Patent ID: 12250995

DETAILED DESCRIPTION

First Aspect

Rotatable Yoke with Vertical Tension Spring

Table of Reference Numerals:

First aspect of the shoe100Outsole101Midsole102Heel cushion area of the midsole103Rotatable collar yoke104Laces105Yoke eyelets106Tongue107Upper108Eyestay109Counter panel110Eyestay stitching111Counter panel stitching112“X” shaped stitching overlap113Anterior gusset114Posterior gusset115Narrow channel of upper116Interface between midsole and upper117Leg118Stitching in the rotatable collar yoke119Elastomeric overlay120Elastic zone121Rotation zone122Collar yoke adhesion zone123Superior rotation anchor zone124Inferior rotation anchor zone125Superior elastic anchor zone126Inferior elastic anchor zone127Zones of reduced bonding agents128Heel counter130Collar yoke stiffener131Collar yoke stiffener rotation interface132Eyestay and collar stiffener133Eyestay and collar stiffener rotation interface134Upper stiffener135Lace routing136Sock liner and padding system137Tension bearing stitching138Collar yoke cantilever stiffener139Variation of eyestay and collar stiffener140Full sidewall heel counter support141Yoke support with cantilevers142Overlapping U stitching143

Referring toFIGS.1through7, various side (A) and rear (B) views of a first aspect of footwear, for example, a shoe are shown from one perspective, for example, a left shoe100where a side of the shoe100not seen is assumed to be similar to the depicted side.FIG.1Ashows an external side view andFIG.1Ba rear view of the first footwear aspect.FIG.4shows a close-up of an ankle housing portion of shoe100.FIGS.2,3, and6show side (A) and rear (B) views of the first aspect with varying layers of materials removed to reveal internal components.FIG.5shows details concerning the placement and removal of bonding agents, andFIGS.7A and7Bshow details of tension-bearing stitching or caging.FIG.8will be referred to for a discussion of vectors for spring force, force exerted on a pivot point and shin force in the vicinity of a narrow channel116for the first footwear aspect.

FIGS.1through7are drawings, for example, of a modified high top athletic shoe100, with a rotatable collar yoke104and elastomeric overlay120. Shoe100may have an articulating joint at narrow channel116and an overlay rotation zone122as well as a tension spring device which is managed within an elastic zone121(FIG.4).

The posterior gusset115may remain exposed to highlight the dynamic quality of the shoe, or it may be covered by a stretch fabric to provide an aesthetic shoe designer with styling options and to prevent entry of sand and debris. Shoe100does not suffer from negative aesthetic impact of appendages or ancillary equipment. It can thereby maintain appearance qualities similar to other high top athletic shoes and offer an opportunity for delivering appealing ornamental designs that engage and interest buyers.

Basic Construction and Functionality

FIG.2shows shoe100with the elastomeric overlay120removed in side viewFIG.2Aand rear viewFIG.2B. These views demonstrate that a common high top athletic shoe may be modified to incorporate a point113of a narrow channel116(FIG.3) as will be described further herein. Shoe100has an anterior gusset114as well as a posterior gusset115. The addition of a posterior gusset115creates a narrow channel116of upper108between the anterior and posterior gussets114,115. Channel116defines a section above channel116which is formed as a rotatable collar yoke104. The narrow channel116and point113thus may be a pivot point for forces as discussed herein.

Collar yoke104may have a set of yoke eyelets106through which pass a set of laces105. Force from a lower leg118of a user can pass into a tongue107and then into the laces105and then into the eyelets106during use. A person wearing such a pair of shoes may notice the ability for the rotatable collar yoke104to follow the motion of their lower leg118above the ankle joint and the ability for the main body of the shoe100below the narrow channel116to follow the motion of their foot.

Force from the lower leg118may create rotation in the collar yoke104. Rotation of the collar yoke104may create a vertical range of motion at its rear. The vertical range of motion is visible at the rear opening of the posterior gusset115. This vertical range of motion creates an opportunity to insert a tension spring of various forms as further described below and mimic and supplement the behavior of the Achilles tendon.

The geometry of collar yoke104may be designed to allow the user to adjust firmness of laces105to determine the comfort on the collar aspect of the collar yoke104. The side walls of the collar yoke104may have stiffness which creates an additional length and oval shape to the collar yoke104than found in traditional collars. This results in less pressure being exerted upon the front and rear face of the lower leg118when the collar yoke104is tightened.

Shoe100, as will be discussed herein is capable of managing forces, storing and returning potential energy, capable of transmitting these forces into its anchor points, be durable, be comfortable, utilize commercially viable materials and manufacturing processes, have aesthetic qualities which positively differentiate it compared to similar shoe offerings, and provide other advantages as well. A footwear system represented by shoe100may endure secondary forces associated with the environment and activity the footwear is employed for and withstand thousands of gait cycles across a 10 to 50 degree or more range of ankle motion. An elastomeric overlay120, as described below, is one structural aspect of shoe100that is fully capable of fulfilling these requirements.

Overlay120Details

As shown inFIGS.1and4, shoe100may be constructed with use of an elastomeric overlay120. Overlay120may be, for example, a molded elastic element that contours to the shoe100and, referring toFIGS.4A and4B, shoe100has seven major functioning zones: an elastic zone121, an overlay rotation zone122, an inferior elastic anchor zone127, a superior elastic anchor zone126, an inferior rotation anchor zone125, a superior rotation anchor zone124, and a collar yoke adhesion zone123.

Overlay120may separate the several functioning zones into several discrete components differentiating shoe100. For example, elastomeric overlay120may comprise three separate overlays (not shown), with a bilateral set of rotation components122,124,125, a bilateral set of collar yoke adhesion zones123, and a set of elastic components121,126,127.

Elastic Force Management

Referring toFIG.4, elastic zone121is responsible for managing forces and storing a significant portion of the potential energy. Zone121runs near parallel to the Achilles tendon of a user of shoe100. Like the Achilles, zone121is stretched in dorsiflexion and collapses in plantar flexion. The length, thickness, material selection, manufacturing process and attachment qualities of the elastic zone121determine its spring rate and damping qualities. These qualities can be adjusted by a manufacturer to meet the anticipated needs of a given footwear application. Elastic zone may comprise a single elastic member or multiple elastic members.

The initial spring length provided by elastomeric overlay120is also influenced and controllable to a limited extent by the user and how tightly the user ties laces105. If the user does not tie laces105, as is frequently done by many people, elastic zone121may be rendered inoperative.

Elastic zone121is anchored below by an inferior elastic anchor zone127. The inferior elastic anchor zone127provides a lower attachment point for the elastic zone121as well as a surface area for adhesion to the rear of shoe100. Anchoring of elastic zone121may be accomplished by attachment to several components, including the external surface of the heel counter panel110, sandwiched between the heel counter panel110(FIG.2) and the rear of the shoe100, the heel counter130(FIG.6), the rear of the outsole101which may be connected via a contiguous molding, or alternate locations selected by the manufacturer. Fastening the inferior elastic anchor zone127to the rear of shoe100allows force from elastic zone121to be transmitted into the heel counter region which provides a mechanically advantageous means of inducing extension of the foot towards plantar flexion.

Referring again toFIG.4, elastic zone121may be anchored above by a superior elastic anchor zone126. The superior elastic anchor zone126may provide an upper attachment point for the elastic zone121as well as a surface area for adhesion to collar yoke104of shoe100. Adhesion of the superior elastic anchor zone126to collar yoke104allows force to be transmitted from the leg118, into shoe tongue107, into laces105, into yoke eyelets106, into collar yoke104, into superior elastic anchor zone126, and then into elastic zone121.

Rotation Force Management

Continuing to refer toFIG.4, zone122of the overlay120enables proper rotation of the collar yoke104, offers fulcrum qualities similar to a ball joint and is referred to herein as an overlay rotation zone122. This rotation zone122sits on top of narrow channel116of upper108that connects the main body of shoe100and collar yoke104. Flexibility in channel116enables collar yoke104to rotate in the sagittal plane. The overlay rotation zone122supplements channel116, providing improved management of forces, reduction in buckling, reduction in slumping, higher force management capability and higher longevity. Overlay rotation zone122provides an additional layer of material on top of the shoe's typical construction material (i.e.: vinyl, leather, fabric, etc) to withstand the forces of torque, compression, shear and tension associated with repeated rotation of collar yoke104. The overlay material of rotation zone122can function similarly to a human joint capsule by maintaining opposing joint surfaces in proper geometric position, enabling rotation, enabling a small amount of fore/aft joint laxity as in the ankle, and preventing untoward motion.

Overlay rotation zone122is anchored below by an inferior rotation anchor zone125. The inferior rotation anchor zone125provides an attachment point for the bottom of overlay rotation zone122as well as a surface area for adhesion to upper108. Adhesion of the inferior rotation anchor zone125to shoe100allows force from overlay rotation zone122to be transmitted into upper108and associated eyestay109of the shoe100. The inferior rotation anchor zone125may extend along the bottom opening of posterior gusset115and may extend down eyestay109as well as down upper108. This ability to distribute force among various shoe components provides a mechanically advantageous place to enable overlay rotation zone122to manage multiple forces. While in use, when elastic zone121of the elastomeric overlay120(FIG.1) is managing forces, these forces are counterbalanced by overlay rotation zone122working together with narrow channel116of upper108, which, in turn, are delivered into shoe100. The forces from overlay rotation zone122apply a force vector that is directed nominally down and to the front as received by inferior rotation anchor zone125.

The overlay rotation zone122is anchored above by a superior rotation anchor zone124. The superior rotation anchor zone124provides an attachment point for the top of overlay rotation zone122as well as a surface area for adhesion to collar yoke104. Adhesion of the superior rotation anchor zone124to collar yoke104of shoe100allows force from the overlay rotation zone122to be transmitted in and out of collar yoke104during use. In order for forces to be most effectively transmitted from a user's leg118to elastic zone121during use, they first receive leverage through the fulcrum defined by the overlay rotation zone122. The superior rotation anchor zone124applies forces from collar yoke104into overlay rotation zone122. The superior rotation anchor zone124may be geometrically designed to ensure proper bonding to collar yoke104, proper force transmission from the collar yoke104into the overlay rotation zone122, and reduction in buckling or slumping of collar yoke104.

Collar Yoke Force Management

Continuing to refer toFIG.4, zone123of the overlay120is referred to herein as a collar yoke adhesion zone123. In the aspects, the collar yoke adhesion zone123provides multiple benefits. Together with the collar yoke104, zone123provides supplemental force carrying ability among the eyelets106, the overlay rotation zone122and elastic zone121. Zone123also provides supplemental rigidity to collar yoke104to minimize slumping or buckling of the collar yoke's constituent parts under load. Zone123provides aesthetic differentiation and can be configured to enable a limited amount of elasticity and thereby offer an amount of energy storage and return.

Overlay Materials

Each of the zones of the elastomeric overlay120described above may be comprised of the same, different elastomeric constituents or constituents of varying composition. For example, the elastic zone121may have a softer durometer and increased stretch as compared to the collar yoke adhesion zone123. This can be accomplished by using a common substrate and varying the thickness, durometer, curing qualities, and other parameters as known in the art or by using a variety of different substrates in different locations of the same overlay120, such as thermoplastic rubber, thermoplastic urethane, silicones, and the like.

Eyestay109and Sidewall

FIG.2shows a view of the exterior surface of the shoe100with the elastomeric overlay120removed. An eye stay109is incorporated around the eyelets106, and then horizontally rearward under channel116(FIG.3) until it is locked, for example, with the heel counter panel110.

The eyestay109provides natural rigidity to shoe100. As forces from rotation zone122, inferior rotation anchor zone125, and channel116are passed into eyestay109, these forces can be spread across a greater area so that comfort can be maintained on the user and the longevity of shoe100can be maintained.

Forces into eyestay109from the rotation zone122, inferior rotation anchor zone125, and channel116during use are predominantly downward and forward and, as such, can be managed in multiple ways. Some of the force may travel down eyestay109into upper108and into sole101,102. Some of the force may be transmitted into the eyelets106and into laces105and into tongue107, especially below anterior gusset114. These forces are suspended along the top surface of the foot, travel through the foot and consequently into the midsole102and outsole101. A sidewall is generally considered a side panel of upper108. Sidewalls often hold aesthetic adornments such as shoe logos and may also be used to provide rigidity and structural stiffness to shoe100. Sidewalls may be reinforced by caging or tension bearing stitching138. Some of the force may travel through the rigidity of upper108and sidewall allowing compressive forces to reach the sole101,102without passing through the foot during locomotion.

Usage of stiff materials for upper108, sound stitching, inclusion of tension bearing stitching138elements between eyelets106and midsole102, or the usage of supplemental external materials to create a cage are mechanisms that may be applied to increase the structural strength and force carrying capacity of the sidewall of upper108. As such, applying these techniques will improve force transmission from the overlay rotation zone122and channel106through eyestay109, through heel counter panel110, and directly into upper108.

Upper108

FIG.3shows a view of the exterior surface of the shoe100with the elastomeric overlay120, eyestay109and heel counter panel110removed. These side and rear views allow a view of details of upper108, which in this aspect may be a continuous piece of sheet material that flows through the narrow channel116and into the collar yoke104.FIG.3may demonstrate that traditional shoe construction can be easily applied.

Stitching Overlap

FIG.2shows detail of eyestay stitching111and counter panel stitching112. In this aspect, narrow channel116(FIG.3) is further reinforced by intersection of stitching119that results in an “X” shaped stitching overlap113forming a point at the intersection. This “X” shaped stitching overlap113may be created by overlapping eyestay stitching111with counter panel stitching112, or may be created by independent stitching path construction where the stitching acts similarly to the cables of a suspension bridge. By locating the intersection of stitching overlap113in narrow channel116and overlay rotation zone122, strength against tension and shear are provided while still allowing a range of rotation motion during use.

A stitching overlap may be created with the intersection of tension-bearing stitching138used in some high performance athletic shoes.FIG.7Ais a representation of an application of tension-bearing stitching paths configured to maintain stability of shoe100, support upper108of shoe100from slumping below narrow channel116and provide an ability for narrow channel116to pivot while maintaining integrity. In this approach, four parallel rows of “S” (and reverse “S”) shaped tension-bearing stitching138paths are curved and overlap at a common “X” point113. A similar effect can be created with various other combinations of straight lines and curved lines intersecting at a desired point of rotation where the lines comprise stitching, tension-bearing stitching138, caging and the like.

