Foam filled tire

A method for preparing a pneumatic rubber tire having its internal cavity filled with a closed cellular foam rubber covered by and contained within said tire cavity with a non-foamed rubber layer, which comprises:

• (A) partially filling the cavity of a previously molded and cured rubber tire with an uncured foamable rubber (e.g. partially filling said cavity with a plurality of layers of said foamable rubber);
• (B) fitting an uncured non-foamable rubber layer on the radially innermost surface of said uncured foamable rubber and within said partially filled cured tire cavity to form a first assembly of said cured tire, uncured foamable rubber and uncured non-foamable rubber layer;
• (C) fitting said first assembly onto a cylindrical curing metal sleeve to close said cured tire cavity which contains said foamable rubber and said non-foamable rubber layer with a air space between said cylindrical metal rim and said non-foamable rubber layer to form a second assembly thereof;
• (D). heating the combination of said assemblies to elevated temperature to cause:
• (1) said foamable rubber to expand by forming a closed cellular structure, and to thereby:
• (a) press said non-foamable rubber layer against and to cure to the inner surface of said cured rubber tire cavity;
• (b) press said non-foamable rubber layer into said air space between said cylindrical metal curing sleeve and said non-foamable rubber layer and against the surface of said cylindrical curing sleeve;
• and
• (2) co-curing of said foamable rubber and said non-foamable rubber layer in combination with said expanding of said foamable rubber.