupling elements to the tape include the use of a -filler cord extending along the flank s of a continuous couplin- elernent and stitched betw een the coupling bodies to the suppc>rt fabric. In still other arrangements, thermoplastic coupling elements 65 are thermally fused to the tape, or adhesives are emPatented Jan. 6, 1970 2 ployed to join the coupling elements to the respective support bands. When the coupling element is constituted by a chain of discrete coupling bodies, similar systems including the use of filler cords or involving the crimping of the coupling body to the tape may be employed effectively. The term coupling element as used here is intended to designate continuous coupling chains which are molded, embossed, stamped or extruded from a synthetic-resin material and which preferably are generally helicoidal or meandering in configuration (see, for example, U.S. Patent No. 3,136,016) for the present purposes; however, the principles involved pertain also to a series of individual coupling bodies which are spaced apart alon- the edge of the support tape so as to appear as a c(>upling chain. The aforementioned conventional methods of affaching the coupling elements to the respective tapes, along the proximal edges thereof, of a slide fastener, are disadvantageous in many respects. For example, adhesives and thermal-welding techniques increase the stiffness of the slide fastener wbile sewing methods, whereby the stitching needle must pass rapidly between the coupling head close to the edge of the tape, frequently reduce the strength of the latter at precisely those regions at whic@h the coupling element is joined to its support. Furthermore, the coupling elements themselves must be designed to accommodate the stitching means while special sewingmachines and -uides must be provided to assure proper positioning of the coupling elements on the tapes. Considerable skill is required for many operations whereby the coupling elements are attached to the tapes with increased labor cost and a greater tendency toward defects. It is, therefore, the principal object of the present invention to provide an improved method of making slidefastener assemblies of the aforedescribed type whereby the connection of the coupling elements to the respective support tapes is simplified and facilitated. A further object of my invention is to provide an improved slidefastener assembly in which the fastening of the coupling elements to the support tape is reinforced or strengthened relative to conventional attachment methods and whereby the coupling heads are precisely and immovably fixed in position along the tape. Still another object of my invention is to provide a slide-fastener assembly and method of making same whereby dislocation of the coupling heads can be limited and the manufacture of the assembly simplified and im-proved. 1 have now found that it is possible to secure coupling elements of slide-fastener assemblies to the respective tapes in an accurate and relatively simple manner, without weakening of the junction and even without the relatively complex means hitherto necessary for such purposes, by providing the fa:bric support tape, usually -proximal to the edge at which the coupling element is to project but inwardly of the marginal i)ortion of the tape at this edge, with a row of openings @spaced apart a frequency sufficient to enable the head of the coupling element to pass through these openings) extending parallel to this edge. The tape or band is, advantageously, provided with shrinka:ble filaments or threads at least extending transversely to this row of openings and interconnecting the marginal portion of the tape with the remainder thereof, whereby the coupling element is mounted upon the tape with coupling heads passin.- through the respective openin.-s,
[2]3 and the assembly is thereafter treated to shrink at least the threads bordering the opening and seize the coupling element at the necks thereof which pass through the openings. Thus, the support tape is composed of a shrinkable material, i.e. is woven or knitted from shrinkable threads of the character described or contains shrinkable filaments together with, or incorporated in generally nonshrinkable threads. Alternatively, the shrinkable thread may be interspersed with nonshrinkable threads or disposed only between the openings while the balance of the threads constituting the fabric are of a nonshrinkable character. Upon shrinkage of the tape, therefore, the threads defining the openings are tightened about and hug the heads of the coupling element, while retaining the coupling element. According to a further feature of this invention, th-support tape is composed of a fabric whose threads are shrinkable in the longitudinal (i.e. warp) direction (i.e. parallel to the row of openings and the coupling elements) as well as transversely of the row of openings. In this case, the stronger shrinkage is preferably in the transverse (i.e' weft) direction. The openings may, as indicated earlier, be formed by omitting one or more threads in the weaving operation or by distending or loosening a row of I ops in a knitting system. ,9 Advantageously, the marginal portion of the support tape is of a width sufficient to enable the tape to be tumed back along the row of openings so that the marginal portion of the