The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 12, 1987
Filed:
Apr. 22, 1985
Paul A Desjardins, Commack, NY (US);
Firecom, Inc., Woodside, NY (US);
Abstract
A central protection system suitable for the protection of a building from fire and other hazards includes a set of environmental sensors and circuitry for interrogating the sensors. The system also includes communication and control lines, as well as monitoring circuitry having individual channels coupled to respective ones of the communication and control lines. An inaudible pilot tone of subsonic frequency may be coupled to a communication line, and the corresponding channel of the monitoring circuit includes a detector of the pilot tone. A circuit for the generation of evacuation signals and fire brigade signals is composed of two sections coupled in tandem, and includes sequencing circuitry for the recycling of tones produced by the respective sections.