Switchboard control system
CA 1193701 A · Owner: Fujitsu Limited · Inventors: Nagahama, Yasushi; Matsuura, Yoshiaki; Aoki, Kenzo
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A switchboard control system in which a plurality of switchbaords are connected to a time division exchange and controlled by the time division exchange. A speech signal and a control signal (a signal of key information display, information, subscriber number information and other information necessary for the exchange operation by a switchboard operator), which are delivered and received by each switchboard and the time division exchange, are transmitted together by a common transmission line on a time-division multiplexed basis. On the side of the switchbaords are disposed a position controller, by which the signals are multiplexed and separated and the common transmission line and the …
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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 September 17, 1985. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended September 17, 2002.
- 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.