Gathered Material in Channel116

The material used in construction of upper108may pass through narrow channel116in a flat manner. The material may also be gathered in a manner that creates at least one crease in the material that is generally oriented horizontal to the floor. Those familiar with fabrics will be familiar with the process of gathering. The stitching overlap113can then be applied over top of the gathered fabric. By gathering the fabric, the overlay rotation zone122is provided with additional range of rotation motion.

Many shoes are created with multiple layers of materials. In shoe100, some layers may pass through narrow channel116flat, while some layers may include gathering depending on the application of shoe100.

Supplemental Material in Channel116

To add further support and longevity in narrow channel116, additional materials may be integrated with the materials used for constructing upper108. For example, a small patch of fabric may reside between the outer surface material of upper108and the liner material. This additional material may include a variety of fabrics, for example, one way stretch fabric, two way stretch fabric, fabrics containing high strength materials such as para-aramid fibers, or other fabrics known in the art. The additional material may be bonded to upper108. The additional material may simply be integrated into upper108by virtue of attachment through stitching overlap113. The additional material may lay flat or be gathered in narrow channel116. The overlay may also be supported in rotation zone122in other ways, for example, encircling the narrow channel116and overlay material of the rotation zone122with material (for example, multiple wraps of thread, ribbon, elastomeric material, as one might wrap an eyelet to a fishing rod).

Supplemental Stiffeners

FIGS.6and7show supplemental stiffeners. The use of supplemental stiffening is common in sneaker construction. The technique may be applied, for example, in the creation of heel counter130. The use of supplemental stiffeners can be implemented in various ways. Following traditional design of heel counters130, stiffeners made of plastic sheet are sandwiched between a sock liner and padding system137and upper108. Force may be transferred to a supplemental stiffener indirectly through a layer of upper108or sock liner and padding system137during use. It may also be transferred into and out of a supplemental stiffener by providing direct fastening between elements of an elastomeric overlay120and supplemental stiffener.

Tension, torque, compression, shear and other forces across a collar yoke104can distort the collar yoke104during use. While a collar yoke104made from multiple layers of sturdy sheet materials such as leather or similar materials may be able to withstand slumping or bending without reinforcement, many shoe designs do not have such stiff materials and are likely to bend, slump or otherwise deform under pressure. This deformation may prevent the range of motion found in a particular application to become usable. Therefore, shoes without sufficient strength in upper materials may require reinforcement in order to maintain their shape and longevity. The nature, required rigidity, required materials and require design are based upon the spring rates and forces designed into the footwear system of the first aspect. A collar yoke stiffener131(FIG.6) may be responsible for assisting proper force transfer within and across collar yoke104while also protecting collar yoke104from slumping, buckling or otherwise losing its intended and comfortable shape.

Referring now toFIG.8, shoe100is shown to have multiple forces acting upon it during locomotion. The forces shown in this drawing comprise primary forces associated with the energy management of shoe100. Other forces associated with routine use of shoe100are acknowledged but not shown here to help ensure clarity. These primary energy management forces include a spring force, a shin force and a force exerted on the pivot point (the vicinity of channel116). Shin force is a force associated with the front face of the lower leg118. Spring force is a force generally parallel to the Achilles tendon associated with the elastic zone121and elastomeric overlay120. The force exerted on the pivot point is associated with the forces through narrow channel116and overlay rotation zone122. Hypothetical dimensions of collar yoke104are shown inFIG.8to be a moment arm of 5 cm between the pivot point and the shin force, and 8 cm between the pivot point and the spring force. A spring rate in the elastic zone121of 25 Newton/cm can lead to a spring force of 50 Newton as a result of a 2 cm stretch of elastic zone121while the ankle is near maximum dorsiflexion. A 50 Newton force assuming a moment arm of 8 cm leads to a torque of 400 Newton-cm on the collar yoke104. Knowing that there is a lateral and medial side of the collar yoke104, and assuming a moment arm of 5 cm to the eyelets106, there is an approximate force of 40 Newton to the lateral eyelets106and 40 Newton to the medial eyelets106, resulting in a collective shin force of 80 Newton. There is also a force upon the pivot point of 103 Newton that is oriented down and forward, nominally along eyestay109. The geometry of such a system also enables it to transform some of the work into electrical current which can be stored or used as it is generated. For example, an elastic member may include a coaxial device that enables generation of electric current as the elastic element is stretched and or released. A variety of small power harvesting mechanisms may be employed, examples comprise but are not limited to solenoids, coils, piezoelectrics, micro-electric generator systems, reciprocating members to drive alternators, and the like.

Since the collar yoke104can be subject to significant forces, including a collar yoke stiffener131can help better manage those forces. An eyestay and collar stiffener133can help manage forces transmitted through channel116and overlay rotation zone122. As forces increase, there is a tendency for upper108to slump or buckle. The eyestay and collar stiffener133can support eyestay109, collar yoke104and upper108of shoe100from slumping or bending under the force received from the collar yoke104. The size and shape of the eyestay and collar stiffener133can vary in accordance with the amount of force anticipated. While some of the downward force in collar yoke104will be transmitted into the malleolus bulges, much of the force from collar yoke104is transmitted down and forward, into upper108in alignment with the long axis of eyestay109. Eyestay109and eyestay and collar stiffener133may be designed to pass multiple eyelets106to help ensure that forces are distributed and do not localize in one vulnerable spot. Such stiffeners may be optimized to meet shoe application requirements. As an exampleFIG.7Bshows a variation of eyestay and collar stiffener140.

The inferior eyestay and collar stiffener133can be fastened by a number of means including adhesives, stitching, grommeting of eyelets106, anchoring to sidewall cage materials, anchoring to the midsole102, and other means known in the art.

An upper stiffener135can help manage forces transmitted through channel116and rotation zone122. As forces increase, there is a tendency for upper108to slump or buckle. Upper stiffener135can support the eyestay and collar stiffener134. It can also transmit forces directly to midsole102, reducing the amount of force distributed on the foot. The size and shape of upper stiffener135can vary in accordance with the amount of force anticipated. Upper stiffener135is shown adjacent but not connected to eyestay and collar stiffener134. These two components may be integrated as one singular piece of material or may reside adjacent to each other. Upper stiffener135may further be integrated as one singular piece with the heel counter. Upper stiffener135can be further strengthened by integration with cage materials over the sidewall integration with tension bearing stitching138elements which connect eyelets106to midsole102.

Supplemental Stiffener Interface Area

Referring again toFIG.6, eyestay and collar stiffener133has a radiused receiving area134. Collar yoke stiffener131has a radiused protrusion132that sits proximal to the eyestay and collar stiffener's radiused receiving area134. Protrustion132has a smaller radius than the receiving area134. By fastening eyestay and collar stiffener133and collar yoke stiffener131to the exterior shoe surface or to elastomeric overlay120, a rotating joint is created that facilitates rotation. Orienting the radius of the eyestay and collar stiffener's radiused receiving area134towards the rear, the radius acts as a cup device that anticipates the forward and downward forces that are transmitted from the collar yoke104and the collar yoke stiffener131. The differential in radius allows for a small amount of fore and aft laxity to reflect glide of the talus on the ankle mortice with ankle flexion and extension.

Supplemental Stiffener Alternatives

The term “supplemental stiffener” is used to generically refer to a stiffener constructed from any number of materials or combination of materials that can be employed according to the needs of each application. The common use of plastic sheet in heel counters of athletic shoes makes plastic sheet one choice for this application. Supplemental stiffening may also be achieved by judicious choice of leathers and other upper materials in layers and or laminates in areas of support.

That said, a wide variety of other materials can also be used. For example, use of carbon fiber and fiberglass components may be applied in many higher performance athletic shoes. A benefit of carbon fiber is its ability to be contoured in three dimensions with singular or multiple curves, including complex saddle shapes, while maintaining light weight and strength. Very high performance applications may require carbon fiber to enable high spring rates and energy storage and return capabilities. Metals and alloys can be used in sheet format, castings or other forms for certain applications, and may be used in toe box protection and shank creation. The use of laminated or corrugated sheets can also improve the structural qualities of the stiffeners. Use of higher forces and higher strength supplemental stiffeners may require stronger joint construction at their pivot interface proximal to narrow channel116. A variety of hinge types may be used for a high strength pivot interface, including ball joints, pin hinges where the pin is either made of a high strength material or a shoe lace or other means known in the art.

Additionally, the use of tension bearing stitching138or fibers to manage tensile forces between the eyestay and sole or heel counter establishes excellent opportunity for improving upper rigidity. The use of suspension bridge-like geometries creates stability in sidewalls. Similar tensile patterns can be established circumferentially to further boost stiffness.

Additionally, the sides of collar yoke104may be constructed with horizontally oriented corrugated or hollow elements that resist bending near the Achilles, but enable flex and bending above the malleolus bulge. This further enables an oval shape of collar yoke104to apply force to the sides of the lower leg118without overly constricting the back of the lower leg.

Adhesive Application

FIG.5focuses on adhesive application and bonding to the substrate. The use of adhesives is well known for fastening in the footwear industry. Bonding of elastomeric overlay120to the surface below can be optimized. By eliminating the use of adhesives in close proximity to either end of elastic zone121or small areas within the rotation zone122, one can reduce the likelihood of overly high pressure points and extend the working range of motion and longevity of the elastomeric overlay120. A diagram of zones that can be kept free of adhesives is shown inFIG.5and is labeled by grey zones128.

Spring Rate Versus Cross Sectional Area

Assuming a consistent material selection and preparation across elastic zone121(FIG.4) of elastomeric overlay120(FIG.1), the spring rate of elastic zone121is correlated against the cross sectional area of the molded elastic member within the zone. Narrowing of the elastic zone121as viewed from the rear will reduce the cross-sectional area, assuming a constant thickness. This may be a problem in the event that a designer wishes to use an hourglass type of shape from the rear view. The starting spring rate of elastic zone121is predicated upon the narrowest cross sectional area. As such, it may be necessary to increase the thickness of elastic zone121to compensate for narrowing of elastic zone121. Providing a longer volume with a consistent cross sectional area provides a more uniform spring rate and lower likelihood of undue fatigue in a small volume that could shorten the life of a product.

Lacing105

As currently taught, the user tightens laces105of shoe100in the same way as is done with other high top athletic shoes. Laces105are oriented as shown in lace routing136such that they travel from eyestay109below anterior gusset114back to a loop in proximity to narrow channel116prior to moving up to eyelets106in collar yoke104. In this way, rotation of collar yoke104will not place unnecessary forces that may loosen or tighten laces105during use.

A user of shoe100has an option to point their toes while tightening their shoelaces105to reduce tension in the elastic zone121, but this is not a requirement. The user ties shoe100to the desired collar tightness, just as one would do with a conventional high top shoe. When shoe100is adequately tightened, shoe100may operate its force management features (for example,FIG.8). When shoe100is worn slack and untied, the force management features are inactive. The user has an option to somewhat reduce the amount of engagement of the force management feature by intentionally keeping the collar yoke104loosely tied, thereby limiting the amount of range of motion that can be engaged. An elongated geometry of collar yoke104, as mentioned earlier, restricts the amount of collar force applied to the rear face of lower leg118, even when the user tightens the collar yoke104fully.

User Adjustment of Spring Rate

Some users of shoe100may wish to have ability to adjust the spring rate of their shoes in excess of the spring rate of elastic zone121of overlay120. There are several ways that can be implemented, including the following four ways.

First, providing at least one supplemental elastic member that is integrated to the back of the heel counter region. The elastic member may be anchored near the interface to midsole102and have a neutral length short of the heel counter height. When not in use, the elastic member may reside external to shoe100or in a pocketed area. The user then has an option of pulling the top end of the elastic member and engaging it into a fastening device above posterior gusset115. For example a small gage elastic cord may be utilized as the elastic member. It may be anchored at midsole102on its bottom end, and its top end may have a small hook affixed. When not in use, the small hook is visible above the heel counter, and when in use, the small hook could engage with a receptacle above posterior gusset115, thereby increasing the spring rate. The user could then adjust the supplemental elastic member(s) to match their desired level of force management for the activity in which they plan to engage. Any variety of anchoring systems can be employed. Shoe100may be constructed with a pull tab above the heel counter that extends back behind the limits of shoe100. Having the supplemental elastic member and anchoring devices visible at the back of shoe100would have a similar aesthetic impact as a rear pull tab.

Second, coaxial elastic materials through the elastic zone. Similar to variation1in the paragraph above, the supplemental elastic member may be anchored along the sides of the collar yoke104. By creating at least one hollow opening through elastic zone121, an additional pair of elastic members can be oriented through elastic zone121. Supplemental elastic members can be anchored at the base of the heel counter away from contact with the skin. They can then traverse past the heel counter and up through a hollow core of the elastic zone121. They can then branch to the left and right sides of collar yoke104where they can be made tight or loose by the user. Adjustable anchoring can be accomplished by a variety of means, including lacing and ties, straps with hook and loop fasteners, etc.

Third, altering the active spring geometry. Elastic zone121can be altered by restricting its motion through a supplemental device. If elastic zone121has a slice down its midline as viewed from the rear, a physical element may be inserted that displaces the sides of the split elastic member outward, thus consuming some of the spring length and providing engagement of the elastic member at an earlier point of ankle rotation.

Fourth, supplemental elastic sheet material. The exposed area of the posterior gusset may be covered by an elastic sheet material. Any number of materials could be selected, including elastic wovens, non worvens, elastomeric sheet materials, etc. The shoe could be supplied with a variety of posterior gusset covers, each with a different spring rate to supplement the spring rate of the elastic zone121. Posterior gusset covers would need to be anchored above and below the gusset in order to transfer and manage forces.

Thus, through a footwear system of the first aspect, elastic mechanisms may be integrated into footwear which may assist user locomotion selectably by the user's either lacing the collar yoke104more tightly or loosely. Under flexion or dorsiflexion, pressure is applied from lower leg118into tongue107and from tongue107into laces105. Laces105transfer forces into eyelets106, and eyelets106transfer forces into a combination of the collar yoke104, optional collar yoke stiffener131, and overlay120(in the collar yoke adhesion zone123). These components collectively manage torsional forces with narrow channel116and rotation zone122providing a fulcrum (through the superior rotation anchor zone124) and then apply force into elastic zone121(through the superior elastic anchor zone) during use. Elastic zone121applies force into (through the inferior elastic anchor zone127) the heel counter panel of the shoe110. This force is then translated from the heel counter panel110area of the shoe into the foot.

