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.

Date of Patent:
Oct. 31, 1995

Filed:

Apr. 13, 1993
Applicant:
Inventor:

Robert W Beckwith, Cummaquid, MA (US);

Assignee:

Sencorp Systems, Inc., Hyannis, MA (US);

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B29C / ;
U.S. Cl.
CPC ...
425141 ; 264 406 ; 425144 ; 4253781 ;
Abstract

Apparatus for extruding thermoplastic material includes an extruder having inner and outer die lips adjacent an outlet end of the extruder for transporting an annular stream of thermoplastic material therethrough. The outer die lips are divided into a plurality of circumferential sectors. Each sector includes a passage for circulating heated oil for controlling the viscosity of the thermoplastic material being extruded. The temperature and flow of the heated oil flowing through each sector may be varied according to the required thickness of the product being extruded adjacent that sector. A ring-shaped channel carries the heated oil around the die lips for circulation into the individual sectors.


Find Patent Forward Citations

Loading…