US20190021453A1

US20190021453A1 - Slide fastener tape with molded zipper teeth and methods of making same

Info

Publication number: US20190021453A1
Application number: US16/140,117
Authority: US
Inventors: Gary Davis
Original assignee: Ideal Fastener Corp
Current assignee: Ideal Fastener Corp
Priority date: 2016-03-20
Filing date: 2018-09-24
Publication date: 2019-01-24
Also published as: WO2017165260A1; US20170265605A1

Abstract

A molded-teeth slide fastener tape for use in a slide fastener assembly includes a woven portion and a plurality of resin-based teeth. The woven portion includes a cord arranged along an edge thereof and a plurality of spaced-apart perforations, disposed adjacent to the cord, which pass completely through the woven portion. Each of the plurality of resin-based teeth is integrally molded to the woven portion along the cord. Each molded tooth encompasses at least a portion of at least one of the spaced-apart perforations so that each molded tooth extends through the at least one of the spaced-apart perforations and fully around a cross-sectional shape of the cord.

Description

CROSS-REFERENCE TO RELATED APPLICATION

The present application is a U.S. continuation patent application of, and claims priority under 35 U.S.C. § 120 to, U.S. nonprovisional patent application Ser. No. 15/463,016, filed Mar. 20, 2017, which '016 application published as U.S. Patent Application Publication No. US 2017/0265605 A1 on Sep. 21, 2017, which '016 application and its publication are each incorporated by reference herein in their entirety, and which '016 application is a U.S. nonprovisional patent application of, and claims priority under 35 U.S.C. § 119(e) to, U.S. provisional patent application Ser. No. 62/310,754, filed Mar. 20, 2016, and entitled, “SLIDE FASTENER,” which provisional patent application is incorporated by reference herein in its entirety.

COPYRIGHT STATEMENT

All of the material in this patent document is subject to copyright protection under the copyright laws of the United States and other countries. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in official governmental records but, otherwise, all other copyright rights whatsoever are reserved.

BACKGROUND OF THE PRESENT INVENTION

Field of the Present Invention

The present invention relates generally to slide fastener tapes, and, in particular, to a strong and durable slide fastener tape, utilizing molded zipper teeth, that exhibits enhanced resistance to lateral pulling forces.

Background

Slide fasteners (i.e., zippers) generally fall within one of three categories: metal teeth zippers; coil-type zippers; and molded-teeth zippers. Each category of zippers exhibits different physical and aesthetic aspects that make one zipper type preferable over others for certain applications.
Metal teeth zippers were among the first commercially successful zippers. The teeth of such zippers are formed by crimping specially-shaped pieces of metal wire around the beaded edge (i.e., the cord) of fabric slide fastener tapes. Metal teeth zippers have the general appearance of a strong, durable zipper (due at least in part to the use of metal teeth). However, in many cases, metal teeth are easily damaged or inadvertently removed from the slide fastener tape, thereby rendering the zipper unusable. Furthermore, metal zipper teeth are prone to corrosion, which has a negative impact on the long-term durability and quality of the zipper. As a general proposition, manufacturing costs of metal teeth zipper vary based on the availability and cost of high-quality metal wire.
Coil-type zippers are generally acknowledged as being very strong zippers. The “teeth” of coil-type zippers are formed by twisting (i.e., coiling) polyester filament. The coiled filament is sewn to the cord of the slide fastener tape, and a portion of the coiled filament is flattened to form a “tooth.” By firmly attaching polyester coiled filaments to the cord, coil-type zippers are not only quite strong but are generally impervious to corrosion. Furthermore, coil-type zippers have the advantage of being dyeable to any desired color. However, despite their strength, incurring damage to even a single tooth along the length of the zipper has the potential to render the zipper permanently inoperative.
The teeth of a molded zipper are formed by closing a multi-part mold around the slide fastener tapes and injecting a thermoplastic resin into the mold. Once the resin cools and hardens, the resultant molded teeth are very durable. Resins selected for use in manufacturing molded-teeth zippers usually exhibit high stiffness and low friction. Furthermore, the resin can be expected to display dimensional stability across a wide range of use conditions. However, the zipper itself is only as strong as the mechanism by which the molded teeth are held in place along the cord of the slide fastener tape. If a sufficient lateral pulling force is applied (such as a lateral force that pulls one row of interlocked molded teeth away from the other row of interlocked teeth), molded teeth can be removed from the slide fastener tape, thereby rendering the zipper inoperative. Additionally, under high-temperature conditions, a risk exists that the resin used to form the teeth may soften to the point that teeth become deformed and, ultimately, removed from the slide fastener tape. Molded-teeth zippers are often used in large-scale applications where a larger zipper may be useful. However, due to the large size of the individual teeth in such zippers, a removed molded tooth can represent a choking hazard for young children.
Accordingly, a need exists for a strong and durable slide fastener tape, utilizing molded zipper teeth, that exhibits enhanced resistance to lateral pulling forces. Furthermore, a need exists for a method of assembling a slide fastener tape that facilitates an enhanced bond between the molded tooth and the cord of the slide fastener tape. These and other needs are addressed by one or more aspects of the present invention.

