US20050258205A1

US20050258205A1 - Shock-absorbing carrying strap

Info

Publication number: US20050258205A1
Application number: US10/851,550
Authority: US
Inventors: John French
Original assignee: Michaels of Oregon Co
Current assignee: MIKE'S HOLDING Co; Michaels of Oregon Co
Priority date: 2004-05-21
Filing date: 2004-05-21
Publication date: 2005-11-24

Abstract

A carrying strap and method of making wherein the strap is adapted to support a load and includes a flexible webbing material and a spring element that dissipates and attenuates the shocks and vibrations caused by bouncing of the load as it is carried. One embodiment of the carrying strap includes (1) an elongate length of flexible webbing material and (2) a spring element including a resilient material positioned adjacent to at least a portion of the flexible webbing material such that each of the resilient material and the section of flexible webbing material has a corrugated profile. In response to the load causing a shock force on the carrying strap, the spring element expands and contracts to absorb, attenuate, and/or dissipate the shock force caused by bouncing of the load as it is carried.

Description

TECHNICAL FIELD

The field of the present invention relates to carrying straps and, in particular, to shock-absorbing devices for carrying straps, carrying straps including such devices, and methods of making such devices and carrying straps.

BACKGROUND OF THE INVENTION

Carrying straps have long been used to carry a variety of loads, such as, for example, backpacks, golf bags, briefcases, mail pouches, rifles, luggage bags, and purses. These carrying straps are typically used over one or both of the user's shoulders or around the user's neck. Exemplary materials from which carrying straps are formed include nylon webbing, leather, neoprene, and a variety of inelastic materials. Recently, increased attention has been directed to the importance of designing carrying straps that are ergonomically comfortable for the user when carrying heavy loads over long distances or rough terrain.
One source of user discomfort arises when the up-and-down motion that a user experiences when walking translates into uncomfortable changes in the load pressure of the carrying strap(s) upon the user's shoulder(s) or neck, which causes the load to slightly bounce up and down. The shock or stress resulting from carrying a load for extended periods of time while moving, e.g., during long walks, is absorbed by the user's body, often causing pain, discomfort, and can lead to physical damage to the user's body. Such discomfort and fatigue result from the carrying strap's inability to “give” as the user's shoulder or neck bobs up and down.
Prior art attempts to make carrying straps more ergonomic include making them adjustable in length and adding padding that provides ergonomic comfort to the user. One known carrying strap is formed of highly elastic neoprene material. However, the high degree of elasticity of neoprene accentuates the bounce effect and provides little control over the amount of bounce imparted to the user. This results in significant shoulder and/or neck stress and discomfort.
The present inventor has recognized the need for shock-absorbing, load-bearing carrying straps that dissipate and attenuate the impact of shocks that occur when a user carries a load.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric view of a carrying strap according to a first preferred embodiment.
FIG. 2 is a side view of the carrying strap of FIG. 1.
FIG. 3 is a top view of the carrying strap of FIG. 1.
FIG. 4 is an isometric view of a carrying strap including a spring element according to a second preferred embodiment.
FIG. 5 is a side view of the carrying strap of FIG. 4.
FIG. 6 is a top view of the carrying strap of FIG. 4.
FIG. 7 is an end view of a detachable spring element for a carrying strap according to a preferred embodiment.
FIG. 8 is an isometric view of a carrying strap according to a third preferred embodiment.
FIGS. 9A, 9B, and 9C are side view drawings of the carrying strap of FIGS. 4-6 shown in three different states of expansion: static, exposed to a partial load, and exposed to a heavy load.
FIGS. 10A, 10B, and 10C are schematic drawings of different embodiments of a carrying strap attached to various exemplary loads.
FIGS. 11A and 11B are respective isometric and side view drawings of one embodiment of a carrying strap having a second strap member designed to provide increased control over the amount of stretch of which the carrying strap is capable.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

