GB437594A - Improvements in or relating to cathode ray tubes - Google Patents

Abstract

437,594. Cathode - ray tubes. BROADWAY, L. F., 9, Kings Avenue, Ealing, and TEDHAM, W. F., 267, Woolwich Road, Abbey Wood, both in London. March 26, 1934, No. 9474. [Class 39 (i)] The electrodes of an electron gun are arranged one behind another and are each rigidly connected to, and maintained in spaced relation by, parallel metal rods rigidly supported by a collar upon a re-entrant foot or other part of the envelope. Three symmetrically arranged rods 18 of nickel or Staybrite steel are supported by a collar 19 in three sections clamped about the re-entrant tube 11 and are spaced apart by rings 26..28, spot-welded to the rods. Cathode shield 14 is mounted as a sliding fit in a flanged collar 31 secured to a mica ring 32, the ring carrying eyelets 38 spot-welded to the rods 18 to secure the shield 14 to the rods. An accelerator 15, a modulating electrode 16 and a first anode 17 are similarly mounted. In manufacture, a cathode and its heater are mounted on the pinch 12, the rods 18 and the attached electrodes are secured by the collar 19 to the tube 11 and the whole is inserted into and sealed to the tubular part 10 of the envelope. The rings 32 may engage the envelope 10 internally to assist in positioning the electrodes. A second anode may be formed by silvering the envelope. Leads to the electrodes are carried through the pinch 12 or through side walls of the envelope or the rods 18 may serve as leads. The collar 19 may be of corrugated sheet metal. The electrodes 14 .. 17 may be of different diameters.. The Provisional Specification describes also an accelerator electrode having inspection aperture covered with wire mesh for viewing the cathode.