As the user increases flexion and dorsiflexion, elastic zone121absorbs force and stores it as potential energy. This externalization of force reduces the amount of force that needs to be managed by the Achilles tendon, calf muscles and various other muscles & tendons and so elastic zone121assists a user's Achilles tendon. This reduction in force conserves energy of the user and can reduce fatigue.

As the user continues in their stride and starts to extend and plantar flex, the potential energy in elastic zone121is released and forces are exerted into the leg118and foot. This results in a locomotion system inducing the foot to extend and plantar flex, providing a harmonized return of energy at the same time the body requires energy to propel their gait. This application of force over time and distance results in work produced by the footwear energy management system. The work produced by the system can benefit the user by supplementing the output of work by the users' tendons and muscles thereby improving performance and enabling faster locomotion or higher jumping; or the work produced by the system can displace work required by the user's tendons and muscles thereby reducing the consumption of oxygen by the muscles and reducing the tendency toward fatigue.

Spring Location

Location of a tension spring within this aspect is within the elastic zone121of the overlay120. Spring force may be designed into additional areas in other variations of this first aspect. For example, the attachment of eyelets106to collar yoke104may include an elastic component.

Application to Boots and Footwear for Other Vocations and Athletic Endeavors

The above description may be applied, for example, in design of high-top style athletic shoes. The same approach may also be employed within other footwear—such as hiking boots, work boots, military boots, cleated shoes, and so on which may be modified to incorporate the structural elements of the first aspect. A wide variety of sports may benefit from integration of such a system into their specific footwear, basketball players benefit from higher jumping and improved endurance & speed, volleyball players benefit from higher jumping and further distance in leaping reaches, baseball players benefit from higher top sprinting speeds, football players benefit from offsetting some loading on their Achilles during blocking, soccer and rugby players benefit from improved stamina and speed, runners and joggers benefit from reduced load on Achilles and improved endurance and speed over flat and hilly terrain, walkers benefit from improved endurance and easier hill climbing, hikers benefit from improved heel lock-down and lower likelihood of heel blistering while also enjoying improved endurance and the dynamic offset of pack weight, general footwear wearers enjoy the benefits of new and exciting aesthetic differentiation and styling made possible by the system. All of these individuals may benefit from the protective benefits conferred by the system as well. The integrated endoskeleton, together with the integrated tension spring confer similar if not superior benefits to a separate hinged ankle brace in service of reducing forces that conduce towards inversion and eversion injuries. The externalization of forces also relieves pressure from the long arches of the foot, reducing the stresses that conduce towards plantar fasciitis and other sources of foot pain.

Aspect 2

Table of Reference Numerals:

Second aspect of a shoe200outsole201elastic member202interface between elastic member and outsole203rotatable collar yoke204rotation zone205interface between elastic member and collar yoke206alternative routing of elastic member207shaped elastic member208heel counter209posterior gusset210upper211liner212eyelet213

FIG.9shows various side views (FIGS.9A,9C and9D) and a rear view (FIG.9B) of another aspect of a shoe200incorporating many of the structural elements of first aspect shoe100. Shoe200functions similarly to the initial aspect, but highlights different ways in which to create and anchor an elastic zone as well as different ways to create a rotation zone. This aspect creates elastic tension through the use of an elastic member in lieu of an elastic zone within an elastomeric overlay as shown in the first aspect (FIGS.1-8).

FIG.9shows three different approaches to the creation of an elastic member.FIG.9Ashows an external side view of the aspect andFIG.9Bshows an external rear view of the aspect.FIG.9Cshows a cutaway view of the same aspect to reveal construction layers, with a different approach to the shape and anchoring of the elastic member.FIG.9Dshows a different approach to the shaping, placement and anchoring of the elastic member.

An elastic member202running parallel to an Achilles tendon during use provides the force carrying capability between a collar yoke204and the heel area of shoe200. In this configuration, the elastic member202is anchored at its base by becoming integral with shoe outsole201at an interface point203. Modern athletic shoe construction often relies upon a variety of materials and colors in the construction of an outsole201. Interface point203enables a continuous mold to service the outsole201and elastic member202.

The elastic member202may have different material and performance properties than the material in outsole201, allowing the elastic member to have higher qualities of elasticity with reduced elastomeric loss, while outsole201may have higher scuff resistance and wear properties.

Elastic member202is anchored at its top by splitting into a “Y” shape and fastening to both sides of collar yoke204. Collar yoke204may include a supplemental stiffener element or it may rely upon a single or multiple layer construction of upper material to enable it to properly manage forces between the leg, rotation zone205(FIG.9A) and elastic member202. If a supplemental stiffener element is used, elastic member202may be anchored directly into the supplemental stiffener element. Elastic member202may also be anchored at the top by an adjustable feature, such as a link to a hook and loop strap system (not shown) that provided a fastener with adjustable length, or a series of hooks which can provide variable spring lengths.

FIG.9Cshows another approach to an elastic member207. In this instance, the elastic member207is anchored at its top at one of the eyelets213, for example, a top-most eyelet of collar yoke204. The elastic member is supported through collar yoke204. Elastic member207is anchored at its base, for example, by attaching to an internal heel counter212.

FIG.9Dshows another approach to an elastic member208. In this instance, elastic member208is formed in a visually appealing shape. For example, elastic member208may be formed with shaped elastomeric material to create the letters R-O-C-K. This is one example of a visually appealing shape, and many other shapes may be employed. This is one example of the use of elastomeric material. Other spring materials may be employed—such as woven and nonwoven fabrics, sheet rubber, silicones, or other materials known in the art. Sheet materials such as latex may be employed where an appealing graphic is printed on the latex and the graphic changes its appearance upon stretch of the latex sheet during the opening of posterior gusset210.

The various approaches in the design of the elastic members202,207and208, the superior anchor points and inferior anchor points may be arranged in a variety of combinations and still be novel. These approaches may also be employed with elements of the elastomeric overlay as shown in the prior aspect to create novel aesthetic and functional solutions.

Each of the designs inFIGS.9A,9B,9C and9Dutilize a rotation zone205. In this aspect, rotation zone205may be created from a flexible material that is bonded to the upper material above and below rotation zone205. Flexible materials may include woven and non-woven fabrics, vinyls, rubbers, urethanes, silicones, and such materials known in the art. The materials may be single layered or a composite of multiple materials in multiple layers.

Any need for supplemental reinforcement of the areas above and below rotation zone205will depend upon the nature of the materials selected for upper211as well as the desired spring force of elastic member202. If upper materials do not have sufficient rigidity to accommodate the spring forces during use, supplemental reinforcement may be introduced as described in the first aspect.

Aspect 3

Diagonal Tension Spring to Sliding Yoke

Table of Reference Numerals

third aspect of a shoe300heel counter panel301tension spring302collar303top collar yoke lobe304eyelets305D-ring306curved D ring307pivot point308anchor stitching310leg311passageway312inlet to passageway313tongue315laces316sliding surface317semi-rigid member318upper319foot320

FIG.10shows several views of a third aspect of a shoe which practices an energy management system similarly to the first aspect, shoe300.FIGS.10A and10Bshow external side and rear views, respectively.FIG.10Cshows an internal view of shoe300, whileFIGS.10D and10Eshow additional variations of the third aspect.

FIG.10includes drawings of a modified high top athletic shoe300, with a diagonal tension spring302at the top of shoe300. Tension spring302may have an inferior anchor above a heel counter310and a superior anchor at a high top collar yoke lobe304. The shoe300includes an upper319and a collar assembly303that is the above the upper319.

Upper Anchor Variations

Without specific drawing references, force from a leg311is transferred into a tongue, into laces, into eyelets, into a yoke, into a tension spring, into the rear of the shoe above the heel counter during locomotion.

Tension spring302may be anchored to the high top collar yoke lobe304through a variety of means.FIG.100shows the top collar yoke lobe304as a multiple ply construction of vinyl, fabric, leather or other material common in shoe making. In this aspect, tension spring302is sandwiched between the plies of the material used to construct the top collar yoke lobe304and anchored by connection to eyelets305.

FIG.10Dshows tension spring302coupled to an off-set D-Ring306. Laces,316are also connected through the off-set D-Ring306. D-Ring306acts in lieu of the top collar yoke lobe304.

FIG.10Eshows tension spring302attached to a curved D-Ring307which can be attached to a top collar yoke lobe304. Curved D-Ring307is fastened rotatably through a pivot point308to the top collar yoke lobe304. The pivot point308allows the top collar yoke lobe304to rotate relative to the spring and allow laces316to lay flat against the user's leg311.

In each of the configurations ofFIG.10, force is applied to and from the lower front face of leg311, into a tongue315, into laces316, into eyelets305, into the top collar yoke lobe304or D-Ring306, into tension spring302, into the rear of shoe300above the heel counter during locomotion.

Flexibility in shoe300to allow forward rotation of the leg311is enabled by separation of the of the top collar yoke lobe304away from the rest of the collar303. This allows range of motion of the lobe to follow the leg311as it moves forward in flexion towards dorsiflexion and back in extension towards plantar flexion. The tension spring302has primary force direction in linear tension, but also can resist shear and rotation.

Tension spring302is anchored, for example, to the top of the heel counter panel301through stitching310, adhesive or other common means in proximity to the top of the heel counter301. In this manner, force from the tension spring302is transferred into the shoe300during locomotion. Shoe300thereby may transfer force into a users' foot320.

Construction

Tension spring302passes through a passageway312created in the collar303. The passageway312for spring302is created to allow tension spring302to stretch linearly (direction arrow) with minimal resistance, but provides support to assist tension spring302from being pulled or slumping in the downward direction during motion of leg311. This resistance in the downward direction helps prevent high top collar yoke lobe304from excessively slumping down the user's leg311in dorsiflexion or plantar flexion. The energy management system of shoe300can be further supported against slump by use of a semi-rigid member318that can add supplemental rigidity to tension spring302while inside passageway312and act as a cantilever to prevent downward slump of top collar yoke lobe304. Semi-rigid member318can be fastened to tension spring302or attached to high top collar yoke lobe304.

Lacing Detail

When the laces316are loose, the top collar yoke lobe304is pulled by tension in tension spring302to a resting spot against the vertical front face of the collar303. The shoe300therefore can maintain the appearance of current high top athletic shoe designs. To tighten the shoe300, the user may position his or her foot in the plantar flexed position (tip toe) and tighten the shoe as one would any other high top shoe. Upon returning to an upright stance, the tension spring302stretches to reflect the increase in distance between top collar yoke lobe304and top of the heel counter310.

Locomotion of Shoe300

In the gait cycle, the length of tension spring302expands during flexion/dorsiflexion and contracts during extension/plantar flexion. In this manner, tension spring302is able to contribute to energy management, for example, in a similar manner as the aspects described above. Dorsiflexion in the ankle leads to forward motion of leg311relative to the back of the foot320, which applies force on tongue315, which applies force on laces316, which apply force on top collar yoke lobe304, which applies a diagonal force (directional arrow) on tension spring302which manages the energy and applies force on the inferior anchor310above the heal counter panel301, which is part of shoe300, which imparts upward force on the heel of foot320. The end result is that the forces extend the foot toward plantar flexion.

Tension spring302exerts force against dorsiflexion thereby saving muscle exertion in the early phase of the gait cycle. The result of applying force over distance is that the work results in elastic potential energy being stored in tension spring302. Later in the gait cycle as the ankle starts to extend toward plantar flexion, tension spring302then exerts force to support plantar flexion thereby saving muscle exertion in that phase of the gait cycle.

Depending upon the activity, such an energy management system can create a range of motion of 2.5 cm or more across primary tension spring401. Referring now toFIG.13, primary forces associated with diagonal tension spring aspects are described. Aspect shoe300and aspect shoe400are both shown for clarity, and represent similar force arrangements. Other forces associated with gait and athletic usage are acknowledged but not shown to help ensure clarity of the drawing. Five forces are shown, spring force, shin force, slump force, horizontal extension force, and vertical extension force. Spring force is associated with a tension spring, for example, spring302. Shin force is associated with the front face of the lower leg and passes through a tongue, for example, tongue315prior to being transferred to other components. Slump force is associated with a tendency for the top collar yoke lobe304, for example, lobe304to slide down the front face of the leg. Horizontal extension force is associated with an area above the top of the heel counter panel301and drives shoe300,400forward relative to the foot. Vertical extension force is associated with an area above the top of the heel counter panel301and lifts shoe300,400up relative to the foot. The horizontal and vertical extension forces work to keep shoe300,400in close contact with the foot, and also help drive plantar flexion motion. Assuming that the lateral and medial tension springs302have a collective spring rate of 20 Newton/cm, an increase in length of 2.5 cm could provide 50 Newton of force at full extension. As this force is anchored near the top of the heel counter panel301, the force creates the equivalent of approximately 35 Newton in the lifting direction and 35 Newton in the forward direction. This diagonal direction of the linear force upon the top of the heel counter panel301area aids in lifting the heel of the shoe300toward the heel of the user, improving comfort and security of the shoe300against the foot while also driving plantar flexion motion.

Range of motion of top collar yoke lobe304is dependent upon maintaining position on the lower leg311and prevention of slumping down the leg. Provision of a surface for allowing top collar yoke lobe304to slide fore and aft in alignment with tension spring302without slumping down can be accomplished in many ways. For example, use of a sliding surface317(FIG.10A). This sliding surface317allows fore and aft motion of top collar yoke lobe304while resisting downward motion by top collar yoke lobe304.

User Adjustment of Spring Tension

This third aspect could be modified to also include adjustment features that enable a user to adjust the spring rate and laxity in shoe300. For example, tension spring302shown inFIG.10can be passed through a length adjustment feature as may be known from the art of fabric webbing and straps found on backpacks and such. Tension spring302could also be adjusted by passing through a D-Ring306as shown inFIGS.10D and10Eand then anchoring with a hook and loop anchor system as is common in footwear design. This would enable a user to adjust the initial spring laxity or tightness, thereby adjusting spring rate and complexion to meet their immediate needs.

Aspect 4

Diagonal Tension Spring to Hinged Yoke with Fore/Aft Laxity

Table of Reference Numerals:

Fourth shoe aspect400primary tension spring401supplemental tension spring402inferior anchor403heel counter404heel counter panel405collar of the shoe406eyelet407anterior gusset408posterior gusset409top collar yoke lobe410narrow channel of material412laces414flexible sock liner415tongue416stitching417eyestay418upper420

FIG.11shows a fourth shoe aspect having an energy management system similar to that of the first aspect which will be further discussed with reference toFIG.13, a shoe400having a diagonal tension spring system401,402.FIG.11Ashows an external side view whileFIG.11Bshows a rear view of the same aspect.FIG.11Cshows a side view of a partial cutaway of the same aspect while11D shows the rear view of the same shoe400.

