The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 02, 1980
Filed:
Mar. 30, 1979
Hisashi Ando, Hitachi, JP;
Ko Soeno, Hitachi, JP;
Hiroshi Sakamoto, Hitachi, JP;
Testuo Oyama, Takahagi, JP;
Takao Kawamura, Chiba, JP;
Hiroshi Fukushima, Chiba, JP;
Hitachi, Ltd., , JP;
Abstract
A directly heated cathode for electron tube having a stable electron emission characteristic and a low cut-off voltage is provided. The cathode comprises a base metal of an alloy consisting essentially of 20-30% by weight of tungsten and a trace amount to 0.25% by weight of zirconium, the balance being nickel, binder dots of metallic nickel powders distributed on a flat part at the front side of the base metal, and a layer of thermoelectron emission oxides laid on the flat part at the front side of the base metal. The layer of thermoelectron emission oxides is in direct contact with the flat part through clearances among the binder dots of the metallic nickel powders.