Patent · US Expired

Protective circuit utilizing multilevel power supply output

US3987342A · kind A · utility

6Cited by
9References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 24, 1975
Grant dateOct 19, 1976
Priority date
Expiry dateNov 24, 1995

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02H3/06
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A power supply has both high and low voltage power sources connected to a common output terminal. A switching circuit is connected between the high voltage source and this terminal, the switching circuit being controlled by a control circuit. The control circuit operates in response to malfunction and temperature sensors when these sensors have outputs indicative of equipment operating conditions outside of predetermined ranges for each of the sensed parameters. When the control circuit is not being actuated by an output from one of the sensors, the switching circuit is actuated to connect the high voltage output to the output terminal. In the event, however, that one of the temperature or malfunction sensors senses a condition outside of range, the control circuit is actuated, thereby deactuating the switching circuit to remove the high voltage output from the output terminal, leaving low voltage output. The control circuit operates in conjunction with a timer-reset circuit which resets the control circuit cyclically after a predetermined timing cycle. With each resetting, the control circuit will be reactuated by one of the sensors only if an out-of-range condition still exists. …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.