The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 30, 1976
Filed:
Mar. 04, 1975
Alan I Frank, Exton, PA (US);
Other;
Abstract
Molding apparatus for forming an article out of heat-softenable polymeric material, the molding apparatus comprising a mold including a mold cavity and a core insertable into said cavity to define a molding space of the configuration desired in a molded product for receiving the heat-softenable polymeric material, the core being made of heat-conducting material, means, normally including a steam chest in thermoconductive relationship to the mold, for heating the mold, means for admitting into the molding space heat-softenable polymeric material for forming the article and means for conducting steam from the steam chest into the mold cavity to aid in forming expanding and the heat-softenable polymeric material into an article having the shape of the molding space, the last mentioned means comprising at least one duct having a cross-sectional area not greater than 0.001 squre inch, preferably 0.0006 square inch or less, extending radially through the heat-conducting material of the core in which moisture in the steam being conducted into the mold cavity is vaporized. For optimum results a plurality of such ducts each having a cross-sectional area not greater than 0.001 square inch are provided which radiate from the mold axis. The means for heating the core may comprise means for conducting steam into contact with the mold, and some of the steam used to heat the mold may be conducted into the molding space to aid in forming the heat-softenable polymeric material into an article having the shape of the molding space. When forming a cup-shaped article the mold has a cup-shaped mold cavity for receiving the heat-softenable polymeric material and the core is comprised of heat conducting material in particular at the portion thereof where the bottom of the cup-shaped article is formed where the temperature is maximum, and in such case the means for conducting steam into the mold cavity may include valve means at the portion of the mold where the bottom of the cup-shaped article is formed and duct means as above defined extending through the heat conducting material of the core at the portion of the mold where the bottom of the cup-shaped article is formed.