Directionally vented underground distribution surge arrester
CA 2056274 C · Owner: Yaworski, Harry G. · Inventors: Yaworski, Harry G.; Borgstrom, Alan D.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The invention is directed to the provision of an external shield about the periphery of the housing (102) of a surge arrester (100) containing one or more arrester devices (116) to provide an expansion limiting device which permits the housing to expand to a degree necessary to permit the expulsion of arc-generated gases within the housing while limiting the total expansion to a level below the elastic limit of the housing to prevent its destruction and permit its recovery after the gases have been dissipated. The shield may be made of metal, elastomeric materials, reinforced elastomeric materials or plastic, and the shield may be supported about the housing by an external strap (144) 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 November 27, 1991 and granted October 7, 1997. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended November 27, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by November 27, 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.