A carrying strap according to a preferred embodiment is adapted to be attached to a load and includes a flexible webbing material and a spring element that dissipates and attenuates the shocks and vibrations caused by bouncing of a load as it is carried. One embodiment of the carrying strap includes (1) an elongate length of flexible webbing material and (2) a spring element made of a resilient material and positioned adjacent to at least a portion of the flexible webbing material such that each of the spring element and the portion of flexible webbing material has a corrugated profile.
When a shock force (caused, for example, by bouncing of the load as it is carried) is placed on the carrying strap, the spring element expands and contracts to absorb, attenuate, and/or dissipate the shock force, thereby minimizing its effect on the person carrying the load. The greater the shock force (or load weight), the greater the amount of elongation or stretch. By stretching, elongating, or expanding as the user's shoulder bobs up and down, sharp pressure peaks between the carrying strap and the user's body are prevented, and the pressure load on the bones, muscles, and tissue of the user can be more evenly distributed and maintained at a value sufficiently low to be readily adsorbed by the spring element of the strap, thereby providing long-term comfort to the user. The spring element thereby minimizes bounce fatigue. As the user's shoulder bobs up and down at a normal walking or hiking pace, the spring element repeatedly stretches and contracts to eliminate or moderate peak loads applied to the user's shoulder and stress points and thereby maintains the tension at a substantially uniform value without cyclic pressure peaks coinciding with the user's walking pace. This stretching reduces the incidence of bounce fatigue and enables the user to carry a load on a shoulder strap for an extended period of time. The magnitude of shock, stress, or bounce absorption is generally relative to the weight of the load being carried and the characteristics of the terrain across which the load is carried. Further, the ability of the carrying strap to expand dissipates the stress felt at a point of contact with the shoulder or neck. Rather than having a concentrated point of stress contacting the shoulder or the neck, the stress is better distributed throughout the strap.
The preferred embodiments will now be described with reference to the drawings. FIGS. 1-3 illustrate a carrying strap 1 including a length of flexible webbing material 2 having opposed terminal ends 4 and 6. One or both of terminal ends 4 and 6, respectively, are adapted to be attached to a load 8 (shown in FIGS. 10A, 10B, 10C, and 10D) and/or a connector 10 (shown in FIGS. 10A, 10B, 10C, and 10D) that connects flexible webbing material 2 to load 8. The flexible webbing material 2 includes opposed upper and lower surfaces 12 and 14, respectively, each of which is substantially flat and a longitudinal axis 16. A portion of flexible webbing material 2 is positioned adjacent to a spring element 30 such that both spring element 30 and the portion of flexible webbing material 2 have a substantially serpentine, wavy, or sinusoidal pattern that forms a corrugated profile that includes at least one period. The substantially serpentine, wavy, or sinusoidal pattern is formed by at least one wave 42 extending along longitudinal axis 16. Each wave 42 includes a ridge 44 adjacent to a groove 46. Spring element 30 may include multiple waves 42 comprising alternating ridges 44 and grooves 46. Waves 42 may be continuous along the width of spring element 30 or may be discontinuous. Waves 42 form the corrugated profile and provide slack in webbing material 2. Further, waves 42 provide a degree of longitudinal elasticity to carrying strap 1, which attenuates and dissipates at least a portion of the shock force and which provides a degree of extension and expandability to carrying strap 1. In one embodiment, the corrugated profile of flexible webbing material 2 and the corrugated profile of spring element 30 have substantially equal periodicities that are in phase with one another.
Spring element 30 includes an upper surface 32 and a lower surface 34 and a first terminal end 36 and a second terminal end 38.
Exemplary connectors 10 include additional straps, snap fasteners, rotatable hooks, swivel snap hooks, swivels, D-rings, per loop connectors composed of quarter-inch webbing, flip-over and lockable straps, side-release-type buckles, and other connectors 10 that facilitate easy connection to and disconnection from load 8. Additionally, connector 10 may be molded directly to the webbing material 2, or webbing material 2 may be connected to itself using a velcro or tri-glide connector. Spring element 30 may also include side-release-type buckles that, for example, allow the user to squeeze the sides of the buckles and thereby disconnect load 8 from carrying strap 1.
