Inductive load drive circuit utilizing a bi-level output comparator and a flip-flop to set three different levels of load current
US4327394A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 28, 1979 |
| Grant date | Apr 27, 1982 |
| Priority date | — |
| Expiry date | Jun 28, 1999 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02D2041/2058
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
Comparator means respond to the current levels through an inductive load to generate HIGH and LOW level outputs causing first switch means to connect and disconnect power to the load. When the load current initially exceeds a peak load actuation level, flip-flop means responsive to the corresponding change in comparator output levels change the current through an auxilliary sense resistor coupled to the sense input of the comparator means. In one embodiment, a one-shot multivibrator prevents a change in the current to the auxilliary sense resistor for a fixed period after the commencement of a load actuation signal. The subsequent HIGH and LOW comparator output levels are fed back to the comparator reference input to switch the reference voltage thereat so as to represent first and second levels of the current sufficient to maintain actuation of the load.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.