Isdn line circuit monitor system
CA 2050571 C · Owner: Kawakami, Takaaki · Inventors: Orita, Akira; Sakata, Tetsuya; Kawakami, Takaaki
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In an ISDN line circuit channel monitor system having a digital line circuit controller a line circuit, network and a call processor accommodating network there are provided monitor equipment and a connection making part. The monitor equipment is coupled to the digital line circuit controller, the first network or the second network, and monitors D and B channels of a basic interface and a primary rate interface. The connection making part connects to the monitor equipment time slots related to a monitored channel of a terminal in conformity with either the basic interface or the primary rate interface.
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 3, 1991 and granted January 28, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 3, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 3, 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.