Flexible webbing material 2 may be any of a variety of elastic materials having varying coefficients of elasticity. Flexible webbing material 2 is preferably a material that can carry heavy loads without tearing. Exemplary preferred flexible webbing materials 2 include nylon, polypropylene, leather, synthetic leather, canvas-like fabrics such as washable denim, rubber, natural rubber, polyester, microfiber-based material, ethylene-propylene-diene-monomer (EPDM), Hypalon®, neoprene, elastic polyester, polyurethane (such as TEXIN®, PELLETHANE®, and ESTANE®), styrene butadiene rubber (SBR), silicone, Viton®, flexible thermoplastics, thermoplastic rubber (such as Tefabloc®), and fabric-backed vinyl plastic. Flexible webbing material 2 may be decorated to include, for example, a trademark, the manufacturer's name, the product's trade name, a design, contrasting colors, non-slip ridges, accessory attachment points, accents, or other similar features. Further, flexible webbing material 2 may be reverse tapered. The tensile strength of flexible webbing material 2 generally dictates the tensile strength of carrying strap 1. A preferred tensile strength is between 500 lbs and 10,000 lbs.
The length and thickness of flexible webbing material 2 may be adjusted to accommodate various types of load 8, weights of load 8, movement of the user, terrain on which load 8 will be carried, and other factors. Exemplary length, width, and thickness ranges where carrying strap 1 is used as a backpack strap are as follows: flexible webbing material 2 may have a length of between about 50 mm (about 2 inches) and about 915 mm (about 36 inches) (from terminal end 4 to terminal end 6), a width of about 0.762 mm (about 0.030 inch) and about 76 mm (about 3 inches), and a thickness 22 of between about 0.25 mm (about 0.01 inch) and about 0.318 mm (about 0.125 inch).
Spring element 30 includes a resilient material such as, for example, a thermoplastic material, rubber, natural rubber, a flexible resin compound, or a decorative material or fabric. The resilient material may be a moldable material. For example, the resilient material may be applied onto flexible webbing material 2 via an overmolding process. Spring element 30 may include a translucent resilient material that is designed to change color as it stretches in response to a shock force. For example, a yellow-colored elastomeric spring element may be overmolded onto a blue webbing material such that as the resulting carrying strap stretches, the yellow elastomeric spring element becomes more translucent and the stretched carrying strap looks green. The portion of carrying strap 1 including spring element 30 preferably maintains a high degree of flexibility. As shown in FIGS. 1-3, flexible webbing material 2 shows through portions of spring element 30.
The waves 42 of spring element 30 are elastically deformable such that a visible change in length of spring element 30 occurs when load 8 imparts stress in spring element 30. Imparting load-based stress in spring element 30 causes waves 42 to separate, flatten, and/or expand in response to the stress. Following dissipation or attenuation of at least a portion of the magnitude of the stress placed in carrying strap 1, spring element 30 contracts back to its original position. In this embodiment, carrying strap 1 includes visible stretch characteristics and shock-absorbing qualities.
Spring element 30 may be tailored to provide a desired magnitude of shock-absorbing capacity. For example, carrying strap 1 may be designed to be used with a load having a specified weight range. Exemplary methods by which carrying strap 1 can be so designed include the following: (1) including multiple spring elements 30 on carrying strap 1 such that each spring element 30 provides a specific magnitude of shock attenuation and dissipation so that the additive effect provides a desired magnitude of shock attenuation and dissipation; (2) including on carrying strap 1 a single spring element 30 having a resilient material thickness designed to provide a specific magnitude of shock attenuation and dissipation; (3) including on carrying strap 1 a single spring element 30 having a specific number of waves 42, which number has been calculated to provide a desired magnitude of shock attenuation and dissipation; (4) including on carrying strap 1 a single spring element 30 having ridges 44 a desired height above webbing material 2 such that a specific magnitude of shock attenuation and dissipation is achieved (the greater the height above webbing material 2, the greater the stretch and elongation and the smaller the height above webbing material 2, the less in-line stretch and elongation); (5) and/or a combination of these methods. Prior art carrying straps, such as a neoprene strap, are unable to provide this degree of control over the amount of shock attenuation and/or dissipation.
In another embodiment, both upper surface 32 and lower surface 34 of spring element 30 include the substantially serpentine, wavy, or sinusoidal pattern. In one implementation of this embodiment, multiple ridges 44 and grooves 46 are phase-displaced relative to each other such that each ridge 44 on upper surface 32 is spatially aligned with groove 46 on lower surface 34. This embodiment provides excellent visible stretch characteristics and shock-absorbing qualities. This visibility of the carrying strap's attenuation and dissipation of shock forces is another advantage over prior art carrying straps. Because waves 42 of spring element 30 may visibly stretch, flatten, elongate, and/or recoil, the user can see the shock-absorption, attenuation, and/or dissipation occurring. This provides a desirable visual appeal.
