Backpack including suspension strap

Abstract

A strap system designed to cushion applied tensile force is disclosed. The strap system includes an expandable member configured to deform under the applied tension force and a restriction member that influences the deformation pattern of the expandable member. For example, the restriction member may limit the amount of stretch experienced by the expandable member. The strap system may be incorporated as shoulder straps into a backpack to reduce pressure to the back and shoulders typically experienced by a wearer.

Description

BACKPACK INCLUDING SUSPENSION STRAPCROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims priority from U.S. Provisional Patent Application No.63 / 698,112, filed September 24, 2024, the entire disclosure of which is incorporated herein by reference.FIELD OF THE INVENTION

[0002] The present invention relates to articles that are subjected to a force or load, such as a backpack.BACKGROUND OF THE INVENTION

[0003] Activity or sport bags such as backpacks are popular for transporting items including books, athletic gear and even portable electronic devices. Given the number of items a person may need to transport, it is desirable to manage (e.g., minimize or disperse) the pressure that is applied to the back and shoulders of the user by the should strap caused by the weight of the bag. Thus, articles that are subject to a force or load and / or carry a load (e.g., a bag, a sack, a carrier for an item, etc.) could benefit by cushioning forces applied by the articles during use.BRIEF SUMMARY OF THE INVENTION

[0004] A shoulder strap or other suspension system includes an expandable member and a restriction member. The expandable member includes a folding textile structure biased toward a normal, contracted position that expands (lengthens) under tension or load. The folding textile structure includes a plurality of individual folds formed of peaks and troughs. The peaks and troughs are configured to separate, widen, and / or flatten under tension. In an embodiment, the expandable member is a woven textile or fabric with a plurality of elastic strands forming the warp and a plurality of inelastic strands (e.g., inelastic yarns) forming both the warp and the weft. To form the expandable member, a loom is utilized to weave the inelastic strands around the elastic strands, wherein the elastic strands and a portion of the inelastic strands are placed under tension and the remaining inelastic strands are utilized to form the weft. Upon formation of the woven structure, the tension is removed, thereby permitting the elastic strands to contract. Uponcontraction, the woven textile collapses to form material folds along opposing first and second sides of the expandable member.

[0005] The restriction member is a less resilient structure (e.g., possessing little to no stretch) that affects the movement of the expandable member, e.g., by limiting its degree of expansion. In example embodiments, the restriction member is a woven textile including the second, less elastic (e g., inelastic) strands, with the strands forming both the warp and weft. A method of forming a restriction member includes weaving inelastic strands to form a low stretch or non-stretch textile structure.

[0006] To form the shoulder strap system, the restriction member is coupled to a side or face of the expandable member such that the restriction member forms one or more loops along the side of the expandable member. The restriction member may be stitched at selected locations along its length, thereby forming the fixed anchor points for the loop.

[0007] In operation, the shoulder strap system begins in its normal position in which the expandable member is retracted / collapsed, and the restriction member loops are oriented out of plane. As tension is applied along the length of the shoulder strap system, the expandable member expands by stretching lengthwise until the loops of the restriction member flatten, becoming generally planar. The restriction member locks out, preventing further expansion of the expandable member.

[0008] The suspension system can be incorporated into a carrying structure such as a sports bag to reduce the peak pressure experienced by a user of the carrying structure. In an example embodiment, the suspension system is incorporated into a shoulder strap of a backpack to reduce the pressure of a tensile force or load applied to the back and / or shoulders of a wearer, particularly when the backpack is loaded with weight and / or a wearer is moving while wearing the backpack. In other example embodiments, a backpack has a main body including a front side and a rear side, a pair of shoulder straps, each shoulder strap extending from a first fixed end at an upper portion of the rear side to a second end located near a lower portion of the rear side, where a portion of each shoulder strap includes the resilient strap as previously described.

[0009] The above and still further features and advantages of the present invention will become apparent upon consideration of the following detailed description of specific embodiments thereof.BRIEF DESCRIPTION OF THE DRAWINGS

[0010] FIG. 1A is a view in perspective of an example embodiment of a suspension system incorporating certain features as described herein, the suspension system shown in its normal position.

[0011] FIG. IB is a side view of the suspension system shown in FIG. 1A.

[0012] FIG. 1C is a side view of the suspension system shown in FIG. IB, shown under tension.

[0013] FIG. ID is an enlarged view of a portion of the suspension system shown in FIG. IB.

[0014] FIG. 2A is a view in perspective of another example embodiment of a suspension system incorporating certain features as described herein, the suspension system shown in its normal position.

[0015] FIG. 2B is a side view of the resilient strap of FIG. 2A.

[0016] FIG. 2C is a top or first sideview in plan of the resilient strap of FIG. 2A.

[0017] FIG. 2D is a bottom or second side view in plan of the resilient strap of FIG. 2A.

[0018] FIG. 3A is a view in perspective of the suspension system of FIG. 2A, shown in an expanded state.

[0019] FIG. 3B is a side view of the suspension system of FIG. 2A, shown in an expanded state.

[0020] FIG. 3 C is an enlarged view of a portion of the suspension system in the expanded state or configuration as depicted in FIG. 3B.

[0021] FIGS. 4A and 4B depict enlarged views (side views in FIG. 4A and perspective views in FIG. 4B) showing a side-by-side comparison of a portion of the suspension system in an unstretched (relaxed) state or configuration and in an expanded (stretched) state or configuration.

[0022] FIG. 5A is a front view of a backpack in accordance with an embodiment of the invention.

[0023] FIG. 5B is a rear view of the backpack of FIG. 5 A.

[0024] FIG. 5C is a rear perspective view of the backpack of FIG. 5 A.

[0025] FIG. 5D is a rear perspective view of an enlarged portion of the backpack of FIG. 5A including portions of the shoulder straps.

[0026] FIG. 5E is a first (left) side view of the backpack of FIG. 5A.

[0027] FIG. 5F is a second (right) side view of the backpack of FIG. 5 A.

[0028] FIG. 6 schematically depicts a front view of a wearer of the backpack of FIG. 6A, in which the straps of the backpack are expandable.

[0029] Like reference numerals have been used to identify like elements throughout this disclosure.DETAILED DESCRIPTION OF THE INVENTION

[0030] In the following detailed description, reference is made to the accompanying figures which form a part hereof wherein like numerals designate like parts throughout, and in which is shown, by way of illustration, embodiments that may be practiced. It is to be understood that other embodiments may be utilized, and structural or logical changes may be made without departing from the scope of the present disclosure. Therefore, the following detailed description is not to be taken in a limiting sense, and the scope of embodiments is defined by the appended claims and their equivalents.

[0031] Aspects of the disclosure are disclosed in the accompanying description. Alternate embodiments of the present disclosure and their equivalents may be devised without parting from the spirit or scope of the present disclosure. It should be noted that any discussion herein regarding “one embodiment”, “an embodiment”, “an exemplary embodiment”, and the like indicate that the embodiment described may include a particular feature, structure, or characteristic, and that such particular feature, structure, or characteristic may not necessarily be included in every embodiment. In addition, references to the foregoing do not necessarily comprise a reference to the same embodiment. Finally, irrespective of whether it is explicitly described, one of ordinary skill in the art would readily appreciate that each of the particular features, structures, or characteristics of the given embodiments may be utilized in connection or combination with those of any other embodiment discussed herein.

[0032] Various operations may be described as multiple discrete actions or operations in turn, in a manner that is most helpful in understanding the claimed subject matter. However, the order of description should not be construed as to imply that these operations are necessarily orderdependent. In particular, these operations may not be performed in the order of presentation. Operations described may be performed in a different order than the described embodiment. Various additional operations may be performed and / or described operations may be omitted in additional embodiments.

[0033] For the purposes of the present disclosure, the phrase “A and / or B” means (A), (B), or (A and B). For the purposes of the present disclosure, the phrase “A, B, and / or C” means (A), (B), (C), (A and B), (A and C), (B and C), or (A, B and C).

[0034] The terms “comprising,” “including,” “having,” and the like, as used with respect to embodiments of the present disclosure, are synonymous.

[0035] Referring to FIGS. 1A - ID, a suspension or shoulder strap system 10 is depicted, the system including an expandable member 100 and a restriction member 105 coupled (e.g., attached) to the expandable member. In the illustrated embodiment, the expandable member 100 is a generally elongated structure (possessing a length greater than its width) defining a longitudinal axis LA and a transverse axis TA oriented generally orthogonal to the longitudinal axis. This expandable member 100 defines a first, exterior side or face 110 and a second, user-facing side or face 120 opposite the first side.

