Patent · US Expired

Phase locked loop motor speed control

US4307324A · kind A · utility

11Cited by
5References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 25, 1980
Grant dateDec 22, 1981
Priority date
Expiry dateMar 25, 2000

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S388/911
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A precision motor speed control system employing a phase locked loop in which the inertial mass of the motor, its tachometer and motor driven devices, such as fly wheels, tape transports, etc., perform the functions of the usual low pass filter and voltage control oscillator.

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