Patent ID: 6716274
Filing Date: 2004-04-06
Classification: B01D,D01F,D04H,Y02A

Abstract:
An air filter assembly comprising:(a) a housing including an air inlet, an air outlet, a spacer wall separating said housing into a filtering chamber and a clean air chamber; said spacer wall including a first air flow aperture therein; (b) a first filter construction positioned in air flow communication with said first air flow aperture in said spacer wall; said first filter construction including an extension of a pleated filter media composite defining a filter construction inner clean air chamber; (i) said first filter construction being oriented with said filter inner clean air chamber in air flow communication with said spacer wall first air flow aperture; (ii) said pleated filter media composite including a substrate, the substrate having an efficiency greater than 11% when measured according to ASTM-1215-89, with 0.78&mgr; monodisperse polystyrene spherical particles, at 20 fpm (6.1 meters/min), a permeability of about 2 to 900 meters-minâˆ’1, a basis weight not greater than 200 grams-mâˆ’2 and a thickness of 25 to 800 microns, the substrate at least partially covered by a layer of fine fiber having a thickness of about 1-8 times the fine fiber diameter; (A) said fiber comprising a diameter of about 0.01 to 0.5 microns that after exposure for a test period of 16 hours to test conditions of 140Â° F. air and a relative humidity of 100% retains greater than 30% of the fiber unchanged for filtration purposes (c) a pulse-jet cleaning system oriented to direct a pulse of air into said filter construction inner clean air chamber.