Shoe sole construction with wave cushion

Abstract

Implementations disclosed herein provide for shoes including one or more wave cushions that provide temporary storage of the shoes’ impact energy with the ground and return of a portion of that energy to enhance a runner’s running economy. The wave cushions may include a pair of foundation layers, each with an engagement surface and a sinusoidal sectional profile. The sinusoidal sectional profiles are phase offset, and the elastic membrane is oriented between the engagement surfaces. The engagement surfaces together act as alternating matched pairs of actuators and cavities. Each actuator stretches a portion of the elastic membrane into a cavity when a runner’s weight is applied, converting the runner’s kinetic energy to potential energy stored in the stretched and deformed elastic membrane. As the runner’s weight is removed, the elastic membrane springs back into a substantially planar orientation, transferring the stored potential energy back to the runner as kinetic energy.

What is claimed is: 
     
         1 . A sole construction for a shoe comprising:
 a first foundation layer with a first engagement surface having a first sinusoidal sectional profile;   a second foundation layer with a second engagement surface having a second sinusoidal sectional profile, the second engagement surface facing the first engagement surface, wherein the second sinusoidal sectional profile is phase offset from the first sinusoidal sectional profile by a half of a period (π); and   an elastic membrane oriented between the first engagement surface and the second engagement surface, wherein the elastic membrane is to store potential energy when compressed between the first foundation layer and the second foundation layer, and wherein the elastic membrane is to release kinetic energy when permitted to expand the first foundation layer away from the second foundation layer.   
     
     
         2 . The sole construction of  claim 1 , wherein the first foundation layer, the second foundation layer, and the elastic membrane in combination form a wave cushion, wherein the sole construction further comprises:
 a cushioning and support layer, wherein the wave cushion is oriented within an aperture in the cushioning and support layer.   
     
     
         3 . The sole construction of  claim 2 , further comprising:
 a ground engagement layer applied over a lower surface of the cushioning and support layer.   
     
     
         4 . The sole construction of  claim 2 , wherein the wave cushion underlies one or more of a heel region, a midfoot region, a forefoot region, and a toe region of the shoe. 
     
     
         5 . The sole construction of  claim 2 , wherein the wave cushion is a cassette removable from the aperture in the cushioning and support layer. 
     
     
         6 . The sole construction of  claim 5 , wherein the aperture is accessed from a top side of the cushioning and support layer. 
     
     
         7 . The sole construction of  claim 6 , wherein the elastic membrane includes an outwardly extended flange that is secured to the cushioning and support layer and suspends the wave cushion within the aperture. 
     
     
         8 . The sole construction of  claim 1 , wherein the foundation layers are three-dimensional. 
     
     
         9 . The sole construction of  claim 1 , wherein the foundation layers are two-dimensional and oriented with the sinusoidal sectional profiles running anterior to posterior. 
     
     
         10 . The sole construction of  claim 1 , wherein the foundation layers are two-dimensional and oriented with the first and the second sinusoidal sectional profiles running medial to lateral. 
     
     
         11 . The sole construction of  claim 1 , wherein one of the foundation layers includes ground-engaging features. 
     
     
         12 . The sole construction of  claim 1 , wherein the elastic membrane is pretentioned between the foundation layers. 
     
     
         13 . The sole construction of  claim 1 , wherein a majority of the elastic membrane is stretched and deformed to store the potential energy therein. 
     
     
         14 . The sole construction of  claim 1 , wherein the elastic membrane includes a locking feature at its ends secured to one or both of the first foundation layer and the second foundation layer. 
     
     
         15 . The sole construction of  claim 14 , wherein the locking feature includes T-shaped or L-shaped ends of the elastic membrane. 
     
     
         16 . The sole construction of  claim 14 , wherein the locking feature includes vertical ends of the second foundation layer. 
     
     
         17 . The sole construction of  claim 1 , wherein the elastic membrane is adhered to touchpoints with one or both of the first foundation layer and the second foundation layer. 
     
     
         18 . The sole construction of  claim 1 , wherein the elastic membrane is adhered to endpoints with one or both of the first foundation layer and the second foundation layer. 
     
     
         19 . A method of providing elastic energy return comprising:
 providing a sole construction including:
 a first foundation layer with a first engagement surface having a first sinusoidal sectional profile; 
 a second foundation layer with a second engagement surface having a second sinusoidal sectional profile, the second engagement surface facing the first engagement surface, wherein the second sinusoidal sectional profile is phase offset from the first sinusoidal sectional profile by a half of a period (π); and 
 an elastic membrane oriented between the first engagement surface and the second engagement surface; 
   storing potential energy within the elastic membrane when compressed between the first foundation layer and the second foundation layer; and   releasing kinetic energy from the elastic membrane when it is permitted to expand the first foundation layer away from the second foundation layer.   
     
     
         20 . A shoe comprising:
 a wave cushion including:
 a first foundation layer with a first engagement surface having a first sinusoidal sectional profile; 
 a second foundation layer with a second engagement surface having a second sinusoidal sectional profile, the second engagement surface facing the first engagement surface, wherein the second sinusoidal sectional profile is phase offset from the first sinusoidal sectional profile by a half of a period (π); 
 an elastic membrane oriented between the first engagement surface and the second engagement surface, wherein the elastic membrane is to store potential energy when compressed between the first foundation layer and the second foundation layer, and wherein the elastic membrane is to release kinetic energy when permitted to expand the first foundation layer away from the second foundation layer; 
   a cushioning and support layer, wherein the wave cushion is oriented within an aperture in the cushioning and support layer;   an upper to surround and enclose a user’s foot, wherein the upper is attached to an upper surface of the cushioning and support layer; and   a ground engagement layer applied over a lower surface of the cushioning and support layer.