[0036] The expandable member is formed of a textile or fabric including mechanically manipulated strands. By selectively placing elastic and inelastic strands within the textile structure, the expandable member 100 is configured to deform under tension (expand or stretch) and then return to its normal position (recover or collapse) when the tension is removed (i.e., it is biased toward its normal position). The expandable member 100 is biased toward normal through its textile structure, which includes elastic strands configured to stretch and recover, enabling the expansion and contraction of the expandable member (discussed in greater detail below). In this manner, the primary expansion direction occurs along the longitudinal axis LA.

[0037] The expandable member 100 includes one or more folds that are adapted to open and close. In an embodiment, the expandable member is a continuous textile structure including segments or sections 130A, 130B. Each section 130A, 130B includes a peak or ridge 135 (along the first side 110 of the expandable member) and a trough or valley 140 (along the second side 120 of the expandable member) or vice versa. In an embodiment, each section 130A, 130B is generally S- shaped with the peak or ridge 135 being generally convex and the trough or valley 140 beinggenerally concave (FIG. ID). The ridges 135 are configured to pivot (fold / unfold) along an upper hinge or crease 145 A and the troughs 140 are configured to pivot along a lower hinge or crease 145B. Accordingly, each section 130A, I 30B (each peak 135 and trough 140) forms a folding structure, providing the expandable member 100 with an array of transverse folds along its length. This continuous pattern of peaks 135 and troughs 140 controls the behavior of the expandable member 100 as it expands and contracts, enabling the expandable member 100 to dynamically support a load and / or attenuate load forces. By selecting the curvature (e.g., the shape of the curve and / or the amplitude and wavelength of sections 130 A, 130B), the mechanical response of the expandable member 100 can be controlled, including its Poisson's ratio (discussed in greater detail below).

[0038] The expandable member 100 may include any dimensions (size and / or shape) suitable for its described purpose). FIGS. IB and ID show the shoulder strap system 10 in its normal (collapsed or unstretched) position. As illustrated, the peak or ridge 135 possesses a peak height PH and the trough or valley 140 possesses a trough height TH. The distance between adjacent peaks 135 is the peak length pl, while the distance between adjacent troughs 140 is the trough length TL. The heights PH, TH cooperate (e.g., combine) to define the overall height H of the section 130A, 130B. In the normal position, the overall height H of the sections 130A, 130B may be generally uniform. By way of example, the section height h may be from about 5 mm to about 15 mm (e.g., about 10 mm, with PH = about 5 mm and PH = about 5 mm). In further embodiments, the section height H may differ from one section 130A, 130B to another section. For example, the section height H may be selected to provide the expandable member 100 with a graduated or gradient height along its length, with some portions of the expandable member possessing greater height (e.g., about 10 mm) and other portions of the expandable member possessing lower height (e.g., about 5 mm).

[0039] Accordingly, when the expandable member 100 is placed under tension sufficient to overcome the bias, the textile will unfold, during which the peaks 135 and troughs 140 initially separate and then flatten. In operation, the expandable member 100 begins in its normal (folded or collapsed) configuration (having length Ln as shown in FIG. IB), where each section 130A, BOB is closed / collapsed, with the troughs 140 and peaks 135 folded / nested onto each other (e.g., are in direct contact). In this normal position, the heights PH, TH of the peaks 135 and troughs 140 (thus the section height H) are at their maximum values. The peak length PL and trough lengthTL, in contrast, are at their lowest values. As the expandable member 100 stretches, the peaks 135 and troughs 140 separate as the creases 145A, 145B pivot open, thereby increasing the distance between adjacent peaks 135 (i.e., the peak length PL increases) and / or increasing the distance between adjacent troughs 140 (i.e., the trough length TL increases). This unfolding causes the expandable member 100 to increase in length, with the expandable member stretching from its normal position with length Ln (as shown in FIG. IB) to its expanded position with length Le (as shown in FIG. 1C). As unfolding continues, the peaks 135 and troughs 140 will continue to pivot open along creases 145 A, 145B, causing the peaks and valleys to flatten as the peak height PH and / or trough height TH continues to decrease until the structure becomes generally flat, with no discernable peaks 135 or troughs 140 (e.g., peak height and / or trough height is approximately zero). Upon release of the tension, the structure, being biased toward normal, the process reverses and the expandable member 100 returns to its normal, collapsed or folded configuration.

[0040] It is desirable to moderate and / or limit the amount of expansion of the expandable member 100 to prevent excessive rebound, to prevent the expandable member from reaching its elastic limit, and / or from stretching beyond the optimum recovery zone of the expandable member (i.e., the threshold amount of stretch where the recovery property of the expandable member 100 diminishes). Accordingly, the shoulder strap system 10 includes a restriction member 105 configured to limit or otherwise influence the movement (expansion) of the expandable member 100. The restriction member 105 is a generally elongated element (possessing a length greater than its width) possessing little or no elastic or mechanical stretch. In an embodiment, the restriction member 105 is a flexible textile element formed by mechanically manipulating strands into the desired textile structure having little to no stretch. In a specific embodiment, the restriction member 105 is an strip of woven fabric such as flat webbing (discussed in greater detail below).

[0041] The restriction member is coupled (e.g., connected) to a side (e.g., the first side 110) of the expandable member 100 such that the restriction member 105 spans (overlaps extends across, bridges, or covers) the folds (the peaks 135 and / or valleys 140) of the expandable member 100. The restriction member 105 may be continuous, extending uninterrupted along the length of the expandable member 100. In an embodiment, the restriction member 105 includes a plurality of individual elements (or segments) placed at selected locations (including in abutting arrangement) along the length of the expandable member 100. In other embodiments, the textile element is a single, continuous element including an array of loops oriented along the length of the expandablemember (discussed in greater detail below). As shown, the restriction member 105 may be generally aligned with the longitudinal axis LA of the expandable member 100.

[0042] In an embodiment, the restriction member 105 is coupled to the expandable member 100 via anchors 150A, 150B, 150C, 150D, 150E, 150F (also called anchor points). By way of example, an anchor 150A - 150F is a row of stitching oriented along the transverse axis TA of the expandable member 100 (i.e., the anchor 150A - 150F extends across the width of the restriction member 105). The anchors 150A - 150F are disposed at selected locations along the length of the restriction member 105, and may be secured to a peak 135, a trough 140, or any other location along the expandable member 100. The measured distance between an anchor pair including a first anchors 150A - 150F and a second anchor adjacent the first anchor is the anchor distance AD (FIG. ID). The anchor distance may be consistent between each anchor pair (i.e., the anchors 150A - 150F may be equidistantly spaced along the expandable member 100). In further embodiments, the anchor distance may differ from a first anchor pair to a second anchor pair.

[0043] The restriction member 105 may possess any dimensions suitable for its described purpose. In an embodiment, the restriction member 105 possesses a length greater than the normal length Ln of the expandable member 100 (i.e., the length of the expandable member in its normal position). To accommodate this difference in lengths, the restriction member 105 includes one or more buckles or bends that project from the expandable member 100. Each bend forms a loop (e g., an arcuate loop such as a semicircle) extending between an anchor pair, namely, i.e., from a first anchor 150A - 150F to a second anchor, the first anchor being adjacent the second anchor. With this configuration, the restriction member 105 extends substantially along the lengthwise dimension of the expandable member 100 in its normal position. The length of the restriction member 105, however, is shorter than the expanded length Le of the expandable member 100, thereby enabling lockout when the expandable member is stretched to the length threshold of the restriction member 105 (discussed in greater detail below). Finally, the width dimension of the restriction member 105 may be less than the width dimension of the expandable member 100.

[0044] In an embodiment, the restriction member 105 may comprise a single, continuous element including an array of loops 155A, 155B, 155C, 155D, 155E aligned along an axis, including the longitudinal axis LA of the expandable member. A loop is a textile element (or fabric section) that is secured to the expandable member 100 by an anchor pair, but the portion of the textile elementdisposed between the anchors is unsecured (e.g., unsecured to the expandable member). Tn its normal position, each loop 155A - 155E may be generally nonplanar (e.g., arcuate), with the unsecured portion extending distally from the expandable member, By way of specific example, the loop is generally arcuate, forming a curve with a predetermined radius of curvature. In the illustrated embodiment, each loop 150A - 150E is generally convex. Beginning proximate a first anchor 150A - 150F, the loop 155A - 155E extends distally from the side 110 of the expandable member 100, curving outward to an apex A. The apex A defines a maximum space or gap between the loop and the expandable member 100, with this distance being the arc height AH. From the apex A, the loop 155A - 155E transitions, curving inward toward the expandable member 100 and terminating proximate a second anchor 150A - 150F (the second anchor being adjacent the first anchor). In this manner, the unsecured portion spans a plurality of folds (the peaks 135 and valleys 140) of the expandable member 100.