SUMMARY OF THE PRESENT INVENTION

Some exemplary embodiments of the present invention may overcome one or more of the above disadvantages and other disadvantages not described above, but the present invention is not required to overcome any particular disadvantage described above, and some exemplary embodiments of the present invention may not overcome any of the disadvantages described above.
Broadly defined, the present invention according to one aspect includes a molded-teeth slide fastener tape for use in a slide fastener assembly. The slide fastener tape includes a woven portion and a plurality of resin-based teeth. The woven portion includes a cord arranged along an edge thereof and a plurality of spaced-apart perforations, disposed adjacent to the cord, which pass completely through the woven portion. Each of the plurality of resin-based teeth is integrally molded to the woven portion along the cord. Each molded tooth encompasses at least a portion of at least one of the spaced-apart perforations so that each molded tooth extends through the at least one of the spaced-apart perforations and fully around a cross-sectional shape of the cord.
In a feature of this aspect, the spaced-apart perforations may be evenly spaced from one another.
In another feature of this aspect, each of the perforations may have an elongated shape. In another feature of this aspect, each of the perforations may have a generally circular shape.
In another feature of this aspect, each molded tooth may fully encompass one of the plurality of spaced-apart perforations. In another feature of this aspect, each molded tooth may fully encompass only a single respective one of the plurality of spaced-apart perforations. In another feature of this aspect, each molded tooth may fully encompass multiple ones of the plurality of spaced-apart perforations.
Broadly defined, the present invention according to another aspect includes a method of making a molded-teeth slide fastener tape. The method includes: weaving a slide fastener tape including a cord arranged along an edge thereof; forming a plurality of spaced-apart perforations through the woven slide fastener tape adjacent to the cord; and integrally molding a plurality of resin-based teeth to the woven slide fastener tape so that a resin forming each tooth fills at least a portion of at least one of the spaced-apart perforations and, thereby, extends fully around a cross-sectional shape of the cord.
In a feature of this aspect, forming the plurality of spaced-apart perforations may include puncturing the woven slide fastener tape with a hot needle perforator. In another feature of this aspect, forming the plurality of spaced-apart perforations may include punching through the woven slide fastener tape with a mechanical punch.
In another feature of this aspect, forming the plurality of spaced-apart perforations may include, during the weaving step: stopping one or more first consecutive weft yarns short of the cord to establish a gap in the slide fastener tape; passing one or more second consecutive weft yarns, immediately adjacent to the one or more first consecutive weft yarns, fully to the cord to close the gap, the one or more first consecutive weft yarns and the one or more second consecutive weft yarns establishing a weft yarn sequence; and repeating the weft yarn sequence to form a pattern of perforations adjacent to the cord, each perforation corresponding to one of the gaps established by the one or more first consecutive weft yarns of the weft yarn sequence.
In another feature of this aspect, the one or more first consecutive weft yarns of the weft yarn sequence may include four consecutive weft yarns, and the one or more second consecutive weft yarns of the weft yarn sequence may include two consecutive weft yarns.
In other features of this aspect, a length dimension of each of the plurality of spaced-apart perforations may be defined by a quantity of the one or more first consecutive weft yarns of the weft yarn sequence; spacing between each of the plurality of spaced-apart perforations may be defined by a quantity of the one or more second consecutive weft yarns of the weft yarn sequence; and/or a width of each of the plurality of spaced-apart perforations may be defined by a distance by which the one or more first consecutive weft yarns are stopped short of the cord.
In another feature of this aspect, the method may further include precisely positioning the slide fastener tape relative to a molding machine so that a mold for each individual tooth fully encompasses only a single respective one of the plurality of spaced-apart perforations.
In another feature of this aspect, the method may further include further comprising positioning the slide fastener tape relative to a molding machine so that a mold for each individual tooth fully encompasses multiple ones of the plurality of spaced-apart perforations. In another feature of this aspect, the resin may be a thermoplastic resin.
In another feature of this aspect, the spaced-apart perforations may be evenly spaced from one another. In another feature of this aspect, each of the spaced-apart perforations may have an elongated shape. In another feature of this aspect, each of the spaced-apart perforations may have a generally circular shape.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

