Patent Application
20110239415
1. Field of the Invention
The present invention is directed to a closure device
2. Description of the Related Art
Zipper closures are widespread, used to join edges of myriad objects, including luggage, clothing, pockets, pouches, etc. Zippers perform interdigitalization of teeth, hooks, or coils that are arranged in opposition and are engaged or disengaged by means of a slider that draws them into contact or forces them apart. One hallmark of zippers is that this engagement or disengagement occurs via lateral movement in the plane of closure. In other words, the engaged teeth, hooks, or coils depend one upon the other laterally, along the entire length of the closure, from a fixed stop to the slider.
This lateral interdependence is a frequent cause of zipper failure. Specifically, in the event that one tooth, hook, or coil is damaged or kinked, the dependency to each of its neighbors is interrupted, causing the closure to fail and allowing the opposing sides to be separated easily.
Engagement and disengagement of zipper elements requires that the means of support be highly flexible. This often is achieved by using a bias-woven textile strip (commonly called “zipper tape”) that is worn out easily by use and that often is permeable to moisture, dust, and dirt. To alleviate this, supplemental sealing elements may be employed, but these may restrict mobility of the zipper tape. As such, zippers with these added elements are hard to open and close and may have limited flexibility.
With the advent of technology for extruding polymers, alternatives to zippers have been proposed, such as closures with continuous outer and inner strips of material. However, due to the continuous nature of these strips, closures of this type cannot engage and disengage readily when the plane of closure follows a curve, such as at a corner of a container. Passage of the slider along the length of the closure creates radial differences between the paths of the strips. In turn, the radial differences create differences in the peripheral distance of the inner and outer strips. As a result, the strips may be compressed together, hindering passage of the slider.
What is needed is a closure device that provides a secure closure with reliability, durability, flexibility, and/or ease of manipulation. For example, the closure may retain its integrity in the event of localized damage and retain its flexibility and ease of use when modified to resist penetration by moisture, dust, and dirt. Additionally, the closure may provide firm engagement and avoid binding at the point of engagement when the plane of closure is curved, such as when the closure turns a corner.
In one aspect, a closure system may comprise a plurality of first keys coupled to a skirt and a plurality of second keys coupled to a second skirt, each of the first and second keys comprising a base, a finger and a flange, a top and an underside; wherein, when coupled, the underside of a first key is proximate the top of an opposing second key, which may be generally in the plane of closure. The system further may include a slider having a first foot configured to translate proximate the top of the first keys, and a second foot configured to translate proximate the underside of the second keys, said feet configured to press the first and second keys together when the slider is moved in one direction and an interior portion configured to separate the first and second keys when the slider is moved in an opposite direction.
Each of the first keys further may comprise a protrusion extending away from the underside, and each of the second keys further may comprise an opening extending inward from the top, preferably completely through the second key. In addition, the flanges of the first keys may comprise a narrow portion extending from a respective base and a wider portion extending from the narrow portion.
In another aspect, a closure system may comprise a plurality of first keys having a base, a finger with a protrusion extending from an underside, and a flange, wherein the base has a thickness larger than a thickness of the finger, and a plurality of second keys having a second base, a second finger with a top having an opening or slot, and a second flange, wherein the second base has a thickness larger than a thickness of the second finger; wherein, when coupled, the underside of a first key is proximate the top of an opposing second key, generally in the plane of closure and wherein, when coupled, the flange and the second flange are generally in the plane of closure. The closure further may include a slider configured to engage and disengage the pluralities of first and second keys, the slider comprising an outer foot proximate the first keys and an inner foot proximate the second keys. The outer foot may include a compressor and a plurality of guides, wherein the guides are configured to receive portions of the base and second base, and the inner foot may include a compressor and a plurality of second guides, wherein the second guides also may be configured to receive second portions of the base and second base.
The slider may include a splitter between the outer and inner feet, the splitter including a plurality of wedge segments separated by a channel extending at least partially through the splitter. The splitter also may include an upper surface and a lower surface, the surfaces intersecting at both a leading edge and a trailing edge, wherein the splitter is configured to separate engaged first and second keys when moved in a first direction, and the slider may include opposing feet to couple disengaged first and second keys when moved in a second direction.
