| 摘要 |
<p>A system for keeping constant differential pressure in a clean room is provided to maintain cleanness of the clean room by maintaining VP speed no matter when a vent hood operates or not by closing an A damper and proportionally driving a B damper when the vent hood is not operated. A system for keeping constant differential pressure in a clean room comprises a vent hood, a return diffuser, a duct, an A damper, and a B damper. The duct is connected between the discharge vent hood and the return diffuser to set VP speed, which is checked at the moment of operation of the vent hood, as a set point. The A damper is fully opened and the B damper is closed when the vent hood operates. A user can set the differential pressure at this moment. The A damper is closed and the B damper is proportionally operated to keep the VP set point when the vent hood is not operated, therefore the VP speed is constantly maintained no matter when the vent hood operates or not.</p> |
