IP Library Granted Patent US 7,420,308
Granted Patent B2
US 7,420,308 · App. 10/999,218 · Granted Sep 2, 2008

PMBDCM and two phase SRM motor, two phase SRM rotor and stator, and coil wrap for PMBDCM and SRM motors

View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 7,420,308
App. No.
10/999,218
Granted
Sep 2, 2008
Kind
B2
Abstract

A two-phase switched reluctance motor in an embodiment includes a plurality of salient rotor poles that each have asymmetric reluctances about a central radial axis of the respective rotor pole. Each of the rotor poles has the same width, and the rotor poles are operable to provide preferential torque generation in one direction of rotation for all rotor positions. Such preferential torque generation occurs under the influence of an electromagnetic flux, which is provided by a plurality of salient stator poles having substantially the same width as the rotor poles.

Claims (32)

1. A rotor for a two-phase switched reluctance motor, comprising:

a plurality of salient rotor poles that each have asymmetric reluctances about a central radial axis of the respective rotor pole, wherein:

each of the rotor poles has the same rotor pole face arc,

two of the rotor poles are adjacently positioned on the rotor and the asymmetric reluctances of the two rotor poles have substantially the opposite symmetry, about their respective central radial axes, and

the rotor poles are operable to provide preferential torque generation in one direction of rotation for all rotor positions, under the influence of an electromagnetic flux provided by a plurality of salient stator poles having a pitch that is greater than the rotor pole face arc.

2. The rotor of claim 1 , wherein the rotor poles do not have an extended arcuate portion at a distal end of the respective poles.

3. The rotor of claim 1 , wherein:

two of the plurality of rotor poles are disposed radially opposite one another on the rotor; and

the asymmetric reluctances of the two rotor poles have substantially the same symmetry, about their respective central radial axes.

4. The rotor of claim 1 , wherein the rotor is balanced about an axis of rotation.

5. The rotor of claim 1 , wherein:

the plurality of rotor poles are provided in pairs positioned radially opposite one another on the rotor; and

for each pair of rotor poles, the asymmetric reluctances of the paired rotor poles have substantially the same symmetry, about their respective central radial axes.

6. The rotor of claim 5 , wherein for at least two pairs of adjacent rotor poles, the asymmetric reluctances of the adjacently paired rotor poles have substantially the opposite symmetry, about their respective central radial axes.

7. The rotor of claim 6 , wherein for at least another two pairs of adjacent rotor poles, the asymmetric reluctances of the adjacently paired rotor poles have substantially the same symmetry, about their respective central radial axes.

8. The rotor of claim 1 , wherein the rotor poles are slotted to provide the asymmetric reluctance.

9. The rotor of claim 8 , wherein each of the rotor poles is slotted on both sides of its central radial axis.

10. The rotor of claim 8 , wherein one or more of the slots are partially filled with a permanent magnet.

11. The rotor of claim 8 , further comprising a rotor position sensor disposed in one of the slots.

12. The rotor of claim 1 , wherein the rotor poles are peripherally contoured to provide the asymmetric reluctance.

13. The rotor of claim 1 , wherein:

the rotor poles are peripherally contoured at their distal ends to provide the asymmetric reluctance; and

for each rotor pole, a portion of the distal end on each side of the rotor pole's central axis is contoured to have an arc different from that of a circular arc.

14. A rotor for a two-phase switched reluctance motor, comprising:

a plurality of salient rotor poles that are each peripherally contoured to provide asymmetric reluctance about a central radial axis of the respective rotor pole, wherein:

each of the rotor poles has the same rotor pole face arc, and

the rotor poles are operable to provide preferential torque generation in one direction of rotation for all rotor positions, under the influence of an electromagnetic flux provided by a plurality of salient stator poles having a tooth pitch that is greater than the rotor pole face arc.

15. A rotor for a two-phase switched reluctance motor, comprising:

a plurality of salient rotor poles, each rotor pole is peripherally contoured at its distal end to provide asymmetric reluctance about a central radial axis of the rotor pole, wherein:

each of the rotor poles has the same rotor pole face arc,

for each rotor pole, a portion of the distal end on each side of the rotor pole's central axis is contoured to have an arc different from that of a circular arc, and

the rotor poles are operable to provide preferential torque generation in one direction of rotation for all rotor positions, under the influence of an electromagnetic flux provided by a plurality of salient stator poles having a tooth pitch that is greater than the rotor pole face arc.

Assignments (7)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jan 8, 2013
From: RBC MANUFACTURING CORPORATION
To: REGAL BELOIT AMERICA, INC.
Reel/Frame 029582/0236 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jan 7, 2013
From: RAMU, INC.
To: RBC MANUFACTURING CORPORATION
Reel/Frame 029577/0145 →
LICENSE Recorded Mar 1, 2011
From: MTI MOTORS, LLC
To: RAMU, KRISHNAN
Reel/Frame 025876/0664 →
LICENSE Recorded Mar 1, 2011
From: RAMU, KRISHNAN
To: RAMU, INC
Reel/Frame 025876/0615 →
LICENSE Recorded Mar 1, 2011
From: PANAPHASE TECHNOLOGIES, LLC
To: MTI MOTORS, LLC
Reel/Frame 025876/0600 →
LICENSE Recorded Mar 23, 2007
From: VIRGINIA TECH INTELLECTUAL PROPERTIES, INC.
To: PANAPHASE TECHNOLOGIES, LLC
Reel/Frame 019116/0463 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Apr 4, 2005
From: RAMU, KRISHNAN; STALEY, AMANDA MARTIN
To: VIRGINIA TECH INTELLECTUAL PROPERTIES, INC.
Reel/Frame 016429/0659 →