GB357590A - Improvements in or relating to electrical glow discharge devices - Google Patents

Abstract

357,590. Discharge lamps. ELECTRICAL RESEARCH PRODUCTS, Inc., 195, Broadway, New York, U.S.A.-(Assignees of Weinhart, H. W. ; 52, Georgian Court, Elizabeth, New Jersey, U.S.A.) June 25, 1930, No. 19359. Convention date, June 26, 1929. [Class 39 (i).] In a lamp in which a gas discharge takes place near or over the cathode, the discharge is confined to a small portion of the cathode, the temperature of which is controlled by a cooling medium such as water. As shown, the cathode 3 is of cylindrical shape closed at one end and flattened or formed with a plane surface 5 which is surrounded by a rectangular frame 10 of lavite, the remainder of the cathode being covered by an insulating cement 11, such as powdered quartz and sodium silicate. The cathode is sealed into a stem 2 provided with a stopper 16 carrying tubes 17 for the circulation of a cooling medium. The anode 6 is fork-shaped and is mounted parallel with the plane surface 5, the tines of the fork lying in planes along the edges of that surface ; or the anode may consist of a rectangular frame. The anode is supported from the stem 2 by conductors 8 enclosed in glass sleeves. A mica. disc 15 separates the electrodes from the portion of the envelope containing the leads, and prevents undesired discharges. The cathode is of copper plated on its active surface 5 with nickel or beryllium to prevent sputtering. The envelope is provided wth a spherical portion 1 through which the glow is viewed. With this construction sputtered material will be deposited on the cylindrical portion of the bulb. The filling may be neon or argon or both, with or without a small percentage of nitrogen, hydrogen, carbon dioxide or water vapour to reduce the operating voltage.