Air damper assembly including sidewall sealing means

Claim 1

AN AIR DAMPER ASSEMBLY COMPRISING IN COMBINATION: (A) A RECTANGULAR FRAME HAVING TOP, BOTTOM AND OPPOSED SIDE MEMBERS DEFINING A PLANE PERPENDICULAR TO THE AIR FLOW PATH, EACH MEMBER HAVING A LONGITUDINALLY EXTENDING SHELF PARALLEL TO THE FRAME PLANE SO AS TO DEFINE A RECTANGULAR SHELF AROUND AN AIR FLOW OPENING; (B) A BLADE ASSEMBLY INCLUDING A PLURALITY OF INDIVIDUAL LONGITUDINALLY EXTENDING BLADES, EACH OF SAID BLADES SUPPORTED AT OPPOSITE ENDS BY PIVOT MEANS FIXEDLY SECURED IN SAID FRAME OPPOSED SIDE MEMBER SHELVES, EACH OF SAID BLADES HAVING AN UPPER AND LOWER SECTION AND AN INTERMEDIATE OFFSET SECTION, SAID OFFSET SECTION HAVING A CENTER-LINE DEFINING THE BLADE PIVOTAL AXIS, THE LENGTH OF EACH OF SAID BLADES BEING GREATER THAN THE OPENING BETWEEN OPPOSED SIDE MEMBER SHELVES SO THAT THE SIDE EDGE PORTIONS OF SAID BLADE UPPER SECTION OVERLAP THE FRAME OPPOSED SIDE MEMBER SHELVES ON ONE SIDE THEREOF AND THE SIDE EDGE PORTIONS OF SAID BLADE LOWER SECTION OVERLAP THE FRAME OPPOSED SIDE MEMBER SHELVES ON THE OTHER SIDE THEREOF WHEREBY THE SIDE EDGE PORTIONS AND THE FRAME OPPOSED SIDE MEMBER SHELVES EFFECT A SEAL WHEN THE BLADE ASSEMBLY IS IN A CLOSED POSITION, EACH OF SAID BLADE LONGITUDINAL EDGES IN SEALING ENGAGEMENT WITH THE LONGITUDINAL EDGE OF THE ADJACENT BLADE, THE UPPER LONGITUDINAL EDGE OF THE UPPERMOST BLADE AND THE LOWER LONGITUDINAL EDGE OF THE LOWERMOST BLADE OVERLAPPING THE FRAME TOP AND BOTTOM SHELVES, RESPECTIVELY, WHEN SAID BLADE ASSEMBLY IS IN A CLOSED POSITION; AND, (C) LINKAGE MEANS INTERCONNECTING SAID BLADES FOR SIMULTANEOUS OPENING AND CLOSING OF SAID BLADES COMPRISING SAID BLADE ASSEMBLY.