Abstract: A heating and cooling jacket for the distributor of a injection-molding machine comprises tubular inner and outer sleeves and possibly an intermediate sleeve which defines compartments filled with a high-density particle compacted mass around the cooling tube turns which hug the inner sleeve and electric heater turns which hug the intermediate sleeve.

Abstract: A heating-cartridge assembly has a shell, a first rigid insulating body in the shell having a longitudinally directed end face, a heating conductor imbedded in the body and having a pair of ends, and respective highly conductive and stiff wires imbedded in the body, connected to the ends, and having uninsulated wire ends spaced transversely from each other and projecting longitudinally from the face of the body. A second rigid insulating body independent of the first body and having a respective face is provided with a pair of imbedded and highly conductive tubular sockets having outer ends exposed at the second-body face and inner ends and lying parallel to each other at the same transverse spacing as the projecting uninsulated wire ends. These projecting stiff wires are complementarily and snugly engageable in the tubular sockets with the faces of the two insulating bodies abutting longitudinally. Respective feed conductors are connected to the inner ends of the tubular sockets.

Abstract: An electrical heating cartridge comprises a jacket, preferably of metal, at least one electrical heating coil and a thermocouple element positioned in the jacket which are imbedded with clearance from each other and from the jacket in a specially packed insulating material, wherein the electrical lead conductors of each of the electrical heating coils and the thermocouple element are guided out of a first end piece of the electrical heating cartridge. So that a rapid, controlled, uniform heating of the entire length of the cartridge is attainable, at least one electrical heating coil is directed toward a second end piece opposite to the first end piece of the cartridge and extended over and beyond the thermocouple element until adjacent the second end piece.

Abstract: A cartridge heater includes an inner casing in which a heating element is accommodated. This inner casing is surrounded by an coaxially arranged outer casing of larger diameter so that an annular space is defined between the inner and outer casings. In the space a helical coolant piping is arranged, embedded in a highly heat-conductive substance of granular and/or pulverulent form so as to allow excess heat to be carried away.

Abstract: Elecric cartridge heater having an electric heating conductor in a metallic casing and held on a support of insulating material, each of the ends of the conductor being connected with a lead of lesser electrical resistance than the heating conductor and extending through the open end of the casing the opposite end of which is closed and the conductors being electrically insulated from the heating conductor. The insulating material, preferably magnesium oxide, fills the casing and is present between the casing and the heating conductor and being compacted by diametric reduction or compression of the casing.