tape overlies the coupling elements and can be affixed thereto so as to embrace the couplinelements between an underlying layer of fabric formed by the body of the tape and an overlying layer constituted of this marginal portion. The shrinkage can be effected by any conventional means so that, for example, wben the shrinkable threads are composed of natural fibers shrinkable in water or chemical solutions, the shrinking operation can involve an immersion, spraying and/or steam treatment of the tape; it is also desirable, and a preferred realization of this invention, to constitute the shrinkable threads of a thermally contractile fiber or filament, such as nylon, wbich shrinks upon heating to hug and conform to the heads of the slide fastener. The latter preferably are of the continuous type mentioned above, i.e. meandering or helicoidal, and may be composed of a molecularly orientable synthetic resin, e.g. a nylontype polyamide, whose coupling heads are molded onto the coupling element. in my concurrently filed. commonly assigned copending appli,cations Ser. No. 624,647 entitled "Slide Fastener," and in the concurrently filed copending application Ser. No. 619,768 entitled "Slide Fastener With Woven Support Tape," there are described and claimed supply-fastener assemblies based upon principles equally significant here. Thus, in the application Ser. No. 624,647, the tape is provided adjacent its marginal edge with a row of openings through which the heads of a slide-fasteneir coupling element project generally transversely to the plane of the fabric, while alongside the coupling element, the tape is formed with a bead, generally a filler cord woven into or stitched to the fabric, the body being drawn against the coupling element throughout its length by the shrinkage of the transverse threads of the tape. The coupling elements themselves are provided with stop formations or configurations against which the body is seated. In copending application Ser. No. 619,768, the support tape is formed along its connecting edge with a woven or knitted fabric tubular portion having lateral openings extending along this ed,-e; the coupling element is inserted in this tube and has its coupling head projecting laterally from the tape through these openings and substantially in the plane of the body of the tube. Upon shrinkage of the fabric tape, the coupling element is anchored in ,place. Above and other objects, features and advantages of the present invention will become more readily apparent 37487)510 4 from the followin.- description, reference being made to the accompanying drawing, in which: FIG. I is a plan view of a portion of a support tape, according to this invention, drawn to an enlarged scale; 5 FIG. 2 is a view of the same tape iuustrating its dimensions and configurations after a shrinkage operation in the flat stage, it being understood that only shrinkage is effected to lock the coupling elements in place; FIG. 3 is a plan view of a portion of a slide-fastener 10 assembly with the slide-fastener heads thereof constituted in accordance with the present invention and matingly interconnected; FIG. 4 is an enlarged, detailed cross-sectional view view taken along the line IV-IV of FIG. 3; 15 FIG. 5 is a cross-sectional view corresponding generally to FIG. 4 but illustrating another slide-fastener arrangement; FIG. 6 is a plan view of the device of FIG. 5; FIG. 7 is a view of the support tape used in the system 20 of FIG. 5 prior to mounting of the couplin- element thereof. FIG. 8 is a view similar to FIG. 7 of still another embodiment of this invention; and FIGS. 9 and 10 are still other views similar to FIG. 8 2,5 of support bands according to this invention. Referring to FIGS. 3 and 4, which show a fragment of a slide-fastener assembly according to this invention, the slide fastener S comprises basically a pair of slidefastener halves H having, along confronting edges E, of 30 a support tape T of each half, a respective coupling element generally designated C and formed with coupling heads interengageably with he coupling heads of the element C extending along the other coupling head. The tapes T may be stitched or otherwise secured to fabrics 35 along the opposite sides of an opening when the slide fastener is to be employed as a separable closure for this opening. Usually, the tape T is applied to the respective fabric layer by stitching along its web W remote from the edge 4'0 E and the coupling element C carried thereby. The coupling elements themselves can be coiled from a monofilament thread of a polyamide or like heat-settable thermoplastic resin or from an extruded strand of molecularly nonoriented resin having a tendency to shrink with 13 time. As will now be more readily apparent from FIGS. 1-4, each slide-fastener tape-half is formed from a band I of woven threads whose weft thread la is shown to extend transversely of the band while the warp threads 50 lb are of a somewhat smaller thickness. The band I is woven, rather than cut, from a woven sheet so that the longitudinal extremities Ic and Id of the band are formed with the looped portions le of the weft threads la. According to this invention, the band I is provided 55 with a row, extending in the Ion.