Sub-assembly for dust suppression in rock drilling
CA 2133430 C · Owner: D.T.H. Supplies Pty Limited · Inventors: Hanns, David Thomas; Carrall, Christopher Richard
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
This invention concerns an accessory, to be inserted in drill string behind a drill bit, to provide separation of the liquid and air components of a flushing medium. The accessory comprises an inner housing (36) within an outer housing (34). A liquid/gas medium enters through opening (50) onto spiral raceway (48). Holes are provided at intervals along spiral (42). Liquid in the medium is centrifuged by the spiral (42) and projected into the chamber between inner and outer housings (36, 34). The expelled liquid (52) falls to the base (70) of the housing (34) where it passes through apertures (38) into the drill bore. Once the medium has traversed the spiral (42) essentially only gas remains …
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 April 1, 1993 and granted June 15, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended April 1, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by April 1, 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.