Motor pulse extraction system
US4684858A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 3, 1985 |
| Grant date | Aug 4, 1987 |
| Priority date | — |
| Expiry date | Sep 3, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S388/912
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
An improved system is provided for accurately referencing the revolving motion of electric motors used as positioning devices, and is particularly applicable to the automatic positioning and repositioning of ground station antennas in the reception of satellite TV signals. The system utilizes the action of the positioning motor itself as a reference and involves the extraction and counting of variations in the form of pulses produced in the current within the motor as a result of pulses generated, during motor operation, by the commutation process. A low impedance source senses the motor current pulses and feeds them to an active lowpass filter which suppresses any high frequency noise produced during motor commutation. Peak following circuitry, including separate positive and negative peak detectors, detects and follows the positive and negative peaks of the motor current pulses and produces a pulsating output waveform which is proportional to the number of motor current pulses detected by the peak detectors. The output pulses can be counted to provide an accurate referencing of the motor revolving motion with improved resolution and reduced susceptibility to measurement errors.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.