US 6,982,532 B2
Electric machine
Paul Steven Mullin, Xenia, Ohio (US); Albert Keith Pant, Carlisle, Ohio (US); Dan Mircea Ionel, Fox Point, Wis. (US); Brian Thomas Branecky, Oconomowoc, Wis. (US); William Louis Mehlhorn, Menomonee Falls, Wis. (US); Alan Edward Lesak, Franklin, Wis. (US); and Anthony Joseph Coloma, Troy, Ohio (US)
Assigned to A. O. Smith Corporation, Milwaukee, Wis. (US)
Filed on Dec. 08, 2003, as Appl. No. 10/730,153.
Prior Publication US 2005/0122073 A1, Jun. 09, 2005
Int. Cl. H02P 6/00 (2006.01)
U.S. Cl. 318—254 74 Claims
OG exemplary drawing
 
1. An electric machine comprising:
a stator assembly having a stator core and a coil supported by the stator core;
a rotor assembly having a shaft and a rotor supported by the shaft for rotation with the shaft relative to the stator core, the rotor having a first magnetic pole and a second magnetic pole, the rotor being in magnetic interaction with the stator core;
a single sensor configured to detect magnetic polarities of the rotor as the rotor rotates relative to the sensor and to generate a signal representing the detected magnetic polarities of the rotor, the signal being in a first state when the first magnetic pole is detected and a second state when the second magnetic pole is detected, the signal being inverted to form an inverted signal, the signal being utilized to control current through the coil in a first direction when the signal is in the first state and the inverted signal being utilized to control current through the coil in a second direction when the signal is in the second state, the current through the coil resulting in an alternating magnetic field in the stator core; and
wherein at least a portion of the rotor and at least a portion of the shaft are encapsulated in an encapsulation material, and wherein the encapsulation material connects the rotor to the shaft.