Furnace filter

Claim 1

A FILTER ADAPTED TO BE ATTACHED TO A WALL HAVING A FLUID INLET OPENING TO EFFECT THE REMOVAL OF DUST AND THE LIKE FROM FLUID PASSING THROUGH THE OPENING, COMPRISING: (A) A FILTER SUPPORT STRUCTURE INCLUDING FILTER GUIDE MEMBERS ARRANGED IN A SPACED RELATION TO DEFINE AN AIR PASSAGEWAY THERETHROUGH, SAID GUIDE MEMBERS ALSO DEFINING A FILTER RECEIVING OPENING ON ONE SIDE OF SAID PASSAGEWAY AND A FILTER REMOVAL OPENING ON THE OTHER SIDE OF SAID PASSAGEWAY; (B) A ROLL OF FILTER MATERIAL SUPPORTED ADJACENT SAID SUPPORT STRUCTURE AND INCLUDING AN UNROLLED SECTION SLIDABLY CARRIED BY SAID GUIDE MEMBERS SO AS TO EXTEND TRANSVERSELY ACROSS SAID PASSAGEWAY, SAID UNROLLED FILTER SECTION ENTERING SAID GUIDE MEMBERS THROUGH SAID RECEIVING OPENING AND BEING WITHDRAWABLE FROM SAID GUIDE MEMBERS THROUGH SAID EMOVAL OPENING; (C) SCREEN MEANS EXTENDING TRANSVERSELY ACROSS SAID PASSAGEWAY TO MAINTIAN SAID UNROLLED SECTION OF FILTER MATERIAL TRANSVERSELY ACROSS SAID AIR PASSAGEWAY, SAID SCREEN MEANS INCLUDING A STATIONARY SCREEN AND A MOVABLE SCREEN IN SPACED RELATION SO AS TO DEFINE A FILTER COMPARTMENT EXTENDING FROM THE FILTER RECEIVING OPENING ON ONE SIDE OF THE AIR PASSAGEWAY TO THE FILTER REMOVAL OPENING ON THE OTHER SIDE OF THE AIR PASSAGEWAY; (D) SAID MOVABLE SCREEN BEING MOVABLE BETWEEN FIRST AND SECOND POSITIONS RELATIVE TO AND PARALLEL TO SAID STATIONARY SCREEN, SAID MOVABLE SCREEN IN SAID FIRST POSITION BEING IN SPACED RELATION TO SAID STATIONARY SCREEN AND SANDWICHING A FILTER SECTION AGAINST THE STATIONARY SCREEN SUFFICIENTLY TO HOLD THE FILTER SECTION AGAINST THE STATIONARY SCREEN BUT NOT TO THE EXTENT OF APPRECIABLY CRUSHING ANY PORTION OF THE FILTER SECTION, SAID MOVABLE SCREEN IN ITS SECOND POSITION BEING FURTHER SPACED FROM SAID STATIONARY SCREEN AND RELEASING SAID FILTER SECTION SO THAT SAID FILTER MATERIAL FACILELY SLIDES THROUGH SAID COMPARTMENT IN SAID GUIDE MEMBERS; AND, (E) A PAIR OF LEVER ARMS EACH HAVING SHAFT PORTIONS AND PORTIONS OFF-SET FROM SAID SHAFT PROTION, SAID SHAFT PORTIONS BEING ROTATABLY CARRIED BY SAID FILTER SUPPORT STRUCTURE, THE OFF-SET PORTIONS OF THE LEVER ARMS ENGAGING THE SCREEN AT SPACED LOCATIONS SO THAT ROTATION OF BOTH LEVER ARMS MOVES THE MOVABLE SCREEN IN A PARALLEL MANNER RELATIVE TO SAID STATIONARY SCREEN AND ROTATION OF ONE OF SAID ARMS MOVES THE MOVABLE SCREEN ANGULARLY RELATIVE TO SAID STATIONARY SCREEN.