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:
Apr. 10, 2001
Filed:
Sep. 01, 1998
Applicant:
Inventor:
Artur Meisberger, St. Wendel, DE;
Assignee:
Fresenius AG, Bad Homburg, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01N 2/904 ;
U.S. Cl.
CPC ...
G01N 2/904 ;
Abstract
An ultrasonic transmitter, particularly for an air bubble detector, having a transmitting stage and an ultrasonic crystal. The transmitting stage includes a multivibrator having a time-base circuit with two stable output states. A timing element is interconnected in the feedback loop of the time-base circuit. An ultrasonic crystal is interconnected with the feedback loop of the time-base circuit so that the electrical circuit oscillates at or near a resonance frequency of the ultrasonic crystal. The ultrasonic crystal may be disconnected so that the multivibrator oscillates automatically at its own natural frequency.