Steel fastener having grooved shank
CA 2202015 C · Owner: Shelton, Lawrence S. · Inventors: Eckmann, Elizabeth J.; Kish, Frederick A.; Shelton, Lawrence S.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A steel fastener has an elongate shank an enlarged head formed at one end, of the shank and a generally pointed tip formed at the other end of the shank. A grooved portion of the shank is formed with helical grooves defining helical ribs and with annular grooves defining annular rings. The shank has a cylindrical portion between the grooved portion and the tip and a cylindrical portion between the grooved portion and the head. Each of the annular grooves has a root where deepest and each of the annular rings has a crest where largest. The roots define an imaginary cone diverging toward the tip. The crests define an imaginary cone converging toward the tip. The shank has an exterior surface …
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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 April 7, 1997 and granted March 12, 2002. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 7, 2017.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 7, 2019.
- 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.