Gateway unit
CA 2518871 C · Owner: Tsuji, Kiyotaka · Inventors: Tsuji, Kiyotaka
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A gateway unit for mutually connecting subscriber network public switched telephone network (PSTN) and packet communication network comprising subscriber network interface connected to subscriber network PSTN interface connected to line exchange network exchange unit exchange-connecting communication path among subscriber network PSTN and packet communication network, control unit controlling connecting state of communication path at exchange unit signal conversion unit converting form of signal transmitted and received between exchange unit and packet communication network into forms suitable for communication protocol of packet communication network and communication protocol of …
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 12, 2005 and granted June 4, 2013. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 12, 2025.
- Certificates of supplementary protection extend only drug patents, and it isn't classified as one.
- 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.