An improved heater band for a hot runner injection molding machine. The heater band includes a cylindrical sleeve adapted to be disposed about a nozzle body in combination with a first wire heating element and a second wire heating element. The first wire heating element includes two contact terminals and an intermediate portion therebetween. The intermediate portion of the first wire heating element is disposed within the cylindrical sleeve. The second wire heating element includes two contact terminals and an intermediate portion therebetween. The intermediate portion of the second wire heating element is also disposed within the cylindrical sleeve. The intermediate portions of the heating elements are adjacent to and axially offset from one another within the cylindrical sleeve. The first wire heating element and the second wire heating element can be alternatively connected to an electrical power supply to extend the operational life of the heater band.

A heating cylinder heater includes a plurality of infrared heaters disposed around a heating cylinder in a non-contact manner with respect to the heating cylinder, a heat insulating material provided outside the infrared heaters, and a cover configured to cover the heat insulating material. The cover has two or more opening portions, and a part or all of the two or more opening portions are each provided with an opening-closing device that is configured to open and close the corresponding opening portion.

A heating apparatus (5) in an injection molding apparatus (1000) comprising: a heatable sleeve or jacket (10) comprised of a sheet (14) of highly heat conductive metal material, formable into a heating cylinder (14c) having a central channel (16) receiving a selected nozzle (40), a stabilization ring or cylinder (20) adapted to receive a selected longitudinal portion (DL) of the downstream or distal end (14de) of the heating cylinder (14c) and to engage or mate an inner circumferential surface (20is) with an outer surface (14os) of the heating cylinder.

An improved heater band for a hot runner injection molding machine. The heater band includes a cylindrical sleeve adapted to be disposed about a nozzle body in combination with a first wire heating element and a second wire heating element. The first wire heating element includes two contact terminals and an intermediate portion therebetween. The intermediate portion of the first wire heating element is disposed within the cylindrical sleeve. The second wire heating element includes two contact terminals and an intermediate portion therebetween. The intermediate portion of the second wire heating element is also disposed within the cylindrical sleeve. The intermediate portions of the heating elements are adjacent to and axially offset from one another within the cylindrical sleeve. The first wire heating element and the second wire heating element can be alternatively connected to an electrical power supply to extend the operational life of the heater band.

An injection molding apparatus and an method for the manufacture of moldable articles having an injection manifold, a plurality of hot runner nozzles, a first nozzle heater, a plurality of mold cavities positioned to receive molten material from the plurality of the hot runner nozzles, each mold cavity having at least one mold gate orifice and a mold cavity heater surrounding each mold cavity at least partially and a thermocouple associated with the mold cavity to measure directly or indirectly a temperature generated by the mold cavity heater.

A nozzle heater assembly coupled to a hot runner nozzle includes a heater support made of at least two support segments spaced apart by a gap. A heater element secured to both support segments is configured to limit the gap between the two segments. The nozzle heater assembly to be coupled to a hot runner may also include in other applications a heater support formed of a single piece and configured as a hollow helical tube including at least two axial gaps. A heater element is secured to the helical tube, where the helical tube can be compressed or stretched axially to alter a clamping force generated when the helical tube and the heater are coupled to the hot runner nozzle.