Combination acoustic ceiling panel and air diffuser

Claim 1

IN A VENTILATING SYSTEM, THE COMBINATION WITH A WALL OR A CEILING OF A SPACE TO BE VENTILATED OF AN INNER WALL SPACED INTERIORLY OF SAID WALL OR CEILING, SAID INNER WALL HAVING AN OPENING THEREIN, AND AN AIR CONTROL FIXTURE IN SAID OPENING COMPRISING A RIGID PANEL HAVING FIRST AND SECOND SPACED PLATESE, SAID FIRST PLATE BEING DISPOSED IN THE PLANE OF SAID INNER WALL AND CLOSING SAID OPENING, SAID FIRST PLATE HAVING A PLURLAITY OF DIFFUSION PASSAGES FOR DIFFUSING WAVES OF SOUND MOVING IN A DIRECTION, SAID SECOND PLATE HAVING A REFLECTIVE SURFACE FOR REVERSELY TURNING THE DIFFUSED WAVES OF SOUND, SOUND DEADENING MEANS BETWEEN SAID FIRST AND SECOND PLATES TO ABSORB THE REVERSELY TURNED WAVES OF SOUND, SAID SECOND PLATE BEING COEXTENSIVE IN SIZE WITH AND SPACED FROM SAID FIRST PLATE IN PARALLEL DISPOSITION THEREWITH TO FORM A FIRST PLENUM CHAMBER, MEANS FORMING WITH SAID RIGID PANEL A SECOND PLENUM CHAMBER HAVING A PORTION OF SAID SECOND PLATE AS ONE WALL THEREOF, SAID SECOND PLATE HAVING A PLURALITY OF AIR PASSAGES FORMED IN SAID PORTION OF SAID SECOND PLATE TO FORM AN AIR INLET INTO SAID FIRST PLENUM CHAMBER, SAID SECOND PLENUM CHAMBER HAVING A VALVE-CONTROLLED OPENING THEREIN FOR CONDUCTING AIR IN CONTROLLED QUANTITIES TO SAID AIR INLET, WHEREBY THE RATE OF FLOW OF AIR THROUGH SAID FIXTURE IN DETERMINED BY ADJUSTMENT OF SAID VALVE-CONTROLLED OPENING FOR SIMULTANEOUS DIFFUSION OF AIR AND DEADENING OF SOUND IN THE SAME FIXTURE.