Patent GB-427642-A (GB)
Title: Improvements in high voltage thermionic discharge devices such as rectifiers
IPC: B65G47/14
Filed: 1933-10-27
Abstract: 427,642. Discharge devices. ALLIBONE, T. E., Senlac, Norman Road, Sale, SMEE, J. F., Green Gables, Gore Lane, Lindow, Alderley Edge, both in Cheshire, INNES, G. S., Victoria Villa, Lossiemouth, Morayshire, and ASSOCIATED ELECTRICAL INDUSTRIES, Ltd., Crown House, Aldwych, London. Oct. 27, 1933, No. 29931. [Class 39 (i)] To facilitate the dismounting of an electrode, a high-voltage thermionic discharge device, such as a rectifier or a thermionic valve provided with one or more grids, comprises a tubular insulating envelope portion for insulating a tubular end or terminal member, and an electrode support, which at the end remote from the electrode, is secured to a disc or washer adapted to be sealed against a hole in the terminal member, the said support extending radially, at least at first, with the terminal member, and at least one of the electrode supports being bent, actually or in effect, so that the electrode surfaces face one another at the correct distance. A glass, silica, or porcelain container 1, Fig. 1, is sealed, through rings 2, to terminal members 3, which may be sealed through further rings to other insulating containers. An anode 6 is supported through a member 5 from a spider 4 which is secured to a ring 2, while the spiral cathode 7 is carried by a conical plug 8 seated in a conical focusing ring 9, which is secured to a bent tube 11, the lower end of which is secured within a hole 12 in the member 3. A disc 15, sealed against the hole 12 carries, through a tube 14, a spring 13 which is adapted to force the plug 8 into the ring 9. The sealing of the disc is effected through a ring 16 and a wax, grease or oil known under the Registered Trade Mark "Apiezon." One end of the cathode is connected, through a flexible wire insulated by beads 10, to a terminal 17, and the other end is connected through the tube 11, to the terminal member 3. To remove the cathode, the seal 16 is broken and the disc 15, together with the tube 11 and its contents, can then be withdrawn. In a modification, a straight tube 11, Fig. 2, is secured to a spider 18, and the spring 13 is fixed to the end of an elbow 19 carried by the disc 15. A guide 21 on the tube 11 facilitates the entry and withdrawal of the cathode assembly. A disc 15a carries an elbow 5a, which is secured to the anode support 5 through a flexible member 22, which houses a plunger adapted to be pressed, by means of a spring, against the flat end of the pivoted support 5. The arrangement enables the support 5, 5a to be bent upon removal. A number of tubes may be arranged one upon the other, the cathode of one tube being connected to the anode of the next, and is suitable for use in the Greinacher and Cockroft rectifying systems. The tubes may be continuously evacuated by a pump connected to one of the tubes terminating the column. In another form, the anode support 5<b>, Fig. 5, is secured to a plate 27, and extends through the tube 1 and a stress distributer 31 into the terminal member 3. The cathode, directed upwardly, is secured to an elbow 11<a>, carried by the disc 15. Alternatively, the anode support is bent, or the anode is attached to, or formed on, the side of the support to face the cathode which is directed inwardly and radially. To facilitate reversal of the polarity of the tube, two tubes 11, Fig. 1, capable of acting as anodes, are provided and the cathode assembly can be moved from one tube to the other. Alternatively, both tubes may house a cathode assembly. Each cathode may be energized from a generator which is housed within a stress distributer surrounding the terminal ends ; the generators are driven, and connected together, through shafts of insulating material. The anode support may consist of concentric tubes, through which a cooling liquid is adapted to circulate, the tubes being connected to supply pipes, which are housed within the terminal members and are connected through lengths of rubber hose to an earthed water supply. In a further modification, the cathode assembly is mounted within the tubular anode support 40, Fig. 10, which is fixed to the spider 18 and houses cooling pipes 42, 43. The pipes, together with flexible metal bellows 44, unions 47, impeller 49, and a radiator, formed by a double-walled stress distributer 48, constitute a closed circulating system. The impeller is secured to the cathode generator 36 and the distributer 48 may be provided with suitable guides for the liquid. Alternatively, a separate cooler may be connected to the pipes 42, 43 and mounted so as to have the same potential as that of the associated terminal member.