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:
Feb. 12, 2008
Filed:
Mar. 07, 2003
Derek S. Baker, Lake Elmo, MN (US);
Brandon H. Harmon, St. Paul, MN (US);
Derek S. Baker, Lake Elmo, MN (US);
Brandon H. Harmon, St. Paul, MN (US);
3M Innovative Properties, St. Paul, MN (US);
Abstract
A respiratory protection circuit of the type having an air flow regulator disposed in an air flow path between an air supply and a respirator is improved by including an air flow splitter and a bi-directional valve. The air flow splitter is disposed in the air flow path upstream from the air flow regulator, the splitter dividing the air flow path into first and second downstream flow paths, with the first downstream flow path leading to the respirator. The bi-directional valve is disposed in the second downstream flow path wherein the bi-directional valve prevents excessive downstream air flow therethrough and prevents upstream air flow therethrough.