Title:
BRUSHLESS DC MOTOR WITH PERMANENT MAGNET ROTOR
Document Type and Number:
WIPO Patent Application WO/2014/062887
Kind Code:
A3
Abstract:
A brushless DC motor comprises a permanent magnet rotor rotating coaxially with and inside of the stator, separated by a radial, axially extending gap. The rotor can be formed of four or more permanent, e.g., ferrite ceramic magnets, spaced substantially equidistantly circumferentially around the rotor and extending radially along the axial length of the rotor. The preferred ferrite magnets are substantially corrosion resistant, and thus durable in the wet rotor environment, in which it may be used, sufficient to withstand the effects of even hot salt water. Preferably, four of the permanent magnets are bar magnets, i.e., rectangular in cross-section, extending radially and perpendicularly to the adjacent magnets. Most preferably, the bar magnets are separated by generally wedge-shaped, or quadrant-shaped, sections of magnetic material. The permanent magnets are polarized so that the north-south flux lines extend transversely to each adjacent magnet, most preferably forming a so-called Halbach Array.
Inventors:
WU DI (US)
STAKEV VLADISLAV MILCHEV (US)
BIRKENSTOCK ROBERT F (US)
STAKEV VLADISLAV MILCHEV (US)
BIRKENSTOCK ROBERT F (US)
Application Number:
PCT/US2013/065379
Publication Date:
July 03, 2014
Filing Date:
October 17, 2013
Export Citation:
Assignee:
TACO INC (US)
International Classes:
H02K15/03; H02K21/12
Foreign References:
US20090001831A1 | 2009-01-01 | |||
US20090121571A1 | 2009-05-14 | |||
US20100133942A1 | 2010-06-03 | |||
US20060106681A1 | 2006-05-18 | |||
US4558295A | 1985-12-10 | |||
US5424632A | 1995-06-13 | |||
US4998865A | 1991-03-12 |
Attorney, Agent or Firm:
SUTTON, Paul, J. (Barry GSutton Magidoff LLP,909 Third Avenue,27th Floor, NY, US)
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