Footwear including a self-adjusting midsole

Abstract

An article of footwear including an outsole having a plurality of first traction members extending from the outsole and defining a plurality of openings. A plurality of second traction members extend through the openings in the outsole and are configured to move between an extended position, where the second traction members are fully extended in the openings, and a retracted position, where the second traction members are at least partially retracted within the openings. A compressible member is positioned adjacent to the plurality of second traction members and is configured to compress when the second traction members move to the retracted position.

1 . An article of footwear comprising:
 an outsole including a plurality of first traction members extending from said outsole, said outsole defining a plurality of openings;   a plurality of second traction members extending through said openings in said outsole, said second traction members configured to move between an extended position, wherein said second traction members are fully extended in said openings, and a retracted position, wherein said second traction members are at least partially retracted within said openings; and   a compressible member positioned adjacent to said plurality of second traction members and configured to compress when said second traction members move to said retracted position.   
     
     
         2 . The article of footwear of  claim 1 , further comprising an adjustment member including said plurality of second traction members, said plurality of second traction members extending from said adjustment member. 
     
     
         3 . The article of footwear of  claim 2 , wherein said plurality of second traction members are integrally formed with said adjustment member. 
     
     
         4 . The article of footwear of  claim 2 , wherein an upper surface of said outsole defines a recess for receiving said adjustment member so that an upper surface of said adjustment member and said upper surface of said outsole are substantially flush when said adjustment member is inserted in said recess. 
     
     
         5 . The article of footwear of  claim 1 , wherein said plurality of first traction members and said plurality of said second traction members are adjacent to each other. 
     
     
         6 . The article of footwear of  claim 1 , wherein said plurality of first traction members are positioned on an outer portion of said outsole and said openings are located at an inner portion of said outsole so that said plurality of second traction members are at least partially surrounded by said plurality of first traction members when said plurality of second traction members extend through said openings. 
     
     
         7 . The article of footwear of  claim 1 , wherein said plurality of first traction members are integrally formed with said outsole. 
     
     
         8 . The article of footwear of  claim 1 , wherein said outsole is made of an abrasion resistant material. 
     
     
         9 . The article of footwear of  claim 1 , wherein said compressible member is made of a material having a first hardness value and said outsole is made of a material having a second hardness value, wherein said second hardness value is greater than said first hardness value. 
     
     
         10 . The article of footwear of  claim 1 , wherein at least one of said compressible member and said outsole is made of a foam material. 
     
     
         11 . A article of footwear comprising:
 an outsole including traction means located on a perimeter of said outsole for providing traction on an underlying surface, and a plurality of openings on a central portion of said outsole;   a plurality of adjustable lugs extending through and movable within said openings; and   adjustment means operatively connected to said adjustable lugs for extending or retracting said lugs based on the hardness of the underlying surface.   
     
     
         12 . The article of footwear of  claim 11 , wherein said adjustment means is made of a material having a first hardness value and said outsole is made of a material having a second hardness value, wherein said second hardness value is greater than said first hardness value. 
     
     
         13 . The article of footwear of  claim 11 , wherein at least one of said adjustment means and said outsole is made of a foam material. 
     
     
         14 . The article of footwear of  claim 11 , wherein said outsole is made of an abrasion resistant material. 
     
     
         15 . An article of footwear comprising:
 an outsole including a plurality of fixed lugs integrally formed on at least a portion of a perimeter of a first side of said outsole, said outsole defining a plurality of openings located at least partially within said plurality of lugs;   a plurality of adjustable lugs extending through said openings, said adjustable lugs being movable between an extended position and a retracted position; and   a compressible member positioned adjacent to said plurality of adjustable lugs on a second, opposing side of said outsole,   said plurality of adjustable lugs being in said extended position when said compressible member is not compressed, and said adjustable lugs being in a retracted position when said compressible member is compressed.   
     
     
         16 . The article of footwear of  claim 15 , wherein said outsole is made of an abrasion resistant material. 
     
     
         17 . The article of footwear of  claim 15 , wherein said compressible member is made of a material having a first hardness value and said outsole is made of a material having a second hardness value, wherein said second hardness value is greater than said first hardness value. 
     
     
         18 . The article of footwear of  claim 15 , wherein at least one of said compressible member and said outsole is made of a foam material. 
     
     
         19 . The article of footwear of  claim 15 , wherein said fixed lugs and said adjustable lugs are made of different materials.