ROOF FAN Russian patent published in 2006 - IPC F04D17/16 

FIELD: pumping engineering.

SUBSTANCE: roof fan comprises housing (1), motor (2), working wheel (3) with blades (11), main disk (9), covering disk (10), and ring space between disk (10) and sucking branch pipe (4). Housing (1) is connected with cap (5) provided with flaps (7) through frame (20). The flaps are mounted at an angle of ≤ 60° to axis (8) of wheel (3) and rotate around axis (23) in operation of the fan. According to the first version, the width H of blades (11), which is equal to the distance between disks (9) and (10) at the maximum diameter D of circumference described by blades (11) and minimum distance B between the walls of housing (1) are H ≥ 0.25D and B = (1.05-1.5)D. According to the second version, housing (1) is provided with ring panel (13) to define space (16) and the parameters of the fan are the following: H ≥ 0.35D, L = (0.01-0.1)H, d = (0.05-0.1)D, and B = (1.05-1.5)D, where L is the overlapping of blades (11) by edge (14) and d is the distance from blades (11) to edge (14).

EFFECT: damped noise and reduced sized.

17 cl, 8 dwg