Abstract: An air diffuser includes first and second walls disposed in spaced side-by-side relationship and cooperating to define a passage for the flow of air in one direction between said walls. A pair of flanges extend towards each other from the downstream edges of the walls and defining an elongated outlet slot narrower than the width of said passage. A deflector vane is narrower than the passage and is disposed in the passage in a plane spaced upstream from the slot and generally parallel to said flanges. The deflector vane includes an inverted U-shaped central channel and flanges extending away from each other from the down stream ends of the U-shaped chanel and arranged generally parallel to the flanges defining the slot. The opposite ends of the vane are engaged in a U-shaped support with a spring engaging one wall of the U-shaped support and biasing the vane flanges into sliding engagement with the other wall.

Abstract: The flow control unit includes a shell or housing defining a flow passage and a damper assembly disposed in the housing for controlling the volume of air flowing through the flow passage. The damper assembly includes a pivotally mounted damper blade which is partially surrounded by a pair of perforated members, one located upstream and the other located downstream of the damper blade pivot axis. Each of the perforated members have an arcuate cross-sectional shape and is disposed in close proximity to the travel path of one of the outer edges of the damper blade. The perforate members preferably have an open edge spaced from a longitudinal plane extending through the damper blade pivot axis. During initial damper blade travel from the closed position toward the open position, substantially all of the air flows through the perforations of the perforate members.

Abstract: An inlet plenum extends into a control box and opens into the interior of the control box. Conditioned air is introduced into the box through the inlet plenum and flows from the box, to an area being serviced, through an outlet spaced from the plenum opening in the box. A damper is positioned at the plenum opening and it and the plenum at the opening having conforming shapes, i.e., segments of a circle. The damper closes over the discharge opening and, to vary the volume of air flowing through the box, pivots away from the opening about an axis offset from the center of the arc of the damper and the plenum opening. When the damper is closed on the plenum opening, the centers of the arcuate plenum opening and the damper are coincident and, relative to a central plane parallel to air flow through the plenum, are offset from that plane so that the damper is moved away from the plenum opening by air flow.

Abstract: Air flow volume in a delivery duct is sensed in the form of changes in duct pressure and the sensed pressure is fed back to a diaphragm assembly which is part of a thermostatic control located in the room to which hot or cold air is being delivered. Dependent upon the sensed pressure, the diaphragm assembly throttles a bleed opening in the supply line of a pneumatic actuator, which actuator determines the position of a damper in the duct to thereby control the volume of air flow in the duct. A bellows is also part of the thermostatic control and senses room temperature to establish a spring force on the diaphragm assembly and against which the sensed pressure must act. The bellows is adjustable to afford room temperature selection. The bellows and a compression spring act on a master lever, the compression spring reacts against the bellows force.