Patent ID: 7320589

Claim:
An injection molding apparatus comprising: a hot runner system for supplying a stream of melt, the hot runner system having an upstream melt passage, a pair of downstream melt passages downstream from the upstream melt passage and disposed substantially transverse to the upstream melt passage; and a separate flow rotator disposed at a first junction between the upstream melt passage and the pair of downstream melt passages, wherein the flow rotator is substantially cylindrical and includes: an inlet aligned with the upstream melt passage to receive the melt stream from the upstream melt passage, an inlet passage receiving melt from the inlet and following an arcuate path such that a downstream portion of the inlet passage is substantially perpendicular to the upstream melt passage where the melt stream enters the inlet, and a first outlet passage and a second outlet passage communicating with the inlet passage such that the flow of melt is split into two streams at a second junction between the inlet passage and the outlet passages, wherein each outlet passage has a curved path from the second junction to a respective first and second outlet, wherein the first and second outlets are disposed on opposite sides of the flow rotator, wherein the first and second outlets each communicate with a respective one of the pair of downstream melt passages such that melt flow from the upstream melt passage is substantially equally divided to flow in opposite directions in the pair of downstream melt passages; and a plurality of hot runner nozzles in communication with and downstream from the downstream melt passages.