Remotely monitored sensor and sensing method
CA 2133138 A1 · Owner: Mcmillen, Frederick H. · Inventors: Mcmillen, Frederick H.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An environmental condition sensor and method for remotely monitoring an environmental condition in a building or dwelling. An environmental condition sensor such as a temperature sensor is, connected across a phone line at the remote site. If the environmental conditions being monitored are acceptable the sensor, maintains an open circuit. If the environmental conditions become unacceptable, the sensor connects the phone tip and ring lines together. A call to the remote site will cause the telephone to ring if conditions are normal, or return a busy signal if something is wrong. Therefore, a remote site can be monitored using a telephone line and not incur toll charges since the call never …
Read the whole patent
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
- Filed September 28, 1994. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 28, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 28, 2016.
- 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.