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:
Dec. 28, 1982
Filed:
Jun. 18, 1980
Lynn E Jensen, Clearfield, UT (US);
Cutter Laboratories, Inc., Berkeley, CA (US);
Abstract
Air bubbles in a transparent intravenous solution conduit are detected, regardless of whether the solution is opaque or clear, by directing a light source at the conduit and detecting light shining through the solution with a first light sensor while detecting light reflected from the interior wall of the conduit with a second light sensor. If liquid is present in the conduit, whether clear or opaque, one sensor will see a low light level while the other sees a high level. If air is present, both sensors see a high light level. By EXCLUSIVE-OR'ing the outputs of the two sensors, a logic signal is obtained which is high only when the presence of liquid in the conduit is being detected. Means using two sensor assemblies spaced axially along the conduit, and a counter associated with each, are also provided to allow passage of minor air bubbles, and to provide a backup signal representative of a predetermined volume of air passing either assembly independently of the other.