Digital exchange
CA 2241122 A1 · Owner: Kabushiki Kaisha Toshiba · Inventors: Funato, Yasuo; Otsuka, Eiji
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A digital exchange according to the present invention uses a first highway for transmitting PCM data and a second highway. Each of the first and second highways is multiplexed with time division. A transmission rate of the second highway is slower than that of the first highway. A rate conversion circuit converts these transmission rates. The second highway is provided with a port connected to a trunk or a line extending to a telephone. A new channel of the first highway is allocated for the port to use every time when the port receives a calling control information requesting a use of a channel of the first highway.
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 June 19, 1998. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended June 19, 2018.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 19, 2020.
- 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.