Further features, embodiments, and advantages of the present invention will become apparent from the following detailed description with reference to the drawings, wherein:

FIG. 1A is a diagrammatic front view of a portion of a conventional molded-teeth slide fastener tape;

FIG. 1B is a close-up diagrammatic front view of the conventional molded-teeth slide fastener tape of FIG. 1A;

FIG. 1C is a sectional diagrammatic view of the conventional molded-teeth slide fastener tape of FIG. 1B, taken along line 1C-1C;

FIG. 2 is a diagrammatic front view of a portion of a slide fastener tape, in accordance with one or more aspects of the present invention, having a series of elongated perforations formed adjacent to the cord;

FIG. 3A is a diagrammatic front view of a portion of a molded-teeth slide fastener tape, in accordance with one or more aspects of the present invention, made using the slide fastener tape of FIG. 2 and showing each tooth fully encompassing a single one of the elongated perforations;

FIG. 3B is a close-up diagrammatic front view of the molded-teeth slide fastener tape of FIG. 3A;

FIG. 3C is a sectional diagrammatic view of the molded-teeth slide fastener tape of FIG. 3B, taken along line 3C-3C;

FIG. 4A is a diagrammatic front view of a portion of another molded-teeth slide fastener tape, in accordance with one or more aspects of the present invention, made using the slide fastener tape of FIG. 2 and showing each tooth encompassing a portion of at least one elongated perforation;

FIG. 4B is a close-up diagrammatic front view of the molded-teeth slide fastener tape of FIG. 4A;

FIG. 4C is a sectional diagrammatic view of the molded-teeth slide fastener tape of FIG. 4B, taken along line 4C-4C;

FIG. 5 is a diagrammatic front view of a portion of another slide fastener tape, in accordance with one or more aspects of the present invention, having a series of small perforations formed adjacent to the cord;

FIG. 6A is a diagrammatic front view of a portion of another molded-teeth slide fastener tape, in accordance with one or more aspects of the present invention, made using the slide fastener tape of FIG. 5 and showing each tooth fully encompassing a plurality of the small perforations;

FIG. 6B is a close-up diagrammatic front view of the molded-teeth slide fastener tape of FIG. 6A;

FIG. 6C is a sectional diagrammatic view of the molded-teeth slide fastener tape of FIG. 6B, taken along line 6C-6C;

FIG. 7 is a flowchart illustrating a method of making a molded-teeth slide fastener tape in accordance with one or more aspects of the present invention; and

FIG. 8 is a close-up diagrammatic front view of another slide fastener tape, similar to that of FIG. 2, illustrating the formation of perforations in the slide fastener tape using a weaving process.

