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:
Jun. 24, 2008
Filed:
Mar. 31, 2005
Yu Chen, Shoreview, MN (US);
C. Peter Howard, Humboldt, TN (US);
Michael G. Snow, White Bear Lake, MN (US);
Yu Chen, Shoreview, MN (US);
C. Peter Howard, Humboldt, TN (US);
Michael G. Snow, White Bear Lake, MN (US);
Medical Graphics Corporation, St. Paul, MN (US);
Abstract
A device for directly measuring a person's respiratory exchange ratio (RER) utilizes a Zn-air battery cell and a constant current load circuit as an Opump capable of drawing oxygen from expired air. A thermistor located in the flow path forms a leg of a bridge circuit whose output is proportional to oxygen concentration in the expired air and, therefore, to oxygen uptake. The thermistor flowmeter circuit utilizes the thermal conductivity differences between Oand COto provide a measure at the relative ratio of the two gases present.