The inventive subject matter is generally directed to footwear. In some embodiments, the inventive subject matter is directed to footwear having a traction sole, especially a sole for use in the sport of golf. The footwear includes a sole with a rocker sole that requires a user to engage core muscles and balance. In other embodiments, the inventive subject matter is directed to a rocker shoe with a midsole based on certain spring systems.
The concept of walking with a rolling action is said to result in a comfortable heel strike, creating a natural instability that can help the body generate muscle activity in the lower limbs. This action can be facilitated by a shoe with a pivot axis positioned between the heel and toes. For example, the axis may be based on a convexly curved sole with its integrated balancing area requiring an active and controlled rolling movement that can help the body to improve balance and posture while standing and walking. Footwear enabling this particular way of walking has been described, for example, in U.S. Pat. No. 6,341,432 which is hereby incorporated by reference in its entirety for all purposes. As illustrated in
When the shoe 1 is placed on a support surface in the vicinity of the pivot axis 21, it tilts around the pivot axis 21 with the ball or toe area 10 of the shoe 1 on the support. As a result, the foot and the lower leg are displaced slightly forward and the knee is automatically bent slightly. A leg bent at the knee accepts the impact load through the bones of the skeleton and the surrounding musculature without the impact load being transmitted to the joints or the spinal column The prior art shoe produces a rounding effect, in other words a rolling action, as it is placed on the support so that the impact load exerted on the sensitive joints or on the spinal column is considerably reduced. In the standing phase, the wearer of the shoe 1 is also placed in a therapeutic posture, in other words a posture with the knees forced to bend at an angle so that the spinal column is also relieved of a load when standing.
Other examples of rocker shoes include US 2011/0078923, US 2011/0035960, US 2010/0263233, US 2010/0281716, US 2009/0151201 and WO 2006/065047, which are hereby incorporated by reference in their entireties for all purposes.
Because of the pivot axis in rocker shoes, these shoes cause some natural instability that forces users to engage core muscles. The pivotable bottom structure acts on major parts of the postural and supporting musculature, because the body must now be actively kept in balance. To maintain a stable standing position, continuous minimal compensating movements are required. In particular, neglected muscles are trained, posture and gait pattern are improved, and the body is toned and shaped.
Unfortunately, the prior art shoes have not been adapted for special purpose athletic shoes that have traction elements, e.g., spike or cleats, such as golf shoes, football shoes, soccer shoes, baseball shoes, track shoes, etc. The inclusion of traction elements, such as spikes and cleats is inconsistent with and counterintuitive to the notion of a smooth, rocker motion, so the lack of rocker shoes incorporating traction elements is not surprising. Hereinafter, golf shoes will be discussed as a representative form of traction footwear, although some or all the discussion concerning golf shoes will apply to other kinds of shoes with traction elements.
As used herein a “traction element” generally refers to relatively discrete structural components on the ground-engaging surface of a sole, such as spikes and cleats. For golf, baseball, football, and soccer shoes, the traction elements protrude substantially from their supporting surface and are intended to dig into softer surfaces such as grass, dirt, mud, and artificial surfaces such as tracks.
In golf sports, desired features include that the shoes are lightweight, support the foot, and have a spike formation that offers the desired traction and stability on a golf course. In addition to providing support and comfort to the foot while walking, golf shoes support and stabilize the golfer when the golfer is swinging and hitting the golf ball, resulting in a better posture and improved balance. Other desirable features for a golf shoe are a sole that allows the golfer to stand lower in the shoe, that provides a better feel for the course, and that provides a lower center of gravity. Again, all these desirable characteristics are counter to the notion of a rocker shoe with a pivot axis.
There have been several attempts to improve cushioning and support in conventional athletic shoes. For example, polymer spring units have been placed in portions in the sole, particularly the heel portion, and in some cases the forefoot portion. See, for example, U.S. Pat. No. 4,910,884; U.S. Pat. No. 5,337,492; U.S. Pat. No. 5,461,800; and U.S. Pat. No. 6,625,905, which are hereby incorporated by reference in their entireties for all purposes. However, despite the availability of many kinds of conventional shoes, golf-related injuries are a common problem often caused by improper golf swing or improper posture. Associated activities such as pushing and pulling carts or carrying bags may also cause injuries. Moreover, golf is also a demanding sport that requires precise balance, timing and coordination of musculature through the golfer's swing. Therefore, there is an ever present need for improved training devices that will help golfer's improve their swings and maintain posture.