DETAILED DESCRIPTION

As a preliminary matter, it will readily be understood by one having ordinary skill in the relevant art (“Ordinary Artisan”) that the present invention has broad utility and application. Furthermore, any embodiment discussed and identified as being “preferred” is considered to be part of a best mode contemplated for carrying out the present invention. Other embodiments also may be discussed for additional illustrative purposes in providing a full and enabling disclosure of the present invention. As should be understood, any embodiment may incorporate only one or a plurality of the above-disclosed aspects of the invention and may further incorporate only one or a plurality of the above-disclosed features. Moreover, many embodiments, such as adaptations, variations, modifications, and equivalent arrangements, will be implicitly disclosed by the embodiments described herein and fall within the scope of the present invention.
Accordingly, while the present invention is described herein in detail in relation to one or more embodiments, it is to be understood that this disclosure is illustrative and exemplary of the present invention, and is made merely for the purposes of providing a full and enabling disclosure of the present invention. The detailed disclosure herein of one or more embodiments is not intended, nor is to be construed, to limit the scope of patent protection afforded the present invention, which scope is to be defined by the claims and the equivalents thereof. It is not intended that the scope of patent protection afforded the present invention be defined by reading into any claim a limitation found herein that does not explicitly appear in the claim itself.
Thus, for example, any sequence(s) and/or temporal order of steps of various processes or methods that are described herein are illustrative and not restrictive. Accordingly, it should be understood that, although steps of various processes or methods may be shown and described as being in a sequence or temporal order, the steps of any such processes or methods are not limited to being carried out in any particular sequence or order, absent an indication otherwise. Indeed, the steps in such processes or methods generally may be carried out in various different sequences and orders while still falling within the scope of the present invention. Accordingly, it is intended that the scope of patent protection afforded the present invention is to be defined by the appended claims rather than the description set forth herein.
Additionally, it is important to note that each term used herein refers to that which the Ordinary Artisan would understand such term to mean based on the contextual use of such term herein. To the extent that the meaning of a term used herein—as understood by the Ordinary Artisan based on the contextual use of such term—differs in any way from any particular dictionary definition of such term, it is intended that the meaning of the term as understood by the Ordinary Artisan should prevail.
Regarding applicability of 35 U.S.C. § 112, ¶ 6, no claim element is intended to be read in accordance with this statutory provision unless the explicit phrase “means for” or “step for” is actually used in such claim element, whereupon this statutory provision is intended to apply in the interpretation of such claim element.
Furthermore, it is important to note that, as used herein, “a” and “an” each generally denotes “at least one,” but does not exclude a plurality unless the contextual use dictates otherwise. Thus, reference to “a picnic basket having an apple” describes “a picnic basket having at least one apple” as well as “a picnic basket having apples.” In contrast, reference to “a picnic basket having a single apple” describes “a picnic basket having only one apple.”
When used herein to join a list of items, “or” denotes “at least one of the items,” but does not exclude a plurality of items of the list. Thus, reference to “a picnic basket having cheese or crackers” describes “a picnic basket having cheese without crackers,” “a picnic basket having crackers without cheese,” and “a picnic basket having both cheese and crackers.” Finally, when used herein to join a list of items, “and” denotes “all of the items of the list.” Thus, reference to “a picnic basket having cheese and crackers” describes “a picnic basket having cheese, wherein the picnic basket further has crackers,” as well as describes “a picnic basket having crackers, wherein the picnic basket further has cheese.”
Referring now to the drawings, in which like numerals represent like components throughout the several views, one or more preferred embodiments of the present invention are next described. The following description of one or more preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses.
FIG. 1A is a diagrammatic front view of a portion of a conventional molded-teeth slide fastener tape 100. FIGS. 1B and 1C are a close-up diagrammatic front view and a sectional diagrammatic view, respectively, of the conventional molded-teeth slide fastener tape 100 of FIG. 1A. As shown in FIGS. 1A-1C, the conventional molded-teeth slide fastener tape 100 includes a fabric tape 105 having a beaded edge, or cord 104, extending along an inner side thereof (i.e., the side that would face the inner side of an opposing slide fastener tape in an assembled slide fastener). In many cases, the cord 104 is integrally formed as part of the slide fastener tape 105, usually via a weaving process.
As perhaps best seen in the sectional view of FIG. 1C, individual teeth 102 are molded to the slide fastener tape along the cord 104. Each individual tooth 102 is formed, via a molding process, so that each pinches or grips the cord 104 at top and bottom surfaces 107,108 of the slide fastener tape 105. It should be apparent that a sufficient lateral pulling force applied to the teeth 102 or the slide fastener tape 105 can result in deformation of the tape 105 (i.e., stretching can make the tape thinner and, thereby, deform the cord 104). If the cord 104 becomes thinned or deformed, there is an increased likelihood that teeth 102 could inadvertently be removed from the cord, thereby rendering the slide fastener inoperable. Furthermore, a lateral pulling force applied to the teeth 102 carries the risk that one or more of the teeth can, themselves, become deformed (such as by the gripping ends 111,112 of the teeth 102 being pulled apart from one another), thereby facilitating inadvertent removal of a tooth from the tape 105.
