Method for pinch free tube forming
CA 2119700 C · Owner: General Motors Corporation · Inventors: Lovell, Michael Harry; Shah, Sanjay Mahasukhlal
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of forming an elongated box shape tubular frame member from a round tube includes the steps of: providing a lower die member having a cavity submerged substantially below the top surface of the lower die and having a cavity width equal to the width of the desired box shape frame member and less than the diameter of the tube. The lower die has an entry opening which opens to the top surface of the die and is defined by angularly disposed funnel walls which converge to intersect with the cavity. The round tubular blank is placed onto the lower die so that the blank rests on the angularly disposed funnel walls above the cavity. The upper die is lowered onto the lower die and has a lid …
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 March 23, 1994 and granted June 16, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 23, 2014.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 23, 2016.
- 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.