Patent · US Expired

Strobe alarm circuit

US5128591A · kind A · utility

23Cited by
13References
13Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJul 10, 1991
Grant dateJul 7, 1992
Priority date
Expiry dateJul 10, 2011

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH05B41/34
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A strobe light circuit for flashing a flashtube at a desired frequency includes a transformer the primary of which is repetitively connected and disconnected across a D.C. power source by a switch so that energy stored in the primary winding during closed periods of the switch is transferred to the secondary winding of the transformer, with a step-up in voltage, during open periods of the switch, and through a diode to an energy-storing capacitor connected in parallel with the flashtube. The closed period of each switch cycle is initiated at regular intervals by a timing signal and the open period is initiated in response to the attainment of a predetermined voltage across a capacitor connected across the power source indicating that sufficient energy is being stored in the primary winding during each cycle such that the energy transferred to the energy-storing capacitor during the open period of all cycles occurring during one flash period will be sufficient to enable the flashtube to produce a flash when triggered. A flash unit associated with the flashtube includes a trigger circuit that responds to two closely following trigger pulses to produce a double flash during each flash…

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