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:
Sep. 09, 2003
Filed:
Mar. 20, 2000
Applicant:
Inventor:
Ian T. Petherbridge, West Sussex, GB;
Assignee:
3M Innovative Properties Company, St. Paul, MN (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
A62B 2/900 ;
U.S. Cl.
CPC ...
A62B 2/900 ;
Abstract
A respirator that comprises a head piece ( ) that is shaped to form a breathing zone ( ) around at least the nose and mouth of the wearer, and an air flow passage ( ) for supplying a forced flow of air to the breathing zone. The air flow passage has a constricted portion ( ) that includes a flow detecting orifice ( ). The forced flow of air generates suction at the flow-detecting orifice. A pressure-responsive indicator device ( ) is in fluid communication with the flow-detecting orifice through a tube ( ) and is operable to alert the wearer if the suction generated by the air flow through the passage falls below a predetermined value.