Apparatus for controlling motor speed
US4420715A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 2, 1981 |
| Grant date | Dec 13, 1983 |
| Priority date | — |
| Expiry date | Jul 2, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S388/912
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The rotational velocity of a magnetic disc having a magnetic index and driven by a DC motor is controlled. Transducer means responsive to the index derives an electric signal once during each turn of the disc. A clock source derives a plurality of fixed frequency clock waves during each turn of the disc. A counter responsive to the clock source and the electric signal derives a digital signal each time the disc completes a revolution. The digital signal indicates a deviation between the number of clock waves derived by the source during the revolution and a predetermined number, preset into the counter during each turn. A velocity control signal supplied to the motor is controlled by the digital signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.