04255696 is referenced by 37 patents and cites 7 patents.

A stepping motor with toothed stator poles and two sets of oppositely magnetized rotor teeth has its stator poles energized by a driver which responds to input pulses to successively deenergize alternate poles and keep them deenergized and then successively reenergize the alternate poles in the opposite direction. Thereafter the driver successively deenergizes the poles intermediate the alternate poles and keeps them deenergized until all intermediate poles are deenergized and then successively reenergizes the intermediate poles in the other direction until all the intermediate poles are reenergized. This drives the rotor in fractional steps. For larger fractional steps, larger numbers of poles are deenergized in response to each pulse. For even larger fractions the deenergization process is eliminated.

Title
Synchronous motor system
Application Number
654400
Publication Number
4255696
Application Date
November 17, 1976
Publication Date
March 10, 1981
Inventor
John H Field II
Norfolk
MA, US
Agent
Toren McGeady and Stanger
Assignee
Sigma Instruments
MA, US
IPC
G05B 19/40
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