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:
Aug. 11, 1981
Filed:
Nov. 21, 1979
Applicant:
Inventors:
Genichi Goto, Tokyo, JP;
Sadamasa Hanihara, Tokyo, JP;
Assignee:
Nippon Electric Co., Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J / ;
U.S. Cl.
CPC ...
315-35 ; 315-36 ; 315 393 ;
Abstract
In a traveling wave tube device of the type comprising a helix which causes a microwave power to interact with an electron beam and a periodic permanent magnet assembly for focusing the electron beam, there are provided a plurality of annular permanent magnets and a plurality of pole pieces which are alternately disposed between input and output member of the microwave. The permanent magnets and pole pieces define annular recesses and a plurality of troidal metal spring rings are disposed in each recess in thermal contact with the permanent magnets and a carbonaceous coating coated on a pumped enclosure containing the helix.