US 4,810,184 AGranted

Injection molding system having manifold with side mounted nozzles

AssigneeMold-Masters Limited

InventorsJobst U. Gellert, Harald H. Schmidt

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Abstract

This invention relates to an injection molding system having a number of nozzles conveying melt from an elongated manifold to a common cavity. In the preferred embodiment, each heated nozzle has a melt channel which is offset from a central valve pin bore for conveying the melt to the gate. The melt channel extends through a side portion of the nozzle which is bolted to the side surface of the manifold. The bolts provide a seal against leakage of the pressurized melt, while at the same time allow slight lateral movement between the manifold and the nozzle. This provides for thermal expansion of the manifold relative to the nozzle which is accurately located in a well in the core. The system is used for large cavities which require large flow volumes and avoids the difficulty of accurate machining of the large molds to provide sealing.

Claims11

Dependent claims

In a multi-gate injection molding apparatus having an elongated manifold and a plurality of heated nozzles, the manifold having a longitudinal melt bore extending from an inlet to a plurality of outlet bores, each outlet bore leading to an outlet on a side surface of the manifold, each nozzle being located in a well in a core and having a forward and a rear end with a melt channel extending to a central gate leading to a common cavity, the improvement wherein;

each nozzle has a side portion extending to a face which projects sidewards from the well adjacent the rear end,
the melt channel of each nozzle has a lateral portion and a generally longitudinal portion, laterally offset from a central axis of the nozzle the lateral portion extending from an inlet on the face of the side portion around a smoothly curved bend to the longitudinal portion, the longitudinal portion leading to the gate adjacent the forward end, and
each nozzle is secured to the manifold with the face of the side portion abutting against a side surface of the manifold with the melt channel inlet in alignment with a respective outlet from the manifold, with provision for slight lateral movement therebetween to provide for thermal expansion of the manifold.

Dependencies are inferred from the claim text.