| 摘要 |
A method of making an electrically insulated terminal (12) in an injection nozzle (10). After the heating element (44) is wound in a spiral channel on the outer surface (36) of the main body portion (14) of the nozzle the rear end (104) projects radially out an opening (80) in the collar portion (16). The casing (102) is stripped from the heating element to expose the resistance wire (112) adjacent the rear end. A steel plug (78) having a central bore (76) therethrough is slipped over the projecting rear end and welded into place in the opening. A steel terminal body (82) is made with a central bore (106) and a threaded front portion (84) to receive an external power lead (118). The casing (102) of the portion of the heating element (104) projecting from the plug and a rear portion (88) of the terminal body (82) are coated with insulating material (92). A protective cap (94) is securely swaged over the coating on the rear portion. The assembled cap and body are slipped over the rear end of the heating element and welded to the matching front face (100) of the plug (78). The exposed resistance wire (112) is welded to the terminal body (82). This structurally secures the terminal body against torque from connecting and disconnecting the external lead and electrically insulates it from the rest of the nozzle, while electrically connecting it to the resistance wire. In an alternate embodiment, the connections are made while integrally brazing the nozzle in a vacuum furnace. |
