Process and apparatus for molding structures comprising longitudinally juxtaposed slats
US4961895A · kind A · utility
Inventor
Key dates
| Filing date | Jun 15, 1988 |
| Grant date | Oct 9, 1990 |
| Priority date | — |
| Expiry date | Jun 15, 2008 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2031/719
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Process and apparatus for the manufacture of integral roller door structures of any desired length and width, and comprising longitudinally juxtaposed slats separated by integral hinge formations. Such a structure having slats of any desired length can be produced by a semi continuous moulding process in which a molten plastics material and a foaming agent are injected into a mould, the part of the structure so formed being allowed to solidify before removing the solidified structure partially from the mould, then closing mould about the remaining portion of the structure, thereafter moulding a further part of the structure within the mould onto the remaining portion of the previously moulded part and repeating the cycle as often as required. A product of any desired width, measured transversely to the salts, can be produced by welding, edge-to-edge a plurality of lengths of the product produced by the moulding technique, by means of an apparatus incorporating a heated knife which is advanced along the gap between opposing edge faces of the lengths of moulded structure to be welded, to fuse the material of said opposing faces, and further incorporating an extruder which follows the…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.