Ceiling air diffuser

Claim 1

An air diffuser of the elongated-slot type for mounting on a ceiling tee bar, comprising: an elongated air plenum chamber housing; at least one elongated vertically disposed outwardly flaring lower side wall, depending from the coRresponding side wall of said air plenum chamber housing and defining the outerside of an elongated air discharge slot of the air diffuser; a pair of vertically disposed transverse end plates, one at either end of the air diffuser, each of said end plates having a centrally located notch adapted to fit over and engage the vertically upstanding web of the ceiling tee bar, so that when the air diffuser is mounted in place, the vertical web and one horizontal flange of the ceiling tee bar appear normally as in other areas of the ceiling, but help to hide from view the operating mechanism of the diffuser; at least one elongated air flow control vane pivotally mounted at its upper end, with its lower free end resiliently urged toward one side of the elongated air discharge slot to a position in which said air flow control vane cuts off communication between said air plenum chamber housing and the air discharge slot; and means for selectively positioning the free lower end of said air flow control vane and variably opening communication between said plenum chamber housing and the air discharge slot, thereby regulating the effective air outlet opening.