Front door telephone system
CA 2041880 A1 · Owner: Fonel Oy · Inventors: Kangas, Matti; Kangas, Matti
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
57) Abstract, The front door telephone system is intended to be used especially in apartment buildings. It comprises mainly a keyboard (2) located by the entrance of the building a, central unit (5) and a combination of remote units (8) connected to the central unit (5) and located in the apartments of the buildings. The front door telephone system specifically facilitates opening of the front door (1) from the remote unit (8). Fig. 1
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 May 6, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended May 6, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by May 6, 2013.
- 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.