FIGS.11A,11B,11C and11Dare drawings, for example, of a modified high top athletic shoe400, with a shaped anterior gusset408and a posterior gusset409which divide the upper420such that a narrow channel of material412remains thereby creating a top collar yoke lobe410section of upper420. Top collar yoke lobe410is capable of motion during use and is also connected to a collar406by at least one tension spring401,402oriented diagonally. A diagonal tension spring system may include at least one of a primary tension spring401(FIGS.11A and11B) and supplemental tension spring402(FIGS.11C and11D). So spring401overlays spring402. The primary tension spring401is made out of sheet material and has an inferior anchor along a collar of the shoe406and a superior anchor along the boundary surface of the high top collar yoke lobe410with the posterior gusset409. The secondary tension spring402has an inferior anchor403above the top of a heel counter404and a superior anchor at a high top collar yoke lobe410by connection to eyelets407. Inferior anchors can be fastened through any common means. Anchors may affix to internal layers such as flexible liner material415, layered materials used in construction or outer surfaces such as upper420.

Flexibility in the shoe400to allow forward rotation of the leg is enabled by distinction of the of the top collar yoke lobe410as a movable entity relative to the rest of the collar406by means of a shaped forward gusset408and a posterior gusset409. The positioning of said gussets results in a narrow channel of material412that enables rotation in the top collar yoke lobe410as well as fore and aft laxity of motion. The tension springs401and402have primary force direction in linear tension and can manage forces between the top collar yoke lobe410and collar406.

Lacing and Appearance

When the laces414are loose during use, top collar yoke lobe410is pulled by tension in tension springs401and402to a resting spot dictated by the pre-tensioning of springs401,402. Shoe400therefore does not suffer from negative aesthetic impact of appendages or ancillary equipment. Shoe400can thereby maintain appearance qualities similar to other high top athletic shoes and offer an opportunity for delivering appealing ornamental designs that engage and interest buyers.

To tighten shoe400, the user may position his or her foot in the plantar flexed position (tip toe) and tighten shoe400as one would any other high top shoe. Upon returning to an upright stance, tension springs401and402stretch to reflect the increase in distance between top collar yoke lobe410and top of the inferior anchor403and collar406.

Foam padding is commonly used in the construction of athletic shoes. It is assumed that a shoe designer would select an appropriate grade of foam padding to employ within the posterior gusset409space to maintain the appropriate comfort to the user. Padding would need to be able to compress and stretch across its planar dimensions to accommodate range of motion in the posterior gusset409. This range of motion can be further accommodated by incisions across the foam surface to enable further stretch.

Function

In the gait cycle, the lengths of tension springs401and402expand during dorsiflexion motion and contract during plantar flexion motion. In this manner, tension springs401and402are able to contribute to an energy management of shoe400. The tension springs401and402exert force against dorsiflexion thereby saving muscle exertion in the early phase of the gait cycle. The result of applying force over distance is that the work results in elastic potential energy being stored in tension springs401and402. Later in the gait cycle as the ankle starts to extend towards plantar flexion, springs401,402then exert force to support plantar flexion thereby saving muscle exertion in that phase of the gait cycle.

Dorsiflexion motion in the ankle leads to forward motion of the leg411relative to the ankle which applies force on the tongue416, which applies force on the laces414, which apply force on the top collar yoke lobe410, which applies diagonal force on springs401and402, which manage the energy and apply force on the inferior anchor403above the heel counter404; thereby imparting an upward force on the heel of foot.

Depending upon the activity, such an energy management system can create a nominal range of motion of 2.5 cm or more across primary tension spring401. Assuming that primary tension spring401has a spring rate of 20 Newtons/cm, an increase in length of 2.5 cm could provide 50 Newton of force at full extension. Assuming that the supplemental tension spring402has a spring rate of 10 Newtons/cm, an increase in length of 2.0 cm could provide an additional force of 20 Newton at full extension. The diagonal direction of the linear forces aids in lifting the heel of shoe400toward the heel of the user, improving comfort and security.

The resting length and spring rate of the two springs401and402can be tuned to provide non-tension spring rates that are advantageous to athletic activity. For example, the supplemental tension spring402could have a spring rate of 30 Newtons/cm, but have 1 cm of laxity prior to engagement. This would yield no increased spring force until more than 1 cm of bottom spring extension. At full extension of 2.0 cm, the spring would then provide an additional 30 N of force.

Reinforcement

Range of motion of the top collar yoke lobe410is dependent upon maintaining position on the lower leg and prevention of slumping down the leg. Stitching417is shown as one means of increasing the rigidity of an internal or external eyestay418. Eyestay418is shown traversing to the midsole as a means to help resist downward motion along the top of the foot surface or slumping. In this fourth aspect, stitching417can improve the resilience and viability of the shoe's construction material—such as vinyl, fabric, leather, and the like. The stitching417can also be crossed, as shown, in an “X” shaped pattern in the area of narrow channel412. The “X” shaped pattern allows for rotation across narrow channel412while minimizing deformation and wear from shear, tension or compression. Eyestay418may also be made more rigid by the addition of supplemental materials or stiffeners.

Forward Gusset Shape

The anterior gusset408has an upward facing component at an end pointing toward top collar yoke lobe410. The boundaries of the anterior gusset408are created by the convergence of an outer radius emanating from a continuation of the gusset's lower edge which meets an inner radius emanating from a continuation of the gusset's upper edge. Such an upward facing removal of material is designed to facilitate a small amount of forward laxity of the top collar yoke lobe410. While a straight-walled anterior gusset408with no upturn may enable rotation across narrow channel412, such an anterior gusset may resist fore and aft motion of top collar yoke lobe410. Shaping of anterior gusset408with an upward facing component provides laxity to enable a small amount of fore and aft motion of top collar yoke lobe410to follow the fore and aft range of motion of the leg associated with slide laxity in the ankle joint while minimizing resistance and extending the longevity of the narrow channel412.

Aspect 5

Diagonal Tension and Stay System

Table of Reference Numerals:

Fifth shoe aspect500bi-directional springs502inferior anchors along the bottom collar504superior anchors along the top collar505rotatable stays506bottom collar509top collar yoke510leg511bootie512strap closure515floating bootie514

FIG.12shows a fifth shoe aspect, shoe500.FIG.12Ashows an external side view whileFIG.12Bshows a rear view of shoe500.FIG.12Cshows a partial cutaway view of shoe500as doesFIG.12Dwhich also includes a view of a user's leg511and the user's foot in a tight fitting bootie512of shoe500.

FIGS.12A,12B,12C and12Dare drawings of a modified high top athletic shoe500, with bi-directional springs502. One example of bi-directional springs is elastomeric sheet which offers spring force in both horizontal and vertical planes. Springs502have an inferior anchor along the bottom collar504and a superior anchor along the top collar505.

Flexibility in shoe500to allow forward rotation of the leg511is enabled by separation of the top collar yoke510away from bottom collar509by means of rotatable stays506. By rotatable stays is intended the ability to assist rotation of the leg511during locomotion. Rotatable stays506have inferior anchors along the bottom collar504and superior anchors along the top collar505. Rotatable stays506may be fastened to their anchor points in a variety of ways, such as stitching or through resting in a sewn pocket, or other means. Rotatable stays506may be integral with the springs502or may be positioned adjacent.

In the gait cycle, the position of top collar yoke510relative to bottom collar509moves forward in dorsiflexion and rearward in plantar flexion. Biasing the geometric resting angle of the rotatable stays506, one can create a vertical motion relative to the horizontal motion. By rotatable, it is intended that each rotatable stay506creates a three bar linkage, where the top collar yoke510represents one bar, the rotatable stays506represent one bar and the bottom collar509represent one bar. During the gait cycle, the top collar yoke510moves fore and aft relative to the bottom collar509. This fore and aft motion results in a change in rotation angle of the stay relative to the top collar yoke510and bottom collar509. Using geometric principles, one can establish a starting angle and length of the rotatable stays506and thereby create a motion tangential to the fore aft motion which can either create more or less distance between the top collar yoke510and bottom collar509.

When rotatable stays506are oriented in a forward-canted angle at rest, as shown inFIG.12C, forward motion of the top collar yoke510results in a reduction in gap between the top collar yoke510and bottom collar509. This reduction in distance between collars pulls the heel of shoe500up relative to the top collar yoke510as it moves forward during dorsiflexion. By having the top collar yoke510place downward force on the front of leg511as well as the sides of the lower leg511through the malleolus ankle bulge, the energy management system of shoe500can place an equal and opposite lifting force on the bottom rear of the foot to drive the user towards plantar flexion.

Depending upon the activity, such a system can create a forward range of motion of 2 cm or more in top collar yoke510relative to bottom collar509, and a vertical range of motion of 0.4 cm or more in the gap between top collar yoke510relative to bottom collar509.

The aspect inFIG.12also may include an internal slipper-type of liner known in the industry as a bootie512. Booties are alternative means of providing comfortable liners. In shoe500, the heel area of bootie512may be connected to top collar yoke510.

When stays506are oriented in a rearward canted angle at rest, as shown inFIG.12D, forward motion of top collar yoke510results in an increase in gap between the top collar yoke510and bottom collar509. This increase in distance between collars pulls the heel of bootie512up relative to shoe500during dorsiflexion. By having top collar yoke510place upward force on the foot through the bootie512, the system can place an equal and opposite lifting force on the bottom rear of the foot to drive the user towards plantar flexion.

Depending upon the activity, such a system can create a forward range of motion of 2 cm or more in the top collar yoke510relative to the bottom collar509, and a vertical range of motion of 0.3 cm or more in lifting the bootie512.

Aspect 6

Open Yoke Vertical Spring Sandal

Table of Reference Numerals:

Sixth aspect—shoe600in the form of a sandaloutsole601footbed602elastic member603inferior elastic anchor604superior elastic anchor605forward strap stanchion606aft strap stanchion607foot strap608front ankle strap609rear ankle strap610yoke side611yoke pivot612leg strap pivot613leg strap614aft strap stanchion stiffeners615yoke stiffeners616

FIG.14shows an external side view of sixth aspect, sandal600.FIG.14is a drawing of a modified sandal600, with an open yoke system that transfers force from a leg over a pivot to a spring.

The foot is held to the sandal600by way of sandal straps, which include a foot strap608, front ankle strap609and rear ankle strap610. The foot strap608is anchored to the sandal600by a forward strap stanchion606. Ankle straps609,610are anchored to shoe600by an aft strap stanchion607. The configuration of straps described here is only one of many configurations possible in sandal design. People with knowledge of the art may configure other strap systems for the traditional elements of the sandal in ways that fit their application.

Force is received from the lower leg into a leg strap614. The leg strap614is an element of a yoke and is rotatably anchored to a yoke side611through a leg strap pivot613. A purpose of leg strap pivot613is to enable sufficient rotation of leg strap614to enable leg strap614to lie flat against the user's lower leg, distributing pressure evenly and reducing possibilities of pressure points and chaffing.

Flexibility in the sandal600to allow forward rotation of the leg in dorsiflexion is enabled by allowing yoke sides611to rotate. Rotation is enabled by a yoke pivot612which rotatably connects each yoke side611to an aft strap stanchion607.

A superior elastic anchor605connects a yoke side611to an elastic member603. The elastic member603may be made of a variety of elastic materials, for example rubber, silicone, thermoplastics, urethanes, etc and may be in a variety of shapes, such as round cord, flat cord, sheet or other shapes depending on the design. Elastic member603may be of an off the shelf material such as a bungee cord, or it may be custom shaped (ie: molded) for the application. Elastic member603may include two or more separate elements (two shown) or may comprise a singular element that is divided at the top (for example, Y shape) to enable connection to the medial and lateral yoke sides611via the superior elastic anchors605. Elastic member603may also be shaped, for example, through the use of a molded elastomeric component cast into a “Y” shape.

Aft Stanchion

The aft strap stanchion607of sandal600will be taller than in typical sandal applications. This additional height provides an ability to elevate yoke pivot612to a location that is closer to an axis of rotation of the ankle during use. To be clear, the elevation of a yoke pivot612on the medial side may be higher than a yoke pivot612on the lateral side to help keep the axis of yoke rotation similar to the axis of ankle rotation.

To help manage forces in the aft strap stanchion607, further reinforcement may be necessary. The aft strap stanchion607may be reinforced in a variety of ways, by judicious choice of materials, layers and thicknesses or by addition of supplemental aft stanchion stiffeners615. These stiffeners may be of same or different materials as the aft strap stanchion607.

Function

Force from the front of the user's lower leg is transmitted into leg strap614, which is transmitted into leg strap pivot613, which is transmitted into yoke side611during locomotion. With the benefit of yoke pivot612, the yoke614,611rotates to transfer force into the superior elastic anchor605, which is transmitted into elastic member603, which is transmitted into inferior elastic anchor604, which is transmitted into footbed602and thereby into the heel area of the foot. Components are described as independent elements herein, but may be constructed in various other ways known to a design in the sandal arts. For example the yoke sides611may incorporate a leg strap614and be one contiguous object which has sufficient flexibility in the strap area to obviate the need for a yoke pivot612.

Fold-Away

As with the other rotating aspects described herein, sandal600stores potential energy during dorsiflexion and returns it during plantar flexion. Yoke sides611and leg strap614may be rotated aft and worn behind or under the foot when support from elastic member603is not desired.

Spring Adjustment

As with other aspects, spring603may be tuned to various applications and also adjusted by the user to suit the user's needs. Elastic member603may be anchored to the yoke side611by a variety of means, including hook and loop fasteners, buckles, adjustable straps and the like.

Application of the Aspect in Various Environments

Sandals are used worldwide for a wide variety of applications. Sandals are often used in many lower income areas as a low cost footwear alternative. Many people, especially people of limited income, rely upon walking as their primary means of mobility. The ability of a sandal to offer improved gait performance can translate to an easier experience of walking, especially when one is relying upon walking as their primary means of mobility.

A person who weighs 600 N and who uses a sandal as disclosed herein with a 30N/cm spring rate may experience approximately 3 to 8% of ankle forces externalized out of their body and into the sandal during their gait. This assistance can facilitate mobility and dynamically offset the weight of a load carried by the user. For people who rely on walking for mobility, this can be a distinct advantage.

