| 摘要 |
<p>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. The damper is closed against air flow pressure by inflation of an air bladder, air inflates the bladder being drawn from the air flow through the inlet plenum and the flow of air to the bladder being controlled in accordance with the temperature of the area being serviced and the volume of air flowing from the box. Air flow volume is determined for control purposes by sensing box pressure at the outlet. The interior walls of the box are acoustically treated and, for acoustical purposes, a dead air space is also defined between the discharge opening and the box outlet.</p> |
