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:
Oct. 26, 1982
Filed:
Mar. 24, 1980
Harold E St Louis, Midland, MI (US);
Walter A Trumbull, Midland, MI (US);
The Dow Chemical Company, Midland, MI (US);
Abstract
An easily-movable plug seal that is susceptible to quick and ready longitudinal adjustment in the central, lengthwise bore of an internally differentially heated (or cooled) extruder screw for sequentially diverse and distinct heat controlled zones within the extruder barrel is comprised of at least a single, cup-like member that is adequately flexible and supple to be flared laterally outwardly and urged into tight wall contact to make a sealing engagement against the internal screw bore wall upon pressurization of the interior of the plug seal member by the heat transfer fluid being passed into and applied within the screw.