A resin intrusion prevention structure for preventing resin intrusion into a heater in a shut-off nozzle, the shut-off nozzle including a nozzle body having an injection flow path, through which resin flows, in an axial direction and a shut-off valve configured to open and block the injection flow path. The resin intrusion prevention structure is provided in a vicinity of a sliding exposed portion, which is exposed to an outer circumferential surface of the nozzle body in a sliding portion, and is configured to prevent the resin leaking from the sliding exposed portion from intruding into the heater provided in the shut-off nozzle.

An injection nozzle is attachable to a tip end of a heating cylinder and having an in-nozzle flow path formed therein. The injection nozzle is attached to the heating cylinder by being pressed against the heating cylinder by a nozzle pressing member that is fixed to an end surface of a tip end of the heating cylinder. An outer peripheral surface of the injection nozzle has a sensor hole that is opened at a position contacting the nozzle pressing member, and a temperature sensor is inserted into the sensor hole.

Disclosed herein are novel methods for forming a polymer part including providing an injection molding system with a shut-off nozzle, where the shut-off nozzle includes a main body, a nozzle tip body, a flow path through the main body and the nozzle tip body, a nozzle tip, and a shut-off mechanism. The nozzle tip includes an internal passage and a cooling mechanism. The shut-off mechanism includes a passageway intersecting the flow path at an angle and a pin positioned in the passageway. The method further includes the steps of initiating an injection molding cycle by injecting molten polymer through the shut-off nozzle into a cavity of a mold, actuating the shut-off mechanism to move the pin in the passageway into the intersection of the passageway and flow path, and initiating the cooling mechanism to solidify molten polymer in the nozzle tip to form a solid slug.

A system for achieving high-definition pressure control of manufacturing operations utilizes data from one or more primary sensors, each of which is associated with a relatively high degree of accuracy based on the primary sensor's proximity to material involved in the manufacturing operation, as well as data from one or more secondary sensors, each of which is located more remote from the material involved in the manufacturing operation than the primary sensors. Data from the one or more primary sensors is evaluated to detect errors or trends indicative of primary sensor failure. Suspect or compromised primary sensor data is then disregarded or filtered, using data from the secondary sensors, historical data, or some combination thereof.

An injection molding machine heats an injection nozzle using, as a target temperature, a detected temperature of a synchronization zone, when a detected temperature of the injection nozzle is lower than a nozzle reference temperature. The injection molding machine heats the injection nozzle using a nozzle set temperature as a target temperature, when a detected temperature of the injection nozzle is higher than the nozzle reference temperature.