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. 31, 2013
Filed:
Sep. 30, 2009
Britton G. Billingsley, St. Paul, MN (US);
Larry A. Brey, Woodbury, MN (US);
Britton G. Billingsley, St. Paul, MN (US);
Larry A. Brey, Woodbury, MN (US);
3M Innovative Properties Company, St. Paul, MN (US);
Abstract
An air filter that includes a primary filter and a polishing filter. The primary filter comprises a monoliththat contains active-particulate. The air-to-be-filtered travels through the primary filter in a path generally parallel to the passageways. The polishing filterhas first and second major surfaces and also contains active-particulate. The polishing filter is generally arranged such that air travels from the first major surface to the second major surface when passing through it. The inventive filter demonstrates extraordinary performance over the same primary and polishing filters taken individually.