Four wire multi-satellite intrusion alarm with multiplex annunciation
CA 1106464 A · Owner: Contronic Controls Limited · Inventors: Humphries, Peter E.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An intrusion alarm system has a number of satellites each connected to a master by an unshielded cable having only four conductors, namely two power conductors, a drive signal conductor which supplies drive to the satellite transmitter and the satellite control circuit, and an alarm conductor. When an intrusion is detected by a satellite, its control circuit transmits a high level alarm signal on the alarm conductor to the master and also sets a latch in the satellite. The master has a rocker switch which an investigator turns off when he arrvies at the supervised premises. This turns off the drive signal to the satellite and causes a counter in the master to send a set of interrupting …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Granted August 4, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended August 4, 1998.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.