Monolithic outsole

Abstract

An outsole construction for a shoe which provides all midsole and outsole functions with a single homogeneous moldable material thorough geometry alone is disclosed. The invention employs cut-out geometry for engineering various characteristics into an outsole of a uniform, monolithic material. Such characteristics are obtained by removing material or reinforcing the material so that it functions as if it had different densities. The invention is based on the principle of minimum sufficient thickness in order to maintain the foot as close to the ground as possible. Energy absorption/cushioning is achieved in the invention by the following features: (1) a series of transverse slots along the lateral border to provide cushion conformability to the lower foot column; (2) an array of compression columns or holes in the heel region to accept the known pressure distributions; (3) an array of small holes in the ball region to add both cushioning and flexibility; (4) a raised heel cup to constrain the heel fat pad expansion during impact and enhance the natural shock absorbing characteristics of the foot; and (5) relief of the rear lateral heel border to dynamically smooth and cushion initial heel strike. The outsole construction of the present invention may be advantageously employed to provide anchor sites for a transverse support sling having straps which are carried over the top of the midfoot and allowed to fan out with attachment to the outsole under the upper and lower columns of the foot. A further embodiment of the invention provides reference anchor points in the outsole for attachment of the shoe upper, thus eliminating the need for a shoe last in manufacturing.