04603283 is referenced by 34 patents and cites 12 patents.

A variable speed control for an encoderless, brushless, direct current motor. An input signal, representing a desired speed of the motor, is received by both a variable power supply and a counter. The counter responsively issues a sequence of signals corresponding to particular motor windings to be energized. The variable power supply issues a motor supply voltage in accordance with the input signal as well. An error corrector circuit is connected to both the counter and the windings of the motor. The corrector circuit senses a voltage waveform on a winding when the counter signal indicates that the winding is not energized. If the winding voltage waveform deviates from a predetermined standard, the corrector circuit gives a correction command to the variable power supply. The variable power supply accordingly increases or decreases the motor supply voltage.

Title
Variable speed control for a brushless direct current motor
Application Number
6/740864
Publication Number
4603283
Application Date
June 3, 1985
Publication Date
July 29, 1986
Inventor
Norman E Oltendorf
Algonquin
IL, US
Agent
Allegretti Newitt Witcoff & McAndrews
Assignee
Bodine Electric Company
IL, US
IPC
H02P 6/02
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