Sole Unit for Footwear and Footwear Incorporating Same

Abstract

The present invention discloses a sole unit for shoes, sandals, boots, and other articles of footwear. The sole unit comprises at least one spring unit having at least a top wall and a bottom wall that define an opening to allow the top and bottom walls to converge under force, absorbing energy on impact and releasing energy on rebound. Variations in the longitudinal profile, transverse profile, spring-wall thickness, and spring-wall shape permit control over spring force in response to compression. A spring unit may further comprise one or more dampeners to modify the energy-storing properties of the spring unit. A spring unit may further comprise one or more bumpers that come into contact at predetermined distances when compressing the spring unit, to further modify the dynamic response of the spring under a load.

1 . A shoe having a sole unit comprising a spring unit, wherein
 the spring unit adapted for use in footwear and having at least a top wall and a bottom wall;   an opening disposed between the top and bottom walls to allow the top and bottom walls to converge under force;   the spring unit comprising a first profile for at least a portion of the top and bottom walls that is generally oriented in a longitudinal axis, and a second profile for at least a portion of the top and bottom walls that is generally oriented along an axis transverse to the longitudinal axis;   the first profile providing a plurality of spring rates along the longitudinal axis; and   the second profile providing a plurality of spring rates along the transverse axis.   
   
   
       2 . The sole unit of  claim 1  wherein the first profile generally is converging going from a rearward end of the spring unit toward a frontward end of the spring unit. 
   
   
       3 . The sole unit of  claim 1  wherein the first profile generally is converging going from a frontward end of the spring unit toward a rearward end of the spring unit. 
   
   
       4 . The sole unit of  claim 2  wherein the second profile is generally converging going from a lateral side to a medial side. 
   
   
       5 . The sole unit of  claim 4  wherein there are a plurality of sections of convergence or divergence between the lateral and medial sides of the second profile. 
   
   
       6 . The sole unit of  claim 1  wherein between the lateral and medial sides of the second profile there are a plurality of sections of convergence or divergence. 
   
   
       7 . The sole unit of  claim 1  wherein between the front and rear of the spring unit along the longitudinal axis there are a plurality of sections of convergence or divergence. 
   
   
       8 . The sole unit of  claim 1  wherein along the longitudinal axis, there is a change in the uniformity of the top or bottom walls responsiveness to force due to varying and changing sectional thicknesses throughout the surfaces, together with different material types, hardnesses, and flexibilities the spring unit offers a tuned and structured variety of load resistances, and appropriate directional force management, dependent upon the requirements of the various typical foot-strike and load management requirements. 
   
   
       9 . The sole unit of  claim 1  wherein the angles of the front and rear surfaces, combined with the radii at adjoining bottom and top walls can be adjusted to accommodate to different load, load direction, and energy transitional requirements, according to the particular purpose of the shoe. 
   
   
       10 . The sole unit of  claim 1  further comprising a plurality of spring units, which are placed in any and various areas of the underfoot, in any and various configurations, in order to provide many different options of foot-strike force dissipation and transitions, catering to different requirements of various users. 
   
   
       11 . The sole unit of  claim 1  further comprising a dampener. 
   
   
       12 . The sole unit of  claim 11  or  claim 16  wherein the dampener is associated with at least one surface of the spring unit, so that compression of the spring unit places the dampener under tension, creating a return force applied to the spring unit. 
   
   
       13 . The sole unit of  claim 1  wherein the spring unit is located at a position in the rear lateral area of the heel of the underfoot, or at a position of the foot which makes contact with the ground first, during stepping or foot-strike motion, can have its long surfaces aligned transversely with this axis appropriate to foot-strike patterns typical to linear stepping motion, motion such as while running, or sideways lateral foot strike such as in court sport activity. 
   
   
       14 . The sole unit of  claim 1  wherein the spring unit can be made from any material with spring-like, energy absorbing and energy storing qualities, such as polymers, metals, composites, or any appropriate combinations of these. 
   
   
       15 . The sole unit of  claim 1  wherein the spring unit further comprises at least one bumper to limit travel of opposing walls of the spring unit. 
   
   
       16 . A sole unit comprising at least one spring unit, the spring unit having opposing top and bottom walls, spaced along an axis, the spring unit having a plurality of spring rates along at least a portion of the axis, and a dampener disposed between top and bottom walls. 
   
   
       17 . The sole unit of  claim 16  wherein the dampener is disposed so that the length or elongation of the dampener does not exceed the maximum opening between the surfaces of the spring unit to which it is attached or aligned, thereby coming into tension at the point when the load on the spring unit is released and the forces are returned by the spring unit. 
   
   
       18 . The sole unit of  claim 1  wherein the spring unit has continuous complex curved surfaces, including an upper, outer surface that conforms to the bottom shape of the foot, in the areas where the spring unit is located. 
   
   
       19 . The sole unit of  claim 1  wherein the spring unit has an upper, outer surface that conforms to the bottom shape of the foot includes surfaces that wrap up and around the side surfaces of the foot, in order to better control the foot position during transitional loading due to foot-strike motions in any direction. 
   
   
       20 . A sole unit for footwear comprising a spring unit and a dampener, wherein the dampener is placed under tension when the spring is compressed, creating a return force applied to the spring unit. 
   
   
       21 . A spring unit according to  claim 1  wherein through varying, complex sectional shape and dimension the unit provides different and appropriate resistances and spring rates throughout the length and width of the unit