Branched telephone system
CA 1283231 C · Owner: Nec Corporation · Inventors: Fujisaki, Hisashi; Shimada, Keiko
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A branched telephone system having a plurality of telephones which are connected to a single subscriber line or to single radio apparatus has a function of establishing a priority set condition in which the communicating function of particular one of the telephones is validated to prevent the other telephones from being used, and a function of automatically cancelling such a priority set condition.
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
- Granted April 16, 1991. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended April 16, 2008.
- 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.