Resources Contact Us Home
Variable speed A.C. motor

Image Number 2 for United States Patent #4227136.

This invention is directed to a controllable infinitely variable speed A.C. electrical motor, comprising a rotor having a core of soft magnetic material carrying a peripheral layer of magnetizable permanent magnet material, which layer is magnetized by a stationary excitation coil energized with A.C. potential so that the peripheral layer assumes a selected configuration of north and south magnetic poles as the rotor revolves; A.C. potential is also applied to windings in slots in the stator core to provide a plurality of magnetic poles in the stator coacting magnetically with the configuration of north and south magnetic poles in the layer of magnetic material in the rotor, whereby to cause the rotor to revolve. Phase shifting means are provided in the circuit leading to the excitation coil to enable the phase of the A.C. current being supplied thereto to be shifted with respect to the phases of the A.C. current being supplied to the windings in the stator, and such phase shifting causes the rotor to speed up or slow down over a substantial range of speeds.

  Recently Added Patents
Liquid crystal display device
Matching a usage history to a new cloud
High surface area composition for use in the catalytic hydroconversion of a heavy hydrocarbon feedstock, a method making such composition and its use
Automatic engine oil life determination with a factor for oil quality
Sublingual coated tablet of fentanyl
Methods of packaging imager devices and optics modules, and resulting assemblies
Water purification using energy from a steam-hydrocarbon reforming process
  Randomly Featured Patents
Fast connecting/disconnecting element for component mounted on a PCB
Compounds and methods for the diagnosis and treatment of ehrlichia infection
Electrical connector for use between media connectors and computer communications cards
Mitotic kinesin inhibitors and methods of use thereof
System and method for calibrating multi-axial measurement devices using multi-dimensional surfaces in the presence of a uniform field
Thin film write head with improved yoke to pole stitch
Flexible polyurethane foam and method for its production
Semiconductor chip package
Golf ball holder
Confidential electronic election system