04004202 is referenced by 49 patents and cites 6 patents.

A motor comprising a permanent magnet rotor, a plurality of stationary stator windings around the rotor, and an electromagnetic commutator for sequentially energizing and deenergizing the windings. The commutator includes a stationary transformer including a primary winding and a plurality of secondary windings equal in number to the number of stationary stator windings. The primary and secondary windings may be in the form of conductive patterns on printed circuit boards. An oscillator supplies a high frequency A.C. signal to the transformer primary. An apertured shield located between the primary and secondary windings rotates with the rotor and causes the secondary windings to be energized in sequence. Switch means, which may be transistors associated with the stationary stator windings are closed and opened in sequence, in response to energization and deenergization of the transformer secondary windings, in order to energize and deenergize the stationary windings in sequence. The position of the transformer secondary windings may be adjusted, or an auxiliary set of secondary windings may be used, to reverse the direction of rotation of the rotor.

Title
Brushless D.C. motor
Application Number
5/545051
Publication Number
4004202
Application Date
January 29, 1975
Publication Date
January 18, 1977
Inventor
Sidney A Davis
East Norwich
NY, US
Agent
Alan H Levine
Assignee
IMC Magnetics Corporation
NY, US
IPC
H02K 29/00
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