Patent ID: 9744329
Date: 2017-08-29
CPC Classifications: A61M,A62B,B01D

Claim:
1. An air filtering device that comprises: (a) a housing extending from a first location to a second location along a longitudinal dimension, wherein the housing includes three or more subsections disposed in series, each subsection containing a filter element; (b) an inlet disposed at the first location on the housing; (c) an upstream air distribution system in fluid communication with the inlet, wherein the upstream air distribution system defines a separate port for each of the three or more subsections and a plenum in upstream fluid communication with each of the subsections through the corresponding separate port, wherein each of the separate ports is positioned between the first location and all of the three or more subsections along the longitudinal dimension and each of the separate ports is adjacent the plenum such that air is configured to pass from the plenum and through the separate ports; (d) a downstream air distribution system located in fluid communication with each subsection; and (e) an outlet in fluid communication with the downstream air distribution system; wherein the upstream air distribution system, the three or more subsections, and downstream air distribution system are configured such that air entering the inlet passes in different directions toward each of the three or more subsections and flows through only one subsection between the inlet and the outlet.