Field shunting circuit
US4027214A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 28, 1975 |
| Grant date | May 31, 1977 |
| Priority date | — |
| Expiry date | Oct 28, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P7/298
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A circuit for automatically shunting the field winding of a direct current motor and reapplying full field thereto. A low-level pull-in comparator compares a signal proportional to armature current to a low-level reference potential and causes the field to be shunted when the armature current signal falls below the low-level reference potential. A high-level drop-out comparator compares a signal proportional to armature current to a second independent high-level reference potential and causes the full field to be applied when the armature current signal is greater than the high-level reference potential. Prior to actuation, the pull-in comparator disables the drop-out comparator. Upon actuation, the pull-in comparator latches itself in actuated state and enables the drop-out comparator to be actuated. Upon actuation the drop-out comparator unlatches the pull-in comparator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.