Apparatus and method of using the stator coils of an electric motor to magnetize permanent magnets of the motor rotor when the span of each stator coil is smaller than the width of each permanent magnet pole
AssigneeEmerson Electric Co.
InventorsMark E. Carrier, Alan O. Crapo
Life of this patent
Estimating the term…
Abstract
An apparatus and its method of use enable magnetizing the permanent magnets of an electric motor rotor using the winding coils of the motor stator when the circumferential width of each rotor permanent magnet pole is larger than the circumferential width of each stator winding coil.
Claims40
An apparatus for magnetizing permanent magnet poles of a rotor of an electric motor with the rotor mounted inside a plurality of stator windings of a stator of the motor, the apparatus comprising:
- a magnetizer with means for connecting the magnetizer to the plurality of stator windings to supply a magnetizing current to the stator windings;
- and
- a motive device operatively connected to the rotor for selectively rotating the rotor relative to the stator.
A method of magnetizing permanent magnets on a rotor of an electric motor that is assembled for rotation in a plurality of stator windings of a stator of the electric motor, the method comprising:
- rotating the rotor in the stator to a first position of the rotor relative to the stator;
- applying a first magnetizing electric current to the windings of the stator with the rotor in the first position relative to the stator;
- rotating the rotor in the stator to a second position of the rotor relative to the stator;
- and
- applying a second magnetizing electric current to the windings of the stator with the rotor in the second position relative to the stator.
A method of magnetizing permanent magnets on a rotor of an electric motor that is assembled for rotation in a plurality of stator windings of a stator of the electric motor, the method comprising:
- applying a first magnetizing electric current to the stator windings with the rotor in a first position relative to the stator;
- rotating the rotor in the stator to a second position of the rotor relative to the stator;
- applying a second magnetizing electric current to the stator windings with the rotor in the second position relative to the stator;
- and,
- rotating the rotor in the stator and sensing a magnetic flux produced to determine whether the rotor was sufficiently magnetized.
Dependencies are inferred from the claim text.