Patent ID: 6702548
Filing Date: 2004-03-09
Classification: F04D

Abstract:
A tubeaxial fan assembly comprising:a tubular propeller housing; a propeller rotatably supported in the housing for rotation about a rotational axis; and a drive assembly operable to rotate the propeller, said propeller including a central hub and a plurality of blades fixed relative to the hub to project radially therefrom, each of said blades presenting a root adjacent the hub and a tip spaced radially outward from the root, each of said tips being spaced from the rotational axis a tip radius, each of said blades presenting a chord length that is smaller at the root and tip relative to a maximum chord length location spaced between the root and tip, each of said blades presenting a stagger angle that is relatively greater at the tip than at the root, each of said blades presenting a camber height that is smaller at the root and tip relative to a maximum camber height location spaced between the root and tip, said drive assembly including shaft that is fixed relative to the hub and extending at least generally along the rotational axis, a bearing rotatably supporting the shaft, and a protective bearing cover encasing the bearing and at least a portion of the shaft, said drive assembly including an endless element that is drivingly connected to the shaft and extends outside the housing, said drive assembly further including an element cover that is located within the housing and at least substantially encloses the element within the housing, said bearing cover presenting a wall extending along, and generally parallel to, the at least a portion of the shaft in a covering relationship to the bearing and the at least a portion of the shaft, said wall being spaced from the element cover so that said at least a portion of the shaft is located between the element cover and said wall, said wall being spaced from the rotational axis a cover dimension that is less than about one-third the tip radius, said element cover presenting opposite upstream and downstream ends spaced along the rotational axis, said element cover tapering toward the upstream and downstream ends.