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. 02, 1979
Filed:
Dec. 12, 1977
John C Miller, Piscataway, NJ (US);
Archibald L Burnett, Warren, NJ (US);
Leonard S Scarola, Union, NJ (US);
Union Carbide Corporation, New York, NY (US);
Abstract
The invention provides apparatus for the production of cellular thermoplastic material comprising an extruder having a hollow barrel, screw means mounted in said barrel to advance material therethrough, mixer head means mounted in said barrel and gaseous blowing agent inlet means positioned in said barrel near the upstream end of said mixer head means, said mixer head means having in the surface thereof a plurality of alternate land and groove means, said land means having close clearance with the internal walls of said barrel near the upstream end thereof in the region of said blowing agent inlet means and alternately spaced and close clearance with said walls in the mixing region downstream of said blowing agent inlet means.