Patent ID: 8734309

Claim:
A die set for producing paperboard pressware, comprising: an inner die member having a concave inner face that is opposite an outer peripheral face having a frusto-conical inclined external face and aligned therewith such that a radial line extending from a central longitudinal axis of the inner die member to the outer peripheral face passes through the concave inner face and the frusto-conical inclined external face; and an outer die ring surrounding the inner die member, the outer die ring having a frusto-conical inner face, wherein the frusto-conical inner face of said outer die ring engages against the frusto-conical inclined external face of said inner die member to limit the travel of the outer die ring relative to the inner die member, and wherein the frusto-conical inclined external face of said inner die member and the frusto-conical inner face of said outer die ring are configured to urge said inner die member and said outer die ring toward alignment upon opening of said die set.