Adjustable frame structure for air filters and the like

Claim 1

AN ADJUSTABLE FRAME STRUCTURE FOR WINDOW AIR-FILTERS AND THE LIKE, COMPRISING: A FIRST GENERALLY-RECTANGULAR FRAME INCLUDING A FIRST PAIR OF SUBSTANTIALLY IDENTICAL HORIZONTAL-EXTENDING VERTICALLY SPACED-APART RAILS AND A FIRST PAIR OF END-FRAME MEMBERS SECURED TO OPPOSITE ENDS OF SAID RAILS TO HOLD SAID RAILS IN SUBSTANTIALLY PARALLEL RELATIONSHIP TO EACH OTHER; EACH OF SAID RAILS HAVING FORMED THEREIN A FIRST KEYED CHANNEL, A SECOND KEYED CHANNEL, A THIRD CHANNEL AND A FOURTH CHANNEL, EACH OF SAID CHANNELS EXTENDING THROUGHOUT THE ENTIRE LENGTH OF SAID RAILS; SAID FOURTH CHANNEL, EACH OF SAID RAILS FACING INWARDLY OF SAID FRAME TO PERMIT MOUNTING FOR AN AIR FILTER THEREIN, SAID FIRST KEYED CHANNEL IN EACH OF SAID RAILS FACING OPPOSITELY TO SAID FOURTH CHANNEL, SAID SECOND KEYED CHANNEL IN EACH OF SAID RAILS FACING HORIZONTALLY OUTWARD FROM ONE SIDE OF SAID FRAME AND HAVING A SUBSTANTIALLY RECTANGULAR CROSS-SECTION, AND SAID THIRD CHANNEL IN EACH OF SAID RAILS FACING OPPOSITELY TO SAID SECOND KEYED CHANNEL; A SECOND GENERALLY RECTANGULAR FRAME OF SUBSTANTIALLY THE SAME FORM AS SAID FIRST FRAME AND INCLUDING A SECOND PAIR OF HORIZONTALLY-EXTENDING RAILS SUBSTANTIALLY IDENTICAL WITH EACH OTHER AND WITH SAID FIRST PAIR OF RAILS AND EACH HAVING A FIRST AND SECOND KEYED CHANNEL AND A THIRD AND A FOURTH CHANNEL ALL OF WHICH ARE OF SUBSTANTIALLY THE SAME FORM AS SAID CHANNELS IN SAID FIRST PAIR OF RAILS, AND A SECOND PAIR OF ENDFRAME MEMBERS SECURED TO OPPOSITELY ENDS OF SAID SECOND PAIR OF RAILS TO HOLD SAID SECOND PAIRS OF RAILS IN SUBSTANTIALLY PARALLEL, VERTICALLY SPACED-APART RELATIONSHIP, SAID SECOND PAIR OF END-FRAME MEMBERS BEING OF SUBSTANTIALLY THE SAME FORM AS SAID FIRST PAIR OF END-FRAME MEMBERS; ONE OF SAID FIRST PAIR OF END-FRAME MEMBERS HAVING A PAIR OF KEY MEMBERS INTEGRALLY FORMED THEREON, EACH OF SAID KEY MEMBERS HAVING A KEY PORTION OF SUBSTANTIALLY RECTANGULAR CROSS-SECTION RETAINED IN CLOSELY-FITTING LONGITUDINALLY-SLIDABLE RELATIONSHIP IN A DIFFERENT ONE OF SAID SECOND KEYED CHANNELS IN SAID SECOND PAIR OF RAILS, AND ONE OF SAID SECOND PAIR OF ENDFRAME MEMBERS HAVING A PAIR OF KEY MEMBERS INTEGRALLY FORMED THEREON, EACH OF SAID LAST-NAMED KEY MEMBERS HAVING A KEY PORTION OF SUBSTANTIALLY RECTANGULAR CROSS-SECTION RETAINED IN CLOSELY-FITTING LONGITUDINALLY-SLIDABLE ENGAGEMENT IN A DIFFERENT ONE OF SAID SECOND KEYED CHANNELS IN SAID FIRST PAIR OF RAILS; RESILIENT GASKETS EXTENDING THE LENGTH OF SAID RAILS AND RETAINED IN SAID FIRST KEYED CHANNELS THEREOF; AND CONNECTOR MEANS EXTENDING LONGITUDINALLY INTO THE ENDS OF SAID THIRD CHANNELS AT THE ENDS OF EACH OF SAID RAILS AND SECURED TO SAID END-FRAME MEMBERS AND THE INTERIOR WALLS OF SAID THIRD CHANNELS FOR SECURING SAID END-FRAME MEMBERS TO SAID RAILS.