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US 5,235,737 AGranted
Method of making an injection molding nozzle with a heating element extending outward between adjacent collar portions
OwnerJobst U. Gellertinventor
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OwnerJobst U. Gellertinventor
Estimating the term…
A method of making an injection molding nozzle having an electrical heating element wound in a channel. The heating element has two terminal wires which extend radially outward parallel to each other from either a common end portion or two separate end portions of the heating element. After the heating element is wound in the spiral channel in the nozzle body, forward and rear collar portions are mounted around the nozzle body to form a radial slot or opening between them through which the end portion or portions of the heating element project. A stud portion is mounted to extend radially outward from the slot with a single bore or two parallel bores through which the end portion or portions extend. These components are then brazed together in a vacuum furnace to form a strong integral structure with the end portion or portions of the heating element secured in place. In one embodiment, a spacer portion having two parallel bores is mounted with ceramic paste to the stud portion. The two terminal wires extend out through the bores for connection in a threaded cap to a pair of external lead wires.
In a method of making an injection molding nozzle including the steps of making an elongated steel outer body with a rear end, a forward end, a generally cylindrical outer surface, and a melt bore extending centrally therethrough from the rear end to the forward end, and integrally vacuum brazing an insulated electric heating element in a spiral channel in the outer surface of the body, the heating element having an insulated heating wire extending in an outer casing, the improvement comprising the further steps of:
A method of making an injection molding nozzle as claimed in 3 wherein the radially projecting end portions of the heating element are longitudinally aligned and further including making the forward collar portion and the rearward collar portion whereby the radial opening through which the two end portions of the heating element extend between the forward collar portion and the rearward collar portion is a longitudinally extending slot to receive the longitudinally aligned end portions of the heating element.
Dependencies are inferred from the claim text.