Magnetron having a cathode mount with a grooved recess for securely receiving a cathode filament
AssigneesHitachi, Ltd., Hitachi Electronic Devices Co., Ltd.
InventorToshio Ogura
Life of this patent
Estimating the term…
Abstract
A magnetron includes a cathode mount having a directly heated helical cathode filament for emitting thermoelectrons, an upper end shield and a lower end shield disposed so as to support the filament at upper and lower ends thereof, and center and side leads holding the upper and lower end shields respectively. The lower end shield is formed with a recess for housing the lower end of the directly heated helical cathode filament in the upper surface thereof, at least a portion of the inner wall of the recess is sloped, and a groove is formed at the peripheral edge of the bottom of the recess.
Claims11
A magnetron apparatus comprising:
- a directly heated helical filament for emitting thermoelectrons;
- an upper end shield and a lower end shield disposed so as to support said directly heated helical filament at an upper end and a lower end thereof, respectively;
- a center lead passing through said lower end shield and said filament and being fixed to said upper end shield;
- and
- a side lead adjacent to said center lead and fixed to said lower end shield;
- wherein said lower end shield includes an opening through which said center lead passes and a recess for housing and supporting a lower end of said directly heated helical filament, at least an upper portion of an inner wall of said recess of said lower end shield being sloped, and a groove being provided at a peripheral edge of a bottom of said recess of said lower end shield adjacent a lower portion of the inner wall of said recess.
Dependencies are inferred from the claim text.