Footwear

A structure to foam part of a shoe, comprising a sealed sole member of elastomeric material providing a plurality of chambers, said chambers being inflatable with a gaseous medium under pressure to a desired initial value, and a permeable elastomeric yieldable outer member encapsulating said sole member, said sole member being permeable, said gaseous medium under pressure in said chambers including a gas other than air, oxygen or nitrogen, said elastomeric material having characteristics of relatively low permeability with respect to said gas to resist diffusion of said gas therethrough from said chambers and of relatively high permeability with respect to the ambient air surrounding said sole member to permit diffusion of said ambient air through said elastomeric material into said chambers to provide a total pressure in each chamber which is the sum of the partial pressure of the gas in each chamber and the partial pressure of the air in each chamber, the diffusion rate of said gas in each chamber being substantially lower than the diffusion rate of nitrogen through said elastomeric material.

Footwear comprising a shoe upper, a sole below and secured to said upper, said sole including a sealed inner member of elastomeric material providing a plurality of chambers, said chambers being inflatable with a gaseous medium under pressure to a desired initial value, and said sole further including an elastomeric yieldable outer member encapsulating said inner member, said inner member having peaks and valleys in its upper and lower surfaces, the upper surface of said outer member being spaced above said peaks, said outer member extending downwardly from its upper surface to fill the space between said upper surface and said peaks and also to fill at least said valleys in said upper surface of said sole member, whereby the downward load of the wearer's foot is transmitted from said upper surface of said outer member through said outer member to the inflated chambers of said sole member.

Footwear comprising a shoe upper, a sole below and secured to said upper, said sole including a sealed inner member of elastomeric material providing a plurality of chambers, said chambers being inflatable with a gaseous medium under pressure to a desired initial value, and said sole further including an elastomeric yieldable outer member encapsulating said inner member, said inner member and outer member constituting a midsole, an outsole secured to the inner side of said outer member, said outer member being a permeable elastomeric foam, said inner member being permeable, a gaseous medium under pressure in said chambers including a gas other than air, oxygen or nitrogen, said elastomeric material having characteristics of relatively low permeability with respect to said gas to resist diffusion of said gas therethrough from said chambers and of relatively high permeability with respect to the ambient air surrounding said sole member to permit diffusion of said ambient air through said elastomeric material into said chambers to provide a total pressure in each chamber which is the sum of the partial pressure of the gas in each chamber and the partial pressure of the air in each chamber, the diffusion rate of said gas in each chamber being substantially lower than the diffusion rate of nitrogen through said elastomeric material.