Alternatively, only one of upper surface 32 or lower surface 34 may include the substantially serpentine, wavy, or sinusoidal pattern.
FIGS. 4-6 illustrate a second preferred embodiment of carrying strap 1 in which at least one tab (or skirt) 40 is disposed on spring element 30. Tabs 40 may have various shapes, thicknesses, and sizes. The size, shape, and dimensional presence of tabs 40 facilitates the shock-absorbing and/or load-bearing capacity of carrying strap 1. Tabs 40 may be affixed (e.g., by overmolding, stitching, or gluing) to flexible webbing material 2 to act as mechanical anchors for spring element 30. One or both of tabs 40 may be decorated, for example, to include a trademark, the manufacturer's name, the product's trade name, a design, a contrasting color, non-slip ridges, accessory attachment points, an impression, an integrally molded logo, accents, or another similar feature. The decoration may, for example, be formed by placing the same or another moldable material into or onto tabs 40 of spring element 30. Additionally, the portion of flexible webbing material 2 facing or extending through spring element 30 may have a shape, thickness, and/or size that is tailored to fit spring element 30 (or vice versa). For example, a portion of flexible webbing material 2 may be tapered to fit into a tapered tab 40.
Spring element 30 may include multiple webbing material waves 42 extending along longitudinal axis 16 and at least one resilient material rib 50 disposed generally parallel to longitudinal axis 16. As shown in FIG. 7, spring element 30 may include multiple resilient material ribs 50, and each resilient material rib 50 may extend along and/or span substantially all of webbing material waves 42. Carrying strap 1 of FIG. 7 includes three ribs 50. Terminal ribs 50 _tmay have resilient material extending outwardly past the edge of webbing material 2. Further, resilient material ribs 50 may be formed on each of upper surface 32 and lower surface 34 or only one of upper surface 32 and lower surface 34. Ribs 50, like waves 42, separate, flatten, and/or expand in response to the placement of load-based stress on spring element 30. Following dissipation or attenuation of at least a portion of the magnitude of the stress placed in the carrying strap, ribs 50 contract back to their original shape. In one embodiment, ribs 50 provide visible indication of movement when stretching and contracting, resulting in a unique aesthetic appeal.
Carrying strap 1 may include multiple spring elements 30, and multiple carrying straps 1 may be affixed to one another to form a carrying strap of a desired length or having a desired magnitude of shock-absorption.
Spring element 30 may be affixed to the length of flexible webbing material 2, by a suitable mechanism such as overmolding, stitching, or gluing, or it may be removably connected thereto. Further, spring element 30 may be formed of a colored material or otherwise have a color that has a high contrast with flexible webbing material 2 such that the user's attention is drawn to spring element 30. This is especially useful in embodiments in which the elongation of spring element is visible to the user.
In one embodiment, spring element 30 is overmolded onto flexible webbing material 2 to form a wavy length of flexible webbing material embedded in a molded body of thermoplastic rubber material. In this implementation, spring element 30 is affixed to flexible webbing material 2 to form an integral molded unit that forms a composite, shock-absorbing structure.
One exemplary method by which spring element 30 may be overmolded onto elongate length of flexible webbing material 2 involves injection molding. A portion of flexible webbing material 2 is clamped in a mold cavity, and the mold cavity surfaces are shaped to bend flexible webbing material 2 into a serpentine shape upon closing of the mold. Closing of the mold holds the elongate length of flexible webbing material 2 tightly in place such that injection of the thermoplastic material or rubber will not cause flexible webbing material 2 to shift during processing. The resilient material may be injected into the cavities of the mold at a temperature sufficient to keep resilient material in flowable or liquid form.
