Expandible bit
CA 2401917 A1 · Owner: Tesco Corporation · Inventors: Walter, Bruno; Angman, Per G.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A bit has been invented that is expandable from a collapsed position useful , for, tripping, to an radially expanded position for use. The bit is useful to form a borehole, through an earthen formation. In one embodiment the bit can be used alone, without a separate under reamer to expand a well bore below a casing string either, during casing drilling or when extending a well bore below an installed casing string. The bit cutter face includes a center cutter face on a mandrel and an outer cutter, face mounted on an expandable section of a housing disposed about the mandrel. The outer cutter face can be expanded by axial movement of the mandrel within the, housing.
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 September 6, 2002. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 6, 2022.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 6, 2024.
- 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.