Valve nozzle having a pressure-relief means
US6273706A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 5, 1999 |
| Grant date | Aug 14, 2001 |
| Priority date | — |
| Expiry date | Apr 5, 2019 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29C2045/2879
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A valve-type nozzle (10) is provided for use in hot runner systems through which a plastic material melt is fed under high pressure to a separable and coolable tool having at least one mold cavity (K) for injection-molded items. The nozzle is heatable and comprises at least one needle valve (20) supported by sliding guides (28, 38), the arrangement being such that the melt, which is fed trough a material pipe (14), passes around at least a lower section (22) of the needle valve (20). The nozzle (10) further comprises, in an antechamber (30) upstream of the mold cavity (K), at least one outlet (18) adapted to receive a closely fitting needle end (24). The needle valve (20) includes in its lower section (22), upstream of the needle end, a pressure-relief arrangement that is in direct flow-connection with the antechamber (30). The pressure-relief arrangement comprises, in a guide piece (40), at least one branch-off bore (32; 34) that runs radially at an angle of 90.degree. to the longitudinal direction (L) of the needle valve (10).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.