Heated nozzle for injection molding apparatus
US4557685A · kind A · utility
Inventor
Key dates
| Filing date | Aug 20, 1984 |
| Grant date | Dec 10, 1985 |
| Priority date | — |
| Expiry date | Aug 20, 2004 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49096
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
This invention relates to an improved heated nozzle for injection molding and an improved method of manufacturing it. The nozzle has an elongated body with a melt bore extending generally centrally through it. The cylindrical outer surface of the body has a variable pitched spiral channel extending around it along its length. A helical electric heating element is embedded in the channel to form an integral structure by which the temperature of the hot melt can be maintained within a narrow range as it flows through the bore. The nozzle is manufactured by forming the body with the channel and bore either by investment casting or machining. The heating element is wound in the channel and a bead of nickel brazing paste is run along the top of it. The nozzle is then heated in a vacuum furnace to braze the heating element in the channel. The highly conductive nickel completely covers the heating element and is fused to both the heating element and the walls of the channel. Thus, a low cost integral nozzle is provided which during use efficiently dissipates heat from the element to prolong its effective life, and applies the heat uniformly along the melt bore.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.