Methods of and apparatus for insulating a conductor with a plastic material
US4512944A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 23, 1983 |
| Grant date | Apr 23, 1985 |
| Priority date | — |
| Expiry date | Jun 23, 2003 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2011/00
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Extruder tooling for directing plastic materials to enclose a conductor (26) being advanced along a path of travel through a core tube (97) and aligned dies includes disc-like flow passages (107, 129) which are disposed concentrically about and perpendicularly to the conductor. This arrangement minimizes conductor tension in a pressure extrusion arrangement by significantly reducing the length of the plastic-to-conductor contact within the extruder. The length and width of each flow passage normal to and along a path of travel are sufficient to provide a uniform distribution of plastic material circumferentially about the conductor and to dissipate stresses which have been induced in the plastic materials. In a tubing arrangement, the length of a cantilevered portion of the core tube is reduced significantly which results in improved concentricity of the plastic material about the conductor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.