Patent ID: 8011118
Filing Date: 2011-09-06
Classification: A43B

Abstract:
1. An article of footwear comprising: an outsole having a bottom surface including a circular tread pattern, the circular tread pattern formed of a plurality of circular treads extending over a forefoot portion of the outsole and a heel portion of the outsole, and the bottom surface of the outsole being made of a material having a first coefficient of sliding friction; a pivot tread positioned substantially at a center of the circular tread pattern, the pivot tread having a generally circular cross-sectional shape, protruding a first distance from the bottom surface of the outsole, and being made of a material having a second coefficient of sliding material; the center of the circular tread pattern being common to all of the plurality of circular treads; the circular tread pattern including a first circular tread having a first radius, the first radius being the smallest radius of any circular tread; the first circular tread comprising a plurality of tread elements disposed around the pivot tread and protruding a second distance from the bottom surface of the outsole, the first distance being approximately equal to the second distance; the tread elements having a generally elongated shape with a radial width and a circumferential thickness, wherein the radial width is greater than the circumferential thickness; the tread elements being made of a deformable material having a third coefficient of sliding friction that is greater than the first coefficient of sliding friction of the bottom surface of the outsole and the second coefficient of sliding friction of the pivot tread; and the circular tread pattern also including a second circular tread having a second radius greater than the first radius.