[0045] The measured distance along a loop 155A - 155E from anchor 150A - 150F to anchor (e g., from second anchor 150B to third anchor 150C, third anchor to a fourth anchor, etc.) defines the arc length AL of the loop 155A - 155E (also called loop length). This arc length AL is greater than the anchor distance AD measured between the same anchors (e.g., from second anchor 150B to third anchor 150C, third anchor to a fourth anchor, etc.). By way of example, the arc length AL may be about 5% greater than the anchor distance AD, including about 10% to about 30% greater than the anchor distance AD. In a specific embodiment, the arc length AL may be about 15% greater than the anchor distance AD to form the desired arc height AH and, as such, the desired amount of loop movement. In an embodiment, the arch height AH is from about 10 mm to about 20 mm (e.g., about 15 mm).

[0046] The restriction member 105 (thus the loops 155 A - 155E) may be formed of flexible, nonstretch material (e.g., a material such as a textile or film possess less than 5% stretch, including no elastic stretch). In further embodiments, the restriction member 105 is formed of material possessing slight stretch (e.g., possessing 5% - 15% stretch). When possessing stretch, the material forming the restriction member 105 possesses a higher modulus of elasticity (e.g., greater recovery) than the expandable member 100.

[0047] With this configuration, each anchored loop 155A - 155E permits the expansion of the expandable member 100 in the area under each loop. When the expandable member is in its normalposition, the anchored loops 155A - 155E are in their normal, semicircular or curved position, being fully extended such that the arc height AH is at its maximum value. As the length of the expandable member 100 increases, the loops 155A - 155E will flatten, moving from its normal, curved position (FIG. IB) to a flattened position (FIG. 1C). That is, adjacent anchors 150A - 150F move away from each other, lowering the arc height AH of the loop 155A - 155E. This continues until the loop 155 A - 155E reaches a flattened position, becoming generally planar. In this position, the loop 155A - 155E may contact the side 110 (i.e., the peaks 135) of the expandable member 100, becoming generally parallel therewith (as shown, e.g., in FIG. 1C). Sated another way, the arch height AH value of the loop 155A - 155E becomes approximately 0. The anchors 150A - 150F, combined with the non-stretch nature of the material forming the loops 155A - 155E, fix the position of the loops (and thus the restriction member 105) preventing any further extension beyond this flattened position. This, in turn, locks out the expandable member 100, preventing further expansion of the expandable member within the loop area (FIG. 1C). In embodiments where the restriction member 105 possesses slight stretch, the expansion of the expandable member 100 will continue, until the elastic limit of the material forming the restriction member is reached.

[0048] The amount of expansion permitted by the restriction member 105 may be any suitable for its described purpose. The amount of expansion may be established by selecting the preferred anchor distance AD for each loop, the preferred arc length AL for each loop, and / or the preferred number of anchored loops 155 A - 155E forming the restriction member 105. In an embodiment, each anchored loop 155A - 155E may provide localized expansion of the expandable member 100 of about 5% or more, including about 10% to about 35% (e.g., 14% - 18%) from its normal position. By way of further example, a shoulder strap system 10 may be configured with an overall expansion of about 10% or more before lockout, including an expansion of about 15 - 30% from normal (e.g., the expansion length Le of the suspension strap 10 may be at least about 20% greater than normal length Ln).

[0049] With this configuration, the restriction member 105, permits limited expansion or stretch of the expandable member 100, being configured to lock out before the section height H (i.e., the peak height PH and the trough height TH) decreases by a predetermined value. By way of example, restriction member 105 may lock out before the section height H decreases by more than 1% (e.g., from about 2% to about 99%, by about 5% or more, and / or from about 5% to about 50%).In this manner, the expansion of the expandable member 100 can be controlled, with the restriction member 105 locking out before the expandable member 100 stretches beyond its optimum recovery zone or stretches beyond other undesirable stretch lengths.

[0050] In a further embodiment shown in FIGS. 2A - 2C, 3A - 3C and 4A - 4B, a suspension or strap system 20 includes an expandable member 200 with a plurality of angled peaks extending distally from each side of the member. Specifically, the textile construction is configured such that the expandable member defines peaks 220 and valleys 240 oriented transverse the lengthwise dimension of the expandable member 20, where each of the opposing surfaces or sides 260, 280 of the expandable member 200 includes material peaks and / or valleys associated with their respective folds or pleats. The peaks 220 and valleys 240 are oriented consecutively (e.g., peak / valley / peak / valley, etc.) along the length dimension of the expandable member 200. As can best be seen, e.g., in FIGS. 3 A - 3C (when the strap is elongated under tension), the material peaks 220 on side 260 are aligned or correspond with material valleys 240 along the opposing side 280 (i.e., a peak 220 on side 260 corresponds directly with a valley 240 on opposing side 280) and the same vice versa. The peaks 220 are angled, being offset from vertical (e.g., being oriented at a 45- degree angle). The textile construction is dynamic such that when the extendable member 200 is elongated, the distance between adjacent peaks 220 (i.e., a pair of peaks separated by a valley 240) increases.

[0051] As with the embodiment of FIGS. 1 A - ID, to limit the stretch distance and / or dampen the amplitude of the expandable member 200, the suspension system 20 further includes a restriction member 105 coupled (e.g., connected) to the expandable member 200. The restriction member 105 is flat, continuous webbing possessing little or no stretch along its length and / or width. In an embodiment, the restriction member 105 possesses a stretch value of less than about 5% (e.g., no greater than 3%, no greater than 1%, or is generally zero). By way of specific example, the restriction member 105 is a woven textile including inelastic strands formed into webbing.

[0052] The restriction member 105 may possess any dimensions suitable for its described purpose. In an embodiment, the restriction member 105 extends substantially along the lengthwise dimension of the expandable member 200 (e.g., substantially the entire length or a portion of the length of the expandable member). The width dimension of the restriction member 105, moreover, may be less than the width dimension of the expandable member 200. The restriction member 105is coupled with the expandable member 105 such that the restriction member is oriented along the central lengthwise axis of the expandable member 200.

[0053] The restriction member 105 may be positioned on a side of the expandable member 100, 200 (e.g., the first side 260 of the expandable member) and is coupled (e.g., connected) to the expandable member at anchor points (similar to that described in the embodiment of FIGS. 1A - ID) utilizing, e.g., stitching. The stitching is disposed at selected locations along the length of the restriction member 105. The restriction member 105 includes one or more loop sections 320 that extend away from the side 260 of the expandable member 200 to define a space or gap therebetween, and further where the curved or looping portion of each loop section 320 is free or not connected with the expandable member side 260 but includes opposing lengthwise ends 340 that are secured or tacked down to the expandable member side 260 (e.g., via stitching, weld bonding and / or any other securing process). The tacked down (stitched) ends 340 of the loop sections 320 have a length that extends transverse the length of the restriction member 105 and the expandable member 200. When the expandable member is in its normal (unstretched) configuration, a semicircular arc is defined by the curved looping portion between the ends 340 of each loop section 320 and that extends lengthwise in the same lengthwise dimension of the restriction member 105 and expandable member 200.

[0054] As described herein, and similar to the embodiment of FIGS. 1A - ID, the restriction member 105 for the system 20 limits the stretching or elongation of the expandable member 200 along its lengthwise dimension. That is, as the expandable member 200 stretches when placed under tension, the loop sections 320 of the restriction member 105 flatten out, providing a “lock out” feature that limits or prevents further stretching of the expandable member (as shown in FIGS. 3A - 3C, as well as in FIGS. 4A and 4B). The depiction in FIGS. 4A and 4B also show views of a portion of the suspension system 20 in an unstretched or relaxed state or configuration vs. a stretched state or configuration (e.g., at a “lock out” or furthest allowable stretch of the strap due to the maximum elongation of the stretch limiter). As further described herein, the textile webbing of the restriction member 105, including loop sections 320, has an overall length that is greater than the length of the expandable member 200 in its relaxed or unstretched configuration. This allows the loop sections 320 to flatten when the expandable member 200 is elongated or stretched based upon an axial load applied to the expandable member in the direction of its length dimension.