Accordingly there is a need for an improved sole assembly for traction footwear, such as golf shoes, that includes the features of a rocker sole to enhance awareness of balance, posture, and gait patterns, as well as improving coordination and providing a better feel for the course.
The inventive subject matter is generally directed to a sole assembly comprising a plurality of traction elements disposed on a ground-facing surface of the sole assembly, and wherein the sole assembly is configured to provide a rocker effect. In some embodiments, the inventive subject matter is directed to a sole assembly that includes a spring system based on a semi-rigid polymer shaped to provide the rocker effect. In some embodiments, the inventive subject matter is directed to a golf shoe with a sole profile having a geometric shape that provides a roll-over effect according to rocker shoe technology and wherein the sole profile is optimized to convey the benefits of rocker shoe technology to golf specific activities.
The foregoing is not intended to be an exhaustive list of embodiments and features of the inventive subject matter. Persons skilled in the art are capable of appreciating other embodiments and features from the following detailed description in conjunction with the drawings.
The following figures show embodiments according to the inventive subject matter, unless noted as showing prior art.
Representative embodiments according to the inventive subject matter are shown in
According to one embodiment of the invention, a sole assembly 4 for a shoe 1 comprising a foot-supporting element and a ground-engaging element is provided. The foot-supporting element 6 and the ground-engaging element 8 are separated in vertical direction by means of a spring system 7 and interconnected at least at the toe end 13 and heel end 14 of the sole assembly. The spring system is compressible in a vertical direction, in particular under vertical load exerted by a foot, so that at least a section of the ground-engaging element approaches the foot-supporting element in vertical direction under the vertical load. Further, the ground-engaging element is convexly shaped at least in a midfoot section. The midfoot section may be referred to as the longitudinal middle third section of the sole assembly. The convex or outwardly bent curvature of the ground-engaging element helps to provide a rocker action or tilting movement of the shoe. Further, the combination of the convex curvature and the spring system provides a feedback to the wearer of the shoe, thereby indicating the position of the actual balance point.
The ground-engaging element 8 is preferably generally plate shaped. As well, the foot-supporting element 6 may be plate shaped. Of course, in this regard the term “plate-shaped” does not refer to a flat or planar plate. Rather, as the ground-engaging element has a convex curvature, this element has the form of a bent plate. The foot-supporting element may be bent as well so as to contour or adapt to the foot sole.
In some embodiments, the inventive subject matter overcomes the aforementioned problems by providing traction footwear having an outer sole profile with a specific geometric shape and/or sole structure that allows a rocker effect. The sole profile and structure may be optimized to convey the benefits of rocker shoe technology to golf specific activities such as walking, performing T-shots, fairway shots, sand shots, and putting. By incorporating the features of rocker action in a golf shoe, the user experiences some instability, which leads to more awareness of balance and posture.
In another embodiment, the inventive subject matter is directed to a sole assembly 4 for traction footwear that includes a spring system 7 positioned between a foot-supporting element 6 and a ground-engaging element 8 so that the spring system provides a resiliently collapsible or compliant forefoot 16, midfoot 17, and/or heel section 18 to the sole assembly.
In some embodiments, the spring system 7 allows for a heel section 18 that is relatively more compressible than a midfoot section 17 and/or forefoot section 16 so that the sole can provide the rocker action.
In other embodiments, the foot-supporting element 6, ground-engaging element 8, and spring system 7 define a sole assembly 4 that provides a rocker shoe effect with a rolling action around a pivot axis 21. In further embodiments, the foot-supporting element and ground-engaging element may be separate elements that are functionally coupled by a resilient material and/or structure that serves as a deforming means from a heel area to the pivot axis, and coupled with a more rigid structure in a distal area forward of the pivot axis. In further embodiments, the foot-supporting element, ground-engaging element, and spring system may be integrated as a single monolithic piece. For example, they may all be molded together in a single shot or multiple shot injection molding process. Furthermore, different sections may have different materials or material properties to create a sole that is tuned to desired functions discussed herein.
A shoe 1, such as a golf shown in
The sole assembly 4 includes a foot-supporting element 6. In the embodiments shown in the figures, the foot-supporting element is a curved top plate. The foot-supporting element may be made of a rigid or semi-rigid material that will work as a stop surface 108 for the compliant or collapsible ground-engaging element in the heel section. In some embodiments, the foot-supporting element may include a thermoplastic polyurethane plate. Examples of other suitable materials include Urethane, Hytrel, Pebax, Nylon, etc. To provide both sufficient stiffness and resilience, a non-elastomeric material, at least for the load bearing sections of the ground-engaging element, may be used. For example, the ground-engaging element may be fabricated from a fiber-reinforced composite material. The foot-supporting element may have an upper surface and a lower surface. The upper surface of the foot-supporting element may support the foot directly or indirectly, for example, via an insole or an insert.
