Method of hydroforming tubular members
CA 2339840 A1 · Owner: R.J. Tower Corporation · Inventors: Birtch, Wallace R.; Lotspaih, Steven R.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Tubular members (10) for use in vehicle frames are easily and economically produced using a hydroforming process in which a high pressure fluid is presented to the interior of a tubular member (10) thus causing the tube to , expand to meet the interior walls of a forming die (35). Tubular members (10) can be formed having significant variations in their circumference diameter , along their lengths, or gage along their lengths by using a stamped blank (15) having a predetermined shape which is formed into a preformed tube (25) which roughly mirrors the shape of the desired finished tubular member (10).
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 August 19, 1999. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended August 19, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by August 19, 2021.
- 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.