Forming spring element 30 by overmolding has various advantages. One possible advantage is that expensive labor is eliminated because an automated line can be formed to manufacture carrying strap 1, which may avoid labor-intensive sewing steps. For example, flexible webbing material 2 can be fed from a spool cross-wise onto a platen of a mold. As described above, the mold will close on a portion of flexible webbing material 2 and spring element 30 will be injection molded onto the portion of flexible webbing material 2. Once the mold is opened, carrying strap 1, onto which has been formed spring element 30, is advanced relative to the mold such that either a new carrying strap or a different portion of carrying strap 1 is placed within the mold. The cycle is then repeated to form another spring element 30. In this way, carrying straps having either a single or multiple spring elements 30 may be formed. The automated line may also include a knife or other cutting device that cuts each carrying strap when it attains a predetermined length. In this way, multiple carrying straps 1 may be efficiently and inexpensively formed with minimal human interaction.
While forming spring element 30 by injection molding has various advantages, spring element 30 may also be formed by extrusion or other thermoforming techniques.
In one embodiment, at least a portion of flexible webbing material 2 onto which spring element 30 is formed is permeable such that the liquid resilient material overmolded onto flexible webbing material 2 seeps into and through the holes, pores, or voids in flexible webbing material 2 to form a mechanical bond between spring element 30 and flexible webbing material 2. Spring element 30, when injected in a molten state, coheres to upper surface 12 and lower surface 14 of flexible webbing material 2 resulting in a physical interconnection of flexible webbing material 2 and spring element 30. More specifically, the permeability of flexible webbing material 2 permits the liquid resilient material to encroach into and through the web of woven filaments of flexible webbing material 2. This encroachment of the resilient material tightly anchors spring element 30 onto flexible webbing material 2, thereby enhancing the shock-absorbing properties of the resulting carrying strap 1. The permeable portion of flexible webbing material 2 may encompass the entire length of flexible webbing material 2, only the portion in contact with spring element 30, only the portion in contact with tabs 50, or another portion of flexible webbing material 2. Flexible webbing material 2 may be formed of an open weave material. The portion of flexible webbing material 2 may have a roughened surface texture (not shown) that enhances the ability of the resilient material of spring element 30 to intermesh with and grip the surfaces of flexible webbing material 2. Alternatively, flexible webbing material 2 may include perforations (not shown) extending from upper surface 12 to lower surface 14 of flexible webbing material 2 such the molten resilient material flows into the perforations and spring element 30 is anchored on flexible webbing material 2. In all of these (and other) embodiments, injecting the resilient material in a molten state under sufficiently high pressure may cause the molten resilient material to permeate and interlock with any perforations, fibers, pores, woven strands, or roughened upper 12 or lower 14 surface features.
Alternatively, a portion of spring element 30 may be stitched or glued onto flexible webbing material 2, for example, at tabs 40 of first and second terminal ends 36 and 38, respectively. Because limiting the longitudinal stretchability of spring element 30 minimizes the shock-absorbing action of carrying strap 1, spring element 30 is preferably glued and/or stitched to flexible webbing material 2 to maximize the longitudinal stretchability of spring element 30. Other means of attaching spring element 30 to flexible webbing material 2 include, for example, fabric adhesive, rivets, snaps, and staples.
One exemplary method by which spring element 30 may be stitched or glued onto flexible webbing material 2 involves sliding a preformed spring element onto flexible webbing material 2 from one of the terminal ends 4 and 6. Once spring element 30 is slid into its desired location, spring element 30 and flexible webbing material 2 are preferably tightly held in position so that they do not shift during stitching or gluing. A portion of spring element 30, e.g., one or both of tabs 40, is then sewn or glued onto flexible webbing material 2. In one implementation of this embodiment, first and second terminal ends 36 and 38 of spring element 30 include tabs 40 on which the stitching or gluing is concentrated. This stitching or gluing of tabs 40 to flexible webbing material 2 forms a unitary shock-absorbing structure that, when finished, by appropriate choices of components, provides stretch characteristics and shock-absorbing qualities.
In an embodiment in which spring element 30 is removably connected to flexible webbing material 2, connection of spring element 30 to flexible webbing material 2 can be effected in a variety of ways, for example, by threading flexible webbing material 2 through spring element 30. Spring element 30 is preferably slid onto elongate length of flexible webbing material 2 such that opposing terminal ends 4 and 6, respectively, of flexible webbing material 2 extend from first and second terminal ends 36 and 38, respectively, of spring element 30.
