Stepper motor controllers
US5206571A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 3, 1991 |
| Grant date | Apr 27, 1993 |
| Priority date | — |
| Expiry date | May 3, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P8/36
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A driver for a stepper motor including means (Q45, 45, 47, 402) for sampling the current in a motor winding (43) at an instant determined by means (401, 400)for generating a predetermined delay following winding commutation. The sample is compared with winding current by a comparator (403) the output of which is stored at a subsequent instant in a flip-flop (416) to provide an output (42). Current generated within the windings due to rotor motion provide a difference in output when the motor is running or blocked. The invention provides a solution to the problem of motion detection of a stepper motor without recourse to a positional sensor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.