04694591 is referenced by 137 patents and cites 30 patents.

An athletic shoe having a midsole subassembly formed of a lower layer and an upper layer, the lower layer having a rear higher density portion terminating short of the front end and integrally bonded with a lower density toe off pad portion into which the toes can sink during toe off. The upper layer extends beneath the heel and forwardly, terminating short of the toe area. This upper layer and the toe off pad have cooperative transverse grooves which are located relative to each other and to vertical flex grooves in the medial and lateral sides of the shoe upper, to enable the shoe to flex in a smooth curve with the foot. This upper layer has overlapping, laterally tapered wedge portions of different density and an integral, upstanding heel stabilizing cup, one portion from each wedge. The outsole has portions of different densities, the heel and ball portions of greater density for wear durability.

Title
Toe off athletic shoe
Application Number
6/723197
Publication Number
4694591
Application Date
April 15, 1985
Publication Date
September 22, 1987
Inventor
Daniel E Norton
Rockford
MI, US
Howard P Banich
Grand Rapids
MI, US
Agent
Price Heneveld Cooper DeWitt & Litton
Assignee
Wolverine World Wide
MI, US
IPC
A43B 13/12
A43B 23/08
A43B 13/18
A43B 5/00
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