Application of an Open Yoke System in Other Footwear

This same type of open yoke energy management system may also be employed in closed shoes, such as running shoes or tennis shoes which are traditionally not sold as high tops. In the sandal aspect, the yoke614,611is supported by a yoke pivot612into an aft strap stanchion607. In a closed shoe such as a tennis shoe or running shoe, yoke sides611could be attached via a pivot into a sidewall of the upper of the shoe. The shoe may need to have additional support within its sidewall to prevent slumping or buckling.

When used in such shoes, their sidewall and upper may be supported by additional caging, by tension bearing stitching between the eyelets and the midsole, by the inclusion of stiffeners such as employed in heel counters, by adding additional layers of upper material, by extending the arch support or shank up the sidewall to behave as a stanchion, to incorporate a stanchion via a molded overlay on the outside of the upper, or related design methodology. By encasing a support member between the interior comfort layer of a shoe and the exterior surface of a shoe, one can restrict motion of the support member. Such an approach may be termed hoop banding force. Such hoop banding force may be supplied by orienting shoe laces and tension elements between the laces and other laces and between laces and the sole such that sagging of the support member is limited.

The vertical reach of open yoke system may vary according to application. For applications which require minimal force, the open yoke system may be created with minimal height sufficient only to avoid interference with the foot and any chaffing discomfort. For applications which require higher forces, the open yoke system may be extended to a significantly higher height to increase leverage and reduce the amount of force applied into the shin.

Aspect 7

Tan Boots Having a Cantilevered Yoke

Table of Reference Numerals:

Seventh shoe aspect700in the form of a bootoutsole701heel counter panel702lower collar703elastic sheet704collar yoke cantilever705cantilever support706leg collar707upper eye stay708anterior gusset709eyelets710quarter panel711lower eye stay712toe box713elastomeric material714heel counter715yoke reinforcement716cantilever reinforcement717sock liner and padding system718upper eye stay reinforcement719lower eye stay reinforcement720structural toe protector721ventilation hole730interface731integrated heel counter732radial reinforcement pattern733circumferential reinforcement pattern734eyestay integration735

FIG.15shows side views of a seventh aspect of a shoe, boot700.FIG.15is a drawing, for example, of a modified military boot700, with a collar yoke cantilever system that transfers force from a leg over a pivot to an elastic spring system.

FIG.15Ais an external side view of the aspect, andFIG.15Bis a side view of the same aspect with external layers removed to enable viewing of internal construction layers.

FIG.15Cis another rendering of an external side view of an aspect, andFIG.15Dis a side view of the same aspect depicted inFIG.15Cwith external layers removed to enable viewing of internal construction members.

Boot700has been modified to enable a variety of elastic spring combinations to be deployed in a manner that is consistent with various design and aesthetic constraints. For example, military boot standards typically require adherence with a code for uniforms. These codes often limit the addition of any additional nontraditional appendages to the exterior surface of the boot. For example, the use of metal hooks, buckles or appendages may be limited, deviation from color specifications may be limited and so on. Boot700as depicted and described herein enables integration of force management approaches which may enable boot700to remain within various uniform codes.

Many boots have similar designs to high top athletic shoes, especially hiking boots and other configurations such as law enforcement boots and boots worn by safety personnel. This enables boot700to practice principles of design of earlier-described aspects to incorporate an energy management system as described above as well as vice-versa.

A challenge with certain tall boots, including military boots constructed for warm weather or light weight boots, is that the portion of the collar which wraps the lower leg is often made of a low rigidity woven material, often as thin as a single ply canvas, woven nylon, duck fabric or similar. Adding additional materials to supply rigidity to the collar to enable a collar yoke as described in earlier aspects may not be optimal in such boots. Moreover, in order to maintain practicality, designs should enable the collar to release heat and moisture and maintain warm weather comfort.

In boot700, a technique is shown ifFIG.15that enables the collar to continue use of low rigidity canvas type materials for warm weather applications and still benefit from integration of other aspects of this disclosure.

Referring toFIG.15, boot700includes an anterior gusset709that interrupts a lower eye stay712from an upper eye stay708. The upper eye stay708is designed to have significant rigidity to enable it to support a collar yoke cantilever705. Similarly to a sail boat where the mast supports a boom, the upper eye stay708is able to support a collar yoke cantilever705with the assistance of at least one cantilever support706. Cantilever support706acts in tension to help connect the collar yoke cantilever705with the upper part of the upper eyestay708. Alignment with eyelets710allows the cantilever supports706to position their superior anchors to receive further support under tension.

Boot700may have two eyestays, upper708and lower712. Collar yoke cantilever705and cantilever supports706may be all cut from the same blank and be contiguous. Typical materials for boot construction include leather and heavy vinyl sheet among other materials. If these materials are not sufficient to maintain proper shape, these components may be reinforced. An under-layer of supportive material may be added. The upper eye stay708may be reinforced by an upper eyestay reinforcement719. Lower eyestay712may be reinforced by a lower eyestay reinforcement720. Collar yoke cantilever705may be reinforced by a collar yoke reinforcement716. Such reinforcement may include the use of materials such as plastic sheet, carbon fiber, leather, and other materials familiar in the art. Stitching between layers of elements may add further strength. These elements are shown inFIG.15BandFIG.15Don top of the boot's sock liner and padding system718which is presumed to be able to stretch as needed.FIG.15Dis a cutaway view of an aspect of the present disclosure.

Spring Rates

In this system, the collar yoke cantilever705can suspend a variety of elastic systems. Elastic sheet material704can be anchored below the collar yoke cantilever705and above the foot collar703and heel counter panel702defining at least one elastic member. The elastic sheet material704may include a variety of woven elastic fabrics, nonwoven elastic fabrics, fabrics with single and multiple directions of stretch, sheet materials, and others. Elastic sheet material704can displace the typical canvas upper material in this area, saving also the cost and weight of the typical material and keeping material costs lower as well as keeping any weight increases lower. Also, the elastic sheet material can be used in combination with an external material that has sufficient aesthetic, stretch and protective qualities but insufficient spring rate to enable desired force. Elastic force potential may also be integrated into an area of the sock liner and padding system718. Sock liner and padding systems need to accommodate the range of motion in proximity to the rear gusset. This may be accomplished in several ways, for example, by gathering sections of linier and bonding elastic material thereto or removing a section of traditional liner material or displacing traditional materials with stretchable material, especially in the gusset areas.

The spring rate of the elastic sheet material704may provide the entire elastic function of the system. In another configuration, the force of the elastic sheet material704may be augmented or replaced by a supplemental layer of elastomeric material714in either a sheet, cord, molded, or other custom shaped configuration. In yet another configuration, elastic sheet material704may be augmented or replaced by a powered system that imparts a compressive force that supplements the available force and power of a passive spring system alone. Such a powered system could include a motor, cable, solenoid, artificial muscle, pneumatic, hydraulic, combustion based solution in series or parallel with spring elements.

User Adjustable Spring Rates

In another variation, the supplemental layer of elastomeric material714may be adjusted by the user upon demand. By providing at least one user controllable internal anchor, a user can engage a supplemental layer of elastomeric material714upon the collar yoke cantilever705. Snaps, buttons, hook and eye, hook and loop are all methods of enabling adjustable tension on a supplemental layer of elastomeric material714within the boot.

One approach to engaging the supplemental layer of elastomeric material714is to have the material be anchored near the bottom of a heel counter, behind the heel counter away from contact with the skin. A connector such as a length of shoe lace material may be affixed to the top of the supplemental layer of elastomeric material714. This length of shoe lace would be of similar aesthetic uniform design but not be contiguous with the main lace used for tightening the boot. This connector lace could be guided past the collar yoke cantilever705and adjacent to a cantilever support706to an eyelet710, out one eyelet710, along the outside face of an upper eyestay708and back into another eyelet710, down adjacent to another cantilever support706, past the collar yoke cantilever705to the same or separate supplemental layer of elastomeric material714. In this way, the connector lace would lay flat against upper eyestay708when the supplemental layer of elastomeric material714is gently engaged, and could be pulled tight to a plastic hook on the opposite side eyestay708to more fully engage the supplemental layer of elastomeric material714. In this way, the engagement of the supplemental layer of elastomeric material714would be controlled by a connector lace and plastic hook of similar appearance to the main lace and plastic hooks of boot700, without need for supplemental knots, fasteners and the like. This configuration continues the principles of an energy management system herein that further support integration within footwear and conformity with required aesthetic limitations.

In applications without uniform regulations which prohibit external appendages, a number of other mechanisms may be employed to allow the user to control and adjust the spring tension. For example, cam lock systems, adjustment screws, tuning screws similar to those on guitars and the like may be used.

Reinforcement and Rotation

In all of these variations of boot700, the upper eyestay708will experience a downward force when the elastic system is engaged. To resist slumping down the leg, especially in hot weather boots and other with fabric collars, the upper eyestay708may be supported by the lower eyestay712as well as the foot collar703. These are shown in one contiguous material inFIG.15Awhich depicts an outer layer of materials, such as leather. This contiguous element can be further reinforced by the upper eyestay reinforcement719and the foot collar reinforcement720which anchors the unit to the sole (FIG.15B). These reinforcements are shown non-contiguous, with mating surfaces that resemble a ball joint. The point of rotation is designed to be aft of the anterior gusset709to move it close to the ankle joint. In this aspect foot collar reinforcement720passes over the heel counter715as well as the structural toe protector721, but may be incorporated with either. Said reinforcement elements, in a preferred aspect are designed integral within footwear between inner materials such as sock liners and padding and outer layers such as leather uppers. Said reinforcement elements, by virtue of their strength and anchoring to the sole provides the upper eye stay708with support to prevent sliding down the ankle as well as a favorable rotation point for driving necessary spring performance. Heel counter715may incorporate reinforcements as shown in integrated heel counter732. Integrated heel counter732includes ventilation holes730. Integrated heel counter shows how the heel cup as an integrated unit with the reinforcement elements, it must carry the necessary forces while resisting deformation. Integrated heel counter732provides an interface zone731. Such an interface zone ideally allows for rotation of the ankle, together with fore/aft laxity to resemble the actual ankle degrees of freedom, for example by allowing the ‘ball’ member to have a smaller radius than the ‘socket’ member. The interface is shown with the center of the shared radius above the interface as a means of providing additional support to the ankle yoke. The center of the shared radius may also be below the interface to more closely resemble the ankle joint and mortise. Integrated heel counter732ensures that ventilation holes730are oriented so that they preserve key aspects of strength. Ventilation holes730are arranged to enable integrated heel counter732to maintain a radial reinforcement pattern733that can bear forces emanating from the collar yoke, into interface zone731and transmit said forces through the mid sole and sole into the ground. Such arrangement helps resist slumping of the sidewall of the article of footwear when under a compressive load. Ventilation holes730are also arranged to enable integrated heel counter732to maintain a circumferential reinforcement pattern734that can assist in managing forces that augment the stability of integrated heel counter732. Such a circumferential reinforcement pattern734can be integrated with eyelet holes735or an eyestay.

Circumferential forces, also described in this application as “hoop banding” is a means of gaining additional benefit from maintaining a tensile load from the lacing towards the sole and heel. This tensile force acts like a band around a wooden barrel, and thereby counteracts the tendency of integrated heel counter732to slump while under load. Tensile force may be carried through the circumferential reinforcement pattern of the integrated heel counter732, or through other materials outside of integrated heel counter732. Integrated heel counter732may be designed to prevent said circumferential forces from placing undue force on the top of the foot, for example by selecting materials that resist this impingement under load, or by allowing the lateral and medial sides of the integrated heel counter to be oriented such that they abut each other (directly or through an intermediate object) when the laces are tightened. As forces upon interface zone731increase, there is an increased tendency to slump, and the material chosen for integrated heel counter732will be selected based upon the forecasted demands that will be placed upon that footwear, for example, lighter duty application may be supported by plastic type materials while more intense applications may be supported by composite type materials. Integrated heel counter732is shown in this aspect, but may be employed in other footwear aspects discussed in the aspects herein and beyond.

Integration of Collar Yoke

Together with the integrated heel counter732confers the benefits of a hinged ankle brace to the ankle/foot area. Because collar yoke and integrated heel counter732are integrated within the layers of the footwear, they receive the benefit of comfort conferred by padding and sock liner. As compared to wearing a brace on the foot inside the shoe, said comfort is realized through the benefit of separating the structural elements of the endoskeleton behind the sock liner and padding. This separation helps reduce irritation, friction, impingement, pressure points, heat build-up, moisture buildup and other factors that conduce towards discomfort. Yet another benefit of this integration is improved aesthetics—as the support elements may be incorporated without being apparent to the outside world. Yet another benefit of this integration is to overcome the need for a wearer to purchase a footwear that is larger than normally used, to allow room for a brace.

As an alternative to a typical hinged ankle brace, integration of elastomeric material714confers the benefit of maintaining a baseline pressure on the footwear, maintaining closer contact of the heel of the foot to the inside heel of the footwear thereby reducing opportunities for misalignment and discomfort.

The result is that the solution is appropriate for people who wish to protect their ankles from untoward forces to the ankle. This is beneficial to those wishing to gain a prophylaxis from primary injury, to find support during recuperation from an earlier injury, or to help prevent re-injury. The improved comfort, potential for metabolic performance improvement and ease of use, are hypothesized to overcome multiple reasons for not wearing an ankle brace. Improving compliance with ankle bracing provides a population based benefit by making it easier for more people to gain the benefits of bracing more frequently without the need for a separate brace and its associated discomfort and inconvenience.

Stitching for Rotation

The stitching of the eyestays708,712may be altered in the vicinity of desired rotation. Eyestays are typically stitched to the upper on their fore and aft sides. This may be altered in the rotation area, for example, by switching from straight stitching on the fore and aft sides to zig zag stitching in the rotation area to enable some laxity in the leather while in the rotation area. Or, the straight stitching from the fore side of the upper eyestay708may be crossed over the mid of the eyestays in the rotation area, and similarly the fore side stitching of the lower eyestay712may be crossed over the mid of the eyestays in the rotation area. These two intersecting straight stitches would then create an “X” at the center of desired rotation area. Even without crossing over, stitching may be configured in an “X” pattern or even a multi-point star pattern as found in an asterisk of various legs. Another pattern might include a vertical “U” shaped series of stitching that intersects with an inverted “U” shaped series of stitching. Woven or non-woven materials may be gathered and applied to external surface of the boot to provide improved strength and longevity across multiple flex cycles.