[0055] In an embodiment, the expandable member 100, 200 and the restriction member 105 are textile structures, each formed by mechanically manipulating one or more strands. The term strand includes a single fiber, filament, or monofilament, as well as an ordered assemblage of textile fibers having a high ratio of length to diameter and normally used as a unit (e.g., slivers, roving, single yarns, plies yams, cords, braids, ropes, etc ). In a preferred embodiment a strand is a yarn (a continuous strand of textile fibers, filaments, or material in a form suitable for knitting, weaving, or otherwise intertwining to form a textile fabric). A yarn may include several fibers twisted together (spun yarn); several filaments laid together without twist (a zero-twist yarn); several filaments combined with a degree of twist; and / or a single filament with or without twist (a monofilament).

[0056] The strands forming the textile can be natural strands (e.g., cotton strands, wool strands, silk strands, etc.) and / or synthetic strands formed of one or more types of polymers, including fibers or filaments having one or more polymer components formed within the fibers or filaments. The strands, moreover, include elastic strands and / or inelastic strands. Elastic strands are strands formed of elastomeric material (e.g., 100% elastic material). An elastic strand, by virtue of its composition alone, can stretch under tension and then recover to its original size once the tension is released. Accordingly, elastic strands are utilized to provide a textile with stretch properties. By way of example, the strand may be formed of rubber, elastane (an elastomeric polyesterpolyurethane copolymer) or an elastoester polymer such as a thermoplastic polyester elastomer (TPEE). TPEE is a type of thermoplastic elastomer (TPE), a block copolymer with both hard polyester and soft poly ether segments.

[0057] In contrast, an inelastic strand is formed of a non-elastomeric material such natural and / or synthetic spun staple yarns, natural and / or synthetic continuous filament yarns, and / or combinations thereof. By way of specific example, natural, non-elastomeric fibers include cellulosic fibers (e.g., cotton, bamboo) and protein fibers (e.g., wool, silk, and soybean). Synthetic non-elastomeric fibers include nylon fibers, polyester fibers, polycaprolactam fibers, poly(hexamethylene adipamide) fibers, acrylic fibers, acetate fibers, rayon fibers, and / or combinations thereof. Accordingly, inelastic strands possess no inherent stretch and / or recovery properties by virtue of composition. Inelastic strands include hard yams.

[0058] In an embodiment, the textile structure of the expandable member 100, 200 includes first yarns and second yarns, where the second yams are less elastic then the first yarns (e.g., possess a lower elastic modulus or possess stretch / elongation that is significantly less than that of the first yarns). For example, the second and further yarns can be inelastic yams, having no inherent stretch and / or recovery properties by virtue of composition, while the first yams are elastic yarns. In an embodiment, the first yarns have an elongation or stretch value that is at least 25% greater than the second yams, or at least 40% greater than the second yarns, or at least 50% greater than the second yarns, or at least 75% greater than the second yams, or at least 80% greater than the second yarns, or at least 90% greater than the second yarns, or at least 100% greater than the second yarns, or even still greater.

[0059] In an embodiment, the elastic strand forming the expandable member 100, 200 is a monofilament formed of elastic material such as rubber and / or elastane. The inelastic strand forming the expandable member 100, 200 is a polyester yam. The restriction member 105, moreover, is formed of an inelastic strand such as a polyester yarn. By way of specific example, the expandable member textile (e.g., a woven textile) includes more than 5% elastic strands or elastic yarns based on a total number of strands or yarns that form the expandable member textile. The expandable member textile (e.g., woven textile) can also be limited to having less than 15% (e.g., less than 10%) elastic strands or elastic yarns based on the total number of strands or yarns forming the expandable member textile, with the remainder being inelastic strands or inelastic yarns. The restriction member textile (e.g., woven textile) can include less than 5% elastic strands or elastic yarns based on a total number of strands or yarns that form the restriction member textile. In an embodiment, the restriction member textile includes only inelastic strands or inelastic yarns (i.e., no elastic strand or elastic yam in the restriction member textile).

[0060] As noted above, the textile construction of the expandable member 100, 200 and the restriction member 105 is formed by mechanically manipulating the strands. In an embodiment, the textile construction is a woven textile structure formed via a suitable weaving process. In general, a weaving process comprises interlacing two or more strands or yams together so that the yarns cross each other at substantially right angles to produce a woven fabric. The warp yarns (ends) run lengthwise (longitudinally) in the fabric, while the weft yarns (filling threads or picks) run from side to side (transversely) in the fabric. A set of lengthwise strands or yams (called thewarp) are interlaced with a set of crossing strands or yarn (called the weft) via a loom, thereby forming the weaving pattern

[0061] Several types of weaving patterns may be utilized to form the textile structure of the elongation member 100, 200 and / or the restriction member 105. In plain weaving, the warp and weft are aligned so they form a simple crisscrossed pattern, each weft yarn crosses warp yams, and where each weft yarn can alternately go over one warp yarn and under the adjacent or successive warp yam. The adjacent warp yam inverts this process, with the warp yam crossing under the weft yarn which is successive to the previous yarn crossed over. Other types of weaves include a basket weave (which includes two or more warp and filling / weft yarns woven side by side to resemble a plaited basket), a satin weave (where the face of the fabric consists almost completely of warp or fdling floats produced in the repeat of the weave), a twill weave (characterized by diagonal lines produced by a series of floats staggered in the warp direction), a double weave (which includes two systems of warp or filling yarns combined such that only one is visible on either side), and a leno weave (which includes warp yarns arranged in pairs, with one warp yam twisted around another warp yam between picks of filling yarn). Further still, weaves can be formed in which a yam (e.g., warp yarn) alternates crossing over or under the other yarns (e.g., weft yams) in any selected number or grouping of yarns. For example, a woven textile can be formed in which a warp yam crosses over some number (e.g., 2, 3, 4, . . . N) of the adjacent or successive weft yarns and then crosses under some number of adjacent or successive weft yarns. Any suitable process can be used to form the woven textile structure.

[0062] In an embodiment, the textile construction of the expandable member 100, 200 is a woven textile construction formed using a Jacquard machine or Jacquard loom that implements a Jacquard weaving process. In this process, first, elastic strands or yarns (e.g., elastic strands or cords) are included in the warp and the second, inelastic (or less elastic) strands or yams are included in both the warp and weft. In other words, during the weaving process, first (elastic) strands are inserted at desired location in the warp direction between the inelastic warp strands and the weft strands such that the first strands are intertwined with second strands. In example embodiments, the weaving process can result in elastic first strands being entangled / intertwined, surrounded and / or wrapped or coiled around second strands in the warp and / or weft directions or even have second strands in the warp and / or weft directions wrapped or coiled around the elastic first strands. Thefirst strands can also be inserted at any desired locations in the warp direction (e.g., first yams inserted between groups of second warp yams, where a group can include N second warp yams).

[0063] An example weaving process for forming the suspension strap system 10, 20 is now described. As previously noted, a Jacquard loom can be used to form the expandable member 100, 200. First (elastic) yams are provided on the loom to be introduced in the warp direction, while second yarns (each having an elasticity or elongation value that is less than the first yarns) are inserted in the warp and weft directions via the loom, where the second yarns in the warp and weft directions form the general or main core woven structure while the first yarns (e.g., elastic strands or cords) are inserted in the warp direction at select location so as to be surrounded by warp and / or weft second yarns. The first yams are stretched (tension applied to the first yams) a certain distance during the weaving process in which second yarns are interlaced, wrapped around or entangled with the stretch first yarns as they are combined together via the loom. A selected number of first yarns are provided along the warp direction to facilitate or impart a suitable stretchability for the expandable member 100, 200 formed from the textile along its lengthwise dimension. Upon combining and interlocking the second yarns forming the woven structure with first yarns inserted at suitable locations and all in the warp direction, the tension applied to the first yarns is released and the lengths of the first yarns decrease to about their original (relaxed) dimensions, snapping back to cause the second yams having less elasticity (or being substantially inelastic) in relation to the first yarns to fold or buckle up on opposing sides of the expandable member 100, 200 so as to form the folds or pleats that define the material peaks and valleys along each side of the expandable member (e.g., peaks 220 and valleys 240 along opposing sides 260, 280 of the expandable member 200).