FIG. 2 is a diagrammatic front view of a portion of a slide fastener tape 205, in accordance with one or more aspects of the present invention, having a series of elongated perforations 220 formed adjacent to the cord 204. As shown in FIG. 2, the slide fastener tape 205 has a beaded edge, or cord 204, extending along an inner side thereof (i.e., the side that would face the inner side of an opposing slide fastener tape in an assembled slide fastener). It is contemplated that the cord 204 can be integrally formed as part of the slide fastener tape 205, usually via a weaving process.
As further shown in FIG. 2, the slide fastener tape 205 includes a series of spaced-apart perforations 220 that extend along a length of the tape, adjacent to the cord 204. In one contemplated embodiment, the perforations 220 are evenly and uniformly spaced apart from one another. In other embodiments, the perforations 220 can be formed periodically, clustered together in groups, or otherwise, as might be required in a particular end-use slide fastener assembly. It is contemplated that perforations can be formed to have any desired size or shape, as might be preferred for a variety of different slide fastener assemblies. In the embodiment depicted in FIG. 2, the perforations 220 are formed as elongated, slotted openings.
As will be discussed in greater detail below, it is contemplated that perforations 220 can be formed in the slide fastener tape 205 by a variety of different mechanisms, including, but not limited to, using a mechanical punch, using a hot needle perforator or by forming the perforations via the weaving process itself.
FIG. 3A is a diagrammatic front view of a portion of a molded-teeth slide fastener tape 200, in accordance with one or more aspects of the present invention, made using the slide fastener tape 205 of FIG. 2 and showing each tooth 202 fully encompassing a single one of the elongated perforations 220. FIGS. 3B and 3C are a close-up diagrammatic front view and a sectional diagrammatic view, respectively, of the molded-teeth slide fastener tape 200 of FIG. 3A. As shown in FIGS. 3A and 3B, individual teeth 202 are molded to the slide fastener tape 205 along the cord 204 to create one half of an interlocking slide fastener. As perhaps best seen in FIG. 3B, the width of each tooth 202 is slightly larger than the length of one of the evenly and uniformly spaced elongated perforations 220. Individual teeth 202 of the embodiment of FIGS. 3A-3C are molded so that each tooth fully covers and encompasses a respective one of the elongated perforations 220. However, it should be noted that there is no requirement that each tooth fully encompass a single perforation. As will be discussed in greater detail below, it is further contemplated that teeth can be molded to the tape so that each tooth covers and encompasses only a portion of one of the perforations, that each tooth covers and encompasses at least a portion of multiple perforations, that each tooth fully covers and encompasses multiple perforations, or that each tooth fully covers and encompasses at least one perforation and covers and encompasses portions of one or more other perforations.
In accordance with the embodiment of FIGS. 3A-3C, teeth molding is accomplished in such a way that each molded tooth 202 corresponds with and fully encompasses a single respective elongated perforation 220. During the molding process, resin that enters the mold for each tooth 202 passes through and fills the respective elongated perforation 220. Once molding is complete, the resulting teeth 202 are integrally molded to the tape 205, as perhaps best seen in the sectional view of FIG. 3C. Rather than just pinch or grip the cord 204, teeth 202 are formed with the molding resin flowing through the tape 205 so that each tooth extends fully around the cross-sectional shape of the cord 204. In this manner, the molded-teeth slide fastener tape 200 exhibits enhanced strength and durability and, in particular, is better conditioned to withstand a lateral pulling force. Furthermore, because each tooth 202 passes through the slide fastener tape 205 via one of the elongated perforations 220, teeth are more impervious to distortion and are generally incapable of being removed from the tape 205 unless the cord 204 itself is severed.
FIG. 4A is a diagrammatic front view of a portion of another molded-teeth slide fastener tape 300, in accordance with one or more aspects of the present invention, made using the slide fastener tape 205 of FIG. 2 and showing each tooth 302 encompassing a portion of at least one elongated perforation 220. FIGS. 4B and 4C are a close-up diagrammatic front view and a sectional diagrammatic view, respectively, of the molded-teeth slide fastener tape 300 of FIG. 4A. As shown in FIGS. 4A and 4B, individual teeth 302 are molded to the slide fastener tape 205 along the cord 204 to create one half of an interlocking slide fastener. The width of each tooth 302 is slightly larger than the length of one of the evenly and uniformly spaced elongated perforations 220. However, rather than each tooth fully encompassing a respective one of the elongated perforations (as in FIGS. 3A and 3B), each tooth 302 molded to the slide fastener tape 205 of FIGS. 4A and 4B covers and encompasses a portion of at least one elongated perforation 220 or portions of multiple elongated perforations 220.
In accordance with the embodiment of FIGS. 4A-4C, teeth molding is accomplished in such a way that each molded tooth 302 corresponds with and encompasses at least a portion of at least one elongated perforation 220. During the molding process, resin that enters the mold for each tooth 302 passes through and fills any portion of elongated perforations 220 covered by the mold. Once molding is complete, the resulting teeth 302 are integrally molded to the tape 205, as perhaps best seen in the sectional view of FIG. 4C. Rather than just pinch or grip the cord 204, teeth 302 are formed with the molding resin flowing through the tape 205 so that each tooth extends fully around the cross-sectional shape of the cord 204. In this manner, the molded-teeth slide fastener tape 300 exhibits enhanced strength and durability and, in particular, is better conditioned to withstand a lateral pulling force. Furthermore, because each tooth 302 passes through the slide fastener tape 205 via one or more of the elongated perforations 220, teeth are more impervious to distortion and are generally incapable of being removed from the tape 205 unless the cord 204 itself is severed.
