Abstract: A sprue bar nozzle assembly for controlling flow of melt through conduits of a mold assembly for injection molding comprises a sprue bar extension and nozzle, the sprue bar extension comprising means for adjusting the overall length of the sprue bar nozzle assembly and the nozzle comprising a nose comprising a seating surface for mating engagement with a mating surface of a mating segment of a melt conveying conduit and a slide valve, an open position of the slide valve permitting melt to flow through the sprue bar nozzle assembly and a closed position preventing melt from flowing through the sprue bar nozzle assembly, the slide valve being biased to a closed position by a biasing means and being driven to the open position by forces applied to the nose of the nozzle as a result of closure of an associated mold assembly.

Abstract: A nozzle controls flow of melt in injection molding equipment by passive actuation with opening and closing of a mold assembly. The nozzle comprises a valve pin having a pin passage therethrough movably supported within a nozzle passage and a contact arm transverse to and extending beyond the nozzle passage, the valve pin sealingly engaging the nozzle passage. Biasing means biases the valve pin to a closed position preventing passage of melt through the nozzle. The contact arm effects movement of the valve pin to an open position when closing of the mold assembly exerts a force on the contact arm to overcome the biasing means. A mold arrangement of plural mold assemblies comprises pairs of nozzles of the invention to control flow of melt through mating conduit segments between an injection unit and at least one mold assembly, the nozzles arranged and configured for seating engagement with abutment of the conduit segments.

Abstract: A molding tool comprises a mold component having a body, a molding surface thereon, and at least one passage internal to the body for conducting a heat transfer fluid from an inlet thereto to an outlet therefrom, the passage comprising a roof spaced from and located proximate the molding surface, a floor spaced from the roof and located farther from the molding surface than the roof, the roof and floor being joined to define a passage cross section, wherein the roof extends within the tooling body so as to substantially conform in size and shape to one or more contours of the molding surface and at least one of the area of the passage cross section and the offset distance of the passage from the molding surface varies between the inlet and outlet. Advantageously, the passage comprises at least one support pillar to constrain deflection of the molding surface during molding.