Motor-Driven Fan With an Assembly for Minimizing Vibration and Strain

A motor-driven fan, comprising:

• an inboard bracket defining an outlet;
• an outboard bracket;
• a stator comprising a plurality of laminations;
• a screw clamping the stator between the inboard bracket and the outboard bracket;
• an armature comprising a shaft being elongate in an axial direction, a commutator supported by the shaft, and a set of windings being electrically coupled to the commutator;
• a set of bearings mounted to at least one of the inboard bracket and the outboard bracket, the set of bearings providing the shaft with support in a radial direction that is perpendicular to the axial direction, the set of bearings further supporting the shaft in the axial direction so as to position the set of windings proximate the stator;
• a fan housing connected to the inboard bracket, the fan housing defining an inlet that is in fluid communication with the outlet of the inboard bracket;
• a plurality of fan wheels being in an axially stacked arrangement within the fan housing;
• a nut fastening the plurality of fan wheels to the shaft;
• and
• the inboard bracket comprising a first axial surface and a second axial surface both of which face toward and engage the stator, and
• the outboard bracket comprising a third axial surface and a fourth axial surface both of which face toward and engage the stator, the first axial surface and the third axial surface being adjacent to the screw, the first axial surface being spaced apart a first axial distance from the third axial surface, the second axial surface being spaced apart a second axial distance from the fourth axial surface, the first axial distance being less than the second axial distance.

A motor-driven fan configured to operate at 15,000 to 30,000 rpm for compressing air to less than 15 psig, the motor-driven fan comprising:

• an inboard bracket defining an outlet;
• an outboard bracket;
• a stator comprising a plurality of laminations;
• a screw clamping the stator between the inboard bracket and the outboard bracket;
• an armature comprising a shaft being elongate in an axial direction, a commutator supported by the shaft, and a set of windings being electrically coupled to the commutator;
• a set of bearings mounted to at least one of the inboard bracket and the outboard bracket, the set of bearings providing the shaft with support in a radial direction that is perpendicular to the axial direction, the set of bearings further supporting the shaft in the axial direction so as to position the set of windings proximate the stator;
• a fan housing connected to the inboard bracket, the fan housing defining an inlet that is in fluid communication with the outlet of the inboard bracket;
• a paint sprayer connected in fluid communication with the outlet of the inboard bracket;
• a plurality of fan wheels and a plurality of spacers being in an axially stacked arrangement within the fan housing;
• a nut screwed onto the shaft and thereby exerting a nut-clamping force that holds the plurality of fan wheels and the plurality of spacers to the shaft;
• and
• the plurality of spacers includes a first spacer, the plurality of fan wheels includes a fan wheel, the first spacer has a first axial face comprising a first recessed surface, a first peripheral rim, and a first step extending in the axial direction between the first recessed surface and the first peripheral rim, both the first recessed surface and the first peripheral rim being urged by the nut-clamping force toward a substantially planar surface of the fan wheel.

A motor-driven fan configured to operate at 15,000 to 30,000 rpm for compressing air to less than 15 psig, comprising:

• an inboard bracket defining an outlet;
• an outboard bracket;
• a stator comprising a plurality of laminations;
• a screw clamping the stator between the inboard bracket and the outboard bracket;
• an armature comprising a shaft being elongate in an axial direction, a commutator supported by the shaft, and a set of windings being electrically coupled to the commutator;
• a set of bearings mounted to at least one of the inboard bracket and the outboard bracket, the set of bearings providing the shaft with support in a radial direction that is perpendicular to the axial direction, the set of bearings further supporting the shaft in the axial direction so as to position the set of windings proximate the stator;
• a fan housing connected to the inboard bracket, the fan housing defining an inlet that is in fluid communication with the outlet of the inboard bracket;
• a paint sprayer connected in fluid communication with the outlet of the inboard bracket;
• a plurality of fan wheels and a plurality of spacers being in an axially stacked arrangement within the fan housing;
• a nut fastening the plurality of fan wheels and the plurality of spacers to the shaft;
• and
• the plurality of fan wheels includes a fan wheel comprising a sheet metal disk and a sheet metal fan blade, the sheet metal disk defining a tab opening, the sheet metal fan blade comprising a leading edge, a trailing edge, and a sheet metal tab, the shaft being closer to the leading edge than to the trailing edge, the sheet metal tab being closer to the trailing edge than to the leading edge, the sheet metal tab extending into the tab opening of the sheet metal disk, the fan blade having a blade height extending in the axial direction, the sheet metal tab being a tail distance from the trailing edge, the tail distance being greater than zero, the blade height being at least three times greater than the tail distance.

A motor-driven fan configured to operate at 15,000 to 30,000 rpm for compressing air to less than 15 psig, comprising:

• an inboard bracket defining an outlet;
• an outboard bracket;
• a stator comprising a plurality of laminations;
• a screw clamping the stator between the inboard bracket and the outboard bracket;
• an armature comprising a shaft being elongate in an axial direction, a commutator supported by the shaft, and a set of windings being electrically coupled to the commutator;
• a set of bearings mounted to at least one of the inboard bracket and the outboard bracket, the set of bearings providing the shaft with support in a radial direction that is perpendicular to the axial direction, the set of bearings further supporting the shaft in the axial direction so as to position the set of windings proximate the stator;
• a fan housing connected to the inboard bracket, the fan housing defining an inlet that is in fluid communication with the outlet of the inboard bracket;
• a paint sprayer connected in fluid communication with the outlet of the inboard bracket;
• a plurality of fan wheels and a plurality of spacers being in an axially stacked arrangement within the fan housing;
• a nut fastening the plurality of fan wheels and the plurality of spacers to the shaft;
• and
• the plurality of fan wheels includes a fan wheel comprising a sheet metal disk and a sheet metal fan blade, the sheet metal disk defining a tab opening, the sheet metal fan blade comprising a leading edge, a trailing edge, and a sheet metal tab, the shaft being closer to the leading edge than to the trailing edge, the sheet metal tab being closer to the trailing edge than to the leading edge, the sheet metal tab extending into the tab opening of the sheet metal disk, the fan blade having a blade height extending in the axial direction, the fan blade having a blade material thickness perpendicular to the blade height, the sheet metal tab being a tail distance from the trailing edge, the tail distance being greater than zero but less than three times the blade material thickness.