Applications of the Aspect

People wear boots with different vocational requirements than sneakers. Often, this means that the same pair of boots is worn for extended hours for repeated days. Boots are exposed to harsh terrain and a broad variety of outdoor climates. Military troops are often given a small yearly stipend of money that is used towards the purchase of boots, resulting in the demand for low cost boots which may lack higher priced features such as glove leather linings. New boots are often considered stiff and this stiffness results in significant motion of the foot within the boot during the gait cycle, as the foot tends to flex while the boot does not. This is further exacerbated when boots are purchased that do not have the desired fit to the user's foot. This lack of flexibility and comfort features can lead to the formation of unwanted blisters, calluses and sore spots.

Boots are typically worn as a primary piece of footwear across multiple activities. These activities may include low impact activity such as meal preparation or warehouse work for much of the day, interspersed with infrequent bursts of high impact activity such as running, jogging or marching.

The anterior and posterior gussets of boot700provide better range of motion of the boot when new. This allows the high collar of boot700to rotate evenly with the lower leg and the main part of the boot to stay stationary relative to the foot. This reduces unwanted motion and friction between the foot/leg and boot700and improves comfort.

The elastic sheet material can provide primary tension spring performance that supplies a low baseline of spring rate action. This low spring rate has the capability to pull the heel of the boot close to the heel of the foot, similar to a pair of suspenders. This reduces movement between the heel of the boot and heel of the foot, which is a primary cause of friction that leads to blistering and pain, thereby reducing the tendency towards blistering.

The primary tension spring force from the elastic sheet material also provides a low baseline of active support to the ankle system, thereby externalizing some tendon and muscle force outside the body and into the boot. This small benefit may accrue over a full day of use of the boots to reduce fatigue.

The supplemental tension spring force may be engaged when desired. For example, if the user is preparing for a hike or a march, the supplemental tension spring could be engaged prior to the start of the activity and released upon its conclusion. Thus, the performance benefits of the supplemental tension spring would be available on demand without requiring the user to have it engaged throughout the entire day. This can be beneficial when carrying backpacks and materiel. Each additional Newton of materiel translates to a corresponding increase on Achilles tendon force, typically cited as 1.2 to 3.0 depending upon activity & gait. A backpack weighing 270 Newton (˜60 pounds) will require additional exertion by the wearer carrying it. Using aspects of this disclosure with a spring rate of 30 N/cm, could offset 8 to 20% of the force of the pack upon the Achilles, thus delivering a significant dynamic weight reduction (dynamic reduction of 4 to 12 pounds) with a minimum addition of weight or cost to the boots.

The geometry of such a system enables it to transform some of the work into electrical current which can be stored or used as it is generated. For example, an elastic member may include a coaxial device that enables generation of electric current as the elastic element is stretched and or released. A variety of small power harvesting mechanisms may be employed, examples comprise but are not limited to solenoids, coils, piezoelectrics, micro-electric generator systems, reciprocating members to drive alternators, and the like.

More aggressive performance characteristics could be realized by the integration of high performance supplemental support systems. While boot manufacturing practices often use plastic sheet for heel counter reinforcement, it is also known that stamped metal pieces are common for use in steel toes and metal shanks. High performance plastics, fiberglass and carbon fiber are also known in high performance boot applications such as cold weather boots. As such, manufacturers familiar with such materials may choose to offer a boot with high strength reinforcements that would enable a more aggressive primary or secondary spring rate to be used.

Novel concepts described in this aspect of boot700may be adopted into other types of footwear, especially athletic shoes, trail running shoes, low hiking boots, etc. For example, inFIG.7Bvariations of the collar yoke cantilever and adjustability mechanisms are shown. Variation of a collar yoke cantilever stiffener139is shown as an example of how these techniques described for application in boots can be adopted into athletic footwear. Similarly, concepts from earlier aspects can be applied into the boot category.

Other aspects of footwear may come to the mind of one of ordinary skill in the art of footwear design through an understanding of the principles of the structural elements of an energy management system as described herein. Further variations than those described above are within the appreciation of one skilled in the arts and such variations are to be considered within the scope of the claims which follow.

Aspect 8

Detachable Lower Limb Yoke

Table of Reference Numerals:

Boot and yoke extension800Footwear with receptacle801Anterior gusset802Posterior gusset803Receptacle for yoke extension leg804Yoke extension805Vent holes806Tension adjusting mechanism807Connector808Interface between connector and elastic member809Elastic member810Interface between elastic member and fastener811Male fastener812Female fastener813Yoke extension leg814Front face815Rear face816Collar yoke817

FIG.16Bshows a side view of an eighth aspect of a boot and yoke extension800.FIG.16Bis a drawing, for example, of a modified military boot and yoke extension combination that transfers force from a leg over a pivot into and out of an elastic spring system.FIG.16Bis an external side view of the aspect.FIG.16Ais a side view, highlighting integration with pants.

Boot and yoke extension800has been modified to enable a variety of elastic spring combinations to be deployed in a manner that is consistent with various design and aesthetic constraints. For example, military boot standards typically require adherence with a code for uniforms. These codes often limit the addition of any nontraditional appendages to the exterior surface of the boot. For example, the use of metal hooks, buckles or appendages may be limited, deviation from color specifications may be limited and so on. Boot and yoke extension800as depicted and described herein enables integration of force management approaches which may enable boot and yoke extension800to remain within military uniform codes.

Yoke extension805provides an additional means beyond a collar yoke of harvesting force from the front face of the lower leg. Force may be harvested from the shin face of the lower leg jointly by a collar yoke817and yoke extension805or with all of the force being harvested by the yoke extension805.

Yoke extension805comprises a front face815that harvests force from a lower leg, rear face816that imparts force vertically through tension adjusting mechanism807, connector808, interface between connector and elastic member809, elastic member810, interface between elastic member and fastener811, male fastener812, female fastener813, which collectively transmit force into the heel area of the article of footwear801. Pivot forces are managed through yoke extension leg814into collar yoke817and into article of footwear801.

Because the front face815may contact the shin at a greater distance from the ankle joint as compared to any given collar yoke, it may harvest energy from the shin face with greater leverage and therefore requires less contact force. Front face815may also be designed with a larger surface area than possible in any given collar yoke. In such a way, a yoke extension805may have both increased leverage and increase surface area contact with the shin allowing it to harvest significantly more force from the front of the shin face and also reduce the pressure on the shin face.

In an aspect, front face815must have a surface area that is sufficient to distribute forces on the shin face of the lower leg that are within the tolerable limits for the application. Such limits may vary with, for example, the duration and significance of physical activity. For example an athlete competing in an intense short duration sporting event may be willing to endure high pressure and significant discomfort, where a pedestrian walking on their way to work may wish to avoid any discomfort.

Yoke extension805may be expanded in its surface area such that it also acts as a shin protector. Pairing a boot, shoe, sneaker or other article of footwear with a detachable shin protector has the opportunity to provide benefit to many users in both comfort as well as functionality. Shin protection is commonly worn in many applications. For example, shin protection is used in athletic pursuits such as soccer, vocational pursuits such as logging, and military applications for shin protection.

Front face815may be configured in a variety of fashions. It may be semi-rigid as shown in the drawings by creating a one-piece design with semi-rigid materials selected from a broad array of plastics, composite structures, metal allows, and combinations thereof.

Front face815may also be designed as shown inFIG.16Aand other figures herein—which create a shin face by suspending shoe laces, straps, fabric or other materials between opposing sides of a multi-piece yoke. Replacing a semi-rigid design with a non-rigid material may reduce the impact protection of front face815, but offers a variety of other benefits.

Yoke extension805as shown in the aspect ofFIG.16Bmay be attached and detached by a user to the collar yoke817of an article of footwear801in a manner that enables yoke extension805to rotate at a hinge point, positioned such that the axis of rotation of the hinge point is along or in near proximity to the axis of rotation of the ankle joint.

Yoke extension805is connected to article of footwear801in a manner that enables it to be attached and detached at will by a user without special tools. Such attachment must have sufficient strength that it allows anticipated forces to be conducted while under dynamic load without failure of the connection. Article of footwear801may have structural elements below the ankle that provide sufficient stability to accept the associated forces.

Enabling yoke extension805to connect and disconnect from article of footwear801allows a user to have greater personal control over the assistance provided. Article of footwear801may be configured with a small amount of spring force in posterior gusset803, and the addition of yoke extension805may augment the baseline spring force of article of footwear801. Separating yoke extension805and article of footwear801also provides the ability for the yoke extension805to be integrated into an article of functional lower limb clothing, such as pants, long underwear, body suit, etc.

A wide variety of means may allow the yoke extension805to be detachably and rotatably attached to the footwear801. Yoke extension805may be attached to collar yoke817by a variety of means including providing a sleeve or holster such as receptacle for yoke extension leg804that receives yoke extension leg814, by providing mechanical fasteners to connect yoke extension leg814to collar yoke817, by providing a variety of other means including buttons, laces, hook, hook & loop, or other known approaches. Many other means may be employed to connect extension yoke leg814to article of footwear801in a manner that augments the rotational hinge qualities of the interface between collar yoke817and the base of article of footwear801, including the integration of a ball & socket joint, a heim joint, a rod end, a ball and socket pair in which the male rotating ball element's radius is smaller than the radius of the female socket side of the joint thereby providing some fore & aft laxity, etc.

Tension adjusting mechanism807is responsible for providing an upper anchor upon rear face816for connector808and providing adjustment to the available length of connector808. Tension adjusting mechanism807may be a rotating ratchet, mechanical ratchets, cam-lock devices, winch, knob, linear accommodating device, motor powered device, slide lock mechanism, solenoid, hook and loop fastener, hook & eyelet, cleat, anchor holes, laces with knots, etc.

Tension adjusting mechanism807may be powered by the user's strength, by stepper motor, by stored elastic energy, by a motion powered ratchet, etc. There is a variability in load upon the tension adjusting mechanism807such that the effort to adjust the mechanism is easier during the swing phase of the gait when the user is plantar flexed.

Connector808may be adjustably attached to tension adjusting mechanism807. Connector808also connects to elastic member810through interface between connector and elastic member809. Connector808may comprise a variety of tension bearing materials, including a shoe lace, woven cord, string, cable, etc. As the yoke extender will have medial and lateral sides, there are a variety of ways to enable adjustment. In the aspect depicted inFIG.16B, a single adjusting mechanism807controls a single connector808. Connector808is anchored to the medial instance of rear face816in a fixed fashion then proceeds through a loop at interface between connector and elastic member809and continues until it adjustably attaches to adjusting mechanism807which is mounted on the lateral instance of rear face816. Pre-load tension may also be adjusted by having separate adjusting mechanisms807for the medial and lateral sides of yoke extension805.

Elastic member810may be a single element, or there may be multiple elements. For example, multiple spring rates and lengths may be deployed to provide non-linear spring rates and for variable performance depending upon free length of connector808.

In an aspect, the connector808is longer than the elastic member810. The tension adjusting member807allows elastic member810to be pre-loaded very precisely and to a desired state. This allows, for example, the starting point of spring force to be adjusted such that spring force may be set by to accommodate requirements of the user. Tension adjusting member807may pre-load and stretch the elastic member810to a multiple of it's the elastic member810's initial length. This provides a great variety of performance levels in the same system.

Lower end of the elastic member may be anchored to the article of footwear in a variety of ways. Elastic member810. The interface between elastic member and fastener811, may attach elastic member directly or through a connector to male fastener812. Male fastener812attaches to female fastener813. Female fastener813is anchored to article of footwear801. The use of the terms male and female with regard to male fastener812and female fastener813are for descriptive purposes but not intended to limit the ways in which elastic member810may be anchored to article of footwear801. InFIG.16Bthe preferred aspect is shown with male fastener812and female fastener813to be of interlocking pairs of any variety of materials suitable for the load and environmental and mission conditions. Other means of attachable and detachable fastening may be used.

Use of increased spring rates in the elastic member810may require advanced materials selection for the support members within article of footwear801and yoke extension805components.

Biofeedback may provide intelligence to adjust the pre-load of elastic member810to a level that is optimal for the users needs. When user is running the paid out length of connector808may be shortened to increase pre-load. This can provide superior performance while also reducing the need to engage high pre-loads while walking or while trying to accelerate to a running pace. If desired, user is allowed to reach a steady state of running, hiking, marching, etc before the unit adjusts pre-load and adds tension.

Biofeedback may also sense when the user is in a mode where surplus energy may be harvested (i.e. downhill walking or hiking, casual walking). This would allow electricity generating devices to work in parallel with the passive spring-based devices to harvest electrical power when minimally disruptive and/or helpful.

Aspect 9

Detachable Lower Limb Yoke

Table of Reference Numerals:

Boot and yoke extension900Footwear with receptacle901Anterior gusset902Posterior gusset903Receptacle for yoke extension leg904Yoke extension905Vent holes906Tension adjusting mechanism907Connector908Interface between connector and elastic member909Elastic member910Interface between elastic member and fastener911Male fastener912Female fastener913Yoke extension leg914Front face915Rear face916Collar yoke917Supplemental power element918Rotation point919Body wear920Layered shin interface922

FIG.17Ashows a side view of a ninth aspect of a boot and yoke extension900.

FIG.17Adepicts a military boot and yoke extension combination that transfers force from a leg over a pivot into and out of an elastic spring system.FIG.17Ais an external layered side view of the aspect.

FIG.17Bshows yet another layered cutaway side view of another aspect.

This aspect highlights body wear920, which was mentioned in other aspects, but not shown to maintain ease of explanation. Yoke extension905may be integrated into body wear920in a permanent or removable fashion. Body wear920comprises a variety of functional clothing, such as uniform trousers, coveralls, long underwear, pants, socks, shin protection, and other articles of clothing, including clothing for the lower limbs as well as the trunk.

Front face915is shown here as a separate element that bridges between lateral and medial sides of yoke extension905. While yoke extension805of the previous aspect is shown as a continuous material from lateral to medial, yoke extension variation905has two separate sides that are bridged by elements associated with front face915. Rotation point919provides the ability for front face915to lay flat against the shin face.

