Abstract: Device comprises an evacuated envelope and a heater-cathode assembly including an electrically-conductive, porous metal body containing electron-emission material and at least two electrically-resistive legs attached directly to spaced positions on the body. Electric current flowing through the legs and body generates heat in the legs, which heat is thermally conducted to the body. The parts are proportioned to reduce radiation losses by minimizing surface area. The structure reduces bulk and mass to permit short heating-up times.
Abstract: An electric discharge lamp includes a structure within the discharge envelope comprising a source of at least one halogen, metal or metal halide to serve as an arc-modifying additive, enclosed in the structure from which it is capable of being released into the discharge envelope upon subsequent treatment, for example on heating or on striking an arc. The structure preferably comprises a hollow carrier body of refractory metal, in which the source of halogen, metal or metal halide is disposed, and may be covered by a closure of porous sintered refractory metal or of fusible metal. The fusible metal may be inert as regards the discharge and may itself affect the emitted radiation characteristics. The structure may constitute one electrode of the lamp, and may also include electron-emissive material. It has the advantage of protecting the additives from the atmosphere and thereby simplifying manufacture of the lamp.
Abstract: An electrode, particularly for use in tungsten inert gas welding, and a method for the production thereof wherein the electrode consists of a thoriated tungsten electrode rod having a bore in the working end thereof with an internal surface roughness formed by electro-errosion, the bore being filled with a mass of an electron emission increasing metal-nonmetal compound which is fuse-sintered in place to form a centrally disposed plug in the working end of the electrode.
Abstract: A first array of spaced wires is in angular contact with a second array of spaced wires so as to from a wire mesh. The first array has a fewer number of wires than the second array.
Abstract: A diode discharge device may include a tubular anode concentrically encircled by and spaced from a tubular cathode electrode with ends intermediate the ends of said anode electrode, and a metal conductive housing having a tubular wall disposed around the cathode electrode with end walls connected to the anode electrode. High energy electron current coupling is through an opening in the housing tubular wall to a portion of the cathode electrode intermediate its ends. Suitable utilization means may be within the anode electrode at positions to be irradiated by electrons emitted from the cathode electrode and transmitted through the anode walls.
Type:
Grant
Filed:
July 24, 1975
Date of Patent:
July 20, 1976
Assignee:
The United States of America as represented by the United States Energy Research and Development Administration
Abstract: A mass for emission electrodes and the like operating at high temperatures, employing a mixture of thorium dioxide and aluminum oxide, which contains tungsten, the thorium dioxide being present from 33-50% by weight, and the aluminum oxide from 4-15%, to which mixture is added 63-35% of tungsten powder, the powdered tungsten preferably being imbedded in a crystalline melt of thorium dioxide and aluminum dioxide, and a method of producing the same.
Abstract: Firing electron emissive compounds of barium tantalate in excess of 1600.degree.C in controlled vacuum conditions removes elemental barium from the compound. The method provides improved fluorescent lamp quality by yielding substantially less end discoloration over the life of the lamps.
Type:
Grant
Filed:
August 13, 1974
Date of Patent:
July 13, 1976
Assignee:
International Telephone and Telegraph Corporation
Abstract: Performance of fast warm up cathodes can be improved by providing a black heat radiating surface on the interior of the cathode cap. A particular material can be nichrome which is a nickel chromium alloy. The cathode cap material can be selected from any of the known cathode nickel alloys. A preferred method for accomplishing the result includes the steps of cladding a selected nickel alloy with the nichrome material and then forming the substantially cup shaped cap with the clad material on the interior thereof. The formed cathode cap is then fired for about 10 minutes or longer in wet dissociated ammonia at a temperature of about 900.degree. to 1300.degree.C to oxidize the available chromium on the surface of the nichrome. This produces an even dark surface thereon which has much higher heat radiating capabilities than the silver looking nickel cathode alloy.
Type:
Grant
Filed:
February 8, 1974
Date of Patent:
May 18, 1976
Assignee:
GTE Sylvania Incorporated
Inventors:
William E. Buescher, Donald R. Kerstetter
Abstract: A fast warm up cathode comprises a substantially cup-shaped top cap and a hollow cylindrical sleeve axially displaced from the top cap. Means are provided for joining the sleeve and the top cap into an integral unit. The means comprise a plurality of individual rod-like members having extremities substantially flat for attachment to the top cap and the sleeve. The plurality of rod-like members are equally spaced about the periphery of the sleeve and the top cap.
Abstract: An X-ray tube including a tubular envelope having therein two cathode filaments operatively disposed in spaced relationship with an anode target surface, one filament being made of a material suitable for low current operation and the other filament being made of a material suitable for high current operation of the X-ray tube.
Type:
Grant
Filed:
January 3, 1975
Date of Patent:
March 23, 1976
Assignee:
The Machlett Laboratories, Inc.
Inventors:
William P. Holland, Capleton I. Swanson, Jacob A. Randmer
Abstract: A thermionic emitter for apparatus such as electron microscopes, scanning electron microscopes, and high power vacuum tubes which require a source of electrons formed from lanthanum strontium vanadate which is prepared from the compounds La.sub.(1.sub.-x) Sr.sub.(x) VO.sub.3, where x is the fraction of strontium (Sr) incorporated into LaVO.sub.3. The value of x lies between 0.1 and 0.4.
Abstract: The present invention relates to an electronic tube with cylindrical electrodes. In tubes of this kind, where the cathode generally consisting of a wire mesh 1, the space located within same is tightly coupled with the other inter-electrode spaces of the tube. The invention, in order to avert parasitic resonances at the harmonics closest to the operating frequency, which can occur in said space in operation, provides for the arrangement in said space of a certain number of metal sleeves 8, 9 and 10 coaxial with the electrodes, constituting low-inductance coaxial line sections.Application to high-power, short-wave (20 MHz) triodes for transmitting applications.
Abstract: An electron emissive material of the formula (Y.sub.1.sub.-x EU.sub.x)B.sub.6 having the calcium hexaboride type crystal structure can easily produce hexaborides of the single phase. These borides have a number of merits such as small work function, high mechanical properties and low vapor pressure, and they are far more excellent than prior-art materials when used in a thermionic emission cathode and a field emission type cold cathode.