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:
Sep. 26, 1995

Filed:

May. 27, 1994
Applicant:
Inventor:

Lennart L Carlson, Irvine, CA (US);

Assignee:

Steward Plastics, Inc., Laguna Hills, CA (US);

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04B / ; F24H / ;
U.S. Cl.
CPC ...
392478 ; 392480 ; 392472 ;
Abstract

A helically wound and helically ribbed plastic tubing incorporating an electrically conductive heating wire and an apparatus and method for making the tubing are disclosed. A plastic ribbon is wound about an axis into a tube with one edge of each lap overlapping and heat-bonded to an edge of the preceding lap as the tubing is rotated; a conductive wire is embedded in the ribbon; and a bead is applied and heat-sealed onto the tubing, encapsulating the conductive wire during rotation of the tubing, providing a unitary structure including a conductive wire integral to a flexible tubing having a corrugated crevice-free outside and a smooth inside. Coolant is applied to the tubing for cooling the unitary ribbon, wire and bead tubing and to assist in advancing the tubing along the axis.


Find Patent Forward Citations

Loading…