Method of and machine for forming compound curvatures in metal sheets by drawing
CA 2056872 A1 · Owner: Johnson, Ray C. · Inventors: Creaser, Charles; Johnson, Ray C.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An improved method of and apparatus for forming sheet material into compound curves by drawing in which critical, positioning, dimensioning and relative curvatures of forming bead stages are provided for such curvatures as sectors of paraboloidal antenna reflectors and other compound curve sheets.
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 December 3, 1991. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended December 3, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 3, 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.