Method and apparatus for injection molding of multilayer preforms
US4990301A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 25, 1989 |
| Grant date | Feb 5, 1991 |
| Priority date | — |
| Expiry date | Jan 25, 2009 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29K2105/253
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A method of and apparatus for forming multiple layer preforms wherein the various layers may be varied as to number, material, thickness and position in the preform by controlling the injection of the specific materials as to timing, quantity and rate of delivery. Most specifically, a featured aspect is the ability to simultaneously deliver to an injection nozzle and through such injection nozzle into a preform mold cavity two or more molten plastic materials simultaneously. This is possible by way of a multiple gate nozzle and a plurality of separately operable metering pots all controlled by way of a timing device. The timing device may also control the rate of the dispensing an individual material from each of the metering pots.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.