[0064] With this construction, an expandable member 100, 200 is provided that, when displaced (e.g., stretched) from its normal position, it will recover, with the elastic yarns providing restoring force back to the normal position (typically upon removal of the load causing displacement). In other words, expandable member 100, 200 elongates, beginning in its first, normal (unstretched) configuration, and expanding along its length to a second, stretched or expanded configuration. Elongation is the ability to stretch and increase in length when pulled under tension. Recovery is the ability to “snap back” and return to its original shape and dimensions after the tension is released. Elongation (also called stretch) of the elastic strands and inelastic strands, as well as of the expandable member 100, 200 and / or the restriction member 105, can be measured in units oflength (e.g., millimeters, inches) or calculated as a percentage of the original length (e.g., a yam that stretches 100% expands to twice its original length). In particular, an elongation value (also referred to as a stretch value) refers to an amount of elongation of a yarn or material in a dimension (length or width) that is defined with the formula: [(elongated dimension - original dimension) / (original dimension)] x 100. Recovery (elastic recovery or elasticity) is the ability of a yarn or material under tension to recover to its original size and shape immediately after removal of tension causing deformation. For example, a recovery percentage refers to a percentage of an original dimension to which the yam or material relaxes (i.e., no longer under the load or tension) after being stretched along such dimension (e.g., a recovery percentage of at least 90% of a yarn or material indicates that the dimension of the yam or material in the stretch direction after the load is removed will not differ from the original dimension of the yarn or material before being stretched by more than 10%).

[0065] With the described textile construction, the expandable member 100, 200 is configured with desired elongation and recovery properties. The overall elastic modulus of the expandable member 100, 200 is selected to expand / stretch under tension, but instantly cover to its original shape once the tension is removed. For example, the expandable member 100, 200 may begin expanding once a load of five pounds or more is applied to the member. The restriction member 105, however, limits the amount of expansion to maintain the expandable member 100, 200 within its maximum recovery zone. That is, if an elastic material stretches too far (e.g., beyond its elastic limit), its ability to recover diminishes. The restriction member 105, then, limits the stretch such that the expandable member 100, 200 locks out before it reaches this threshold (e.g., the elastic limit of the expandable member and / or the yarns forming the member).

[0066] In a further embodiment, the textile structure of the expandable member 100, 200 may be configured to resist contraction along its transverse axis when tension is applied along the longitudinal axis. As noted above, the expandable member 100, 200 is configured to deform under load and then return to its normal position (recover) when the load is removed. Conventional constructions possess certain deformation characteristics. Specifically, as tension is applied along a first or longitudinal axis LA (called the tension axis, as shown in FIG.4B), the construction will neck or contract along a second axis that is generally orthogonal to the first axis (called transverse axis TA, as shown in FIG.4B). In other words, as the expandable member 100, 200 is stretched inone direction (e.g., its length), it becomes narrower in a second direction (e.g., its width). This deformation may lead to wearer discomfort caused by uneven pressure, friction, and / or chafing.

[0067] The Poisson effect describes this deformation behavior. Poisson's ratio is the measure of this effect, generally defined as the negative ratio of the transverse strain to the longitudinal strain. Thus, Poisson's ratio describes how much a resilient textile construction changes its shape when stretched, i.e., how much the construction contracts / narrows in one direction (transverse axis) when it is stretched in another direction (tension axis). A higher, more positive Poisson's ratio indicates a construction that contracts more when stretched. A Poisson’s ratio equal to zero indicates a material with no lateral deformation occurring within a predetermined extension range or stretch length. Finally, a negative Poisson's ratio indicates a construction that expands / widens when stretched.

[0068] As noted above, conventional textile constructions contract along the axis that is generally perpendicular to the axis of the applied tension. This is because conventional textile constructions possess a strongly positive Poisson’s ratio. By way of example, conventional constructions possess a Poisson’s ratio of at least 0.30, e.g., 0.50 or more. The challenge with conventional resilient strap constructions is that due to the contraction along its transverse axis, conventional constructions will not adequately conform to complex curvatures such as double curvatures and / or synclastic surfaces. Thus, when placed on body, conventional constructions tend to bunch up in areas of the body with complex curvatures, particularly when the body is in motion. This can lead to discomfort for the wearer caused by uneven distribution of pressure, friction and / or chafing.

[0069] To address this issue, the expandable member 100, 200 may possess a textile structure configured to resist contraction / narrowing along the transverse axis (i.e., the axis generally perpendicular to the axis of tension or load) through a predetermined stretch distance (i.e., a specified length of expansion). That is, the expandable member 100, 200 may possess a textile construction that, when placed under tension, resists or reduces the amount of contraction that takes place in the transverse dimension or axis (perpendicular to the applied load). By way of example, the expandable member 100, 200 may be configured such that no deformation occurs along the transverse dimension or axis, with the expandable member textile maintaining its normal width during expansion (e.g., the expandable member narrows no more than 5% along the transverse axis when stretched up to 25% of its original length). In a further example, theexpandable member 100, 200 may be configured to expand along the transverse dimension or axis, becoming wider along the transverse dimension or axis compared to the width in its normal, unstretched state (e.g., increasing in width from about 3% to about 30% (or about 5% to about 15%) under load).

[0070] To lower the Poisson ratio of the expandable member such that the expandable member resists contraction along its transverse axis when tension is applied along the longitudinal axis, the fold pattern can include one or more reentrant features. A reentrant feature is a specific type of concave shape, defined by an inward-pointing curve that turns back into the body of the object. The convex / concave nature of the valleys 135 and troughs 140 expandable member 100, 200 provides this feature, forming a repetitive pattern of concave curves that face inward. Such a repeating pattern of reentrant shapes is generally recognized as lowering the Poisson’s ratio of a textile. The expandable member, designed with a repeating sinusoidal pattern, can further exhibit a negative Poisson's ratio (the key characteristic of an auxetic material), the resulting function of the geometry of the repeating pattern. In example embodiments, the folds of the expandable member (which define the convex / concave nature of the expandable member) provide a repeating pattern that is effective to generate a negative Poisson’s ratio for the expandable member.

[0071] Whether or not the expandable member 100, 200 resists contraction also depends on the degree to which the textile is stretched. The expandable member may possess the desired Poisson's ratio up to a certain stretch threshold, but when stretched past the threshold, lose the ability to resist contraction and / or exhibit expansion behavior. That is, the Poisson ratio may be sufficiently lowered, even negative, during a set expansion length, but then may begin to increase beyond the set expansion length, turning increasingly positive. Accordingly, it is possible that when the expandable member 100, 200 is stretched past a threshold expansion length (e.g., 20% stretch or 25% stretch), the sections BOA, 130B will no longer resist contraction.

[0072] Accordingly, the restriction member 105 of the suspension system may be configured to maintain the expandable member 100, 200 within stretch window effective to exhibit the desired resistance to contraction and / or auxetic behavior. For example, the expandable member 100 (the textile structure) may possess a lowered Poisson’s ratio, resist transverse contraction, and / or experience transverse expansion up to a threshold stretch / elongation of about 25%. Beyond this 25% threshold, however, Poisson’s ratio may become increasingly positive, ultimately causingtransverse contraction to occur. Accordingly, the loops 155 A - 155E of the restriction member 105 possess dimensions effective to maintain the stretch length of the expandable member 100, 200 within the threshold range. For example, when the threshold stretch value of the expandable member is 25% (as noted above), a loop section 130A, 130B may limit the stretch of its corresponding area of the expandable member under the loop to no more than 25%. Similarly, the restriction member 105 may be configured to limit the overall expansion of the expandable member 100, 200 to no more than 25%. In this manner, the restriction member 105 ensures the expandable member 100, 200 maintains an optimum stretch length that resists transverse contraction, maintains the transverse dimensions at a consistent value (e.g. maintaining its width throughout the stretch window), and / or or even exhibits transverse expansion behavior (widening along the transverse axis TA).

[0073] In use, the suspension strap system 10, 20 can be integrated into an article that carries a load or weight. The system 10, 20 assists in dispersing a weight or load coupled with the article or device during use by providing a force damping spring-like effect that can absorb and / or moderate force and dampen an effect of a load applied to the article or device. In particular, the suspension system 10 can be stretched from its original or relaxed configuration (as shown in FIGS. IB, ID, 2A, 2B, 4A and 4B) to an elongated configuration (as shown in FIGS. 1C, 3A - 3C, 4A and 4D) when an axial or tensile force or load is applied to the strap (e.g., tensile force applied along the lengthwise or longitudinal axis of the expandable member). The stretching features of the expandable member 100, 200 provide a dampening of the axial force, where lockout of the stretching of the expandable member 100, 200 is achieved when the loop sections 155A - 155E, 320 of the restriction member 105 are flattened to limit or prevent further axial elongation of the expandable member.

