US Patent 6925732 Footwear with separated upper and sole structure

The invention is an article of footwear with an upper and a sole structure. The primary components of the sole structure are a midsole and a frame element. The midsole is connected to the upper in a forefoot region of the footwear, but is unconnected to the upper in a rearfoot region of the footwear. The frame element is structured to extend onto a heel portion of the upper and around the heel portion to thereby stabilize the heel portion. The frame element may serve as a spring that provides cushioning in combination with the midsole. The configuration of the frame element, which extend onto the heel portion of the upper, leaves a lower surface of the upper exposed to permit direct contact with the midsole.