Injection molding nozzle and method
US4771164A · kind A · utility
Inventor
Key dates
| Filing date | Apr 1, 1987 |
| Grant date | Sep 13, 1988 |
| Priority date | — |
| Expiry date | Apr 1, 2007 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C2045/2787
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
This invention relates to an improved injection molding nozzle and a method of making it. The nozzle has an electric heating element integrally vacuum cast in copper in spiral channels set in the outer surface of the tool steel nozzle body. The heating element has a cold terminal at one end which projects out through a hole in a head plate which is rotatable prior to casting to ensure the nozzle has a consistent length of heating element cast in. A sleeve is located over the spiral channel prior to casting to ensure the heating element in the channel is covered with a minimum depth of copper to dissipate the heat from the heating element. The spiral channel can be cut with a varying pitch according to a predetermined profile to provide more heat where there is more heat loss.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.