04311933 is referenced by 61 patents and cites 6 patents.

A brushless D.C. motor has electrical power switched between the phase windings by means of a circuit which includes a plurality of hall effect switches. The hall effect switches are operated by a plurality of arcuate commutating magnets which are radially polarized and are disposed axially adjacent to field magnets which are also radially polarized. Ordinarily, the direction of radial polarization of the commutating magnets and the field magnets will be opposite.

Title
Brushless direct current motor
Application Number
6/70069
Publication Number
4311933
Application Date
August 27, 1979
Publication Date
January 19, 1982
Inventor
Joseph J Schegan
Wallingford
CT, US
William D Riggs
Southington
CT, US
Agent
Robert S Smith
Assignee
North American Philips Corporation
NY, US
IPC
H02K 21/12
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