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:
Oct. 20, 1981
Filed:
Dec. 11, 1979
Applicant:
Inventors:
Karl Beinitz, Cologne, DE;
Joachim Schubert, Wesseling, DE;
Assignee:
Leybold-Heraeus GmbH, Postfach, DE;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G08B / ; H05B / ;
U.S. Cl.
CPC ...
315135 ; 315107 ; 315136 ; 324405 ;
Abstract
In a circuit for an ionization vacuum gauge having a thermionic filament, a control circuit receptive of a control current for controlling the filament and a switch for applying the control current to the control circuit, a circuit is provided for indicating a filament interruption independent of the state of the switch. The circuit includes at least one resistor by-passing the switch to provide a continuous sensing current to the filament and a detector for detecting the interruption in the sensing current and for indicating such an interruption.