[0074] In an example embodiment as depicted in FIGS. 5 A - 5F, the suspension system 10, 20 is incorporated or integrated with a backpack 520. In particular, a suspension system 10 is integrated or combined with a shoulder strap for the backpack 500. The backpack 500 can include any conventional and / or other suitable features, including a main pocket defined and accessible within a main body of the backpack and further including any additional one or more pockets that are useful for storing one or more different types of items for a particular application.

[0075] Referring to FIGS. 5 A - 5F, backpack 500 comprises a main body or frame that is formed of one or more suitable materials and includes a front side 505 (FIG. 5A), a rear side 504 (FIG. 5B) that faces a user when the user is wearing the backpack as described herein, a top side 510, a bottom side 512, and two opposing sides that connect with the front and rear sides of the backpack. In particular, the backpack 500 includes a left or first side 506 (FIG. 5E) and a right or second side 508 (FIG. 5F). The front, rear, first, second, top and bottom sides 502, 504, 506, 508, 510, 512 of the backpack 500 combine to form a plurality of cavities, compartments or enclosures of varying sizes within the backpack for storing items (e.g., books, water bottles, shoes or other articles of apparel, electronic devices such as laptops and smart phones, etc.). The sides of the backpack combine to define a generally elongated (e.g., rectangular) shape in which a longer or lengthwise dimension of the backpack extends between the top side 510 and bottom side 512 (and thus a widthwise dimension of the backpack extends between the first side 506 and the second side 508, and a thickness dimension of the backpack extends between the front side 502 and the rear side 504).

[0076] Each of the sides of the backpack 500 can be formed of one or more panels (e.g., each side can be formed comprising a single, separate panel or two or more panels or, alternatively, two or more sides can be formed from one or more of the same panels). In embodiments in which the sides of the backpack are formed with two or more panels, the panels can be connected or secured to each other via any suitable connection (e.g., via a sewn or knitted seam, via lamination or any other suitable connection). Two or more sides of the backpack can include one or more openings that define a pocket, compartment or enclosure between two or more panels of the side and / or between two or more sides. A handle 511 (e g., formed of a fabric panel) comprising a loop attached at each end to the top side 510 of the backpack 500 is also provided to facilitate easy lifting of the backpack when not being worn by the user.

[0077] The panels that form the sides of the backpack can be constructed of any suitably lightweight, flexible, water proof or water repellant and / or tear resistant materials including textiles or fabrics that are formed with any one or more suitable types of polymer materials, where the fabrics can further be formed in any suitable manner (e.g., any combinations of polymer fibers, yarns and / or filaments that form a fabric panel via knitting, weaving, nonwoven formation, etc.). Any suitable polymer materials can be used to form the fabric panels including, without limitation, polyamides (e.g., nylon materials), polyurethanes, polyolefins (e.g., polyethylenes,polypropylenes, etc.), polyesters (e.g., polyethylene terephthalate), polyacrylamides, polylactic acids, polyvinyl alcohol, and any variety of copolymers or combinations thereof. In addition, any one or more panels can be formed at least partially of elastomeric materials to provide a certain degree of elasticity to the fabric panel (e.g., to provide 2-way or 4-way stretch to a portion of the panel), where some non-limiting examples of elastic or stretchable fabric materials suitable for forming the outer fabric layer are fabrics comprising one or more combinations of polyesterpolyurethane copolymers referred to generally as elastane (e.g., Spandex or Lycra materials).

[0078] Each panel forming a side or portion of a side of the backpack can further include one or more layers of material. For example, a panel that defines a portion of one or more sides of the backpack can include two or more layers, including an interior surface layer (i.e., an inward or enclosure facing layer) and an exterior surface layer (i.e., a layer that defines a portion of an exterior side of the backpack). One or more intermediate layers can also be provided within a panel (i.e., between the interior and exterior surface layers) so as to provide certain features for the panel. For example, one or more intermediate layers can comprise a foam material (e.g., polyurethane foam) to enhance the cushioning of the panel along one or more sides of the backpack. One or more interior layers can also include a hard and rigid material (e.g., a hard plastic, metal or other suitable material) to enhance the rigidity of the panel at certain locations of the backpack where it may be desired to provide greater stiffness or enhanced structural support. The backpack can further include any selected number and types of enclosures that facilitate access to and selective opening and closing of (e.g., via zippers, Velcro enclosures, buttons, etc.) pockets or cavities disposed between panels of the backpack.

[0079] The rear side 504 of the backpack 500 includes a pair of shoulder straps 550, with each shoulder strap connecting with and extending from the top side 510 in a slightly arced manner downward along and distanced from the rear side 504 toward the lower or bottom side 512. An upper end or fixed end of each shoulder strap 550 connects at or near a top location of the backpack at the top side 510 and / or a portion of the rear side 504 that is in close proximity with the top side 510. An opposing lower end of each shoulder strap 550 connects at a bottom location of the backpack at or near the bottom side 512 and / or a portion of the rear side 504 and left side 506 or right side 508 that is in close proximity with the bottom side 512. Each shoulder strap 550 comprises a plurality of sections, including a main shoulder strap portion or first section 552 that secures at an upper portion of the backpack rear side, and a second section comprising a bulk strap556, a slip lock member 554 that couples the bulk strap with the first section, and an anchor location 558 that secures the bulk strap 556 to a lower portion of the rear end 504 of the backpack. A cross strap connector 560 can also be provided to selectively couple the two shoulder straps 550 together during use (e.g., to maintain the shoulder straps over the shoulders of the user when the backpack is being worn).

[0080] The first section 552 of each shoulder strap 550 includes the suspension system 10 or suspension system 20 as described herein and depicted in FIGS. 1 - 4. In particular, and as can be seen in FIGS. 5A - 5F, the suspension system 10, 20 is incorporated with and / or forms part of the first section 552 at the fixed end or upper location where the first section 552 connects at or near the top side 510 of the backpack 500. In particular, the suspension system 10, 20 is incorporated as a portion of the first section 552 such that it extends from the fixed location at or near the top side 510 to an intermediate location along the first section 552 that is between the fixed location and the lower portion of the backpack strap.

[0081] A portion of the first section 552 that is below the suspension strap 10, 20 (i.e., the portion that couples with bulk strap 556 via slip lock member 554) can be a textile webbing or any other textile material that is substantially inelastic or has an elasticity that is significantly less than the strap 10.

[0082] When items (e.g., books, laptops, gym shoes and / or gym clothing, etc.) are placed within the backpack and the backpack is worn by a wearer 600 as shown in FIG. 6, the weight of the backpack (especially when the backpack is heavy due to a large number of items such as books being provided within the backpack) is distributed evenly across the wearer’s back and shoulders so as to reduce or minimize the impact and “feel” of the weight by the wearer. The suspension strap 10, 20 further provides a shock absorbing feature in that the expandable member 100, 200 stretches until the arcuate loops 155 or loop sections 320 of the restriction member 105 are flattened and lock-out of the strap occurs (preventing further stretch of the suspension strap 10, 20, e.g., as shown in FIGS. 1C, 3A - 3C and FIG. 6, strap stretches a distance D). In example embodiments, the suspension strap 10, 20 can be constructed so as to permit a stretch from original or relaxed (no tension on strap) length to a fully or lock-out stretch length (i.e., restriction member 105 prevents further stretching or overstretching of expandable member 100, 200), where the amount of stretching of the expandable member and the strap 10, 20 can be limited to no greaterthan about 1 inch (2.54 cm), or no greater than about 2 inches (5.08 cm), or no greater than about 3 inches (7.62 cm), or no greater than about 4 inches (10.16 cm). Depending upon a particular embodiment, the suspension strap 10, 20 can be configured with restriction member 105 and expandable member 100, 200 such that the strap and expandable member are permitted to stretch to even greater dimensions (e.g., greater than 4 inches or 10.16 cm). As previously noted, the restriction member has a greater length than the expandable member such that the ratio of length between restriction member to expandable member is greater than 1, e.g., from 1.3: 1 to 2: 1, or from 1.4: 1 to 1.8:1, or from 1.3: 1 to 1.7: 1.

[0083] Thus, incorporating the suspension system 10, 20 into the shoulder strap of a duffle bag, a shoulder sling, or a backpack provides a number of beneficial features during wearing of the backpack. The stretch features of the shoulder straps due to the incorporation with the suspension system 10 results in a uniform stretch and fit of the shoulder straps over the shoulders for various shoulder shapes and sizes. The suspension system 10, 20 provides force attenuation, permitting the expandable member 100, 200 to resiliently elongate under load and the restriction member 105 preventing the expandable member from reaching its elastic limit or its maximum stretch value. In addition, each shoulder strap with the suspension system 10, 20 facilitates an even distribution of the weight against the wearer’s shoulders and back, providing a lighter bag feel while further maintaining optimal spine alignment when the backpack is worn.

