US Patent 7544056 Valve-gated injection molding nozzle having an annular flow

A valve-gated nozzle for an injection molding machine includes an annular flow channel between downstream portions of a nozzle liner and a sealing and/or retaining device. The nozzle liner includes a first melt channel and one or more second melt channels for communicating a melt stream to the annular melt channel. The annular melt channel is formed between an inner surface of the downstream portion of the sealing and/or retaining device and an outer surface of the downstream portion of the nozzle liner. The annular melt channel may include a groove within at least one of the inner surface of the sealing/retaining device and the outer surface of the nozzle liner, such that the groove is in communication with an outlet of the second melt channel to thereby guide and/or blend the molten material within the annular melt channel to even and balance flow into a mold cavity.