APPARATUS FOR REVERSING AIRFLOW WITHIN A DUCT

摘要

Apparatus is provided for reversing airflow within a duct utilizing a single, stationary fan. The apparatus includes a valve system which through the utilization of a cam or solenoid provides for movement of the valves to reverse the airflow. The apparatus includes a duct having a first end and a second end, which are open, and a stationary fan placed therebetween. The fan has an intake side and an outlet side; at all times while the fan blades are rotating, air is flowing from the intake side to the outlet side. In one embodiment, valves are hingedly attached to the sides of the duct such that their movement by a solenoid and linkage can open and close ports in the ends of the duct. In another embodiment, flexible valves are located adjacent the fan at opposite ends of an axis perpendicular to the axis of rotation of the fan blades and close one half of the openings at the first and second end. The valves are rotated in such a manner to close the other half of the openings at each end to thus reverse the air flow through the duct. At all times, air flow across the fan maintains the same direction. In another embodiment, rigid arcuate valves surround the fan and have ports opposite one another. The valves are rotated by a solenoid or cam system in such a manner that the air flow through the duct is reversed.