As shown in FIG. 8, spring element 30 may include at least one strip 54 of resilient material positioned adjacent to the portion of flexible webbing material 2 or comprising an apex of ridge 44 of wave 42. This embodiment is especially useful where spring element 30 is overmolded onto flexible webbing material 2 because strips 54 form channels along which excess resilient material may flow during molding of spring element 30. Further, strips 54 are especially useful in embodiments in which the manufacturer wishes to control the shock-absorbing capacity of carrying strap 1. Because strips 54 include additional resilient material, they increase the magnitude of resistance to shock of spring element 30 and thus of carrying strap 1. Adding strips 54 and controlling their thickness facilitates control of the magnitude of the overall shock-absorbing capacity of carrying strap 1. Strips 54 preferably extend between adjacent ribs 50.
Spring element 30 may comprise a molded web with two tri-glides that connect to an existing carrying strap.
FIGS. 9A, 9B, and 9C are side views of one embodiment of a carrying strap at three different states, respectively: static, exposed to a partial load, and exposed to a heavy load. These figures show the varying amount of elongation of spring element 30 in response to varying amounts of shock force. When a shock force (caused, for example, by bouncing of load 8 as it is carried) is placed on carrying strap 1, spring element 30 expands and contracts to absorb, attenuate, and/or dissipate the shock force and thereby minimize its effect on the person carrying load 8.
In one embodiment, flexible webbing material 2 is formed of a material that is significantly less elastic than the resilient material used to form spring element 30. The combination of the lower elasticity material in the strap portion of carrying strap 1 and the higher elasticity material in the spring element portion of carrying strap 1 results in a carrying strap that combines the advantages offered by each material. For example, when exposed to a heavy load, flexible webbing material 2 may reach a maximum stretch point such that waves 42 of flexible webbing material 2 become substantially flattened and the section of flexible webbing material 2 adjacent to spring element 30 is fully extended. In one implementation, flexible webbing material 2 has a tensile strength that is greater than that of spring element 30. The strength and relative inelasticity of flexible webbing material 2 prevent spring element 30 from over-stretching past its yield point.
As shown in FIGS. 10A-10C, one preferred placement of spring element 30 on carrying strap 1 is such that spring element 30 is disposed adjacent to the user's thoracic or chest area so that when the user is carrying load 8, spring element 30 does not uncomfortably rub against the user's shoulder(s).
Embodiments of the carrying strap may be used to carry various types of loads, such as, for example, musical instrument cases; golf bags; camera bags and accessories; sports bags; airline carry-on bags; luggage; military duffel bags; postal carriers bags; knapsacks; infant harnesses; backpacks; briefcases; bungee cord; rifles; lawn equipment including, for example, weed wackers and leaf blowers; purses; pens; cell phones; and accessory bags. For example, FIGS. 10A-10C are schematic drawings of different embodiments of a carrying strap attached to various exemplary loads, such as each of a camera, a rifle, and a briefcase, respectively.
A carrying strap having a spring element as described above may optionally be used in connection with a padding or cushion on the carrying strap, such as, for example, a padding adapted to cushionably rest upon the shoulder of the user. Alternatively, as shown in FIGS. 11A and 11B, the carrying strap could include a second strap member 100 that is attached to the flexible webbing material to provide increased control of the amount of stretch of which carrying strap 1 is capable. For example, second strap member 100 may be formed such that the complete assembly has a pre-designed limit to its ability to stretch in the longitudinal direction. In one embodiment, second strap member 100 may comprise a second piece of flexible webbing material 2. Alternatively, second strap member 100 may be formed of a non-stretchable material providing stiffness and mechanical strength sufficient to support load 8 when flexible webbing material 2 and spring element 30 are stretched past a predefined point. Second strap member 100 may be attached to carrying strap 1 by mechanical hardware, a mechanical fastener, sewing, or a combination thereof. Further, as shown in FIG. 10, the opposed terminal ends of carrying strap 1, which at least one of which is adapted to be attached to a load, may be looped around a connecting piece that attaches carrying strap 1 to another carrying strap, another strap, etc that is attached to a load.
It will be obvious to those having skill in the art that many changes may be made to the details of the above-described embodiments without departing from the underlying principles of the invention. The scope of the present invention should, therefore, be determined only by the following claims.

