Air filter assembly with removable filter elements

Claim 1

IN A FILTER ASSEMBLY, THE COMBINATION OF: A HOUSING HAVING AN INLET AND AN OUTLET, AT LEAST ONE PAIR OF SUBSTANTIALLY PARALLEL RAILS BEING VERTICALLY SPACED AND EXTENDING ACROSS THE INLET OF SAID HOUSING, A SEALING MEANS MOUNTED ON AND EXTENDING THE LENGTH OF EACH SAID RAIL, EACH SAID SEALING MEANS POSITIONED ON SAID RAIL IN A LOCATION SPACED AWAY FROM THE VERTICAL EXTREMITY OF THE RAIL AND FACING THE INLET OF THE HOUSING, AT LEAST ONE FILTER ELEMENT HAVING A FRAME AND FILTERING MEDIA, SAID FRAME HAVING A PAIR OF SPACED AND LATERALLY EXTENDING U-SHAPED CHANNELS, EACH SAID U-SHAPED CHANNEL OPEN IN A DIRECTION AWAY FROM THE OTHER SAID CHANNEL FOR SURROUNDING ONE OF SAID RAILS AND ENGAGING SAID SEALING MEANS, THE LOWER OF SAID CHANNELS ENGAGING THE UPPER EXTREMITY OF THE LOWER OF SAID PAIR OF RAILS FOR SUPPORTING SAID FILTER ELEMENT ON SAID RAIL WITHOUT SUPPORTING THE WEIGHT OF THE FILTER ELEMENT ON SAID SEALING MEANS, AND AN OPENABLE DOOR IN SAID HOUSING AT THE END OF SAID RAILS FOR PERMITTING REMOVAL AND REFITTING OF SAID FILTER ELEMENT ON SAID RAILS.