GB590550A - Improvements relating to the mounting of electrode assemblies in electric discharge tubes - Google Patents

Abstract

590,550. Discharge apparatus. FERRANTI, Ltd., CHILCOT, A. L., and BIRTWISTLE, W. July 24, 1943, No. 12090. [Class 39 (i)] [Also in Group XXIII] Rotational displacement of an electrode assembly, for example under angular acceleration within a spinning projectile, is prevented by projections k, Fig. 4, which engage two or more depressions e<1> in the inner wall of the glass envelope a. Longitudinal and transverse displacement are prevented by engagement of upper spacing disc m against a ledge h, and of serrated lower disc o against the envelope wall. Ledge h may be replaced by three protuberances and similar arrangements may be made for lower disc o. Ledge h and depressions e<1> are formed in a two-part mould or by suction on to a single internal mandrel. Instead of the thermionic diode shown in Fig. 4, a cold cathode tube may have its thimble-shaped. cathode l<1>, Fig. 5, provided with rods k<1> which engage at each end depressions el, e<11> in cupshaped glass members t, t<1> which are sealed together at the rims to complete the assembly. A gas filling may be provided. Specifications 573,569, 573,572 and 574,480 are referred to. According to the Provisional Specification, an internal projection on the envelope may engage a depression or key-way in the electrode assembly ; the key-way in either the envelope or the assembly may be a pair of projections close together.