초록 ▼

An axial fan is disclosed that includes a hub supported for rotation around the longitudinal axis of the fan, a plurality of impeller blades attached to the hub and extending radially from the axis of rotation, a shroud assembly including a band encircling the blades and spaced from the tips of the

An axial fan is disclosed that includes a hub supported for rotation around the longitudinal axis of the fan, a plurality of impeller blades attached to the hub and extending radially from the axis of rotation, a shroud assembly including a band encircling the blades and spaced from the tips of the blades a sufficient distance to provide ample clearance to avoid contact between the blades and the band during shipment and operation of the fan, the shroud further including an orifice positioned upstream of the blades for preventing air from flowing between the orifice and the band, the orifice having a downstream end located adjacent to but spaced from the impeller blades and having a diameter such that the impeller blades extend outwardly from the hub beyond the orifice so that the flow of air over the tips of the impeller blades is substantially reduced, which increases the efficiency of the fan.

대표청구항 ▼

An axial fan comprising a hub, means supporting the hub for rotation around the longitudinal axis of the fan, a plurality of impeller blades attached to the hub and extending radially from the axis of rotation, a shroud assembly including a band encircling the blades and spaced from the tips of the

An axial fan comprising a hub, means supporting the hub for rotation around the longitudinal axis of the fan, a plurality of impeller blades attached to the hub and extending radially from the axis of rotation, a shroud assembly including a band encircling the blades and spaced from the tips of the blades a sufficient distance to provide ample clearance to avoid contact between the blades and the band during shipment and operation of the fan, said shroud further including an orifice positioned upstream of the blades, said band having a diameter that is about 106% of the diameter of the orifice means for preventing air from flowing between the orifice and the band, said orifice having a downstream end located adjacent to but spaced from the impeller blades, said impeller blades having a diameter that is about 103% of the diameter of the orifice so that the impeller blades extend outwardly from the hub beyond the orifice to reduce the flow of air over the tips of the impeller blades substantially while providing ample clearance between the tips of the impeller blades and the band.