Electric motor
An electric motor having a frame, a rotor assembly, and a stator assembly. The rotor assembly has a magnet, a bearing assembly, an impeller, and a shaft. The bearing assembly has a first bearing, a second bearing, and a biasing element between the first and second bearings. The first bearing is mounted to the frame by an o-ring, and the second bearing is mounted to the frame by adhesive.
1. An electric motor comprising:
a frame;
a rotor assembly comprising a magnet, a bearing assembly, an impeller, and a shaft, wherein the bearing assembly comprises:
a first bearing soft-mounted to the frame by an O-ring;
a second bearing mounted to the frame by adhesive; and
a biasing element between the first and second bearings, wherein the first bearing is located closer to the impeller than the second bearing; and
a stator assembly comprising a plurality of c-shaped stator cores, wherein the stator assembly is soft-mounted to the frame by a deformable stator mounting member.
2. The electric motor of claim 1 , wherein the frame comprises an annular groove within which the O-ring sits.
3. The electric motor of claim 1 , wherein the frame comprises an uninterrupted surface covering the bearing assembly.
4. The electric motor of claim 1 , wherein the bearing assembly is located downstream of the impeller.
5. The electric motor of claim 1 , wherein the frame comprises an inner wall and an outer wall, the inner wall having a bore for receiving the bearing assembly, and the magnet is located downstream of the bearing assembly, outside the bore of the inner wall.
6. The electric motor of claim 1 , wherein the impeller is in direct contact with at least a portion of the first bearing.
7. The electric motor of claim 1 , wherein the O-ring is offset from a centre-point of the first bearing.
8. The electric motor of claim 7 , wherein the O-ring is axially offset in a direction parallel to an axis of rotation of the impeller.
9. The electric motor of claim 1 , wherein the frame includes a protrusion that cooperates with a recess of the impeller to form a seal.
10. The electric motor of claim 1 , wherein the stator assembly further comprises a bobbin assembly having a centre portion and a plurality of arm portions that extend from the centre portion.
11. The electric motor of claim 10 , wherein the centre portion of the bobbin assembly includes a bore configured to receive the magnet of the rotor assembly.
12. The electric motor of claim 10 , wherein the stator assembly further comprises a winding wound around an arm portion of the bobbin assembly that is configured to induce a magnetic field in a c-shaped stator core of the plurality of c-shaped stator cores.
13. The electric motor of claim 12 , wherein:
each arm portion of the plurality of arm portions of the bobbin assembly includes an aperture; and
each c-shaped stator core of the plurality of c-shaped stator cores slots into a corresponding aperture of the bobbin assembly.
14. The electric motor of claim 1 , wherein the frame comprises a lug that extends from an inner wall of the frame in an axial direction, the lug being a mounting point for the stator assembly.
15. The electric motor of claim 14 , wherein the stator assembly comprises a recess configured to interface with the lug of the frame.