[0084] Testing was performed with a control backpack that included conventional shoulder straps (i.e., shoulder straps that are relatively inelastic / non-stretchable) and a backpack having a similar configuration as the control backpack but instead including the suspension strap 10, 20 as described herein. The backpacks were each weighted with 15 lbs and 30 lbs (67 N and 133 N), and pressure sensors were utilized to measure the pressure applied by the straps to a wearer’ s shoulders and back during both static operation (wearer not moving) and dynamic operation (wearer moving, e.g., walking on treadmill).

[0085] The pressure testing demonstrated that the backpack with the suspension straps 10, 20 resulted in improved metrics compared to that of the control backpack with conventional, inelastic shoulder straps. First, the measured dynamic pressure applied to the wearer’s shoulders during dynamic operation (wearer moving) was reduced relative to the control backpack. Second, the measurements indicated that the suspension system 10, 20 improved the amount of contact orcoverage compared to the control backpack. Improved coverage is believed to provide improved pressure dispersion. Third, selected dynamic peak pressures measured with the suspension system 10, 20 were reduced compared to the control backpack. Finally, the suspension system 10, 20 was effective at moderating dynamic pressure, with dynamic pressure fluctuating more in the control backpack than in the backpack including the suspension system.

[0086] While the invention has been described in detail and with reference to specific embodiments thereof, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof. It should be understood that while multiple embodiments were discussed, the features of one embodiment may be incorporated into another embodiment.

[0087] For example, the first and second strands of the textile structure can have any number of different cross-sectional shapes and dimensions and can further have any suitable denier(s). Some non-limiting examples of cross-sectional shapes (i.e., cross-section is transverse a length dimension of the yarn) include round, hollow, trilobal or multi-lobal, polygonal, eccentric and irregular shaped. In addition, yams including two or more different materials can be formed in any suitable manner with particular cross-section including, without limitation, sheath-core, islands-in-the-sea, bicomponent (e.g., round with each component occupying a half of the crosssection of the yam), trilobal tricomponent (e.g., each lobe of the yam cross-section included a different material), striped, etc.

[0088] With the above-described embodiments, a resilient and elastic expandable member is provided. The resilience and elasticity of the expandable member 100, 200 can provide benefits by deforming resiliency under a load to supplying a cushion against the load. Then, once the load is reduced or removed, the expandable member 100 can recover to its original position, and can continue to provide cushioning, structural reinforcement, and support. Additionally, the loops of the restriction member - both individual loops as well as an array of loops - adjust the degree or amount of stretch experienced by the expandable member.

[0089] While the embodiments described herein depict a restriction member on a single side of the expandable member, in alternative embodiments, a restriction member can be provided on each opposing side of the expandable member.

[0090] Additionally, the resilient strap with restriction member as described herein can be applied to any load or weight bearing strap, leash, handle or other carrying or tethering device in which reduction of the effect of the force or load experienced by a wearer / user is desired. The resilient strap with restriction member can be applied in any manner to device depending upon a particular application. The loop sections of the restriction member can be of the same or varying sizes / lengths (where the length of each loop section is determined as the distance between the two endpoints or tacked down ends of the loop section) and can be spaced at any suitable locations along the stretchable expandable member of the resilient strap. For example, loop sections of the restriction member can be of a first length in one area or section of the resilient strap and can then vary so as to be of a second (e.g., greater) length in another area or section of the resilient strap.

[0091] In an embodiment, the restriction member 105 permits the overall elongation of the strap from a value of approximately 35% to approximately 65% elongation (at 10-pound load) from normal. In other words, the restriction member prevents or limits the expandable member from stretching to its full elongation under a particular load and without shearing to a certain percentage of such full elongation (thus achieving the “lock out” effect for the strap).

[0092] As noted herein, the restriction member 105 (i.e., elongated textile web material with loop sections 320) has a greater length than the resilient expandable member 100, 200 in its relaxed or unstretched configuration. Depending upon certain embodiments (e.g., when the suspension strap 10, 20 is implemented in shoulder straps of a backpack as described herein), the ratio of length of restriction member to length of expandable member (in relaxed / unstretched configuration) is greater than 1, e.g., from 1.3: 1 to 2: 1, or from 1.4: 1 to 1.8: 1, or from 1.3: 1 to 1.7: 1. The restriction member is also preferably formed of yams or other material that renders the restriction member relatively inelastic. Thus, when the restriction member 105 is elongated to its full length, with loop sections 320 flattened (as show in FIGS. 3A - 3C and also the stretched configuration of FIGS. 4A and 4B), further stretching of the expandable member 100, 200 is limited or prevented (i.e., the resilient strap has reached its full elongated length). The length of the restriction member 105 and distance between tacked down or secured ends 340 of the loop sections 320 can be relatively constant (e.g., each loop section 320 can extend the same distance or number of peaks 220 of the expandable member 100, 200). Alternatively, and depending upon a certain embodiment in which the suspension strap 10, 20 is used, the lengths of the loop sections 320 can be varied at different locations along the expandable member 100, 200. As previously noted, loopsections of the restriction member can be of a first length in one area or section of the resilient strap and can then vary so as to be of a second (e.g., greater) length in another area or section of the resilient strap.

[0093] As described herein, a resilient strap with stretch-limiting features can be incorporated for use into a number of items or products that are configured to carry one or more objects by an individual (i.e., human), an animal or any other transport or carrying structure. In a non-limiting example embodiment as described herein, the resilient strap can be incorporated within a shoulder strap of a backpack.

[0094] The resilient strap is formed as a fabric or textile material with elastic first yarns oriented in the same direction, and further with second yarns that are non-elastic or have an elasticity that is less than the elasticity of the first yarns oriented in the same direction as the elastic first yarns and in a transverse (e.g., orthogonal) direction of the first yarns. The textile material of the resilient strap can be formed by any suitable process including, without limitation, weaving, knitting, embroidery, etc. In a preferred embodiment, the textile material is formed from a weaving process in which elastic first yarns are inserted in the warp direction of the woven textile material and are further coupled (e.g., combined or entangled / intertwined) with second yams forming warp and weft yarns of the woven textile material. A yarn used to form the textile material can comprise a single filament, fiber, thread or strand (also referred to as a monofilament), or a plurality of filaments, fibers, threads or strands that are combined in any suitable manner, e.g., twisting (also referred to as a multifilament yarn). The yarns can further be textured or processed in any other suitable manner. In example embodiments, the elastic first yams comprise monofilaments, strands or cords that extend in the warp direction of the woven textile material.

[0095] In addition, the elastic first yarns can be placed under tension by stretching when combined with the second warp and weft yarns during formation of the textile material or structure and, after formation of textile structure in which the elastic first yarns are coupled and / or entangled / intertwined with second warp and / or weft yarns, the tension on the first yarns is then released. This results in the first yarns relaxing and snapping or reverting back to their original (unstretched) lengths, further resulting in the formed textile structure having an undulating or corrugated configuration along opposing lengthwise sides or surfaces of the textile structure. In this configuration, the textile structure can be elongated or stretched along the length of the resilientstrap (i.e., along the warp direction or direction in which the first yarns extend). A restriction member is further coupled with and extends (e.g., in a lengthwise direction) along a surface of the textile structure so as to limit an amount or degree of stretch of the resilient band during use.

[0096] Furthermore, mechanical manipulation of the strands to form the textile structure of the expandable member 100, 200 may be achieved via a knitting process. Knitting is a process for constructing fabric by interlocking a series of loops (bights) of one or more strands organized in wales and courses. In general, knitting includes warp knitting and weft knitting. In warp knitting, a plurality of strands runs lengthwise in the fabric to make all the loops. In weft knitting, one continuous strand runs crosswise in the fabric, making all of the loops in one course. Weft knitting includes fabrics formed on flat knitting machines. With a flat knitting machine, the fabric is produced in flat form, the strands / loops alternating back and forth across the fabric. In embodiments in which the textile material or structure of the elastic strap is formed as a knit material or structure via a flat knitting process, any suitable one or more types of stitches can be used to form the knit structure including, without limitation, a plain stitch, a rib stitch, a purl stitch, a missed or float stitch (to produce a float of yarn on a side of the fabric), and a tuck stitch (to create an open space in the fabric).

