Three stage switching unit
CA 2190104 C · Owner: Telefonaktiebolaget Lm Ericsson · Inventors: Buhrgard, Magnus Karl Sven
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention comprises a three-step switching unit comprising a number of incoming group related conductors every group connected to a first switching stage formed as, an input circuit, a number of outgoing group related conductors, every group connected to a second switching stage, formed as an output circuit and a third switching stage. A control unit coacts with said switching stages in order to connect one of said incoming conductors with a selected outgoing conductor by means of a connecting path pointed out through said between related third switching stage. Each of the outgoing conductors belonging to said, first switching stage coacts with an electro-optical converter. Respective …
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 2, 1995 and granted June 1, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 2, 2015.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 2, 2017.
- 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.