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:
May. 23, 1989
Filed:
Sep. 02, 1987
Applicant:
Inventors:
Yukio Suzuki, Mobara, JP;
Masaharu Kumada, Mobara, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J / ;
U.S. Cl.
CPC ...
3133 / ; 3133 / ;
Abstract
An impregnated cathode which has a portion where no electron emissive material is present on the surface layer of the cathode base body that is to be welded, in order that the cathode base body impregnated with the electron emissive material, a cup and a cathode sleeve can be firmly welded together. The cathode base body which has no electron emissive material on the surface layer is obtained by washing the cathode base body in a solvent which is capable of dissolving the electron emissive material. Using this cathode base body, the impregnated cathode is fabricated.