System for detecting an alarm
US4536751A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 23, 1983 |
| Grant date | Aug 20, 1985 |
| Priority date | — |
| Expiry date | Jun 23, 2003 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG08B13/08
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A system for detecting an alarm for emergency situations of a door or a window of a building or house in a predetermined guard area, comprising: an alarm circuit, including a plurality of alarm switch units for detecting emergencies and a resistor and a capacitor connected between first contacts and second contacts of the alarm switch units; and an alarm device, including a detecting circuit for detecting voltage changes of a predetermined measuring point, a pulse oscillator for generating a pulsating voltage, and a transistor for repeatedly turning on and off the current in response to the pulsating voltage applied from the pulse oscillator.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.