US 6,005,347 AGranted

Cathode for a magnetron having primary and secondary electron emitters

AssigneeLG Electronics Inc.

InventorJong-Soo Lee

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Abstract

An improved magnetron which is capable of elongating the life span of the magnetron, reducing the fabrication cost, and enhancing the performance of the system without using a filament in the conventional art, which includes a center lead, an upper end shield engaged to an upper portion of the center lead for preventing thermal electrons from being escaped, a plate-type primary cathode arranged below the upper end shield and fixed to one side of the supporting layer surrounding the center lead, a cylindrical secondary cathode having an elongating slit formed in an outer circumferential surface thereof, through which slit a part of the plate-type primary cathode is outwardly extended beyond the outer circumferential surface of the cylindrical secondary cathode, and a lower end shield engaged to the lower portion of the secondary cathode.

Claims7

Dependent claims

A cathode for a magnetron, comprising:

a center lead;
an upper end shield engaging a portion of the center lead and electrically connected to the center lead;
a plate-type primary cathode fixed to the center by a supporting layer surrounding the center lead and electrically connected to the center lead;
a cylindrical secondary cathode having a slit, and through the slit an end of the plate-type primary cathode is outwardly extended beyond an outer surface of the cylindrical secondary cathode;
and
a lower end shield engaged to a portion of the cylindrical secondary cathode and electrically connected to the cylindrical secondary cathode,
whereby a small amount of electrons is radiated from the end of the plate-type primary cathode when a voltage is supplied to the center lead, and the electrons collide with the outer surface of the cylindrical secondary cathode, and thus a large amount of electrons is radiated from the outer surface of the cylindrical secondary cathode.

4 more elements

Dependencies are inferred from the claim text.