As shown inFIG.17C, front face915may comprise a variety of woven or non-woven fabric elements as shown in layered shin interface922. This may include webbing, foam padded fabric, mesh, combinations of materials, etc. Front face915may be integral with body wear920where material of body wear920becomes a layer of the shin interface922. In such a way, yoke extension905utilizes construction elements of body wear920to serve as front face915. Or, expressed in different words, body wear920may be improved by integrating yoke extension905such that the body wear is able to carry force loads. For example, if medial and lateral sides of a two-piece yoke extension905are sewn into a pair of pants, the front surface of the pants may be employed as the front face915. In such a way, yoke extension905may share functional utility with body wear920, or using different words, body wear920may share functional utility with yoke extension915. Similarly, body wear920may not be required to transmit load, but rather provide a suitable pocket to hold the yoke extension905in place. In such a configuration, pocket may allow yoke extension905to be hidden from the outside. Pocket may have openings to allow yoke extension legs914to be inserted into boot900and cables and tension also to pass through the openings and attach to the article of footwear.

Similarly, elastic member910may be integral with body wear920. For example, elastomeric elements may be sewn into the body wear920, or a highly stretchable fabric may comprise the lower rear leg section of body wear920, or some combination of stretchable material together with elastomeric element. In so doing, the fastener912may be selected such that it provides a secure fitting without being disruptive if the fastener was not attached to the article of footwear. Elastic member910may be incorporated in series above than the upper anchor or the yoke extender905with additional elastic members to serve the knee system or the rest of the body. Such additional elastic members may carry spring potential energy, propulsion, or compression/propreoception elements. In another aspect, elastic member910and connector908may travel through an opening in the body wear920.

Supplemental power element918may be integrated above or below elastic member910. Supplemental power element918is designed to provide a twitch-like contraction similar to a muscular contraction. Contraction force may be powered by a variety of means, including electrical, liquid fuel, gaseous fuel, accumulator, hydraulic or pneumatic pulse, electro-rheological gel, motor, etc; such power source perhaps being mounted to the yoke extension905, article of footwear900, or on some other device which may be connected to the yoke extension905via a connector such as a cable.

In an aspect, supplemental power element918may provide a contraction of 0.1 cm to 5 cm or more. Contraction occurs in similar time required to achieve proper plantar flexion through toe-off which is approximately 0.10-0.20 seconds in duration for typical gait duration of 1.1 seconds. Many variations of the supplemental power element will produce a significantly faster contraction speed than 0.15 seconds. For example, propane ignited or electrical solenoid powered systems may exert their contractions in less than 0.05 seconds. External power element918may fire rapidly and the resulting pulse of energy may be impractical to deliver directly into the body. The benefit of arranging the linear contraction of the supplemental power element918in series with the elastic member910is that elastic member910can absorb a rapid contraction of kinetic energy, damp high frequency pulses, store potential energy, and then deliver stored potential energy over time as the user moves in plantar flexion towards toe-off. As such, the notion of using a fast-twitch type of supplemental power unit918is greatly simplified.

Contraction may be timed to coincide with the start of plantar flexion approximately during mid-stance. This can be evaluated and measured by an electronic or mechanical control device by evaluating ankle angle and observing when the dorsiflexion angle has reached its peak and when it is staring to reduce and tend towards plantar flexion. It may also be evaluated by a variety of other means, for example, analysis of strain gauge data to understand tension in the elastic member910or at anchor points; or through other means such as accelerometers or a combination of signal processing to determine optimized firing time.

Depending upon the speed of contraction, elastic member910in series with supplemental power element918may need to be supplemented by a damping system. A parallel length of an elastomeric material may be integrated adjacent to elastic member910. Alternately, the material selection for elastic member910may include a variety of materials, some of which may be selected for their damping qualities, such that harmonics and pulses are damped without wasting too much energy as heat.

One such approach for delivering compression force is through electrorheological materials and devices. Such materials and devices may be applied in parallel or series with other elastomeric materials to provide a solution that has a natural spring rate, as well as the ability to provide propulsive force. Such materials may reside in the region of the elastic elements, or they may be incorporated into the sole of the footwear, along the upper anchor point or elsewhere.

In another aspect, supplemental power element may be an electrorheological materials and devices, an electric motor, a pneumatic device, a hydraulic device, a linear actuator, and the like.

One such linear contraction motor may be derived from a free-piston engine type of arrangement. In such an arrangement a piston may be fired within a cylinder to impart a linear force. A combination of springs on either side of the piston provide a natural return to a state of readiness while in a static mode. Such a free piston would need to operate at approximately 60 to 80 complete cycles per minute, which is rather low compared to a stock two cycle design. As such, the dwell between cycles would be significant and require that the ignition chamber be of appropriate volume to accept a fuel mixture and be capable of ignition without an active compression activity such as would be provided by a starter-motor on a traditional engine. While this lack of a compression event may limit efficiency, the power available in a free piston arrangement surpasses the power required for a body-mounted application. As such, a reduced efficiency would be acceptable for this application. Having a lower compression will also reduce the sound signature of the free-piston engine's intake and exhaust activities, which is highly desirable in military applications.

Supplemental power element918may be mounted in a variety of positions. In the aspect shown, it is positioned in series with connector908. Supplemental power element918may also be anchored rigidly to article of footwear901or yoke extension905.

Not shown inFIGS.17A-Cis a concept of applying multiple tension carrying devices. For example, mimicking the Talofibular and Calcaneofibular ligaments, oriented to provide additional joint stability and resist inversion and eversion forces. Also, two or more exotendons that parallel the Achilles on the lateral and medial sides, so that there is an opportunity to reduce ankle inversion and eversion forces, may be incorporated in to boot and yoke extension900.

Force Diagrams and Hoop Banding

FIGS.18-19depict force diagrams associated with a yoke extender system. The force path of the system changes as compared to a low cut ankle boot or sneaker with the collar yoke integrated with less height above the ankle joint. As the height of the collar yoke and yoke extender increases above the ankle, several changes occur in the force diagram. Given a constant spring force, as height above ankle increases, the amount of force on the front face of the shin decreases as a result of the increase in leverage. Assuming that the collar yoke or yoke extender primarily relies upon a sliding interface between the front of the shin and the collar yoke or yoke extender front face, then there is only minimal vertical force exerted from the interaction with the front of the leg. The combined forces from the spring element at the rear of the unit and the front interface with the leg therefore impart a downward and forward force upon the hinged joint that aligns in proximity with the ankle joint's axis of rotation.

The higher elevation of the collar yoke or yoke extender results in more force being oriented closer to vertical. For example, in very short collar yokes, much force in transmitted near parallel to the eye stays at the top of the upper—forward and downward. In very tall yoke extenders, the forces are more vertical.

The rotation of the ankle changes the force dynamics. For example, as the ankle dorsiflexes, and the ankle joint angle becomes closed, the forward force through the hinge joint increases relative to the vertical downward force. Knowing the force dynamics experienced by the hinge joint, we can better understand the requirements upon the sidewalls of the footwear and any stiffeners that support the hinge joint. The sidewalls of the shoe will likely be reinforced to carry this force into the sole, so that forces are circumvented around the foot. This will reduce strain on the long arches of the foot and may reduce likelihood of injury or assist recovery after injury.

Several aspects have shown a variety of stiffeners and hinge support mechanisms. These approaches are shown to demonstrate various approaches and can be applied in a variety of aspects, not just the aspect shown in the figure in which it is described. As spring force and preloads increase, the need for internal support of the hinge points also known as rotation zones increases. Under significant force, sidewalls of the shoes will slump. Stiffeners and endoskeletal support members provide a mechanically sound foundation for the hinge & rotation points thereby maintaining vertical, lateral and fore/aft, and torsional stability.

The hoop banding effect is described herein as the support provided when an element is sandwiched between two elements, an interior fixed element and an outer cicumferential element. As an example, imagine a 1 cm square rod of balsa wood and imagine the compressive force it could withstand prior to failure as a result of buckling or slumping. Now, imagine the same balsa rod sandwiched against a 15 cm diameter pipe, wrapped tightly by duct tape. In the wrapped aspect, the balsa can carry a significantly higher compressive load because it is restrained from buckling in multiple directions. We call this stabilization approach “hoop banding”. Similarly, hoop banding may provide endoskeleton elements with additional stability and capacity than could be achieved without hoop banding. The foot acts as the inner element and the body of the shoe provides the circumferential wrap. Circumferential force may be provided by tightening the laces of the footwear. Laces, eyelets and tension elements that support eyelets may need to be positioned such that their force will accentuate hoop banding effect. Hoop banding will magnify the compressive load carrying capability of internal endoskeletal members. This allows the footwear manufacturer to create a circumferential force that maintains the shape of an endoskeleton even under load. Significant downward force can be carried through the body of the footwear and any support endoskeleton without having to pass through the foot.

The solution described herein may be equally considered as a mechanical system integrated into footwear and body wear as much as it may be considered as footwear with an integrated mechanical system and bodywear with an integrated mechanical system. It is believed that a minimalist embodiment may be commercialized at a price that is sufficiently affordable so as to be reasonable for people of ordinary means (athletes, recuperating patients, military personnel, mail carriers, etc).

Supplemental Power Element—Fuel Power

Table of Reference Numerals:

Supplemental Piston1000Fuel1002Fuel injector1004Fuel line106Casing1008Piston base1010Return spring1012Ignition chamber1014Piston base1016Connecting rod1018Air intake1020Piston ring1022a, bPiston return shock dampener1024Spark plug1026Piston1028Exhaust outlet1030a,bNoise attenuation chamber1032Exhaust port1034

Referring now toFIG.20, a cutaway side view of supplemental power element918, wherein supplemental power element918is a supplemental piston1000powered by fuel1002in accordance with an aspect of the present disclosure, is shown.

FIG.20is an example of a supplemental power element to provide compressive force in series or parallel with elastic member(s) of any aspect.

Supplemental power element918is shown explicitly in aspect9shown inFIG.17s.17A-C, but supplemental power elements918may be applied to other aspects and at additional locations. Many approaches may be used to provide compressive force.

FIG.20shows an arrangement akin to a free piston engine design. In an aspect, a solution would include a small reservoir of gaseous fuel1002—such as propane, propane/propylene mixtures, methylacetylene-propadiene propane, acetylene, etc. Fuel1002may include carbon constituents alone or a mix of carbon constituents and air or oxygen. Oxygen may be supplied or supplemented through natural aspiration or a compressed oxygen cylinder. Supplemental power elements918may at least partially be constructed from ceramic, composite, or other lightweight materials. Portions of supplemental power element918may be constructed of materials chosen for their favorable sealing capabilities and low dependence on oil-film type lubrication. Fuel may be introduced into cylinder1008via a fuel injector1004. Fuel injector1004may further comprise a fuel line1006connected to a fuel source on one end portion and fuel injector on another end portion and configured to transfer fuel1002from the fuel source to fuel injector1004.

In an exemplary state, the following four strokes occur.

Stroke 1—dorsiflexion will pull the sliding piston during a 0.3 to 0.4 second period as the leg rotates over the ankle prior to mid-stance. Sliding piston would include a piston1028and a connecting rod1018. Connecting rod1018would protrude rigidly from the top of piston1028, through the combustion chamber1014, through a sealed orifice in the roof of the combustion cylinder1008. In such a top-mounted connecting rod design, we are able to attain a compressive force during the combustion stroke. Mounting the end of the top mounted connecting rod1018and the body of cylinder1008in series with the elastic element allows the system to experience the forces within the elastic member system. As dorsiflexion increases, tension forces move the sliding piston against cylinder1008and compress the air in combustion chamber1014.

Stroke 2—Fuel1002will be introduced, the volume of which will further increase the cylinder pressure. Spark ignition, provided by a spark plug1026, will detonate the mix and the piston1028will be forced away, creating a compressive pulling force on the elements to which it is attached.

In such a way, the supplemental piston1000provides 1 to 5 cm or more of compressive twitch force travel—similar to muscle.

Near the end of piston travel in stroke 2, during the end of the combustion cycle, cylinder1008is vented out the bottom of the shaft1010, similar to a 2 stroke engine, to discharge exhaust into a noise reduction chamber, which is then followed by the opening of an inlet valve1020to admit fresh air. In the figure example shown, inlet valve1020is embedded into connecting rod1018, other inlet valve1020configurations can be substituted as needed. Piston1028pushes against a return spring1012which assists in returning the sliding piston back to a compression stroke.

The strength of return spring1012, weight of piston1028, length of travel, mean effective pressure of combustion and other factors will determine dynamic motion of supplemental piston1000. The system can be tuned to operate in a 2 stroke or 4 stroke mode. The two stroke mode would repeat at this point, the strength of the return spring starting the compression stroke, however the 4 stroke description follows here.

Stroke 3—Following the combustion stroke, return spring1012pushes piston1028back into cylinder1008. This coincides with the swing phase of the gate.

Stroke 4—This return creates a rebound which expands cylinder1008back to the open position, providing a shorter duration secondary venting of exhaust and providing fresh air inlet.

The beginning of stroke 4 allows return spring1012to load and start piston1028moving in the compression direction again which starts stroke 1 again. Dorsiflexion action continues to pull piston1028and compresses the air in combustion chamber1014. Within a short time of attaining the maximum point of dorsiflexion, fuel is injected into combustion chamber1014and the fuel air mix is then ignited.

Given a bore of approximately 1 to 1.5 cm and compression in combustion chamber1014of 2 to 4 bar (resulting from both dorsiflexion based compression of naturally aspirated air, together with injection of high pressure gaseous fuel1002), may yield a peak combustion pressure of approximately 10 to 20 bar. This would result in a peak force of approximately 75 to 150 Newtons.

Piston1028may comprise one or more piston rings1022(labeled, for clarity, as piston rings1022a,binFIG.20). Piston ring1022is configured to facilitate, among other traits, smooth movement of piston1028within cylinder1008. Piston ring1022may also provide an air tight barrier to prevent premature release of the fuel and air mixture in combustion chamber1014.

Cylinder1008may further comprise a piston shock dampener1024. Piston shock dampener1024may be a flexible ring placed in contact with the top portion of cylinder in the path of piston1028. Piston shock dampener1024may be configured to contact piston1028on the upstroke of piston1028and compressively absorb kinetic energy from piston1028.

Exhaust gases may exit cylinder1008by first passing through one or more exhaust outlets1030(labeled, for clarity, as exhaust outlets1030a,binFIG.20) located on the cylinder walls. Exhaust gas may then pass into a noise attenuation chamber1032, configured to absorb and deflect sonic energy via, for example, irregular surface contours. Exhaust gases may leave supplemental piston1000via one or more exhaust ports located on noise attenuation chamber1032.