FIG. 5 is a diagrammatic front view of a portion of another slide fastener tape 405, in accordance with one or more aspects of the present invention, having a series of small perforations 420 formed adjacent to the cord 404. The slide fastener tape 405 has a beaded edge, or cord 404, extending along an inner side thereof (i.e., the side that would face the inner side of an opposing slide fastener tape in an assembled slide fastener). It is contemplated that the cord 404 can be integrally formed as part of the slide fastener tape 405, usually via a weaving process.
Just as with the embodiments described in connection with FIG. 2, the slide fastener tape 405 of FIG. 5 includes a series of spaced-apart perforations 420 that extend along a length of the tape, adjacent to the cord 404. In one contemplated embodiment, the perforations 420 are evenly and uniformly spaced apart from one another. In other embodiments, the perforations 420 can be formed periodically, clustered together in groups, or otherwise, as might be required in a particular end-use slide fastener assembly. It is contemplated that perforations can be formed to have any desired size or shape, as might be preferred for a variety of different slide fastener assemblies. In the embodiment depicted in FIG. 5, the perforations 420 are formed as small, rounded openings.
FIG. 6A is a diagrammatic front view of a portion of another molded-teeth slide fastener tape 400, in accordance with one or more aspects of the present invention, made using the slide fastener tape 405 of FIG. 5 and showing each tooth 402 fully encompassing a plurality of the small perforations 420. FIGS. 6B and 6C are a close-up diagrammatic front view and a sectional diagrammatic view, respectively, of the molded-teeth slide fastener tape 400 of FIG. 6A. As shown in FIGS. 6A and 6B, individual teeth 402 are molded to the slide fastener tape 405 along the cord 404 to create one half of an interlocking slide fastener. As perhaps best seen in FIG. 6B, each tooth 402 fully covers and encompasses multiple small perforations 420 of the slide fastener tape 405.
In accordance with the embodiment of FIGS. 6A-6C, teeth molding is accomplished in such a way that each molded tooth 402 corresponds with and encompasses multiple small perforations 420. During the molding process, resin that enters the mold for each tooth 402 passes through and fills all small perforations 420 covered by the mold. Once molding is complete, the resulting teeth 402 are integrally molded to the tape 405, as perhaps best seen in the sectional view of FIG. 6C. Rather than just pinch or grip the cord 404, teeth 402 are formed with the molding resin flowing through the tape 405 so that each tooth extends fully around the cross-sectional shape of the cord 404. In this manner, the molded-teeth slide fastener tape 400 exhibits enhanced strength and durability and, in particular, is better conditioned to withstand a lateral pulling force. Furthermore, because each tooth 402 passes through the slide fastener tape 405 via multiple small perforations, teeth are more impervious to distortion and are generally incapable of being removed from the tape 405 unless the cord 404 itself is severed.
FIG. 7 is a flowchart illustrating a method of making a molded-teeth slide fastener tape in accordance with one or more aspects of the present invention. It is contemplated that methods, as described herein, can be used to create slide fastener tapes and finished slide fasteners with molded zipper teeth in accordance with any of the previously-described embodiments of FIGS. 3A-3C, FIGS. 4A-4C and FIGS. 6A-6C.
One contemplated method 500 involves weaving the tape, at step 510, in such a way that the beaded edge is formed at one side thereof. Once the tape is woven, a series of perforations can be formed adjacent the beaded edge, at step 520, by any of a variety of different mechanisms. In one contemplated embodiment, perforations are formed using a mechanical punch to remove part of the woven slide fastener tape, thereby defining an opening that passes completely through the tape. In another contemplated embodiment, perforations are formed by using a hot needle perforator to create punctures in the tape. The hot needle perforator can be particularly useful to create perforations without fraying along the edges of the formed perforation. Though a mechanical punch and hot needle perforator can each be used to create perforations of any desired dimensions, it is contemplated that a hot needle perforator can be used to create relatively small, rounded perforations 420 effectively, as described in connection with FIGS. 6A-6C, while a mechanical punch may be well-suited to create elongated perforations 220,320, as described in connection with FIGS. 3A-3C and FIGS. 4A-4C. Additionally, as described in greater detail below in connection with FIG. 8, it is further contemplated that, instead of using a mechanical punch or hot needle perforator, perforations can be formed in the slide fastener tape via the weaving process itself.
Once perforations have been formed in the slide fastener tape, the tape is ready for the teeth molding process at step 530. A molding machine is used to receive the slide fastener tape along its beaded edge. In one contemplated embodiment, the slide fastener tape is precisely arranged in the molding machine so that each individual molded tooth fully covers and encompasses a respective one of the perforations, such as in the embodiment of FIGS. 3A-3C. However, as described above, there is no requirement that each tooth fully encompass a single perforation. In another contemplated embodiment, the slide fastener tape is arranged in the molding machine (without precise arrangement) to ensure that each individual molded tooth covers and encompasses at least a portion of at least one of the perforations, such as in the embodiment of FIGS. 4A-4C. In still another contemplated embodiment, the slide fastener tape is arranged in the molding machine so that each individual molded tooth fully covers and encompasses multiple perforations. In this latter embodiment, small perforation size, such as in the embodiment of FIGS. 6A-6C, can help enable each molded tooth to fully encompass multiple perforations. Here, again, precise arrangement of the slide fastener tape is not required, as the molded teeth are sufficiently large relative to the pitch of the small perforations to ensure that each tooth fully encompasses multiple perforations.
