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, 1995
Filed:
Jan. 22, 1993
Takeyuki Maegawa, Hyogo, JP;
Yoshio Takada, Hyogo, JP;
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
A manufacturing method of an impregnation type cathode for removing emitter material remaining on the porous sintered body pellets, includes steps for impregnating the emitter material into void spaces between the porous sintered body pellets, heating a phosphoric compound in a vessel up to the temperature in a range of about 100.degree. C. to about 300.degree. C., and dipping the impregnated emitter material into the heated phosphoric compound. The manufacturing method of the present invention creates a cathode which operates stably for a long time with high current density because there is no damage caused when the remaining emitter material is removed from the surface of the porous sintered body pellets.