04617499 is referenced by 12 patents and cites 6 patents.

A brushless motor comprises a magnet having a plurality of pole faces, a plurality of conductors mounted adjacent to the pole faces, and a plurality of phase coils connected together at a neutral point. The magnet is included in the motor rotor and the phase coils are included in the motor stator. A high-frequency signal source supplies a high-frequency signal to the neutral point, whereby changes in eddy current loss and thus the position of the rotor with respect to the stator are detected.

Title
Brushless motor
Application Number
6/800293
Publication Number
4617499
Application Date
November 21, 1985
Publication Date
October 14, 1986
Inventor
Masami Yuasa
Tokyo
JP
Agent
Alvin Sinderbrand
Lewis H Eslinger
Assignee
Sony Corporation
JP
IPC
H02K 29/00
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