Method for controlling motor speed
US6111384A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 26, 1998 |
| Grant date | Aug 29, 2000 |
| Priority date | — |
| Expiry date | May 26, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S388/911
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method of controlling motor speed. The motor speed control apparatus includes an encoder in mechanical association with the motor. The encoder has one channel providing an encoder signal having a rising and falling state transition for each period of the encoder signal. The periodic frequency of the state transitions are used to precisely measure instantaneous motor speed. A comparitor then compares the periodic frequency with a predetermined motor speed to provide an error signal, representative of the difference. A feedback control system affects the motor speed dependent on the error signals. In a further embodiment, the encoder includes two channels and four state transitions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.