Recovery of tungsten carbide from scrap mining bits
CA 1090987 A · Owner: Fernand Piche Enterprises Limited · Inventors: Piche, Fernand J.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Tungsten carbide inserts are recovered from scrap mining bits by treatment in a sulphuric acid bath to eat away part of the steel surrounding the inserts and then heating the bit and vibrating the heated bit to knock out the inserts. In a modification used on cross-type bits heat and vibration alone are used.
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
- Granted December 9, 1980. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended December 9, 1997.
- 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.