In each of the above-described embodiments, resin is injected into the mold to form zipper teeth. Although various types of resins can be used, it is contemplated that the resin is preferably a thermoplastic resin. In at least one embodiment, DELRIN® resin, which is manufactured by E. I. du Pont de Nemours and Company, is selected as the resin used for molding the zipper teeth. As the resin fills the mold, resin passes through and fills any perforation or portion thereof that is covered by the mold. Once molding is complete, the resulting teeth are integrally molded to the tape (with each individual molded tooth extending through at least a portion of one of the perforations and, thus, fully around the cross-sectional shape of the cord), thereby yielding a molded-teeth slide fastener tape that exhibits increased strength and durability against a lateral pulling force.
The molded-teeth slide fastener tape can then be processed further, at step 540, as part of assembling a slide fastener. Usually, the molded-teeth slide fastener tape is paired with another such tape in order to assemble a finished slide fastener. In this regard, it is contemplated that various finishing steps can be executed with respect to one or both tapes that include, but are not limited to, adding a pin and box assembly to one end of the pair of tapes, adding one or more top stops to the other end of the pair of tapes, and adding a slider body to one of the row of zipper teeth for bringing the molded teeth from one tape into interlocking arrangement with the molded teeth of the other tape. Furthermore, it is contemplated that the molded-teeth slide fastener tapes can be implemented (such as by sewing or adhesion) to various end-use products, such as clothing, garments, luggage, covers for bedding accessories and the like. The molded-teeth slide fastener tapes can impart such articles with a finished and functional slide fastener that combines corrosion-proof construction and an attractive appearance with the enhanced strength and durability arising from the ability to withstand lateral pulling forces (without rendering the slide fastener inoperative due to loss of or damage to individual molded zipper teeth).
FIG. 8 is a close-up diagrammatic front view of another slide fastener tape 605, similar to that of FIG. 2, illustrating the formation of perforations 620 in the slide fastener tape using a weaving process. In at least some embodiments, perforations 620 of any desired shape or size can be formed in the slide fastener tape 605 as part of the weaving process. Transverse yarns, or weft yarns, typically extend fully across the woven tape 605, including the cord 604 that is integrally formed (usually by the weaving process) along one side thereof. However, in some embodiments, it is contemplated that certain weft yarns can be stopped short of the cord 604 by a small margin rather than pass all the way to and/or over the cord 604. By stopping certain weft yarns short of the cord 604 during the weaving process, a perforation 620 can be formed in the slide fastener tape 605 adjacent the cord 604 at the location where the weft yarns would otherwise pass.
A pattern of perforations 620 can be formed in the slide fastener tape 605 by selecting which particular weft yarns are stopped short of the cord 604 and which particular weft yarns are passed through to the beaded edge of the woven tape 605. As shown in one contemplated embodiment, depicted in FIG. 8, four consecutive weft yarns 630 a,630 b,630 c,630 d are stopped short of the cord 604 during the weaving process, thereby defining a perforation 620 adjacent the cord 604 where the yarns would otherwise pass. The four consecutive weft yarns 630 a,630 b,630 c,630 d that are stopped short of the cord 604 are followed by two consecutive weft yarns 630 e,630 f that pass all the way to and/or over the cord 604. This sequence (i.e., four consecutive yarns stopped short and then two consecutive yarns that pass to the edge) can be repeated in succession to define a pattern of evenly and uniformly spaced elongated perforations 620 along the length of the tape.
The quantity of consecutive yarns 630 a,630 b,630 c,630 d that are stopped short of the cord 604 defines the length dimension of the formed perforation 620, and the quantity of consecutive yarns 630 e,630 f that pass all the way to and/or over the cord 604 defines the spacing between formed perforations 620. As should be clear, length dimensions and spacing of the perforations 620 can thus be varied simply by adjusting the respective quantities of consecutive weft yarns in the sequence. The margin by which the yarns 630 a,630 b,630 c,630 d stop short of the cord 604 defines the width dimension of the formed perforation 620. As such, the width dimension of the perforations 620 can be varied by adjusting the location where weft yarns 630 a,630 b,630 c,630 d are stopped short relative to the cord 604.
It is contemplated that the sequence can be selected to coordinate with the dimensions of the teeth to be molded to the slide fastener tape. In one contemplated embodiment, the sequence is selected so that each perforation has a generally elongated shape, whereby each molded tooth either fully encompasses a respective one of the elongated perforations (as in FIGS. 3A-3C) or encompasses at least a portion of one or more of the elongated perforations (as in FIGS. 4A-4C). In another contemplated embodiment, the sequence is selected so that each perforation is small and rounded (or circular), whereby each molded tooth fully encompasses multiple perforations (as in FIGS. 6A-6C).
Based on the foregoing information, it will be readily understood by those persons skilled in the art that the present invention is susceptible of broad utility and application. Many embodiments and adaptations of the present invention other than those specifically described herein, as well as many variations, modifications, and equivalent arrangements, will be apparent from or reasonably suggested by the present invention and the foregoing descriptions thereof, without departing from the substance or scope of the present invention.
Accordingly, while the present invention has been described herein in detail in relation to one or more preferred embodiments, it is to be understood that this disclosure is only illustrative and exemplary of the present invention and is made merely for the purpose of providing a full and enabling disclosure of the invention. The foregoing disclosure is not intended to be construed to limit the present invention or otherwise exclude any such other embodiments, adaptations, variations, modifications or equivalent arrangements; the present invention being limited only by the claims appended hereto and the equivalents thereof.

