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:
Nov. 22, 1977
Filed:
Jan. 12, 1977
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., , JA;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H05B / ; H02H / ;
U.S. Cl.
CPC ...
315107 ; 328-9 ;
Abstract
An electron producing apparatus of the field emission type wherein instantaneous values of an emitted current are sequentially measured to store a relative minimum value of the emitted current which is obtained in such a manner that one instantaneous value which is stored is then replaced by another instantaneous value which is even smaller in magnitude than the previously stored one, and at the same time the instantaneous values are sequentially compared with the stored relative minimum value so that the electron producing apparatus is deenergized when an instantaneous value assumes a certain magnitude relative to the stored relative minimum value.