The sole assembly 4 further has a ground-engaging element or bottom layer 8.
The contours of the ground-engaging element 8 may have a shape that is substantially convex along a longitudinal cross-section of the sole when the shoe is in the unloaded state. The curved profile of the ground-engaging surface may have radial dimensions that are beneficial for playing golf.
In some embodiments, the apex of the convex shape may be positioned slightly off the center of the shoe along the longitudinal direction, for example the apex may be shifted towards the heel of the shoe. In other embodiments, the apex of the convex shape may be shifted towards the lateral or medial side of the shoe.
In other embodiments, the configuration of the sole assembly 4 may have any shape and structure that allows achieving desired degrees of rocking, stability, and controllability. For example, the sole assembly may have a geometrical form, such as polygonal shapes that approximate a curve, that allows for pivoting around an axis 21. In further possible embodiments, an outer sole structure may be a generally planar structure that allows for a yielding placement upon use within certain areas of the sole assembly. For example, this could be achieved by constructing areas with different durometer so that portion are collapsible or compressible under load to form a shape that allows pivoting.
The ground-engaging element 8 may be made of the same material as the foot-supporting element, for example a rigid or semi-rigid material with a hardness of 45-75 Shore D. A flexible and soft ground-engaging element could also be used. For example, a rubber or synthetic outsole material could be used and may be held in the convex shape by an intermediate spring system and/or a foot-supporting element.
In the embodiments shown, the ground-engaging element 8 is joined directly to the foot-supporting element 6 at a toe end 13 and at a heel end 14 of the sole assembly, and is integrated with a spring structure 7 to form a unitary sole assembly 4. In the finished shoe, the sides of the sole assembly may be left open or covered with any suitable material.
The rocker effect of the sole assembly 4 may be accomplished by a spring system 7 that provides a support zone in a forefoot section 16 to midfoot section 17 of a shoe and that allows for a collapsible or compliant zone 19 in a midfoot to heel section 18, for example, as shown in
The terms “spring system” and “spring” are used herein broadly to refer to any intermediate structure or material that stores mechanical energy in the sole and resiliently allows the sole to return to its original shape after deformation. This property may be conferred to the sole assembly by an elastic object or material that, when compressed in the vertical direction of the shoe sole, exerts a restoring force which tends to bring the object/material and shoe sole back to its original height. A spring system 7 may include any type of resiliently compressible mechanism such as a mechanical structure, for example coiled springs, tension springs, hinged springs, tubular springs, collapsible ribs, bladders, air bellows, etc., as well as any type of resiliently compressible filling material, such as an open-pored plastic materials or foams.
In some embodiments, the spring system 7 may be formed by the combination of the foot-supporting element 6, ground-engaging element 8, and an intermediate structure, e.g., structure 70, sandwiched between the foot-supporting element and ground-engaging element. In other embodiments, the spring system may be formed as an integral part of the foot-supporting element and/or ground-engaging element.
In the embodiments shown, the spring system 7 is formed by structurally integrated elements that show a wavy or undulating profile in a longitudinal cross-section of the sole. Accordingly, the spring system according to this embodiment of the invention comprises a spring having an undulating profile, e.g., a zigzag profile, which undulates along the longitudinal direction of the sole assembly. According to a refinement of the invention, the wavy pattern has a peak-to-peak length that increases towards the midfoot/heel sections of the sole assembly 4, or from the toe end towards the heel end.
The wavy pattern may have increasing wavelengths from a toe end 13 of the sole assembly 4 towards the pivot axis 21. The spring system 7 in the forefoot section 16 and partially in the midfoot section 17 forms the support zone of the shoe sole.
The rolling action of the sole assembly 4 is accomplished by a pivot 20 defined by pivot axis 21 which extends in the transverse direction of the sole assembly, for example, as shown in
The pivot axis 21 may be located in a midfoot section 17, which may extend over approximately one-third of the length of the shoe. For example, the pivot axis may be in an area between the lengthwise center of the shoe and a heel area.
