Axial flow fan with adjustable blades

Abstract

An axial flow fan wherein the cylindrical housings for the shanks of blades are mounted on a flat plate-like circular base of the hub which is rotated by an electric motor through the medium of a belt transmission and a hollow shaft. The motor, transmission and shaft are mounted at one side and the housings are mounted at the other side of the base. The shanks of the blades are turnable simultaneously by a mechanism which has a rod-like pusher extending axially through the base, a double-acting hydraulic or pneumatic cylinder whose piston is rigid with and can move the pusher axially, a displacing disk attached to that end of the pusher which is nearer to the housings, a lever rigidly affixed to each shank, and discrete linkages coupling the disk with each lever so that the levers rotate the respective shanks and blades simultaneously clockwise when the piston moves the pusher axially in one direction and that the levers rotate the respective shanks and blades simultaneously counterclockwise when the piston moves the pusher axially in the other direction. A sleeve on the base supports tie rods which confine the disk to movements in the axial direction of the hub. Alternatively, the sleeve can be omitted and the cylinder can be mounted on the base in a position to support the tie rods. If the cylinder rotates with the hub, the pusher has concentric channels which connect the cylinder chambers with a source of pressurized fluid. The channels can be omitted if the cylinder need not rotate with the hub; the cylinder chambers are then directly connected with the source of pressurized fluid by suitable conduits.

Dependencies are inferred from the claim text.