Claims

1. A carrying strap having opposed terminal ends, at least one of which is adapted to be attached to a load such that the carrying strap may be used to carry the load, comprising:

a length of flexible material; and

a spring element including a resilient material positioned adjacent to a portion of the length of flexible material such that each of the resilient material and the section of the length of flexible material has a corrugated profile that expands when a load is applied to the strap.

2. The carrying strap of claim 1, in which the resilient material is overmolded onto the section of flexible material.

3. The carrying strap of claim 1, in which the spring element is sewn or glued onto the section of flexible material.

4. The carrying strap of claim 1, in which the spring element is slidable along the length of the flexible material.

5. The carrying strap of claim 1, in which the corrugated profile of the section of flexible material and the corrugated profile of the resilient material have substantially equal periodicities and are in phase with one another.

6. The carrying strap of claim 1, in which the flexible material is selected from a group consisting essentially of nylon, polypropylene, leather, synthetic leather, canvas-like fabrics, rubber, natural rubber, polyester, microfiber-based materials, EPDM, Hypalon®, neoprene, elastic polyester, polyurethane, SBR, silicone, Viton®, flexible thermoplastics, and fabric-backed vinyl plastic.

7. The carrying strap of claim 1, in which the resilient material is selected from a group consisting essentially of a thermoplastic material, rubber, natural rubber, a flexible resin compound, a decorative material or fabric, and another moldable material.

8. The carrying strap of claim 1, in which the spring element includes an upper surface and a lower surface, each of which includes a wavy pattern that forms a corrugated profile.

9. The carrying strap of claim 1, in which the spring element includes at least one resilient material rib disposed generally parallel to a longitudinal axis of the carrying strap.

10. A carrying strap, comprising:

a length of flexible webbing material having a longitudinal axis and a corrugated portion, the corrugated portion including multiple webbing material waves disposed along the longitudinal axis; and

a resilient material positioned adjacent to the webbing material waves such that each of the resilient material and the corrugated portion has a corrugated shape.

