Improvements in and relating to machines for forming helically wound lock-seam tubing having multiple wall thickness
CA 2125295 A1 · Owner: Bubb, Antony John Allen · Inventors: Bubb, Antony John Allen
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In a machine for the formation of helical lock-seam tubing guide, rollers (24A, 25B) are arranged to locate superposed metal strips (9, 11) in laterally staggered relative positions in such a manner that the strips can be passed through forming and clinching means whilst in the overlapped state, whereby finished tubing has a locked seam with each of the walls joined in the seam being formed by multiple layers of metal strip.
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 October 4, 1993. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended October 4, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by October 4, 2015.
- 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.