In still another aspect, a closure system may include a plurality of first keys separately coupled to a skirt, a plurality of second keys separately coupled to a second skirt, a slider having an outer foot, an inner foot, and a splitter therebetween, the slider configured to translate along the pluralities of first and second keys, wherein, when coupled, the underside of a first key is proximate the top of an opposing second key, generally in the plane of closure, and further wherein engagement of an opposed first key and second key is generally independent of engagement of a neighboring opposed first key and second key. Each of the first keys may comprise a protrusion extending away from an underside, and each of the second keys may comprise an opening extending inward from a top. In addition, each of the first keys may have a height and may comprise a base and a flange extending rearward from the base, wherein the flange is off-centered along the height. Moreover, each of the second keys may comprise a finger having a top, an underside, a proximal end proximate a base, a distal end spaced from the proximal end, and a plurality of sides extending between the top and the underside, from the proximal end to the distal end, wherein each of the plurality of sides tapers inwardly from the proximal end to the distal end. The closure system also may include a sealing strip configured to contact and/or form a seal with first keys and to cover the first and second keys when the keys are engaged.
These and other features and advantages are evident from the following description of the present invention, with reference to the accompanying drawings.
As seen in
Turning to
Preferably, keys may be displaced by opposite rotation relative to the plane of closure 2, for example, about axes of rotation 4, 6 and/or by vertical movement generally perpendicular to plane of closure 2. Keys may be constructed so that axes 4, 6 may be generally aligned with plane of closure 2, which may allow plane of closure 2 to be deflected freely without creating radial differences between the rows of outer and inner keys.
As seen in
Finger 24 may include a proximal end 26 proximate base 22 and a distal end 28 generally opposite base 22. First side 30 and second side 32 may extend along a length of keys 20, e.g., between proximal end 26 and distal end 28, or between base 22 and distal end 28. First and second sides 30, 32 may be generally planar and, in one embodiment, may be generally parallel to each other. Additionally, first keys 20 each may have a plane of symmetry extending generally perpendicular to plane of closure. First and second sides 30, 32 also may include tapered portions 31, 33, respectively, proximate distal end 28. As discussed below, tapered portions 31, 33 may allow first keys 20 to flex and not interfere with adjacent first keys 20, e.g., when compressing inward.
Top side 34 may be generally planar surface, although other configurations are possible. For example, top side 34 of keys 20 may include a slight radius of curvature to allow smooth passage under the upper foot of the slider 100 (described below), e.g., to avoid the outer keys 20 trapping against the foot due to slight lifting when traveling on a bend. In another embodiment, as seen in
Turning to
As seen in
Second keys 60 may include first sides 70 and second sides 72. As with keys 20, these sides may be generally symmetrical about a central plane of symmetry. Sides 70, 72 may be generally parallel. Preferably, however, sides 70, 72 may taper inward from proximal end 66 toward distal end 68. Moreover, sides 70, 72 may include secondary tapered portions 71, 73 proximate distal end 68 that taper inward more steeply than a remainder of sides 70, 72. Tapering of sides 70, 72 and/or secondary tapered portions 71, 73 may allow second keys 60 to not interfere with adjacent second keys 60, e.g., when disengaging keys around a bend, or when closure 10 is flexed inward.
As opposed to first keys 20, second keys 60 may include one or more openings 78 or other female elements adapted to receive protrusion(s) 38. Opening 78 extends inward from top 74 at least partially, and preferably completely, through second key 60. Opening 78 may include a first sidewall 80 and second sidewall 82 generally opposite opening 78 from first sidewall 80, as seen in
Although one form of engagement is described in greater detail herein, it will be appreciated that opposing keys 20, 60 may engage by any form of pressure-fitted or interference-type closure, such as tongue and groove, ball and socket, or other male-female-type connections.