Claims

What is claimed is:

1. A molded-teeth slide fastener tape for use in a slide fastener assembly comprising:

a woven portion including a cord arranged along an edge thereof and a plurality of spaced-apart perforations, disposed adjacent to the cord, which pass completely through the woven portion; and

a plurality of resin-based teeth integrally molded to the woven portion along the cord;

wherein each molded tooth encompasses at least a portion of at least one of the spaced-apart perforations so that each molded tooth extends through the at least one of the spaced-apart perforations and fully around a cross-sectional shape of the cord.

2. The molded-teeth slide fastener tape of claim 1, wherein the spaced-apart perforations are evenly spaced from one another.

3. The molded-teeth slide fastener tape of claim 1, wherein each of the perforations has an elongated shape.

4. The molded-teeth slide fastener tape of claim 1, wherein each of the perforations has a generally circular shape.

5. The molded-teeth slide fastener tape of claim 1, wherein each molded tooth fully encompasses one of the plurality of spaced-apart perforations.

6. The molded-teeth slide fastener tape of claim 5, wherein each molded tooth fully encompasses only a single respective one of the plurality of spaced-apart perforations.

7. The molded-teeth slide fastener tape of claim 1, wherein each molded tooth fully encompasses multiple ones of the plurality of spaced-apart perforations.

8. A molded-teeth slide fastener tape for use in a slide fastener assembly comprising:

a woven portion including a cord arranged along an edge thereof and a plurality of perforations, disposed adjacent to the cord and generally evenly spaced from one another, the perforations being configured to pass completely through the woven portion; and

a plurality of resin-based teeth molded to the woven portion along the cord;

wherein each molded tooth encompasses at least a portion of at least one of the perforations so that each molded tooth extends through the at least one of the perforations and fully around a cross-sectional shape of the cord.

9. The molded-teeth slide fastener tape of claim 8, wherein each of the perforations has an elongated shape.

10. The molded-teeth slide fastener tape of claim 8, wherein each of the perforations has a generally circular shape.

11. The molded-teeth slide fastener tape of claim 8, wherein each molded tooth fully encompasses one of the plurality of perforations.

12. The molded-teeth slide fastener tape of claim 11, wherein each molded tooth fully encompasses only a single respective one of the plurality of perforations.

13. The molded-teeth slide fastener tape of claim 8, wherein each molded tooth fully encompasses multiple ones of the plurality of perforations.