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:
Jan. 05, 1993
Filed:
Oct. 30, 1990
Toshio Kawaguchi, Yokohama, JP;
Akira Kousaka, Yokohama, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
In a microwave oven magnetron, a first metal cylinder and a ring-like permanent magnet are provided on a magnetron body. Second and third metal cylinders are coaxially arranged in the first metal cylinder so that choking grooves for choking second and fourth harmonic waves are formed between the first and second metal cylinders and the second and third metal cylinders. A ferromagnetic cylinder made of iron or iron alloy is arranged around the first metal cylinder. Thus, a magnetic flux supplied from the permanent magnet into a space inside of the second metal cylinder have axial components which are greater than or equal to 400 gauss in over half the inner space.