Patent · US Expired

Citizens alarm system

US4040013A · kind A · utility

14Cited by
13References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJan 9, 1975
Grant dateAug 2, 1977
Priority date
Expiry dateJan 9, 1995

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG08B25/001
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A combined police and fire alarm system has provision for voice communication between street corner boxes and a central station via existing telegraphic cables. The boxes automatically transmit identification signals to the central station upon being activated. The central station can check out the boxes by causing them to transmit their identification signals and an audio test signal.

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