GB641481A - Improvements in or relating to the manufacture of electric discharge tubes - Google Patents

Abstract

641,481. Making electric discharge tubes &c. NAAMLOOZE VENNOOTSCHAP PHILIPS' GLOEILAMPENFABRIEKEN. Aug. 8, 1947, Nos. 21912 and 21913. Convention dates, Jan. 16, 1946, and June 19, 1946. [Class 83 (ii)] In a method of making electric discharge tubes, a plurality of conductors formed in one piece from a metal sheet are sealed in insulating material and subsequently insulated from each other by removing the interconnecting metal portions. In an example the metal tags 21, Fig. 2, are sealed between a glass cylinder 26, Fig. 4A, and bulb wall 29 after the electrode system 30 has been connected by wires 31. The uniting strip 24 is then removed to leave the tags 21 insulated from one another. Two or more tags 32 may be bent and welded to an exhaust tube disc 27. In another example the tags 45, Fig. 6, are cut radially from one piece, bent to the required shape and sealed between the glass cylinder 52, Fig. 7, and bulb 57, the raised portions 49 being subsequently ground off to leave the tags 45 and bottom plate 68 insulated from one another, the bent parts 46 serving as contact members. The strips 45 may be bimetallic consisting for example of outer plates of ferro-chromium or other metal which readily adheres to glass and of a central plate of copper or other metal having a high electric conductivity. In a further example the removable strip may carry integral electrodes attached thereto by tags, the electrodes being bent into cylindrical cupped or other shapes, and in another example, tags on the end of a cylinder are sealed in an insulator and then severed from the cylinder which may form the wall of a discharge tube.