[0097] Thus, in accordance with the embodiments described herein, a backpack comprises an enclosure for storing items, and a shoulder strap system coupled to the enclosure. The shoulder strap system comprises an expandable member defining a longitudinal axis and a transverse axis, the expandable member comprising a resilient textile including a plurality of folds generally aligned on the transverse axis, and a restriction member configured to limit expansion of the expandable member, the restriction member comprising a textile element coupled to the expandable member, the textile element extending from a first anchor to a second anchor.

[0098] The textile element of the backpack can be secured to the expandable member by the first anchor and the second anchor, and the textile element can be unsecured in an area between the first anchor and the second anchor.

[0099] The plurality of folds can include a generally concave fold and a generally convex fold. In addition, the expandable member can expand when a tensile force is applied in a longitudinal direction of the expandable member, and the textile element of the restriction member can becapable of transitioning from a generally convex configuration to a generally planar configuration during expansion of the expandable member.

[0100] The restriction member can comprise a plurality of textile elements generally aligned with the longitudinal axis of the expandable member. In addition, the expandable member can resist contraction along the transverse axis as tension is applied along the longitudinal axis.

[0101] The folds of the expandable member can be organized in a repeating pattern effective to lower a Poisson’s ratio of the expandable member. The folds of the expandable member can also be organized in a repeating pattern effective to generate a negative Poisson’s ratio for the expandable member.

[0102] The resilient textile of the expandable member can comprise a woven textile including more than 5% elastic strands based on total number of strands that form the resilient textile, and the textile element of the restriction member can comprise a woven textile including less than 5% elastic strands based on a total number of strands that form the textile element.

[0103] The expandable member can be biased toward a normal, contracted position by elastic strands within the resilient textile of the expandable member, the expandable member can be capable of expanding from the normal, contracted position to a fully expanded position by increasing a distance between adjacent folds, the restriction member can extend longitudinally along the expandable member such that the restriction member spans the plurality of folds, and the restriction member can prevent expansion of the expandable member to the fully expanded position.

[0104] In another embodiment, a shoulder strap system comprises an expandable member defining a longitudinal axis and a transverse axis, the expandable member comprising a resilient textile including a plurality of folds oriented on the transverse axis, and a restriction member configured to limit expansion of the expandable member, the restriction member comprising a textile element coupled to the expandable member, the textile element extending from a first anchor to a second anchor.

[0105] The textile element can be secured to the expandable member by the first anchor and the second anchor, and the textile element can be unsecured in an area between the first anchor and the second anchor.

[0106] The expandable member can comprise a first, generally concave fold and a second, general convex fold. In addition, the expandable member can expands when a tensile force is applied along the longitudinal axis of the expandable member, and, during expansion of the expandable member, the textile element can be capable of transitioning from a generally convex configuration to a generally planar configuration.

[0107] The restriction member can comprise an array of textile elements generally aligned with the longitudinal axis of the expandable member. In addition, the expandable member can resist contraction along the transverse axis as tension is applied along the longitudinal axis.

[0108] The folds can be organized in a repeating pattern effective to lower a Poisson’s ratio of the expandable member. The folds can also be organized in a repeating pattern effective to generate a negative Poisson’s ratio for the expandable member.

[0109] The resilient textile of the expandable member can comprise a woven textile including more than 5% elastic strands based on total number of strands that form the resilient textile, and the textile element of the restriction member can comprise a woven textile including less than 5% elastic strands based on a total number of strands that form the textile element.

[0110] The expandable member can be biased toward a normal, contracted position elastic strands within the resilient textile of the expandable member, the expandable member can be capable of expanding from the normal, contracted position to a fully expanded position by increasing a distance between adjacent folds; the restriction member can extend longitudinally along the expandable member such that the restriction member spans the plurality of folds, and the restriction member can prevent expansion of the expandable member to the fully expanded position.[OHl] It is intended that the present invention covers the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents. It is to be understood that terms such as “top,” “bottom,” “front,” “rear,” “side,” “height,” “length,” “width,” “upper,” “lower,” “interior,” “exterior,” “medial,” “lateral,” and the like as may be used herein, merely describe points of reference and do not limit the present invention to any particular orientation or configuration.

Claims

What is claimed:

1. A backpack comprising: an enclosure for storing items; and a shoulder strap system coupled to the enclosure, the shoulder strap system comprising: an expandable member defining a longitudinal axis and a transverse axis, the expandable member comprising a resilient textile including a plurality of folds generally aligned on the transverse axis; and a restriction member configured to limit expansion of the expandable member, the restriction member comprising a textile element coupled to the expandable member, the textile element extending from a first anchor to a second anchor.

2. The backpack according claim 1, the textile element is secured to the expandable member by the first anchor and the second anchor; and the textile element is unsecured in an area between the first anchor and the second anchor.

3. The backpack according to claim 2, wherein the plurality of folds includes a generally concave fold and a generally convex fold.

4. The backpack according to claim 3, wherein: the expandable member expands when a tensile force is applied in a longitudinal direction; and the textile element of the restriction member is capable of transitioning from a generally convex configuration to a generally planar configuration during expansion of the expandable member.

5. The backpack according to claim 1, wherein the restriction member comprises a plurality of textile elements generally aligned with the longitudinal axis of the expandable member.

6. The backpack of claim 1, wherein the expandable member resists contraction along the transverse axis as tension is applied along the longitudinal axis.

7. The backpack of claim 1, wherein the folds of the expandable member are organized in a repeating pattern effective to lower a Poisson’s ratio of the expandable member.

8. The backpack of claim 1, wherein the folds of the expandable member are organized in a repeating pattern effective to generate a negative Poisson’s ratio for the expandable member.

9. The backpack according to claim 1, wherein: the resilient textile of the expandable member comprises a woven textile including more than 5% elastic strands based on total number of strands that form the resilient textile; and the textile element of the restriction member comprises a woven textile including less than 5% elastic strands based on a total number of strands that form the textile element.

10. The backpack according to claim 1, wherein: the expandable member is biased toward a normal, contracted position by elastic strands within the resilient textile of the expandable member; the expandable member is capable of expanding from the normal, contracted position to a fully expanded position by increasing a distance between adjacent folds; the restriction member extends longitudinally along the expandable member such that the restriction member spans the plurality of folds; and the restriction member prevents expansion of the expandable member to the fully expanded position.11 . A shoulder strap system comprising: an expandable member defining a longitudinal axis and a transverse axis, the expandable member comprising a resilient textile including a plurality of folds oriented on the transverse axis; and a restriction member configured to limit expansion of the expandable member, the restriction member comprising a textile element coupled to the expandable member, the textile element extending from a first anchor to a second anchor.

12. The shoulder strap system according claim 11, the textile element is secured to the expandable member by the first anchor and the second anchor; and the textile element is unsecured in an area between the first anchor and the second anchor.

13. The shoulder strap system according to claim 12, wherein the expandable member comprises a first, generally concave fold and a second, general convex fold.

14. The shoulder strap system according to claim 13, wherein: the expandable member expands when a tensile force is applied along the longitudinal axis of the expandable member; and during expansion of the expandable member, the textile element is capable of transitioning from a generally convex configuration to a generally planar configuration.

15. The shoulder strap system according to claim 11, wherein the restriction member comprises an array of textile elements generally aligned with the longitudinal axis of the expandable member.

16. The shoulder strap system of claim 11, wherein the expandable member resists contraction along the transverse axis as tension is applied along the longitudinal axis.

17. The shoulder strap system of claim 11 , wherein the folds are organized in a repeating pattern effective to lower a Poisson’s ratio of the expandable member.

18. The shoulder strap system of claim 11, wherein the folds are organized in a repeating pattern effective to generate a negative Poisson’s ratio for the expandable member.

19. The shoulder strap system according to claim 11, wherein: the resilient textile of the expandable member comprises a woven textile including more than 5% elastic strands based on total number of strands that form the resilient textile; and the textile element of the restriction member comprises a woven textile including less than 5% elastic strands based on a total number of strands that form the textile element.

20. The shoulder strap system according to claim 11, wherein: the expandable member is biased toward a normal, contracted position elastic strands within the resilient textile of the expandable member; the expandable member is capable of expanding from the normal, contracted position to a fully expanded position by increasing a distance between adjacent folds; the restriction member extends longitudinally along the expandable member such that the restriction member spans the plurality of folds; and the restriction member prevents expansion of the expandable member to the fully expanded position.

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