-itudinal direction of the slider and parallel to the coupling elements C, of throughgoing openings 2 with a spacing defined essentially by the thicknesses or gauge t of the weft threads la separating the openings 2. The spacing s between the (;o weft threads la is so designed as to permit the heads 3 of a continuous coupling element to be inserted through the openings 2; altemately, the length I of these openings is such that the thread portions If defining them can be deflected upon introduction of the heads. 65 As can be seen from FIG. 4, each of the coupling elements 4 is generally helicoidally wound from a synthetic resin wire 5 with akeyhole-shaped or pearshaped crosssection so as to form a loop 4 defining each head 3. The latter may be shaped by pressing the loops 4 in a 7o warm state of the synthetic-resin wire in the direction of arrow A (FIG. 3), as described, -for example, in the commonly assigned copending applications Ser. Nos. 591,753 and 473,002 now U.S. Patent No. 3,353,233 of Nov. 21, 1967) filed Nov. 2, 1966 and July 19, 1965. 75 The coupling elements C themselves may be produced
[3]5 by the method set forth in the aforementioned patent and U.S. Patent Nos. 3,243,489 and 3,267,514. Within the coil forming each coupling element and preferably at the respective shank portions 4a, I provide a resilient band 4b constituting a filler about whose inner edge 4c the thread portions If of the respective tapes can be bent. Each tape is formed with a marginal portion M of a width d substantially equal to the width of the band 4b and the shank 4a of the respective coupling element C so that substantially the entire shank portion of the coupling elements can be covered over by the marginal portion M when the latter is folded into a U-shaped configuration (FIG. 4) to retain the coupling element. Advantageously, the projectin.- loop 4 extends beyond the respective edge E of the tape heads T to an extent less than the width d. The shanks 4a associated with each head 3 and loop 4 are parallel and lie in a common plane perpendicular to the longitudinal direction and the tape so that the heads can be closely spaced to admit of a fine seam upon closure of the fastener. The woven bands I (FIG. 1) which are used to form the tapes T of the slide-fastener halves are shrinkable by conventional fabric-treatment techniques at least 10 to 15% in the transverse direction, i.e. perpendicular to the coupling elements C and along the weft threads la, and preferably to the same or a slightly lesser extent in the longitudinal direction (arrow b) along the warp threads la. In the embodiment shown, the shrinkage of the web is represented at I' in FIG. 2 which diagrammatically indicates that, while the thicknesses of the threads remain substantially unchanged, the shrinkage step condenses the fabric in both its length and width throu-h the 10 to 15% mentioned above. The band 1 is not, however, shrunk in its flattened state but is, rather, folded about the couplin-, element C (FIG. 3) upon insertion of the loops 4 through the openings 2 of every thread If thereby permitting the threads to hug the shanks 4a on each tum of the couplin.- element as represented by the threads Ig of FIG. 3. Thus, shrinkage of the tapes T after insertion of the respective heads will draw the weft threads la tightly around the coupling elements and conform the retaining means formed by these threads to the configurations and contours of the portions of the coupling element thereby hugged tightly. Behind the loops 4, the coupling elements C are provided with shoulders 6 sloping from the loops 4 to the shank portions 4a to form a grippable throat 6a about which the threads Ig are ti,@htened by the shrinking step. As can be s-.en from FIG. 3, the spacing D between the loops 4 and the respective heads 3 of the coupling elements C is defined by the threads If interposed between these heads and loops. In this system, three threads If are located between each pair of loops 4 such that D=3t. It will be understood that, when smaller couplingelement spacin,@s are required, lesser numbers of threads If are positioned b-@tween the heads, the threads between the openings 2 in all cases completely bridging the gaps between these heads. Thus, a lesser number of threads can be positioned between the heads to attain the spacing D when the thickness of these threads are correspondingly enlarged. It has been found that these threads form positive spacers for the heads which are especially significant when the coupling elements are of an extruded nonoriented resin and tend to shrink with time. The threads effectively resist narrowing of the interhead gaps. The transverse shrinkage of the weft threads la or some of them ensures the fittingtype attachment of the couplin- elements wh--reas the lon@itudinal shrinkage of the thread, which is proportionally less, determines the spread of the heads. Furthermore, it is possible to form the openings 2, through which the heads are inserted, by stamping the openings from a fabric. In FIG. 9 I show such an arran,@ement. In FIG. 9, the fabric 201 is of a woven character and 3)487)510 6 has both weft threads 201a of relatively high shrinkability and warp threads 201b of somewhat lower shrinkability stamped or punched through at 202 to form openings adapted to receive the heads of the coupling elements as described in connection with FIGS. 1-4. In this case, the weft threads 201f disposed between