Fixed-volume trapped rubber molding apparatus

A molding apparatus for subjecting a part to be molded to a predetermined sequence of increased temperatures and pressures, said apparatus comprising:

• a fixed-volume, rigid mold having a die positioned therein, said die having a working surface shaped so as to conform to the configuration of the part to be molded, said mold containing a cured elastomer which, at least in an area adjacent the die, is an integral solid, said elastomer conforming generally to the interior configuration of said mold and being spaced from said working surface a distance sufficient to accommodate the part to be molded, said elastomer having a relatively high coefficient of thermal expansion and a relatively low coefficient of thermal conductivity, at least the integral solid portion of the elastomer having a relatively low modulus of elasticity, said die and the cured elastomer surrounding it occupying one zone of the interior of said mold, a second zone of the interior of said mold containing additional cured elastomer;
• first heating means for selectively heating the die and at least a portion of the cured elastomer in said one zone;
• first cooling means for selectively cooling the die and at least a portion of the cured elastomer in said one zone;
• second heating means independent of said first heating means for selectively heating at least a portion of the additional cured elastomer contained within said second zone;
• second cooling means independent of said first cooling means for selectively cooling at least a portion of the additional cured elastomer contained within said second zone;
• whereby the part to be molded can be selectively and independently subjected to increases and decreases in temperature and pressure by control of said first and second heating and cooling means.