ALEXANDRIA, Va., Feb. 24 -- United States Patent no. 12,557,878, issued on Feb. 24, was assigned to Xelero Technology LLC (Hillsborough, N.J.).
"Footwear sole assembly" was invented by Daniel Werremeyer (Hillsborough, N.J.) and Robert Tighe (Easton, Pa.).
According to the abstract* released by the U.S. Patent & Trademark Office: "A footwear sole assembly with upper and lower layers, where the upper layer has a firmer durometer than the lower layer. Upon a user's heel strike, the difference in resilience between the upper and lower layers causes the upper layer to compress the lower layer. Sidewalls in the upper layer are urged toward each other on the heel strike, providing cradling support for the user's heel. The rigidness of the sidewa...