Patella Bridge Knee System

Table of Reference Numerals:

Patella bridge knee system1100Clothing1102Femur section1104Hammock1106Upper tension device1108Tibia member1110Hinge1112Lower tension device1114Footwear1116Force carrying member1118Belt1120Knee cushion1124Damper1126Thigh strap1128

Referring now toFIG.21A, a side view of a patella bridge knee system1100, in accordance with an aspect of the disclosure, is shown.

Patella bridge knee system1100comprises a tibia member1110and a femur section1104. Such systems can be developed to utilize yoke extension905described earlier (e.g., with reference toFIGS.16-17B) as a platform to support a device that spans the knee cap (patella). Tibia member1110may comprise boot and yoke extension device900, wherein yoke extension905and the associated portions have been configured to extend to a location near the patella. For example, this would require the shin guard to be longer and extend up close to the patella without interfering with the range of motion of the patella or the ligaments & tendons associated with the patella. An extended shin guard would then provide a platform on top of which a system could be built that would enable a tension device to be spread across the top of the patella. The bridge would prevent interference of an elastic member system from rubbing against any sesamoid activity. In another aspect, tibia member1110comprises only a portion of boot and yoke extension device900.

In an aspect, the portions of tibia member1110proximal to the patella extend around the lateral and medial sides of the patella and are thicker than other portions of tibia member1110, providing a larger moment arm between hinge1112and upper tension device's contact point. This increases the leverage of system1100.

Tibia member1110may be horse-shoe shaped comprising a rigid front face which physically connects the lateral and medial portions of tibia member1110. In another aspect, the lateral and medial portions of tibia member1110are joined by flexible members (not shown inFIG.21B) configured in a fashion similar to hammock1106.

Patella bridge knee system1100comprises femur section1104above the patella similar to yoke extension region of boot and yoke extension device900. Such a semi-rigid platform may be created with a yoke type of device that is held in place by elastics. Femur section1104may also be integrated into body wear1102, such as pants, thereby depending upon the wearers waist belt and or suspenders to prevent pulling the pants down.

Femur section1104may be a single piece configured to provide a forward upper anchor or actuation point for upper tension device1108.

In an aspect, femur section1104is held in place via a hammock1106. Hammock may be an elastic member connected on one end portion to the lateral portion of femur section1104and connected on another end portion to the medial portion of femur section. Both connections may occur at a similar vertical height. In another aspect, the vertical connection location of hammock1104varies on the lateral and medial portions of femur section1104in order to comfortably rest upon the user's body. Hammock1104is configured to hold patella bridge knee system1100. Hammock1004also provides the necessary force for patella bridge knee system1100to extend the leg at the knee joint.

Patella bridge knee system1100may comprise an upper tension device1108which bridges across the top of the patella and provide an external tendon to assist the knee joint in extending, thereby reducing metabolic work. On one end portion, upper tension device1108may be connected to femur section1104. On another end portion, upper tension device1108may be connected to tibia member1110.

Upper tension device1108may comprise a tension adjusting mechanism, connector, interface between connector and elastic member, elastic member, interface between elastic member and fastener, male fastener, and female fastener, which collectively transmit force from femur section1104to tibia member1110in a similar in operation to other aspects of the present disclosure (e.g., transferring force from yoke extension805to heel area of article of footwear801).

Femur section1104and tibia member1110may be movably connected near the user's patella via a hinge1112. In an aspect, hinge1112is configured in a fashion similar to yoke pivot612of shoe600, as shown inFIG.14. In another aspect, hinge1112is configured with two axes of rotation, similar with other mechanical braces available commercially. In another aspect, hinge1112is configured with two axes of rotation, similar with other mechanical braces available commercially.

Patella bridge knee system1100may comprise a lower tension device1114which bridges from a portion of tibia member1110to footwear1116, providing an external tendon to assist the ankle joint in operating, thereby reducing metabolic work. On one end portion, lower tension device1114may be connected to tibia member1110. On another end portion, lower tension device1114may be connected to footwear1116.

Lower tension device1114may comprise a tension adjusting mechanism, connector, interface between connector and elastic member, elastic member, interface between elastic member and fastener, male fastener, and female fastener, which collectively transmit force from tibia member1110to footwear1116in a similar in operation to other aspects of the present disclosure (e.g., transferring force from yoke extension805through an elastic or an elastic together with a powered system to heel area of article of footwear801as well as transferring force from yoke extension805through a rotatable object to ground).

Such a system may be designed to benefit from active devices which provide the height above the patella to prevent interference and which also can contribute force to the system. Such devices could respond to input by raising or lowering themselves vertically on a hinged rotation, or provide tensile force to force carrying members such as upper tension device1108and lower tension device1114.

Clothing,1102, such as trousers, may have pockets designed to receive portions of patella bridge knee system1100. Additionally, pockets and channels between layers of fabric may be provided which create pathways for force carrying members, such as upper tension device1108and lower tension device1114.

Now referring toFIG.21B, a side view of patella bridge knee system1100, wherein patella bridge knee system further comprises a hip anchor, in accordance with an aspect of the disclosure, is shown.

In an active system, an elastic member would span across the patella and be anchored above and below the patella. Active systems could impart a force across the patella in a variety of ways. One way would be to activate the anchor points so that they could pre-load tension across the elastic member. Another way would be to activate the members which provide elevation across the patella. By articulating the bridge members to provide additional height, two benefits would be accomplished. The elastic member stretched across the patella would experience a longer distance of stretch for an equivalent amount of knee rotation, thereby increasing force while the bridge members were extended. And, the elastic member stretched across the patella would impart a greater force on the leg, as the leverage would increase.

System1100elements may be activated in a variety of ways—rotating 10 to 60 degrees similar to pin ball machine flippers; expanding vertically in a linear piston fashion; etc. The objective is to increase at least the height of the bridge elements and their separation also where possible. In such a way, the distance between the points across which the tension system travels increases and the leverage upon the leg increases.

Such dynamic system1100elements may be powered electrically, such as by a solenoid or step motor, hydraulically or pneumatically, by combustion, etc.

A controller would activate the dynamic bridge elements in the propulsive phase of the gait, where straightening of the knee join propels the person up and forward. By adding external power through the dynamic bridge elements, less effort is required during negative work and added benefit is gained through positive work. Knee extension force may also be imparted by placing force on a cable or other such tensile element that is oriented above the hinge point.

Similar to a hinged knee brace, such a device also provides a hinged knee joint that can assist in maintaining joint stability to prevent injury or aid in recuperation. By integrating the rigid members inside clothing, such as a pair of trousers, as shown inFIG.21B, it provides the ability for a user to don the device easily and wear it all day. The concealed aesthetics are pleasing. The user can adjust the tension of how tightly the femur segment is attached to the leg. This allows less conformation between device and leg (greater joint laxity) when the user has the device secured loosely and vice versa.

Patella bridge knee system1100may be integrated into clothing1102, such as trousers, via the incorporation of a force carrying member1118(e.g., an elastomeric member) and a belt1120. Force carrying member1118may connect on a first end portion to a portion of femur section1104, such as the top portion of femur section1104. Elastomeric member may connect on a second end portion to a hip anchor, such as a belt1120. The hip anchor is configured to removably connect to user and provide a point for transferring force to and from the user. In another aspect, hip anchor is a portion of clothing1102, such as a pant leg. Force carrying member1118may comprise a spring element, a powered element or both in parallel or series.

In aspects comprising force carrying member1118, patella bridge knee system1100may provide the motive force to extend the hip join during appropriate portions of the gait cycle, as well as proprioception to help users better maintain proper posture. This may help prevent injury.

Force carrying member1118and other elements of patella bridge knee system1100may be fitted within a layer of clothing1102(e.g., trousers) to be concealed from the outside. It may also be fitted in other types of garments, such as long underwear, body suit, jump suit, etc.

Clothing1102may be designed to share in the carrying of some of the force loads. For example, where patella bridge knee system1100comprises hammock1106, the fabric of the trousers may be connected to hammock1106and serve as a force carrying device. In another aspect, a separate hammock1106may simply reside in a pocket within the trousers and be removably connected to system1100.

Force carrying member1118may work passively or in conjunction with a powered device in series or parallel to provide more extension power to the hip joint. Force carrying member1118may be attached to a fixed belt, an adjustable belt or an electronically actuated device.

Patella bridge knee system1100may further comprise a knee cushion1124. Knee cushion1124may be configured to reduce forces imparted on the patella by other portions of system1100. Knee cushion1124may be movably connected to portions of tibia member1110and femur section1104. Knee cushion1124may be removable.

Now referring toFIG.22, a graph depicting the angle of a user's angle during a typical gait cycle and input from a powered device, wherein the powered device is a portion of aspects of the present disclosure and is adapted to provide or harness power during the gait cycle, in accordance with aspects of the present disclosure, is shown.

Now referring toFIG.23, a graph showing tension within a spring anchored to portions of a device according to the present disclosure, wherein the spring has been preloaded, in accordance with aspects of the present disclosure, is shown.

Patella Bridge Knee System

Table of Reference Numerals:

Boot700Dampers740Patella bridge knee system1100Dampers1126Thigh strap1128

Now referring toFIG.24, various side views of patella bridge knee system1100, wherein the system comprises dampers, in accordance with aspects of the disclosure, are shown.

Patella bridge knee system1100may further comprise one or more dampers1126(labeled, for clarity, as damper1126a-cinFIG.24). Dampers1126are configured to absorb and dissipate forces imparted on system1100joints.

In an aspect, dampers1126may be removably attached to portions of patella brisge knee system1100such that damper1126may absorb and dissipate shocks (e.g., landing forces when a parachutist impacts the ground), rather than the joint associated with damper1126, or the user's body. Endoskeleton allows for dampers to be inserted on either side of the joint on a detachable basis to enable attenuation and dissipation of forces when required. For example, during parachute landings devices can absorb landing force and dissipate untoward forces rather than shunting them to a neighboring joint or bone.

Damper1126may be designed to be easily attached and removed and carried in a pocket. This offers a superior solution to hook and loop wrap-around parachute ankle braces which have been highly successful in reducing injury but which are typically too cumbersome to be worn in combat.

Dampers1126may be positioned laterally and medially. Damper1126may comprise pneumatic or hydraulic dash-pot type dampers, rippable stitch fabric dampers (as used in safety belts), aerogel based dampers, variable rigidity fabrics, variable stretch fabrics, or other devices that impart friction to dissipate energy and force. Variable rigidity fabrics may be passive, which are capable of increasing resistance to flexibility the faster they are deformed, and may comprise one or many layers of such fabric; and variable rigidity fabrics may be active, which are capable of increasing resistance to flexibility through controlled electrical input, and may comprise one or many layers of such fabric. Many of such fabrics have directionality to their resistance, and when orienting such fabrics, the direction of resistance would align with the direction necessary to resist inversion and eversion motion. Similar to variable flexibility fabrics, variable stretch fabrics resist expansion in one or more directions. Orientation of the controlled stretch property would align with the vertical across the gussets.

Damper1126may be positioned in other directions in order to dissipate energy in such axes. Such devices may also be influenced by forces applied to the feet so that dampers positioned laterally, medially, anteriorly and/or posteriorly respond differently. This may be controlled electronically by sensors and force input. It may also be actuated by a multi-chambered ‘airbag’ below the sole that displaces a fluid such as air into dampers. If the medial side of the foot lands first, it might cause inversion, thus the displaced fluid would charge the lateral damper to provide extra resistance to inversion.

In an aspect, patella bridge knee system1100is integrated into clothing1102, such as a pair of trousers, allowing users to wear system1100all day with comfort. In order to further facilitate comfortable usage, it is envisioned that user will adjust the tightness of the femur section1104via adjustment of thigh strap1128. Thigh strap1128may be a hook & loop adjustable strap across the top of the quadriceps hidden within the trousers.

Users who wish to have greater conformation between the leg and the device will tighten thigh strap1128. Tighter straps increase the ability for the device to manage joint stability. As such, tighter straps can lead to reduced laxity of the leg and endoskeleton system. This allows people to wear the devices at a degree of tightness that they find comfortable and increase tightness when needing extra joint stability or extra kinetic energy recovery

Now referring toFIG.25, a graph of treadmill test results by various test subjects when utilizing aspects of the present disclosure, is shown.FIG.25demonstrates that rudimentary prototypical devices created for the test were capable of influencing metabolic demand.

Further laboratory testing in university settings of volunteer participants under IRB approval have continued to show unanticipated benefits, including increase in jump height, increase in jump velocity, improvement in limiting of inversion/eversion range of motion, re-distribution of the center of plantar pressure between the sole of the foot and the footbed inside the shoe, and maintenance of postural stability as compared to ankle braces.

While various aspects of the present disclosure have been described above, it should be understood that they have been presented by way of example and not limitation. It will be apparent to persons skilled in the relevant art(s) that various changes in form and detail can be made without departing from the spirit and scope of the present disclosure. The present disclosure should not be limited by any of the above described aspects, but should be defined only in accordance with the following claims and their equivalents.

In addition, it should be understood that the figures, which highlight the structure, methodology, functionality and advantages of the present disclosure, are presented as examples only. The present disclosure is sufficiently flexible and configurable, such that it may be implemented in ways other than that shown in the accompanying figures.

Further, the purpose of the foregoing Abstract is to enable the U.S. Patent and Trademark Office and the public generally and especially the scientists, engineers and practitioners in the relevant art(s) who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection the nature and essence of this technical disclosure. The Abstract is not intended to be limiting as to the scope of the present invention in any way.

BIBLIOGRAPHY

1. Sawicki, G S, Ferris, D P. Powered ankle exoskeletons reveal the metabolic cost of plantar flexor mechanical work during walking with longer steps at constant step frequency. The Journal of Experimental Biology; 212: 21-31. 20092. Sawicki, G S, Lewis, C L, Ferris, D P. It pays to have a spring in your step. Exercise Sport Science Review; Vol. 37, No. 3: 130-138. 2009.3. Ferris, D P, Sawicki, G S, Daley, M A. A physiologist's perspective on robotic exoskeletons for human locomotion. International Journal of Humanoid Robotics; Vol. 4, No. 3: 507-528. 20074. Cain S M, Gordon K E, Ferris D P. Locomotor adaptation to a powered ankle-foot orthosis depends on control method. Journal of Neuroeng Rehabil. 2007 Dec. 21; 4:48.5. Gordon, K E, Sawicki G S, Ferris, D P. Mechanical performance of artificial pneumatic muscles to power an ankle-foot orthosis. Journal of Biomechanics 39: 1832-1841. 2006