Patent ID: 6843820
Filing Date: 2005-01-18
Classification: B01D,Y10S

Abstract:
1. A filter assembly including: a stiff frame having front and rear major surfaces, comprising a perimeter portion defining the perimeters of said surfaces and having opposite first and second end parts, said frame having a through passageway between said front and rear surfaces surrounded by said perimeter portion; a filter element comprising a sheet of flexible filter media having opposite major inlet and outlet side surfaces, opposite ends, and opposite generally parallel edges extending between said opposite ends, an end portion of said sheet at each of said ends extends at about a right angle to said opposite edges and has structure defining spaced first and second through openings; and structure on said frame for receiving and positioning said filter element with said sheet of filter media extending across said passageway with said inlet surface of said sheet facing the same direction as said front surface of said frame and with said end portions of said filter element extending along said opposite end parts of said perimeter portion, said structure on said frame including first and second generally parallel spaced linear abutments extending along said perimeter portion between said end parts and laying along said opposite edges of said sheet of filter material, and spaced first and second projections on each of said end parts of said frame engaged in the first and second openings at a different one of the ends of said sheet of filter material; said first projection at said first end part being spaced the same first distance from said first linear abutment in a direction normal to said abutments as said first projection at said second end part is spaced from said second linear abutment in a direction normal to said abutments, and said second projection at said first end part being spaced the same second distance from said second linear abutment in a direction normal to said abutments as said second projection at said second end is spaced from said first linear abutment in a direction normal to said abutments; and said first and second distances being different so that said filter element can be mounted on said frame with the structure at either of the ends of the sheet of filter material engaged with the projections at either of the end parts of the frame while the filter element can only be mounted on the frame with said inlet surface of said sheet facing the same direction as said front surface of said frame.