Patent · US Expired

Computer controlled motor

US4554499A · kind A · utility

17Cited by
12References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 24, 1984
Grant dateNov 19, 1985
Priority date
Expiry dateOct 24, 2004

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/0329
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

To control a motor, a pulse width modulated signal from a computer is fed to a capacitor which stores each pulse as a voltage proportional to the width of the pulse, the capacitor being reset to zero by a leading edge reset circuit. The voltage on the capacitor is sampled by a sample/hold circuit the output of which is fed to a converter which converts the voltage signal to a frequency signal exponentially related to the voltage, and hence to the pulse width. The converter then powers a driver which drives the motor. The exponential relationship between the pulses and the signal fed to the motor permits a large variationin the frequency signal based on a small variation in pulse width and hence permits accurate control of the motor.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.