Method for making container closures
CA 1053081 A · Owner: Lovell, Walter C. · Inventors: Lovell, Walter C.; Grise, Frederick G.J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Our United States Patent 3.881,437 and corresponding Canadian Patent 1,016,416 discloses successive steps for providing in sheet metal a fractured but integral section whereby a disruptable container closure is at least partly defomed. In contradistinction thereto the present method of creating a tear line in metal, of particular advantage when such a weakening line is to be uniformly reproduced in tougher-sheet metal involves combining the initial, steps of (a) bending the largely unrestrained sheet material to form the closure periphery with tension inherent therein and (b) concurrently coining, longitudinally that portion of the periphery which is in tension thus to induce exactly to the …
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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
- Granted April 24, 1979. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended April 24, 1996.
- 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.