Returning to
In one embodiment, fingers 24, 64 may be substantially centered along height of keys 20, 60, such that about half of bases 22, 62 are above fingers 24, 64, and about half of bases 22, 62 are below fingers. Flanges 46, 86 may be similarly centered. Preferably, however, flange 46 may be offset closer to underside 36, and flange 86 may be offset closer to top side 74. For example, center of flange 46 may be offset from center of key 20 by an offset distance OD, as seen in
Keys may include ribs 23, 63 for assisting in alignment and engagement of keys 20, 60. In one embodiment, first keys 20 and second keys 60 may be substantially similarly sized and, when engaged, may be substantially aligned along a length of closure 10. In another embodiment, first and second keys may have edges that are offset when engaged so that keys overlap, which may provide better sealing of closure, e.g., against dirt, moisture, etc.
As described above, the geometry of the keys may differ depending on whether they are designed to be inner keys 60 or outer keys 20. Keys 60 located on the inner side of closure 10 may be tapered along their sides 70, 72 and/or at their distal ends 68 to avoid interference with each other when closure 10 is deflected, such as at a suitcase corner, or when the inner keys 60 are rotated inward for disengagement with outer keys 20. Conversely, outer keys 20 may have sides configured so that consecutive keys 20 are generally aligned. Preferably, first side 30 of one outer key may be generally parallel to second side 32 of an adjacent outer key, which may be the case when first side 30 and second side 32 are generally normal to length of closure 10. Alignment of outer keys 20 may allow outer keys 20 to cover gaps formed between tapered sides 70, 72 of inner keys 60, which may aid sealing properties of closure 10.
An impermeable layer of elastic material 200 optionally may be attached by any convenient means to cover the outer row of keys 20. As seen in
Turning now to
Slider 100 may include outer foot 106 and inner foot 122 that combine to guide and press opposed keys together, as seen in
Slider 100 also may include splitter bar 140 joining outer foot 106 and inner foot 122. Splitter bar 140 may join feet directly. Preferably, however, slider 100 may include posts 142, 144 to join splitter bar 140 to inside surfaces of outer foot 106 and inner foot 122, respectively. As seen in
Turning to
Surface planes 160, 162, 164, 166 of splitter bar 140 may twist or be curved from common edges 152, 154, 156, 158 towards the middle of the bar, which may guide rotational deflection of opposing keys 20, 60. In addition, when moving in an engaging direction, this curvature guides keys from common edges 152, 154 toward middle of splitter bar 140, decreasing the clearance between keys 20, 60 and outer foot 106 or inner foot 122 with splitter bar 140. At some point, e.g., when passing end of channel 146, clearance is sufficiently minimized, and keys 20, 60 are brought close enough together by compressor 112 on outer foot 106 and first and second compressors 128, 130 on inner foot 122, such that protrusion 38 on first key 20 engages opening 78 on second key 60, thereby causing engagement of keys. Conversely, when moving in a disengaging direction, common edges 156, 158 may act as wedges between keys 20, 60, opening a gap between them that expands until protrusion 38 no longer engages opening 78, at which point keys 20, 60 are disengaged.
Turning now to
In addition to generally linear arrangements, closure 10 also may operate around curves.
Closure generally, and keys specifically, may be made according to various methods. For example, one method may include molding, trimming, stacking, and feeding keys into a press, for fixing onto a flexible tape. The tape, with keys attached, then may be fed continuously into an extrusion die to be embedded continuously in an extruded flexible skirt. Alternatively, rows of keys may be injection molded, e.g., to predetermined lengths and with thin, frangible supports or films between keys for stabilizing the relative position of keys each beside the next. These rows of keys, still attached to injection sprues, may be transferred to another mold for overmolding a flexible skirt, followed by trimming the completed rows of keys embedded in their skirts. Turning to
Sliders also may be produced according to any convenient methods, including, e.g., die casting or injection molding of parts, followed, to the extent necessary, by assembly using common methods such as snap or press fitting, screwing, riveting, and/or sonic welding.
While the foregoing written description of the invention enables one of ordinary skill to make and use what is considered presently to be the best mode thereof, those of ordinary skill will understand and appreciate the existence of variations, combinations, and equivalents of the specific exemplary embodiments and method herein. The invention should therefore not be limited by the above described embodiments and method, but by all embodiments and methods within the scope and spirit of the invention as claimed.
