GB633926A - Improvements in and relating to thermionic valves - Google Patents

Abstract

633,926. Thermionic valves. METROPOLITAN-VICKERS ELECTRICAL CO., Ltd. Dec. 30, 1947, No. 34740. Convention date, Dec. 12, 1942. [Class 39 (i)] In a high power thermionic valve the anode 25, 26, Figs. 1, 2, is double walled and is water-cooled, the walls being connected at the upper end by a member 22 and supported, the inner rigidly at 24 and the outer flexibly at 27 at the other end so as to allow for differential thermal expansion of the inner and outer anode walls, an electrically insulating envelope member Q2 surrounding the outer anode wall and the outer anode wall being exposed to the vacuum within the valve. A baffle 28 forces the water to flow longitudinally of the anode. The filaments are attached to support-rods 9 by intermediate threaded members, Figs. 3, 4 (not shown), and the rods 9 are fixed to members 1, 3 by screws 10 ; the cathode leads 1, 2, 3 are water-cooled and the metal ring 5 on which the leads 1, 2, 3 are mounted has water-cooling channels 7, 8. A screen 6<1> prevents particles from the cathode from impinging on the insulator 6. The grid is mounted on metal rings 13, 14 formed with water-cooling channels 15, 16. A screen 18 and ring 20 protects the joint 19 from the grid-cathode high-frequency field, and a screen 21 prevents particles from the cathode from impinging on the insulator Q2. The anode is carried by metal rings 23, 24. The baffle 28 is formed by two half-cylinders clamped together by bands.28a. A baffle construction 32, 36 prevents vapour from the cathode from impinging on the insulator Q3. A vacuum pump (not shown) is attached to the lower end of the device. The seals are made by putty and the insulators Q1, Q2, Q3, are of cast quartz.