The heel area pivots away upward around the pivot axis 21 when a user walks on a supporting surface. The shoe produces a rolling action as it is placed on a support surface so that the impact load exerted on the sensitive joints or on the spinal column is considerably reduced.
The wavy profile, shown in
Examples of suitable materials for a spring system 7 include resiliently compressible materials, such as urethane, Pebax, Hytrel, etc.
The ability to control the spring constant by the structural and/or material features can be used in various combinations to precisely control the performance characteristics of the sole assembly. Variations in the longitudinal profile, transverse profile, spring-thickness, spring shape, and wall thickness of the sole assembly permit control over the spring force in response to compression.
Optionally, the sole assembly 4 may include a foam material interspersed with the spring material, for example in the pockets or voids 37, 71 of tubular members 70. In some embodiments, the midsole may be free of foam material, for example a foot-supporting element, ground-engaging element, and sidewalls forming an open midsole that houses a spring system. In other embodiments, at least a portion of the midsole may be free of foam material, such as a heel portion. In further possible embodiments, a spring system may be embedded in a foam material, such as urethane, ethyl-vinyl-acetate (EVA), etc. In yet other embodiments, the midsole may include areas or pockets of a material, e.g. silicone, cast polyurethane. In some embodiments, the sole may include inserts such as one or more dampeners or bumpers to modify the dynamic response of the spring under a load. The inserts may be placed in open space for the spring structures such as voids or pockets 37, 71.
The footwear may have a traction sole, for example, configured for use in golf. Traction elements or cleats 30, 32 may be disposed on the ground-engaging element 8 and arranged in a pattern having a generally transverse alignment along the curved structure of the ground-engaging element. In some embodiments, the traction elements are located on the convex element just fore and aft of the pivot axis 21 or apex of the convex element, as seen in
The traction elements 30, 32 may be coupled to the ground-engaging element 8 via openings in the ground-engaging element that are adapted to receive and hold the cleats in place. In some embodiments, the traction elements may be spikes or cleats 32. The spikes may be made of a rigid material, or a relatively soft or firm but flexible material, as used in modern golf shoes. In other embodiments, the cleats may be permanently attached to the ground-engaging element, for example, as shown in
The ground-engaging elements 30, 32 may further include a random or repeating pattern of differences in elevations or ridges, which may contribute to traction between the shoe and the ground. For example,
The soles of the conventional rocker shoes may have a considerable thickness.
The golf shoe 1 further includes a shoe upper 5 that may be connected to the sole assembly, for example by adhesive bonding and via a solid and hard, but flexible insole. The shoe upper may be made of any suitable material, for example but not limited to leather, suede, neoprene, mesh, synthetics, or fabrics, or any combination of such materials.
The inventive subject matter is further directed to method for making a sole assembly for a golf shoe by molding a foot-supporting element, a spring system, and a ground-engaging element in a single-shot or multiple shot injection molding process, creating a monolithic midsole or entire assembly. Examples of single molded sole assemblies are shown in the attached figures. A monolithic structure may have a homogenous or heterogeneous composition. It may have varying material properties, such as varying density, durometer, spring rates, etc. For example, the spring effect may be accomplished by the design and shape of the sole assembly.
The inventive subject matter is further directed to a method for making a sole assembly by preparing a foot-supporting element and an ground-engaging element to form a sole assembly, and disposing a spring system between the foot-supporting element and the ground-engaging element so that the sole assembly comprises a geometric shape that is rounded convexly in the walking direction to convey the benefits of rocker shoe technology.
The inventive subject matter further contemplates a method for making such traction footwear and a method for using such traction footwear.
Persons skilled in the art will recognize that many modifications and variations are possible in the details, materials, and arrangements of the parts and actions which have been described and illustrated in order to explain the nature of the inventive subject matter, and that such modifications and variations do not depart from the spirit and scope of the teachings and claims contained therein.
All patent and non-patent literature cited herein is hereby incorporated by references in its entirety for all purposes.
Number | Date | Country | Kind |
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12004972.1 | Jul 2012 | EP | regional |
This application claims the benefit of and priority to U.S. Provisional Application Ser. No. 61/522,655, filed Aug. 11, 2011, by Hermann Oberschneider et al. entitled TRACTION FOOTWEAR, the contents of which are hereby incorporated by reference as if recited in full herein for all purposes.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US2012/050401 | 8/10/2012 | WO | 00 | 5/15/2014 |
Number | Date | Country | |
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61522655 | Aug 2011 | US |