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:
Apr. 16, 1991
Filed:
Dec. 18, 1989
Hiroshi Takanobu, Mobara, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
The present invention relates to an electron gun retaining a cathode and a plurality of electrodes with a pair of bead glasses and a method for manufacturing the same, wherein each of the bead glasses are provided with a convex portion at a position where a bead support for an electrode is buried on a side of the electrodes, each of bead bases of a beading apparatus on which the bead glasses are disposed is formed with a concave portion at a position corresponding to the convex portion of the bead glass, the bead glasses disposed on the bead bases are heated and softened, the bead supports for the cathode and the plurality of electrodes are buried and secured in the bead glasses, and the bead glasses each include convex portions on a side opposite to the electrodes. In accordance with the present invention, recesses and projections over the surfaces of the bead glasses on the electrode sides are reduced in size, thereby further increasing a supporting strength of the electrodes, preventing withstand voltage deterioration of the electron gun, and maximizing a yield in a manufacturing process of the electron gun.