Electric motor

• US 8,227,948 B1
• Filed: 01/08/2010
• Issued: 07/24/2012
• Est. Priority Date: 01/09/2009
• Status: Active Grant

• Current Assignee: Hydro-Gear Limited Partnership
• Original Assignee: Hydro-Gear Limited Partnership
• Inventors: Fox, Ivan E., Wyatt, Christopher K., Hendershot, Jim
• Primary Examiner(s): Mullins, Burton
• Application Number:
  US12/684,617
• Time in Patent Office: 928 Days
• Field of Search: 310/50, 310/67.R, 310/88, 310/89, 302/64
• US Class Current: 310/89
• CPC Class Codes: A01D 2101/00 Lawn-mowers
• CPC Class Codes: A01D 34/03 mounted on a vehicle, e.g. a tractor, or drawn by an animal or a vehicle
• CPC Class Codes: A01D 69/02 electric
• CPC Class Codes: B60L 1/003 to auxiliary motors, e.g. for pumps, compressors
• CPC Class Codes: B60L 2200/40 Working vehicles
• CPC Class Codes: B60L 2220/14 Synchronous machines
• CPC Class Codes: B60L 2220/50 Structural details of electrical machines
• CPC Class Codes: B60L 2240/36 Temperature of vehicle components or parts
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2250/26 by pedal actuation
• CPC Class Codes: B60L 2270/145 Structure borne vibrations
• CPC Class Codes: B60L 3/0061 relating to electrical machines
• CPC Class Codes: H02K 1/06 characterised by the shape, form or construction
• CPC Class Codes: H02K 1/28 Means for mounting or fastening rotating magnetic parts on to, or to, the rotor structures
• CPC Class Codes: H02K 11/25 Devices for sensing temperature, or actuated thereby
• CPC Class Codes: H02K 2201/03 Machines characterised by aspects of the air-gap between rotor and stator
• CPC Class Codes: H02K 2201/06 Magnetic cores, or permanent magnets characterised by their skew
• CPC Class Codes: H02K 5/04 Casings or enclosures characterised by the shape, form or construction thereof
• CPC Class Codes: H02K 5/06 Cast metal casings
• CPC Class Codes: H02K 5/1732 : radially supporting the rotary shaft at both ends of the rotor H02K5/1737 takes precedence
• CPC Class Codes: H02K 5/225 : Terminal boxes or connection arrangements specially adapted for submersible motors H02K5/132
• CPC Class Codes: H02K 7/003 : Couplings; Details of shafts means for mounting rotors on shafts H02K1/28
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• CPC Class Codes: Y10T 279/16 : Longitudinal screw clamp
• CPC Class Codes: Y10T 279/33 : Member applies axial force component

Abstract

An electric motor includes an upper housing, a lower housing including a flange for mounting the upper housing thereon and a cone-shaped portion extending away from the flange and the upper housing. The electric motor further includes a stator assembly formed of a first core having a first height and fitted into the upper housing, a rotor assembly rigidly joined to a shaft to rotate therewith in the stator assembly and formed of a second core having a second height, and a hub connected to a lower end of the shaft to rotate therewith in relation to the cone-shaped portion. The hub is configured to secure an operable implement to the electric motor. The second height is greater than the first height.

Claims

1. An electric motor comprising:

an upper housing;

a lower housing including a flange for mounting the upper housing thereon and a cone-shaped portion extending away from the flange and the upper housing;

a stator assembly formed of a first core having a first height and fitted into the upper housing;

a rotor assembly rigidly joined to a shaft to rotate therewith in the stator assembly, the rotor assembly formed of a second core having a second height; and

a hub connected to a lower end of the shaft to rotate therewith in relation to the cone-shaped portion, the hub being configured to secure an operable implement to the electric motor,

wherein,

the second height is greater than the first height.

2. The electric motor of claim 1, further comprising an upper bearing fitted onto an upper end of the shaft and slip-fitted into an upper cylindrical pocket formed within the upper housing, and a lower bearing fitted onto the lower end of the shaft and slip-fitted into a lower cylindrical pocket formed within the cone-shaped portion.

3. The electric motor of claim 1, wherein the first core is formed by stacking a plurality of first laminations, and the second core is formed by stacking a plurality of second laminations.

4. The electric motor of claim 3, wherein the plurality of first laminations are skewed relatively to an axis of rotation of the rotor assembly.

5. The electric motor of claim 4, wherein the plurality of second laminations are skewed relatively to the axis of rotation of the rotor assembly.

6. The electric motor of claim 3, wherein the rotor assembly comprises magnets which extend above and below the stacked plurality of first laminations of the stator assembly.

7. The electric motor of claim 2, wherein the upper and lower housings form a sealed motor housing when securely attached to one another.

8. The electric motor of claim 7, wherein the upper and lower bearings position the shaft within the sealed motor housing.

9. The electric motor of claim 2, wherein the shaft comprises upper and lower shoulders to position the upper and lower bearings, respectively.

10. The electric motor of claim 9, wherein the shaft further comprises a middle shoulder to position the rotor assembly along the shaft.

11. The electric motor of claim 2, wherein the upper bearing is separated from contact with an inside upper surface of the upper cylindrical pocket by a spacer.

12. The electric motor of claim 1, wherein the lower housing further comprises a rim that provides an overlapping joint with the upper housing.