11. The carrying strap of claim 10, in which the resilient material forms at least one resilient material rib disposed generally parallel to the longitudinal axis.

12. The carrying strap of claim 11, in which the resilient material rib extends along substantially all of the webbing material waves.

13. The carrying strap of claim 11, in which the spring element includes first and second resilient material ribs on opposite sides of the flexible webbing material.

14. The carrying strap of claim 10, in which the resilient material is overmolded onto the corrugated portion.

15. The carrying strap of claim 10, in which the spring element is slidable along the length of the elongate flexible webbing material.

16. The carrying strap of claim 10, in which the flexible webbing material is selected from a group consisting essentially of nylon, polypropylene, leather, synthetic leather, canvas-like fabrics, rubber, natural rubber, polyester, microfiber-based materials, EPDM, Hypalon®, neoprene, elastic polyester, polyurethane, SBR, silicone, Viton®, flexible thermoplastics, and fabric-backed vinyl plastic.

17. The carrying strap of claim 10, in which the resilient material is selected from a group consisting essentially of a thermoplastic material, rubber, natural rubber, a flexible resin compound, a decorative material or fabric, and another moldable material.

18. The carrying strap of claim 10, in which the spring element includes an upper surface and a lower surface, each of which include a corrugated portion.

19. A carrying strap, comprising:

a length of flexible webbing material having opposed upper and lower surfaces with a section of the webbing material having a corrugated structure formed by alternating ridges and grooves in each of the upper and lower surfaces, the grooves in the upper surface being in phase with the ridges in the lower surface and the grooves in the lower surface being in phase with the ridges in the upper surface; and

a spring element including a resilient material positioned adjacent to at least a portion of the corrugated structure of the flexible webbing material, the spring element having a corrugated profile formed by alternating ridges and grooves that are generally in phase with the alternating ridges and grooves of the corrugated structure of the flexible webbing material so that the spring element and the corrugated structure of the flexible webbing material flatten in response to application of a tensile bounce load, thereby attenuating the impact of the load.

20. The carrying strap of claim 19, in which the spring element further includes a rib disposed longitudinally along the length of the flexible webbing material.

21. The carrying strap of claim 19, in which the flexible webbing material is selected from a group consisting essentially of nylon, polypropylene, leather, synthetic leather, canvas-like fabrics, rubber, natural rubber, polyester, microfiber-based materials, EPDM, hypalon®, neoprene, elastic polyester, polyurethane, SBR, silicone, Viton®, flexible thermoplastics, and fabric-backed vinyl plastic.

22. The carrying strap of claim 19, in which the resilient material is selected from a group consisting essentially of a thermoplastic material, rubber, natural rubber, a flexible resin compound, a decorative material or fabric, and another moldable material.

23. The carrying strap of claim 19, in which the resilient material is overmolded onto the corrugated structure.

24. The carrying strap of claim 19, in which the spring element is slidable along the length of the flexible webbing material.

25. A method of forming a carrying strap, comprising:

clamping a portion of an elongate length of flexible webbing material to form a webbing material portion having a corrugated profile that extends longitudinally along the webbing material portion; and

overmolding a resilient material onto at least a portion of the webbing material portion to form a composite spring element having a corrugated profile that generally follows the corrugated profile of the webbing material portion.

26. The method of claim 25, in which a portion of the flexible webbing material includes pores through which the resilient material wicks during the overmolding process to anchor the spring element on the portion of the flexible webbing material.

27. The method of claim 25, in which a portion of the flexible webbing material includes perforations through which the resilient material wicks during the overmolding process to anchor the spring element on the portion of the flexible webbing material.

28. A method of forming a carrying strap from a length of flexible webbing material comprising:

forming a section of the flexible webbing material into a corrugated profile; and

overmolding a resilient material onto the section to form a composite spring element having a corrugated profile that generally follows the corrugated profile of the flexible webbing material portion.