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:
Aug. 24, 1982
Filed:
Sep. 08, 1978
Applicant:
Inventors:
Ottmar Leuchs, Hannover-Bothfeld, DE;
Hans-Jurgen Kloppner, Langenhagen, DE;
Otto Uhlmann, Burgdorf, DE;
Assignee:
Kabel und Metallwerke Gutehoffnungshutte AG, Hanover, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B22D / ; B28B / ;
U.S. Cl.
CPC ...
295274 ; 2641 / ; 2641 / ; 264171 ; 264173 ; 295272 ;
Abstract
Extruded, drawn and coiled copper tubing with wall thickness of 0.7 to 2 mm is soft annealed, straightened and jacketed in an extruder with a blend of polyvinyl chloride, chalk, a plasticizer and other additives for lubrication and stabilization. The jacket has inwardly extending ribs defining channels inbetween to enhance heat insulation.