the openings 202 drape around the throats of the coupling heads and lug the later upon shrinkage of the tape to retain the heads in place and space them apart to the desired degree. The 10 bands 1, 201 may be composed of shrinkable natural fibers, preferably cotton, which are subjected to treatment with water or a moist atmosphere in order to effect the shrinkage step. However, it is also possible to use cotton warp threads lb, 201b and heat-shrinkable weft threads 15 la, 201a to ensure the diverse shrinkage characteristics, the thermoplastic threads being of nylon or polyester such that a heat treatment at temperatures of 180' to 2001 C. in steam or hot air for periods of 20 seconds to 2 minutes are effective to shrink the fibers. Cotton fabrics 20 may also be shrunk according to this invention by conventional preshrinking technique used in the fabric industry, e.g. a chemical treatment with sodium hydroxide or other alkaline solutions. As noted earlier, best results are obtained when the coupling elements C are 25 retained in tube-like formations along the confronting edge E of the tape halves H, such formations being constituted by the U-bent marginal portions M (FIGS. 3 and 4). Tbus the marginal portions are turned back at the openings 2. When the fibers are composed of a syn30 thetic resin, the shrinkage step can be effected concurrently with a bond of the marginal portion to the shanks 4a of the coupling elements C and with a bonding of these shanks to the body portion of webs W of the tapes. FIG. 10 shows yet another modification in which the 35 openings 302 are formed between loops 301f of a knit fabric by omission of courses in a knitting operation. In this case, a marginal portion is formed by further knit courses or wales at M', it being understood that loose loops may likewise be used to form the openings through 40 which the heads of the coupling elements C are inserted. As in the system of FIGS. 1-4, the embodiments illustrated in FIGS. 9 and 10 can have the threads If, 201f and 301f flattened at Ih to form projections which engage behind the necks 6 of the heads 4 and which also define the longitudinal boundaries of the row of 45 openings 2 by forming stops for the adjoining warp threads. In the systems of FIGS. 5-7, 1 show a modified arrangement wherein the fabric 101 (FIG. 7) is formed with the op.-nings 102 between weft threads 101f during 50 the weaving operation by omission of warp threads 101b in the region of the openings. In this system, the marginal portion M" is shown to be formed on the left hand side of the row of openings while the web portion W" is located on the righthand side thereof, the band 55 being used to form the right-hand slide-fastener half of the assembly of FIG. 5. As illustrated in the latter figure, the marginal portion M" of each band is turned about and overlies the shank portion 104a of pear-shaped section whose loops 104 are formed with interlocking heads 60 103 and extend inwardly of the respective edge E" of the slide-fastener halves H". In this embodiment, moreover, the tapes T" are formed originally with an opening width s" (represented in dot-dash lines in FIG. 7) greater than that necessary to cause the warp threads 101f to 65 hub the loops 104 of the couplin@- elements C". Prior to insertion of the coupling elements through the openings 102, the fabric is shrunk to its condition as indicated in dot-dash lines in FIG. 7 (e.g. through approximately 10% in linear dimension) and preferably as here shown by 70 principally a transverse shrinkage. When the weft threads 101a are composed of a thermoplastic material (e.g. nylon monofilament) and the fabric is shrunk by thermal treatment under the conditions stated earlier, the thermal shrinkage renders the fabric elastic in the vicinity of the 75 openings 102 so that the threads IOIG elastically hug
[4]354871510 7 the loops 104 of the coupling elements when the latter are inserted through the relatively constructed openings. The coupling elements themselves can be formed with the formations, slots or other retaining means against which the weft threads can bear to secure the coupling elements. 5 In the embodiments illustrated. generally helicoidal coupling elements are employed, these coupling elements being deformed to have looped heads 103, 104 and relatively parallel shanks 104a. The core 104b may also be 10 a packing of textile material which is so positioned that tlae tapes are shrunk against this core as well. In the embodiment of FIG. 8, the fabric 401 is shown to have relatively thick monofila-mentary weft threads 401a provided with the flattened formation 401h which 15 retain the warp threads 401a bonding the openings 402. The warp threads 401a can be cotton threads, the fabric here being subjected to shrinkage at elevated temperatures and in contact with shrinking solutions. Concurrently with the shrinkage treatment of systems using weft 20 threads or by a thread treattnent of the assembly at the softening temperature of the thermoplastic threads, the threads are bonded, according to this invention, to the coupling elements C, C", etc. The invention described and iflustrated is believed tO 25 admit of many modifications within the ability of persons skilled in the art, all such modifications being considered within the spirit and scope of the invention. I
