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:
Aug. 19, 1997
Filed:
Oct. 24, 1994
Mark K Debe, Stillwater, MN (US);
Gregory Yuschak, Hudson, WI (US);
Edward E Parsonage, Minneapolis, MN (US);
Richard J Poirier, White Bear Lake, MN (US);
Lowell R Miller, White Bear Lake, MN (US);
Minnesota Mining and Manufacturing Company, St. Paul, MN (US);
Abstract
An exposure indicating apparatus for monitoring air flowing along a flow-through path extending from the external environment through an air purifying respirator cartridge and into a face mask. A processor housing is releasably attached to the flow-through path so that it can be removed allowing ambient air to enter the flow-through path at the attachment location. A reversible sensor with at least one property responsive to a concentration of a target species within an environment is in fluid communication with the flow-through path. A processing device in the processor housing generates a concentration signal as a function of the at least one property of the reversible sensor. An indicator provides an active indication in response to the concentration signal. A flow-through housing may form a portion of the flow-through path. The flow-through housing may be interposed between the air purifying cartridge and the face mask. The reversible sensor may be located in the processor housing, the air purifying respirator cartridge or the flow-through housing. The sensor is coupled to the processing device by a coupler.