Multicomponent plastics tube injection head - has storage chamber supplied with components each moving along dynamically identical path from extruder to chamber

摘要

Multi-component plastics tube injection head having a frusto-conical injection nozzle at the outlet of storage chamber in which is reciprocated an annular piston has the head provided with two inlets for the components, the inlets being associated with respective annular ducts (II) of identical cross-sections and supplying the components through an annular duct (I) to the chamber. Duct (I) and the ducts (II) are interconnected by a further transverse duct disposed equidistantly between the ducts which communicate with the transverse duct by further annular ducts. Symmetrical arrangement of component supply passages dispenses with correction of flow characteristics of the components. Intermixing and random movement of components is prevented.