A nozzle in an injection molding machine allows for smooth, blended melt flow into a mold cavity. In one example, this is accomplished through use of a nozzle having a nozzle body with a nozzle melt channel in fluid communication with a manifold melt channel and a nozzle tip. The nozzle tip includes a first melt channel in fluid communication with the nozzle melt channel and a plurality of release melt channels between the first melt channel and an annular melt channel. The annular melt channel is formed between a retaining device and the nozzle tip. The annular melt channel includes a decompression chamber in fluid communication with respective ones of the release melt channels and a compression chamber between the decompression chamber and a mold. A pressure difference formed between the respective release melt channels and the decompression chamber and between the decompression chamber and the compression chamber blends the molten material to even and balance flow into the mold cavity.

An injection molding apparatus including an injection manifold having a manifold melt channel, a mold plate having a mold bore, and a hot runner nozzle located in the mold bore and having a nozzle melt channel. A mold insert including a melt channel includes an upper end adjacent the nozzle, a first outer surface adjacent the upper end, and a lower portion including a second outer surface, wherein the second outer surface is in sealing contact with an inner surface of the mold plate. A mold gate insert retainer includes an inner surface surrounding the first outer surface of the mold gate insert and a threaded outer surface for mating with a threaded inner surface of the nozzle. The first outer surface of the mold gate insert and the inner surface of the mold gate insert retainer are non-threaded. A lower end surface of the mold gate insert may form a wall of the mold cavity and may be angled.

A valve-gated nozzle in an injection molding machine allows for smooth, blended melt flow into a mold cavity. In one example, this is accomplished through use of a valve-gated nozzle having a nozzle body with a nozzle melt channel in fluid communication with a manifold melt channel and a nozzle tip. The nozzle tip includes a first melt channel in fluid communication with the nozzle melt channel and a plurality of release melt channels between the first melt channel and an annular melt channel. The annular melt channel is formed between a retaining device and the nozzle tip. The annular melt channel includes a decompression chamber in fluid communication with respective ones of the release melt channels and a compression chamber between the decompression chamber and a mold. A pressure difference formed between the respective release melt channels and the decompression chamber and between the decompression chamber and the compression chamber blends the molten material to even and balance flow into the mold cavity.

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.

A nozzle for an injection molding machine is disclosed that allows for smooth, blended melt flow into a mold cavity. The nozzle includes a nozzle body with a nozzle melt channel in fluid communication with a manifold melt channel and a nozzle tip. The nozzle tip includes a first melt channel in fluid communication with the nozzle melt channel and a plurality of second melt channels between the first melt channel and an annular melt channel. The annular melt channel is formed between a sealing device and the nozzle tip.