Extrusion apparatus for producing a cable
US7377763B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 5, 2006 |
| Grant date | May 27, 2008 |
| Priority date | — |
| Expiry date | Apr 5, 2026 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29K2077/00
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
An extrusion method and apparatus (11) for producing a cable (1, 101) including at least one core (7) comprising at least one transmissive element (2, 40), and at least one pair of coating layers (8, 9) arranged at a radially outer position with the respect of the core (7) are described. The method of the invention includes the simultaneous steps of depositing by co-extrusion at least one coating layer (8) of polymeric material and one coating layer (9) of expanded polymeric material and of maintaining a residual pressure not greater than the external pressure in a substantially annular interspace (21) defined between the coating layers. With respect to the methods of the prior art, the present invention allows to avoid the formation of bubbles at the interface between said at least one coating layer (8) of polymeric material and the coating layer (9) of expanded polymeric material, attaining an optimal adhesion between said layers (8, 9).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.